diff --git a/3rdparty/carotene/hal/CMakeLists.txt b/3rdparty/carotene/hal/CMakeLists.txt
index 9c66186891..8ca7a7de32 100644
--- a/3rdparty/carotene/hal/CMakeLists.txt
+++ b/3rdparty/carotene/hal/CMakeLists.txt
@@ -60,22 +60,6 @@ function(compile_carotene)
   endif()
 
   add_subdirectory("${CAROTENE_DIR}" "${CMAKE_CURRENT_BINARY_DIR}/carotene")
-
-  if(ARM OR AARCH64)
-    if(CMAKE_BUILD_TYPE)
-      set(CMAKE_TRY_COMPILE_CONFIGURATION ${CMAKE_BUILD_TYPE})
-    endif()
-    check_cxx_compiler_flag("-mfpu=neon" CXX_HAS_MFPU_NEON)
-    check_c_compiler_flag("-mfpu=neon" C_HAS_MFPU_NEON)
-    if(${CXX_HAS_MFPU_NEON} AND ${C_HAS_MFPU_NEON} AND NOT "${CMAKE_CXX_FLAGS} " MATCHES "-mfpu=neon[^ ]*")
-      get_target_property(old_flags "carotene_objs" COMPILE_FLAGS)
-      if(old_flags)
-        set_target_properties("carotene_objs" PROPERTIES COMPILE_FLAGS "${old_flags} -mfpu=neon")
-      else()
-        set_target_properties("carotene_objs" PROPERTIES COMPILE_FLAGS "-mfpu=neon")
-      endif()
-    endif()
-  endif()
 endfunction()
 
 compile_carotene()
diff --git a/CMakeLists.txt b/CMakeLists.txt
index e205886355..69a130169a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -792,9 +792,13 @@ endif()
 
 foreach(hal ${OpenCV_HAL})
   if(hal STREQUAL "carotene")
-    add_subdirectory(3rdparty/carotene/hal)
-    ocv_hal_register(CAROTENE_HAL_LIBRARIES CAROTENE_HAL_HEADERS CAROTENE_HAL_INCLUDE_DIRS)
-    list(APPEND OpenCV_USED_HAL "carotene (ver ${CAROTENE_HAL_VERSION})")
+    if(";${CPU_BASELINE_FINAL};" MATCHES ";NEON;")
+      add_subdirectory(3rdparty/carotene/hal)
+      ocv_hal_register(CAROTENE_HAL_LIBRARIES CAROTENE_HAL_HEADERS CAROTENE_HAL_INCLUDE_DIRS)
+      list(APPEND OpenCV_USED_HAL "carotene (ver ${CAROTENE_HAL_VERSION})")
+    else()
+      message(STATUS "Carotene: NEON is not available, disabling carotene...")
+    endif()
   elseif(hal STREQUAL "openvx")
     add_subdirectory(3rdparty/openvx)
     ocv_hal_register(OPENVX_HAL_LIBRARIES OPENVX_HAL_HEADERS OPENVX_HAL_INCLUDE_DIRS)
diff --git a/modules/calib3d/misc/python/test/test_solvepnp.py b/modules/calib3d/misc/python/test/test_solvepnp.py
index b751e15c74..f7765c0384 100644
--- a/modules/calib3d/misc/python/test/test_solvepnp.py
+++ b/modules/calib3d/misc/python/test/test_solvepnp.py
@@ -39,6 +39,26 @@ class solvepnp_test(NewOpenCVTests):
             obj_points, img_points, cameraMatrix, distCoeffs, reprojectionError=r
         )
 
+    def test_regression_16049(self):
+        obj_points = np.array([[0, 0, 0], [0, 1, 0], [1, 1, 0], [1, 0, 0]], dtype=np.float32)
+        img_points = np.array(
+            [[[700, 400], [700, 600], [900, 600], [900, 400]]], dtype=np.float32
+        )
+
+        cameraMatrix = np.array(
+            [[712.0634, 0, 800], [0, 712.540, 500], [0, 0, 1]], dtype=np.float32
+        )
+        distCoeffs = np.array([[0, 0, 0, 0]], dtype=np.float32)
+        x, r, t, e = cv.solvePnPGeneric(
+            obj_points, img_points, cameraMatrix, distCoeffs
+        )
+        if e is None:
+            # noArray() is supported, see https://github.com/opencv/opencv/issues/16049
+            pass
+        else:
+            eDump = cv.utils.dumpInputArray(e)
+            self.assertEqual(eDump, "InputArray: empty()=false kind=0x00010000 flags=0x01010000 total(-1)=1 dims(-1)=2 size(-1)=1x1 type(-1)=CV_32FC1")
+
 
 if __name__ == '__main__':
     NewOpenCVTests.bootstrap()
diff --git a/modules/calib3d/src/solvepnp.cpp b/modules/calib3d/src/solvepnp.cpp
index 1b76ce82e2..2c7b27fe13 100644
--- a/modules/calib3d/src/solvepnp.cpp
+++ b/modules/calib3d/src/solvepnp.cpp
@@ -1009,7 +1009,10 @@ int solvePnPGeneric( InputArray _opoints, InputArray _ipoints,
 
     if (reprojectionError.needed())
     {
-        int type = reprojectionError.type();
+        int type = (reprojectionError.fixedType() || !reprojectionError.empty())
+                ? reprojectionError.type()
+                : (max(_ipoints.depth(), _opoints.depth()) == CV_64F ? CV_64F : CV_32F);
+
         reprojectionError.create(solutions, 1, type);
         CV_CheckType(reprojectionError.type(), type == CV_32FC1 || type == CV_64FC1,
                      "Type of reprojectionError must be CV_32FC1 or CV_64FC1!");
diff --git a/modules/core/src/matmul.simd.hpp b/modules/core/src/matmul.simd.hpp
index 5c60d3097d..38973ea1a4 100644
--- a/modules/core/src/matmul.simd.hpp
+++ b/modules/core/src/matmul.simd.hpp
@@ -2078,6 +2078,10 @@ MulTransposedR(const Mat& srcmat, const Mat& dstmat, const Mat& deltamat, double
         deltastep = deltastep ? 4 : 0;
     }
 
+#if CV_SIMD_64F
+    v_float64x2 v_scale = v_setall_f64(scale);
+#endif
+
     if( !delta )
         for( i = 0; i < size.width; i++, tdst += dststep )
         {
@@ -2086,22 +2090,41 @@ MulTransposedR(const Mat& srcmat, const Mat& dstmat, const Mat& deltamat, double
 
             for( j = i; j <= size.width - 4; j += 4 )
             {
-                double s0 = 0, s1 = 0, s2 = 0, s3 = 0;
-                const sT *tsrc = src + j;
+#if CV_SIMD_64F
+                if (DataType<sT>::depth == CV_64F && DataType<dT>::depth == CV_64F)
+                {
+                    v_float64x2 s0 = v_setzero_f64(), s1 = v_setzero_f64();
+                    const double *tsrc = (double*)(src + j);
 
-                for( k = 0; k < size.height; k++, tsrc += srcstep )
+                    for( k = 0; k < size.height; k++, tsrc += srcstep )
+                    {
+                        v_float64x2 a = v_setall_f64((double)col_buf[k]);
+                        s0 += a * v_load(tsrc+0);
+                        s1 += a * v_load(tsrc+2);
+                    }
+
+                    v_store((double*)(tdst+j), s0*v_scale);
+                    v_store((double*)(tdst+j+2), s1*v_scale);
+                } else
+#endif
                 {
-                    double a = col_buf[k];
-                    s0 += a * tsrc[0];
-                    s1 += a * tsrc[1];
-                    s2 += a * tsrc[2];
-                    s3 += a * tsrc[3];
-                }
+                    double s0 = 0, s1 = 0, s2 = 0, s3 = 0;
+                    const sT *tsrc = src + j;
 
-                tdst[j] = (dT)(s0*scale);
-                tdst[j+1] = (dT)(s1*scale);
-                tdst[j+2] = (dT)(s2*scale);
-                tdst[j+3] = (dT)(s3*scale);
+                    for( k = 0; k < size.height; k++, tsrc += srcstep )
+                    {
+                        double a = col_buf[k];
+                        s0 += a * tsrc[0];
+                        s1 += a * tsrc[1];
+                        s2 += a * tsrc[2];
+                        s3 += a * tsrc[3];
+                    }
+
+                    tdst[j] = (dT)(s0*scale);
+                    tdst[j+1] = (dT)(s1*scale);
+                    tdst[j+2] = (dT)(s2*scale);
+                    tdst[j+3] = (dT)(s3*scale);
+                }
             }
 
             for( ; j < size.width; j++ )
@@ -2127,23 +2150,45 @@ MulTransposedR(const Mat& srcmat, const Mat& dstmat, const Mat& deltamat, double
 
             for( j = i; j <= size.width - 4; j += 4 )
             {
-                double s0 = 0, s1 = 0, s2 = 0, s3 = 0;
-                const sT *tsrc = src + j;
-                const dT *d = delta_buf ? delta_buf : delta + j;
-
-                for( k = 0; k < size.height; k++, tsrc+=srcstep, d+=deltastep )
+#if CV_SIMD_64F
+                if (DataType<sT>::depth == CV_64F && DataType<dT>::depth == CV_64F)
                 {
-                    double a = col_buf[k];
-                    s0 += a * (tsrc[0] - d[0]);
-                    s1 += a * (tsrc[1] - d[1]);
-                    s2 += a * (tsrc[2] - d[2]);
-                    s3 += a * (tsrc[3] - d[3]);
+                    v_float64x2 s0 = v_setzero_f64(), s1 = v_setzero_f64();
+                    const double *tsrc = (double*)(src + j);
+                    const double *d = (double*)(delta_buf ? delta_buf : delta + j);
+
+                    for( k = 0; k < size.height; k++, tsrc+=srcstep, d+=deltastep )
+                    {
+                        v_float64x2 a = v_setall_f64((double)col_buf[k]);
+                        s0 += a * (v_load(tsrc+0) - v_load(d+0));
+                        s1 += a * (v_load(tsrc+2) - v_load(d+2));
+                    }
+
+                    v_store((double*)(tdst+j), s0*v_scale);
+                    v_store((double*)(tdst+j+2), s1*v_scale);
                 }
+                else
+#endif
 
-                tdst[j] = (dT)(s0*scale);
-                tdst[j+1] = (dT)(s1*scale);
-                tdst[j+2] = (dT)(s2*scale);
-                tdst[j+3] = (dT)(s3*scale);
+                {
+                    double s0 = 0, s1 = 0, s2 = 0, s3 = 0;
+                    const sT *tsrc = src + j;
+                    const dT *d = delta_buf ? delta_buf : delta + j;
+
+                    for( k = 0; k < size.height; k++, tsrc+=srcstep, d+=deltastep )
+                    {
+                        double a = col_buf[k];
+                        s0 += a * (tsrc[0] - d[0]);
+                        s1 += a * (tsrc[1] - d[1]);
+                        s2 += a * (tsrc[2] - d[2]);
+                        s3 += a * (tsrc[3] - d[3]);
+                    }
+
+                    tdst[j] = (dT)(s0*scale);
+                    tdst[j+1] = (dT)(s1*scale);
+                    tdst[j+2] = (dT)(s2*scale);
+                    tdst[j+3] = (dT)(s3*scale);
+                }
             }
 
             for( ; j < size.width; j++ )
@@ -2182,10 +2227,25 @@ MulTransposedL(const Mat& srcmat, const Mat& dstmat, const Mat& deltamat, double
                 double s = 0;
                 const sT *tsrc1 = src + i*srcstep;
                 const sT *tsrc2 = src + j*srcstep;
-
-                for( k = 0; k <= size.width - 4; k += 4 )
-                    s += (double)tsrc1[k]*tsrc2[k] + (double)tsrc1[k+1]*tsrc2[k+1] +
-                         (double)tsrc1[k+2]*tsrc2[k+2] + (double)tsrc1[k+3]*tsrc2[k+3];
+#if CV_SIMD_64F
+                if (DataType<sT>::depth == CV_64F && DataType<dT>::depth == CV_64F)
+                {
+                    const double *v_tsrc1 = (double *)(tsrc1);
+                    const double *v_tsrc2 = (double *)(tsrc2);
+                    v_float64x2 v_s = v_setzero_f64();
+
+                    for( k = 0; k <= size.width - 4; k += 4 )
+                        v_s += (v_load(v_tsrc1+k) * v_load(v_tsrc2+k)) +
+                               (v_load(v_tsrc1+k+2) * v_load(v_tsrc2+k+2));
+                    s += v_reduce_sum(v_s);
+                }
+                else
+#endif
+                {
+                    for( k = 0; k <= size.width - 4; k += 4 )
+                        s += (double)tsrc1[k]*tsrc2[k] + (double)tsrc1[k+1]*tsrc2[k+1] +
+                             (double)tsrc1[k+2]*tsrc2[k+2] + (double)tsrc1[k+3]*tsrc2[k+3];
+                }
                 for( ; k < size.width; k++ )
                     s += (double)tsrc1[k] * tsrc2[k];
                 tdst[j] = (dT)(s*scale);
@@ -2220,11 +2280,30 @@ MulTransposedL(const Mat& srcmat, const Mat& dstmat, const Mat& deltamat, double
                         delta_buf[2] = delta_buf[3] = tdelta2[0];
                     tdelta2 = delta_buf;
                 }
-                for( k = 0; k <= size.width-4; k += 4, tdelta2 += delta_shift )
-                    s += (double)row_buf[k]*(tsrc2[k] - tdelta2[0]) +
-                         (double)row_buf[k+1]*(tsrc2[k+1] - tdelta2[1]) +
-                         (double)row_buf[k+2]*(tsrc2[k+2] - tdelta2[2]) +
-                         (double)row_buf[k+3]*(tsrc2[k+3] - tdelta2[3]);
+#if CV_SIMD_64F
+                if (DataType<sT>::depth == CV_64F && DataType<dT>::depth == CV_64F)
+                {
+                    const double *v_tsrc2 = (double *)(tsrc2);
+                    const double *v_tdelta2 = (double *)(tdelta2);
+                    const double *v_row_buf = (double *)(row_buf);
+                    v_float64x2 v_s = v_setzero_f64();
+
+                    for( k = 0; k <= size.width - 4; k += 4, v_tdelta2 += delta_shift )
+                        v_s += ((v_load(v_tsrc2+k) - v_load(v_tdelta2)) * v_load(v_row_buf+k)) +
+                               ((v_load(v_tsrc2+k+2) - v_load(v_tdelta2+2)) * v_load(v_row_buf+k+2));
+                    s += v_reduce_sum(v_s);
+
+                    tdelta2 = (const dT *)(v_tdelta2);
+                }
+                else
+#endif
+                {
+                    for( k = 0; k <= size.width-4; k += 4, tdelta2 += delta_shift )
+                        s += (double)row_buf[k]*(tsrc2[k] - tdelta2[0]) +
+                             (double)row_buf[k+1]*(tsrc2[k+1] - tdelta2[1]) +
+                             (double)row_buf[k+2]*(tsrc2[k+2] - tdelta2[2]) +
+                             (double)row_buf[k+3]*(tsrc2[k+3] - tdelta2[3]);
+                }
                 for( ; k < size.width; k++, tdelta2++ )
                     s += (double)row_buf[k]*(tsrc2[k] - tdelta2[0]);
                 tdst[j] = (dT)(s*scale);
diff --git a/modules/core/src/parallel_impl.cpp b/modules/core/src/parallel_impl.cpp
index e732830d22..fde8ccfc4d 100644
--- a/modules/core/src/parallel_impl.cpp
+++ b/modules/core/src/parallel_impl.cpp
@@ -40,7 +40,7 @@ DECLARE_CV_PAUSE
 #endif
 #ifndef CV_PAUSE
 # if defined __GNUC__ && (defined __i386__ || defined __x86_64__)
-#   if !defined(__SSE__)
+#   if !defined(__SSE2__)
       static inline void cv_non_sse_mm_pause() { __asm__ __volatile__ ("rep; nop"); }
 #     define _mm_pause cv_non_sse_mm_pause
 #   endif
diff --git a/modules/dnn/include/opencv2/dnn/all_layers.hpp b/modules/dnn/include/opencv2/dnn/all_layers.hpp
index 2e1366aa07..0969ba6c62 100644
--- a/modules/dnn/include/opencv2/dnn/all_layers.hpp
+++ b/modules/dnn/include/opencv2/dnn/all_layers.hpp
@@ -250,7 +250,8 @@ CV__DNN_INLINE_NS_BEGIN
         std::vector<size_t> pads_begin, pads_end;
         CV_DEPRECATED_EXTERNAL Size kernel, stride, pad;
         CV_DEPRECATED_EXTERNAL int pad_l, pad_t, pad_r, pad_b;
-        bool globalPooling;
+        bool globalPooling; //!< Flag is true if at least one of the axes is global pooled.
+        std::vector<bool> isGlobalPooling;
         bool computeMaxIdx;
         String padMode;
         bool ceilMode;
diff --git a/modules/dnn/include/opencv2/dnn/version.hpp b/modules/dnn/include/opencv2/dnn/version.hpp
index 6dd2c39d69..152c8b2522 100644
--- a/modules/dnn/include/opencv2/dnn/version.hpp
+++ b/modules/dnn/include/opencv2/dnn/version.hpp
@@ -6,7 +6,7 @@
 #define OPENCV_DNN_VERSION_HPP
 
 /// Use with major OpenCV version only.
-#define OPENCV_DNN_API_VERSION 20191202
+#define OPENCV_DNN_API_VERSION 20200128
 
 #if !defined CV_DOXYGEN && !defined CV_STATIC_ANALYSIS && !defined CV_DNN_DONT_ADD_INLINE_NS
 #define CV__DNN_INLINE_NS __CV_CAT(dnn4_v, OPENCV_DNN_API_VERSION)
diff --git a/modules/dnn/src/layers/convolution_layer.cpp b/modules/dnn/src/layers/convolution_layer.cpp
index 29361ced04..110d5f7f45 100644
--- a/modules/dnn/src/layers/convolution_layer.cpp
+++ b/modules/dnn/src/layers/convolution_layer.cpp
@@ -1555,19 +1555,6 @@ public:
         const int group = numOutput / outGroupCn;
 
         if (backendId == DNN_BACKEND_INFERENCE_ENGINE_NGRAPH) {
-            if (padMode.empty()) {
-                for (int i = 0; i < adjust_pads.size(); i++) {
-                    if (pads_end[i] < adjust_pads[i])
-                    return false;
-                }
-            } else if (padMode == "SAME") {
-                for (int i = 0; i < adjust_pads.size(); i++) {
-                    if (kernel_size[i] < pads_begin[i] + 1 + adjust_pads[i])
-                        return false;
-                }
-            } else if (padMode == "VALID")
-                return false;
-
             return group == 1;
         }
 
@@ -2334,20 +2321,16 @@ public:
             ieWeights = std::make_shared<ngraph::op::Constant>(ngraph::element::f32, kernel_shape, newWeights.data);
         }
         std::vector<size_t> paddings_end;
-        if (padMode.empty())
-        {
-            for (int i = 0; i < pads_end.size(); i++) {
-                paddings_end.push_back(pads_end[i] - adjust_pads[i]);
-            }
-        }
-        else if (padMode == "SAME")
+        if (padMode == "SAME")
         {
             for (int i = 0; i < pads_begin.size(); i++) {
                 paddings_end.push_back(kernel_size[i] - pads_begin[i] - 1 - adjust_pads[i]);
             }
+            adjust_pads = std::vector<size_t>(pads_begin.size(), 0);
         } else {
             paddings_end = pads_end;
         }
+        ngraph::op::PadType pad_type = padMode == "VALID" ? ngraph::op::PadType::VALID : ngraph::op::PadType::EXPLICIT;
 
         auto deconv = std::make_shared<ngraph::op::v1::ConvolutionBackpropData>(
                           ieInpNode,
@@ -2355,7 +2338,10 @@ public:
                           ngraph::Strides(strides),
                           ngraph::CoordinateDiff(std::vector<std::ptrdiff_t>(pads_begin.begin(), pads_begin.end())),
                           ngraph::CoordinateDiff(std::vector<std::ptrdiff_t>(paddings_end.begin(), paddings_end.end())),
-                          ngraph::Strides(dilations));
+                          ngraph::Strides(dilations),
+                          pad_type,
+                          ngraph::CoordinateDiff(std::vector<std::ptrdiff_t>(adjust_pads.begin(), adjust_pads.end())));
+
         if (hasBias() || fusedBias)
         {
             std::vector<size_t> shape(deconv->get_shape().size(), 1);
diff --git a/modules/dnn/src/layers/layers_common.cpp b/modules/dnn/src/layers/layers_common.cpp
index f119c12ac0..78f91a69d6 100644
--- a/modules/dnn/src/layers/layers_common.cpp
+++ b/modules/dnn/src/layers/layers_common.cpp
@@ -144,26 +144,37 @@ void getStrideAndPadding(const LayerParams &params, std::vector<size_t>& pads_be
 }
 }
 
-void getPoolingKernelParams(const LayerParams &params, std::vector<size_t>& kernel, bool &globalPooling,
+void getPoolingKernelParams(const LayerParams &params, std::vector<size_t>& kernel, std::vector<bool>& globalPooling,
                             std::vector<size_t>& pads_begin, std::vector<size_t>& pads_end,
                             std::vector<size_t>& strides, cv::String &padMode)
 {
-    globalPooling = params.has("global_pooling") &&
-                    params.get<bool>("global_pooling");
+    bool is_global = params.get<bool>("global_pooling", false);
+    globalPooling.resize(3);
+    globalPooling[0] = params.get<bool>("global_pooling_d", is_global);
+    globalPooling[1] = params.get<bool>("global_pooling_h", is_global);
+    globalPooling[2] = params.get<bool>("global_pooling_w", is_global);
 
-    if (globalPooling)
+    if (globalPooling[0] || globalPooling[1] || globalPooling[2])
     {
         util::getStrideAndPadding(params, pads_begin, pads_end, strides, padMode);
-        if(params.has("kernel_h") || params.has("kernel_w") || params.has("kernel_size"))
-        {
+        if ((globalPooling[0] && params.has("kernel_d")) ||
+            (globalPooling[1] && params.has("kernel_h")) ||
+            (globalPooling[2] && params.has("kernel_w")) ||
+            params.has("kernel_size")) {
             CV_Error(cv::Error::StsBadArg, "In global_pooling mode, kernel_size (or kernel_h and kernel_w) cannot be specified");
         }
-        for (int i = 0; i < pads_begin.size(); i++) {
-            if (pads_begin[i] != 0 || pads_end[i] != 0)
+
+        kernel.resize(3);
+        kernel[0] = params.get<int>("kernel_d", 1);
+        kernel[1] = params.get<int>("kernel_h", 1);
+        kernel[2] = params.get<int>("kernel_w", 1);
+
+        for (int i = 0, j = globalPooling.size() - pads_begin.size(); i < pads_begin.size(); i++, j++) {
+            if ((pads_begin[i] != 0 || pads_end[i] != 0) && globalPooling[j])
                 CV_Error(cv::Error::StsBadArg, "In global_pooling mode, pads must be = 0");
         }
-        for (int i = 0; i < strides.size(); i++) {
-            if (strides[i] != 1)
+        for (int i = 0, j = globalPooling.size() - strides.size(); i < strides.size(); i++, j++) {
+            if (strides[i] != 1 && globalPooling[j])
                 CV_Error(cv::Error::StsBadArg, "In global_pooling mode, strides must be = 1");
         }
     }
diff --git a/modules/dnn/src/layers/layers_common.hpp b/modules/dnn/src/layers/layers_common.hpp
index b574d7eed0..81e7bdd11c 100644
--- a/modules/dnn/src/layers/layers_common.hpp
+++ b/modules/dnn/src/layers/layers_common.hpp
@@ -63,7 +63,7 @@ void getConvolutionKernelParams(const LayerParams &params, std::vector<size_t>&
                                 std::vector<size_t>& pads_end, std::vector<size_t>& strides, std::vector<size_t>& dilations,
                                 cv::String &padMode, std::vector<size_t>& adjust_pads);
 
-void getPoolingKernelParams(const LayerParams &params, std::vector<size_t>& kernel, bool &globalPooling,
+void getPoolingKernelParams(const LayerParams &params, std::vector<size_t>& kernel, std::vector<bool>& globalPooling,
                             std::vector<size_t>& pads_begin, std::vector<size_t>& pads_end, std::vector<size_t>& strides, cv::String &padMode);
 
 void getConvPoolOutParams(const std::vector<int>& inp, const std::vector<size_t>& kernel,
diff --git a/modules/dnn/src/layers/pooling_layer.cpp b/modules/dnn/src/layers/pooling_layer.cpp
index 96e150abd6..6582432600 100644
--- a/modules/dnn/src/layers/pooling_layer.cpp
+++ b/modules/dnn/src/layers/pooling_layer.cpp
@@ -89,6 +89,7 @@ public:
     {
         computeMaxIdx = true;
         globalPooling = false;
+        isGlobalPooling = std::vector<bool>(3, false);
         stride = Size(1, 1);
         pad_t = pad_l = pad_b = pad_r = 0;
 
@@ -105,7 +106,8 @@ public:
             else
                 CV_Error(Error::StsBadArg, "Unknown pooling type \"" + pool + "\"");
 
-            getPoolingKernelParams(params, kernel_size, globalPooling, pads_begin, pads_end, strides, padMode);
+            getPoolingKernelParams(params, kernel_size, isGlobalPooling, pads_begin, pads_end, strides, padMode);
+            globalPooling = isGlobalPooling[0] || isGlobalPooling[1] || isGlobalPooling[2];
             if (kernel_size.size() == 2) {
                 kernel = Size(kernel_size[1], kernel_size[0]);
                 stride = Size(strides[1], strides[0]);
@@ -157,9 +159,14 @@ public:
             out.push_back(outputs[0].size[i]);
         }
         if (globalPooling) {
-            kernel = Size(inp[1], inp[0]);
-            kernel_size = std::vector<size_t>(inp.begin(), inp.end());
-        }
+            std::vector<size_t> finalKernel;
+            for (int i = 0; i < inp.size(); i++) {
+                int idx = isGlobalPooling.size() - inp.size() + i;
+                finalKernel.push_back(isGlobalPooling[idx] ? inp[i] : kernel_size[idx]);
+             }
+             kernel_size = finalKernel;
+             kernel = Size(kernel_size[1], kernel_size[0]);
+         }
 
         getConvPoolPaddings(inp, kernel_size, strides, padMode, pads_begin, pads_end);
         if (pads_begin.size() == 2) {
@@ -1149,20 +1156,25 @@ virtual Ptr<BackendNode> initNgraph(const std::vector<Ptr<BackendWrapper> >& inp
         std::vector<int> inpShape(inputs[0].begin() + 2, inputs[0].end());
         std::vector<int> outShape(inputs[0].begin(), inputs[0].begin() + 2);
 
-        if (globalPooling)
-        {
-            outShape.push_back(1);
-            outShape.push_back(1);
+        std::vector<size_t> local_kernel;
+        if (globalPooling) {
+            for (int i = 0; i < inpShape.size(); i++) {
+                int idx = isGlobalPooling.size() - inpShape.size() + i;
+                local_kernel.push_back(isGlobalPooling[idx] ? inpShape[i] : kernel_size[idx]);
+            }
+        } else {
+            local_kernel = kernel_size;
         }
-        else if (type == ROI || type == PSROI)
+
+        if (type == ROI || type == PSROI)
         {
             outShape.push_back(pooledSize.height);
             outShape.push_back(pooledSize.width);
         }
         else if (padMode.empty())
         {
-            for (int i = 0; i < kernel_size.size(); i++) {
-                float dst = (float)(inpShape[i] + pads_begin[i] + pads_end[i] - kernel_size[i]) / strides[i];
+            for (int i = 0; i < local_kernel.size(); i++) {
+                float dst = (float)(inpShape[i] + pads_begin[i] + pads_end[i] - local_kernel[i]) / strides[i];
                 outShape.push_back(1 + (ceilMode ? ceil(dst) : floor(dst)));
             }
 
@@ -1177,7 +1189,7 @@ virtual Ptr<BackendNode> initNgraph(const std::vector<Ptr<BackendWrapper> >& inp
         }
         else
         {
-            getConvPoolOutParams(inpShape, kernel_size, strides, padMode, std::vector<size_t>(kernel_size.size(), 1), outShape);
+            getConvPoolOutParams(inpShape, local_kernel, strides, padMode, std::vector<size_t>(local_kernel.size(), 1), outShape);
         }
         if (type == ROI)
         {
diff --git a/modules/dnn/src/layers/slice_layer.cpp b/modules/dnn/src/layers/slice_layer.cpp
index 8d035fbeb8..2d70cc18c1 100644
--- a/modules/dnn/src/layers/slice_layer.cpp
+++ b/modules/dnn/src/layers/slice_layer.cpp
@@ -121,7 +121,8 @@ public:
     {
         return backendId == DNN_BACKEND_OPENCV ||
                backendId == DNN_BACKEND_CUDA ||
-               ((backendId == DNN_BACKEND_INFERENCE_ENGINE_NN_BUILDER_2019 || backendId == DNN_BACKEND_INFERENCE_ENGINE_NGRAPH) &&
+               (backendId == DNN_BACKEND_INFERENCE_ENGINE_NGRAPH && sliceRanges.size() == 1) ||
+               (backendId == DNN_BACKEND_INFERENCE_ENGINE_NN_BUILDER_2019 &&
 #ifdef HAVE_INF_ENGINE
                 INF_ENGINE_VER_MAJOR_GE(INF_ENGINE_RELEASE_2019R1) &&
 #endif
diff --git a/modules/dnn/src/layers/softmax_layer.cpp b/modules/dnn/src/layers/softmax_layer.cpp
index 500665f6d6..8e45fee1ee 100644
--- a/modules/dnn/src/layers/softmax_layer.cpp
+++ b/modules/dnn/src/layers/softmax_layer.cpp
@@ -100,7 +100,8 @@ public:
         return backendId == DNN_BACKEND_OPENCV ||
                backendId == DNN_BACKEND_CUDA ||
                (backendId == DNN_BACKEND_HALIDE && haveHalide() && axisRaw == 1) ||
-               ((backendId == DNN_BACKEND_INFERENCE_ENGINE_NN_BUILDER_2019 || backendId == DNN_BACKEND_INFERENCE_ENGINE_NGRAPH) && haveInfEngine() && !logSoftMax) ||
+               backendId == DNN_BACKEND_INFERENCE_ENGINE_NGRAPH ||
+               (backendId == DNN_BACKEND_INFERENCE_ENGINE_NN_BUILDER_2019 && haveInfEngine() && !logSoftMax) ||
                (backendId == DNN_BACKEND_VKCOM && haveVulkan());
     }
 
@@ -366,6 +367,9 @@ public:
         auto& ieInpNode = nodes[0].dynamicCast<InfEngineNgraphNode>()->node;
         int axis = clamp(axisRaw, ieInpNode->get_shape().size());
         auto softmax = std::make_shared<ngraph::op::v1::Softmax>(ieInpNode, axis);
+        if (logSoftMax)
+            return Ptr<BackendNode>(new InfEngineNgraphNode(std::make_shared<ngraph::op::v0::Log>(softmax)));
+
         return Ptr<BackendNode>(new InfEngineNgraphNode(softmax));
     }
 #endif  // HAVE_DNN_NGRAPH
diff --git a/modules/dnn/src/op_inf_engine.cpp b/modules/dnn/src/op_inf_engine.cpp
index 2036d3aa03..238b68467b 100644
--- a/modules/dnn/src/op_inf_engine.cpp
+++ b/modules/dnn/src/op_inf_engine.cpp
@@ -564,11 +564,45 @@ static std::map<std::string, InferenceEngine::InferenceEnginePluginPtr>& getShar
     return sharedPlugins;
 }
 #else
-InferenceEngine::Core& getCore()
+static bool init_IE_plugins()
+{
+    // load and hold IE plugins
+    static InferenceEngine::Core* init_core = new InferenceEngine::Core();  // 'delete' is never called
+    (void)init_core->GetAvailableDevices();
+    return true;
+}
+static InferenceEngine::Core& create_IE_Core_instance()
 {
     static InferenceEngine::Core core;
     return core;
 }
+static InferenceEngine::Core& create_IE_Core_pointer()
+{
+    // load and hold IE plugins
+    static InferenceEngine::Core* core = new InferenceEngine::Core();  // 'delete' is never called
+    return *core;
+}
+InferenceEngine::Core& getCore()
+{
+    // to make happy memory leak tools use:
+    // - OPENCV_DNN_INFERENCE_ENGINE_HOLD_PLUGINS=0
+    // - OPENCV_DNN_INFERENCE_ENGINE_CORE_LIFETIME_WORKAROUND=0
+    static bool param_DNN_INFERENCE_ENGINE_HOLD_PLUGINS = utils::getConfigurationParameterBool("OPENCV_DNN_INFERENCE_ENGINE_HOLD_PLUGINS", true);
+    static bool init_IE_plugins_ = param_DNN_INFERENCE_ENGINE_HOLD_PLUGINS && init_IE_plugins(); CV_UNUSED(init_IE_plugins_);
+
+    static bool param_DNN_INFERENCE_ENGINE_CORE_LIFETIME_WORKAROUND =
+            utils::getConfigurationParameterBool("OPENCV_DNN_INFERENCE_ENGINE_CORE_LIFETIME_WORKAROUND",
+#ifdef _WIN32
+                true
+#else
+                false
+#endif
+            );
+    static InferenceEngine::Core& core = param_DNN_INFERENCE_ENGINE_CORE_LIFETIME_WORKAROUND
+            ? create_IE_Core_pointer()
+            : create_IE_Core_instance();
+    return core;
+}
 #endif
 
 #if !defined(OPENCV_DNN_IE_VPU_TYPE_DEFAULT)
diff --git a/modules/dnn/src/tensorflow/tf_importer.cpp b/modules/dnn/src/tensorflow/tf_importer.cpp
index 80a62ccfe3..3f70636d2a 100644
--- a/modules/dnn/src/tensorflow/tf_importer.cpp
+++ b/modules/dnn/src/tensorflow/tf_importer.cpp
@@ -1936,20 +1936,22 @@ void TFImporter::populateNet(Net dstNet)
         }
         else if (type == "Mean")
         {
+            // Computes the mean of elements across dimensions of a tensor.
+            // If keepdims is false (default) reduces input_tensor along the dimensions given in axis,
+            // else the reduced dimensions are retained with length 1.
+            // if indices = [1, 2] in NHWC layout we use global pooling: NxCxHxW --Pooling--> NxCx1x1
+            // if keepdims is false we use Flatten after Pooling: out_shape = NxC
+            // if indices = [0] we use a global pooling by indices.
+            // To return correct shape, we use Reshape after Pooling. To determine input shape use Slice for input,
+            // if keepdims is false we use Flatten after Slice.
+            // Example: input_shape = NxCxHxW
+            // determine out shape: NxCxHxW --Slice--> 1xCxHxW
+            //                      out_shape = 1xCxHxW if keepDims else (1xCxHxW --Flatten--> CxHxW)
+            // global pool: NxCxHxW --Flatten--> Nx(C*H*W) --Reshape--> 1x1xNx(C*H*W) --Pooling--> 1x1x1x(C*H*W) --Reshape--> out_shape
+
             Mat indices = getTensorContent(getConstBlob(layer, value_id, 1));
             CV_Assert(indices.type() == CV_32SC1);
 
-            if (indices.total() != 2 || indices.at<int>(0) != 1 || indices.at<int>(1) != 2)
-                CV_Error(Error::StsNotImplemented, "Unsupported mode of reduce_mean operation.");
-
-            layerParams.set("pool", "ave");
-            layerParams.set("global_pooling", true);
-
-            int id = dstNet.addLayer(name, "Pooling", layerParams);
-            layer_id[name] = id;
-
-            connect(layer_id, dstNet, parsePin(layer.input(0)), id, 0);
-
             // There are two attributes, "keepdims" and a deprecated "keep_dims".
             bool keepDims = false;
             if (hasLayerAttr(layer, "keepdims"))
@@ -1957,16 +1959,128 @@ void TFImporter::populateNet(Net dstNet)
             else if (hasLayerAttr(layer, "keep_dims"))
                 keepDims = getLayerAttr(layer, "keep_dims").b();
 
-            if (!keepDims)
+            if (indices.total() == 1 && indices.at<int>(0) == 0)
             {
                 LayerParams flattenLp;
                 std::string flattenName = name + "/flatten";
                 CV_Assert(layer_id.find(flattenName) == layer_id.end());
                 int flattenId = dstNet.addLayer(flattenName, "Flatten", flattenLp);
                 layer_id[flattenName] = flattenId;
-                connect(layer_id, dstNet, Pin(name), flattenId, 0);
+                connect(layer_id, dstNet, parsePin(layer.input(0)), flattenId, 0);
+
+                LayerParams reshapeLp;
+                std::string reshapeName = name + "/reshape";
+                CV_Assert(layer_id.find(reshapeName) == layer_id.end());
+                reshapeLp.set("axis", 0);
+                reshapeLp.set("num_axes", 1);
+                int newShape[] = {1, 1, -1};
+                reshapeLp.set("dim", DictValue::arrayInt(&newShape[0], 3));
+
+                int reshapeId = dstNet.addLayer(reshapeName, "Reshape", reshapeLp);
+                layer_id[reshapeName] = reshapeId;
+                connect(layer_id, dstNet, Pin(flattenName), reshapeId, 0);
+
+                LayerParams avgLp;
+                std::string avgName = name + "/avg";
+                CV_Assert(layer_id.find(avgName) == layer_id.end());
+                avgLp.set("pool", "ave");
+                // pooling kernel H x 1
+                avgLp.set("global_pooling_h", true);
+                avgLp.set("kernel_w", 1);
+                int avgId = dstNet.addLayer(avgName, "Pooling", avgLp);
+                layer_id[avgName] = avgId;
+                connect(layer_id, dstNet, Pin(reshapeName), avgId, 0);
+
+                LayerParams sliceLp;
+                std::string layerShapeName = name + "/slice";
+                CV_Assert(layer_id.find(layerShapeName) == layer_id.end());
+                sliceLp.set("axis", 0);
+                int begin[] = {0};
+                int size[] = {1};
+                sliceLp.set("begin", DictValue::arrayInt(&begin[0], 1));
+                sliceLp.set("size", DictValue::arrayInt(&size[0], 1));
+                int sliceId = dstNet.addLayer(layerShapeName, "Slice", sliceLp);
+                layer_id[layerShapeName] = sliceId;
+                connect(layer_id, dstNet, Pin(layer.input(0)), sliceId, 0);
+
+                if (!keepDims)
+                {
+                    LayerParams squeezeLp;
+                    std::string squeezeName = name + "/squeeze";
+                    CV_Assert(layer_id.find(squeezeName) == layer_id.end());
+                    squeezeLp.set("axis", 0);
+                    squeezeLp.set("end_axis", 1);
+                    int squeezeId = dstNet.addLayer(squeezeName, "Flatten", squeezeLp);
+                    layer_id[squeezeName] = squeezeId;
+                    connect(layer_id, dstNet, Pin(layerShapeName), squeezeId, 0);
+                    layerShapeName = squeezeName;
+                }
+
+                int id = dstNet.addLayer(name, "Reshape", layerParams);
+                layer_id[name] = id;
+                connect(layer_id, dstNet, Pin(avgName), id, 0);
+                connect(layer_id, dstNet, Pin(layerShapeName), id, 1);
+            } else {
+                if (indices.total() != 2 || indices.at<int>(0) != 1 || indices.at<int>(1) != 2)
+                    CV_Error(Error::StsNotImplemented, "Unsupported mode of reduce_mean operation.");
+
+                layerParams.set("pool", "ave");
+                layerParams.set("global_pooling", true);
+                int id = dstNet.addLayer(name, "Pooling", layerParams);
+                layer_id[name] = id;
+                connect(layer_id, dstNet, parsePin(layer.input(0)), id, 0);
+
+                if (!keepDims)
+                {
+                    LayerParams flattenLp;
+                    std::string flattenName = name + "/flatten";
+                    CV_Assert(layer_id.find(flattenName) == layer_id.end());
+                    int flattenId = dstNet.addLayer(flattenName, "Flatten", flattenLp);
+                    layer_id[flattenName] = flattenId;
+                    connect(layer_id, dstNet, Pin(name), flattenId, 0);
+                }
             }
         }
+        else if (type == "Pack")
+        {
+            // op: tf.stack(list of tensors, axis=0)
+            // Join a list of inputs along a new axis.
+            // The "axis" specifies the index of the new axis in the dimensions of the output.
+            // Example: given a list with "N" tensors of shape (C, H, W):
+            // if axis == 0 then the output tensor will have the shape (N, C, H, W),
+            // if axis == 1 then the output tensor will have the shape (C, N, H, W).
+            CV_Assert(hasLayerAttr(layer, "axis"));
+            int dim = (int)getLayerAttr(layer, "axis").i();
+            if (dim != 0)
+                CV_Error(Error::StsNotImplemented, "Unsupported mode of pack operation.");
+
+            CV_Assert(hasLayerAttr(layer, "N"));
+            int num = (int)getLayerAttr(layer, "N").i();
+            CV_Assert(layer.input_size() == num);
+            std::string base_name = name + "/reshape_";
+            std::vector<int> reshape_ids;
+            for (int i = 0; i < num; i++) {
+                std::ostringstream ss;
+                ss << i;
+                std::string reshape_name = base_name + ss.str();
+                LayerParams reshapeLP;
+                reshapeLP.set("axis", dim);
+                reshapeLP.set("num_axes", 1);
+                int outShape[] = {1, -1};
+                reshapeLP.set("dim", DictValue::arrayInt(&outShape[0], 2));
+                int id = dstNet.addLayer(reshape_name, "Reshape", reshapeLP);
+                layer_id[reshape_name] = id;
+                reshape_ids.push_back(id);
+                connect(layer_id, dstNet, parsePin(layer.input(i)), id, 0);
+            }
+
+            layerParams.set("axis", dim);
+            int id = dstNet.addLayer(name, "Concat", layerParams);
+            layer_id[name] = id;
+
+            for (int li = 0; li < num; li++)
+                dstNet.connect(reshape_ids[li], 0, id, li);
+        }
         else if (type == "ClipByValue")
         {
             // op: "ClipByValue"
diff --git a/modules/dnn/test/test_tf_importer.cpp b/modules/dnn/test/test_tf_importer.cpp
index 621c31c007..6a5523214a 100644
--- a/modules/dnn/test/test_tf_importer.cpp
+++ b/modules/dnn/test/test_tf_importer.cpp
@@ -121,6 +121,13 @@ public:
     }
 };
 
+TEST_P(Test_TensorFlow_layers, reduce_mean)
+{
+    if (backend == DNN_BACKEND_INFERENCE_ENGINE_NN_BUILDER_2019)
+        applyTestTag(CV_TEST_TAG_DNN_SKIP_IE_NN_BUILDER);
+    runTensorFlowNet("global_pool_by_axis");
+}
+
 TEST_P(Test_TensorFlow_layers, conv)
 {
     runTensorFlowNet("single_conv");
diff --git a/modules/imgproc/CMakeLists.txt b/modules/imgproc/CMakeLists.txt
index 0c7b3268df..bf66abb59f 100644
--- a/modules/imgproc/CMakeLists.txt
+++ b/modules/imgproc/CMakeLists.txt
@@ -9,4 +9,5 @@ ocv_add_dispatched_file(color_yuv SSE2 SSE4_1 AVX2)
 ocv_add_dispatched_file(median_blur SSE2 SSE4_1 AVX2)
 ocv_add_dispatched_file(morph SSE2 SSE4_1 AVX2)
 ocv_add_dispatched_file(smooth SSE2 SSE4_1 AVX2)
+ocv_add_dispatched_file(sumpixels SSE2 AVX2 AVX512_SKX)
 ocv_define_module(imgproc opencv_core WRAP java python js)
diff --git a/modules/imgproc/src/sumpixels.avx512_skx.cpp b/modules/imgproc/src/sumpixels.avx512_skx.hpp
similarity index 98%
rename from modules/imgproc/src/sumpixels.avx512_skx.cpp
rename to modules/imgproc/src/sumpixels.avx512_skx.hpp
index 804b48d8c5..3c9c90c658 100644
--- a/modules/imgproc/src/sumpixels.avx512_skx.cpp
+++ b/modules/imgproc/src/sumpixels.avx512_skx.hpp
@@ -2,14 +2,13 @@
 // It is subject to the license terms in the LICENSE file found in the top-level directory
 // of this distribution and at http://opencv.org/license.html.
 //
-// Copyright (C) 2019, Intel Corporation, all rights reserved.
-#include "precomp.hpp"
-#include "sumpixels.hpp"
+// Copyright (C) 2019-2020, Intel Corporation, all rights reserved.
 
 #include "opencv2/core/hal/intrin.hpp"
 
+namespace cv { namespace hal {
+CV_CPU_OPTIMIZATION_NAMESPACE_BEGIN
 
-namespace cv {
 namespace { // Anonymous namespace to avoid exposing the implementation classes
 
 //
@@ -432,16 +431,14 @@ __m512d IntegralCalculator < 4 > ::calculate_integral(const __m512i src_longs, c
 
 } // end of anonymous namespace
 
-namespace opt_AVX512_SKX {
-
-// This is the implementation for the external callers interface entry point.
-// It should be the only function called into this file from outside
-// Any new implementations should be directed from here
+static
 void calculate_integral_avx512(const uchar *src,   size_t _srcstep,
                                double      *sum,   size_t _sumstep,
                                double      *sqsum, size_t _sqsumstep,
                                int width, int height, int cn)
 {
+    CV_INSTRUMENT_REGION();
+
     switch(cn){
         case 1: {
             IntegralCalculator< 1 > calculator;
@@ -466,5 +463,5 @@ void calculate_integral_avx512(const uchar *src,   size_t _srcstep,
 }
 
 
-} // end namespace opt_AVX512_SXK
-} // end namespace cv
+CV_CPU_OPTIMIZATION_NAMESPACE_END
+}} // end namespace cv::hal
diff --git a/modules/imgproc/src/sumpixels.cpp b/modules/imgproc/src/sumpixels.dispatch.cpp
similarity index 67%
rename from modules/imgproc/src/sumpixels.cpp
rename to modules/imgproc/src/sumpixels.dispatch.cpp
index 89337f3507..b828ec70c0 100755
--- a/modules/imgproc/src/sumpixels.cpp
+++ b/modules/imgproc/src/sumpixels.dispatch.cpp
@@ -10,7 +10,7 @@
 //                           License Agreement
 //                For Open Source Computer Vision Library
 //
-// Copyright (C) 2000-2008,2019 Intel Corporation, all rights reserved.
+// Copyright (C) 2000-2020 Intel Corporation, all rights reserved.
 // Copyright (C) 2009, Willow Garage Inc., all rights reserved.
 // Copyright (C) 2014, Itseez Inc., all rights reserved.
 // Third party copyrights are property of their respective owners.
@@ -44,210 +44,157 @@
 #include "precomp.hpp"
 #include "opencl_kernels_imgproc.hpp"
 #include "opencv2/core/hal/intrin.hpp"
-#include "sumpixels.hpp"
 
-namespace cv
-{
+#include "sumpixels.simd.hpp"
+#include "sumpixels.simd_declarations.hpp" // defines CV_CPU_DISPATCH_MODES_ALL=AVX2,...,BASELINE based on CMakeLists.txt content
+
+
+namespace cv {
+
+#ifdef HAVE_OPENCL
 
-template <typename T, typename ST, typename QT>
-struct Integral_SIMD
+static bool ocl_integral( InputArray _src, OutputArray _sum, int sdepth )
 {
-    bool operator()(const T *, size_t,
-                    ST *, size_t,
-                    QT *, size_t,
-                    ST *, size_t,
-                    int, int, int) const
-    {
+    bool doubleSupport = ocl::Device::getDefault().doubleFPConfig() > 0;
+
+    if ( (_src.type() != CV_8UC1) ||
+        !(sdepth == CV_32S || sdepth == CV_32F || (doubleSupport && sdepth == CV_64F)))
         return false;
-    }
-};
 
+    static const int tileSize = 16;
 
-template <>
-struct Integral_SIMD<uchar, double, double> {
-    Integral_SIMD() {};
+    String build_opt = format("-D sumT=%s -D LOCAL_SUM_SIZE=%d%s",
+                                ocl::typeToStr(sdepth), tileSize,
+                                doubleSupport ? " -D DOUBLE_SUPPORT" : "");
 
+    ocl::Kernel kcols("integral_sum_cols", ocl::imgproc::integral_sum_oclsrc, build_opt);
+    if (kcols.empty())
+        return false;
 
-    bool operator()(const uchar *src, size_t _srcstep,
-                    double *sum,      size_t _sumstep,
-                    double *sqsum,    size_t _sqsumstep,
-                    double *tilted,   size_t _tiltedstep,
-                    int width, int height, int cn) const
-    {
-#if CV_TRY_AVX512_SKX
-        CV_UNUSED(_tiltedstep);
-        // TODO:  Add support for 1 channel input (WIP)
-        if (CV_CPU_HAS_SUPPORT_AVX512_SKX && !tilted && (cn <= 4)){
-            opt_AVX512_SKX::calculate_integral_avx512(src, _srcstep, sum, _sumstep,
-                                                      sqsum, _sqsumstep, width, height, cn);
-            return true;
-        }
-#else
-        // Avoid warnings in some builds
-        CV_UNUSED(src); CV_UNUSED(_srcstep); CV_UNUSED(sum); CV_UNUSED(_sumstep);
-        CV_UNUSED(sqsum); CV_UNUSED(_sqsumstep); CV_UNUSED(tilted); CV_UNUSED(_tiltedstep);
-        CV_UNUSED(width); CV_UNUSED(height); CV_UNUSED(cn);
-#endif
+    UMat src = _src.getUMat();
+    Size src_size = src.size();
+    Size bufsize(((src_size.height + tileSize - 1) / tileSize) * tileSize, ((src_size.width + tileSize - 1) / tileSize) * tileSize);
+    UMat buf(bufsize, sdepth);
+    kcols.args(ocl::KernelArg::ReadOnly(src), ocl::KernelArg::WriteOnlyNoSize(buf));
+    size_t gt = src.cols, lt = tileSize;
+    if (!kcols.run(1, &gt, &lt, false))
         return false;
-    }
 
-};
+    ocl::Kernel krows("integral_sum_rows", ocl::imgproc::integral_sum_oclsrc, build_opt);
+    if (krows.empty())
+        return false;
 
-#if CV_SIMD && CV_SIMD_WIDTH <= 64
+    Size sumsize(src_size.width + 1, src_size.height + 1);
+    _sum.create(sumsize, sdepth);
+    UMat sum = _sum.getUMat();
 
-template <>
-struct Integral_SIMD<uchar, int, double>
-{
-    Integral_SIMD() {}
+    krows.args(ocl::KernelArg::ReadOnlyNoSize(buf), ocl::KernelArg::WriteOnly(sum));
+    gt = src.rows;
+    return krows.run(1, &gt, &lt, false);
+}
 
-    bool operator()(const uchar * src, size_t _srcstep,
-                    int * sum, size_t _sumstep,
-                    double * sqsum, size_t,
-                    int * tilted, size_t,
-                    int width, int height, int cn) const
-    {
-        if (sqsum || tilted || cn != 1)
-            return false;
+static bool ocl_integral( InputArray _src, OutputArray _sum, OutputArray _sqsum, int sdepth, int sqdepth )
+{
+    bool doubleSupport = ocl::Device::getDefault().doubleFPConfig() > 0;
 
-        // the first iteration
-        memset(sum, 0, (width + 1) * sizeof(int));
+    if ( _src.type() != CV_8UC1 || (!doubleSupport && (sdepth == CV_64F || sqdepth == CV_64F)) )
+        return false;
 
-        // the others
-        for (int i = 0; i < height; ++i)
-        {
-            const uchar * src_row = src + _srcstep * i;
-            int * prev_sum_row = (int *)((uchar *)sum + _sumstep * i) + 1;
-            int * sum_row = (int *)((uchar *)sum + _sumstep * (i + 1)) + 1;
+    static const int tileSize = 16;
 
-            sum_row[-1] = 0;
+    String build_opt = format("-D SUM_SQUARE -D sumT=%s -D sumSQT=%s -D LOCAL_SUM_SIZE=%d%s",
+                                ocl::typeToStr(sdepth), ocl::typeToStr(sqdepth),
+                                tileSize,
+                                doubleSupport ? " -D DOUBLE_SUPPORT" : "");
 
-            v_int32 prev = vx_setzero_s32();
-            int j = 0;
-            for ( ; j + v_uint16::nlanes <= width; j += v_uint16::nlanes)
-            {
-                v_int16 el8 = v_reinterpret_as_s16(vx_load_expand(src_row + j));
-                v_int32 el4l, el4h;
-#if CV_AVX2 && CV_SIMD_WIDTH == 32
-                __m256i vsum = _mm256_add_epi16(el8.val, _mm256_slli_si256(el8.val, 2));
-                vsum = _mm256_add_epi16(vsum, _mm256_slli_si256(vsum, 4));
-                vsum = _mm256_add_epi16(vsum, _mm256_slli_si256(vsum, 8));
-                __m256i shmask = _mm256_set1_epi32(7);
-                el4l.val = _mm256_add_epi32(_mm256_cvtepi16_epi32(_v256_extract_low(vsum)), prev.val);
-                el4h.val = _mm256_add_epi32(_mm256_cvtepi16_epi32(_v256_extract_high(vsum)), _mm256_permutevar8x32_epi32(el4l.val, shmask));
-                prev.val = _mm256_permutevar8x32_epi32(el4h.val, shmask);
-#else
-                el8 += v_rotate_left<1>(el8);
-                el8 += v_rotate_left<2>(el8);
-#if CV_SIMD_WIDTH >= 32
-                el8 += v_rotate_left<4>(el8);
-#if CV_SIMD_WIDTH == 64
-                el8 += v_rotate_left<8>(el8);
-#endif
-#endif
-                v_expand(el8, el4l, el4h);
-                el4l += prev;
-                el4h += el4l;
-
-                prev = v_broadcast_element<v_int32::nlanes - 1>(el4h);
-#endif
-                v_store(sum_row + j                  , el4l + vx_load(prev_sum_row + j                  ));
-                v_store(sum_row + j + v_int32::nlanes, el4h + vx_load(prev_sum_row + j + v_int32::nlanes));
-            }
+    ocl::Kernel kcols("integral_sum_cols", ocl::imgproc::integral_sum_oclsrc, build_opt);
+    if (kcols.empty())
+        return false;
 
-            for (int v = sum_row[j - 1] - prev_sum_row[j - 1]; j < width; ++j)
-                sum_row[j] = (v += src_row[j]) + prev_sum_row[j];
-        }
-        vx_cleanup();
+    UMat src = _src.getUMat();
+    Size src_size = src.size();
+    Size bufsize(((src_size.height + tileSize - 1) / tileSize) * tileSize, ((src_size.width + tileSize - 1) / tileSize) * tileSize);
+    UMat buf(bufsize, sdepth);
+    UMat buf_sq(bufsize, sqdepth);
+    kcols.args(ocl::KernelArg::ReadOnly(src), ocl::KernelArg::WriteOnlyNoSize(buf), ocl::KernelArg::WriteOnlyNoSize(buf_sq));
+    size_t gt = src.cols, lt = tileSize;
+    if (!kcols.run(1, &gt, &lt, false))
+        return false;
 
-        return true;
-    }
-};
+    ocl::Kernel krows("integral_sum_rows", ocl::imgproc::integral_sum_oclsrc, build_opt);
+    if (krows.empty())
+        return false;
 
-template <>
-struct Integral_SIMD<uchar, float, double>
-{
-    Integral_SIMD() {}
+    Size sumsize(src_size.width + 1, src_size.height + 1);
+    _sum.create(sumsize, sdepth);
+    UMat sum = _sum.getUMat();
+    _sqsum.create(sumsize, sqdepth);
+    UMat sum_sq = _sqsum.getUMat();
 
-    bool operator()(const uchar * src, size_t _srcstep,
-        float * sum, size_t _sumstep,
-        double * sqsum, size_t,
-        float * tilted, size_t,
-        int width, int height, int cn) const
-    {
-        if (sqsum || tilted || cn != 1)
-            return false;
+    krows.args(ocl::KernelArg::ReadOnlyNoSize(buf), ocl::KernelArg::ReadOnlyNoSize(buf_sq), ocl::KernelArg::WriteOnly(sum), ocl::KernelArg::WriteOnlyNoSize(sum_sq));
+    gt = src.rows;
+    return krows.run(1, &gt, &lt, false);
+}
 
-        // the first iteration
-        memset(sum, 0, (width + 1) * sizeof(int));
+#endif  // HAVE_OPENCL
 
-        // the others
-        for (int i = 0; i < height; ++i)
-        {
-            const uchar * src_row = src + _srcstep * i;
-            float * prev_sum_row = (float *)((uchar *)sum + _sumstep * i) + 1;
-            float * sum_row = (float *)((uchar *)sum + _sumstep * (i + 1)) + 1;
+#ifdef HAVE_IPP
 
-            sum_row[-1] = 0;
+static bool ipp_integral(
+    int depth, int sdepth, int sqdepth,
+    const uchar* src, size_t srcstep,
+    uchar* sum, size_t sumstep,
+    uchar* sqsum, size_t sqsumstep,
+    uchar* tilted, size_t tstep,
+    int width, int height, int cn)
+{
+    CV_INSTRUMENT_REGION_IPP();
 
-            v_float32 prev = vx_setzero_f32();
-            int j = 0;
-            for (; j + v_uint16::nlanes <= width; j += v_uint16::nlanes)
-            {
-                v_int16 el8 = v_reinterpret_as_s16(vx_load_expand(src_row + j));
-                v_float32 el4l, el4h;
-#if CV_AVX2 && CV_SIMD_WIDTH == 32
-                __m256i vsum = _mm256_add_epi16(el8.val, _mm256_slli_si256(el8.val, 2));
-                vsum = _mm256_add_epi16(vsum, _mm256_slli_si256(vsum, 4));
-                vsum = _mm256_add_epi16(vsum, _mm256_slli_si256(vsum, 8));
-                __m256i shmask = _mm256_set1_epi32(7);
-                el4l.val = _mm256_add_ps(_mm256_cvtepi32_ps(_mm256_cvtepi16_epi32(_v256_extract_low(vsum))), prev.val);
-                el4h.val = _mm256_add_ps(_mm256_cvtepi32_ps(_mm256_cvtepi16_epi32(_v256_extract_high(vsum))), _mm256_permutevar8x32_ps(el4l.val, shmask));
-                prev.val = _mm256_permutevar8x32_ps(el4h.val, shmask);
-#else
-                el8 += v_rotate_left<1>(el8);
-                el8 += v_rotate_left<2>(el8);
-#if CV_SIMD_WIDTH >= 32
-                el8 += v_rotate_left<4>(el8);
-#if CV_SIMD_WIDTH == 64
-                el8 += v_rotate_left<8>(el8);
-#endif
-#endif
-                v_int32 el4li, el4hi;
-                v_expand(el8, el4li, el4hi);
-                el4l = v_cvt_f32(el4li) + prev;
-                el4h = v_cvt_f32(el4hi) + el4l;
-
-                prev = v_broadcast_element<v_float32::nlanes - 1>(el4h);
-#endif
-                v_store(sum_row + j                    , el4l + vx_load(prev_sum_row + j                    ));
-                v_store(sum_row + j + v_float32::nlanes, el4h + vx_load(prev_sum_row + j + v_float32::nlanes));
-            }
+    IppiSize size = {width, height};
 
-            for (float v = sum_row[j - 1] - prev_sum_row[j - 1]; j < width; ++j)
-                sum_row[j] = (v += src_row[j]) + prev_sum_row[j];
-        }
-        vx_cleanup();
+    if(cn > 1)
+        return false;
+    if(tilted)
+    {
+        CV_UNUSED(tstep);
+        return false;
+    }
 
-        return true;
+    if(!sqsum)
+    {
+        if(depth == CV_8U && sdepth == CV_32S)
+            return CV_INSTRUMENT_FUN_IPP(ippiIntegral_8u32s_C1R, (const Ipp8u*)src, (int)srcstep, (Ipp32s*)sum, (int)sumstep, size, 0) >= 0;
+        else if(depth == CV_8UC1 && sdepth == CV_32F)
+            return CV_INSTRUMENT_FUN_IPP(ippiIntegral_8u32f_C1R, (const Ipp8u*)src, (int)srcstep, (Ipp32f*)sum, (int)sumstep, size, 0) >= 0;
+        else if(depth == CV_32FC1 && sdepth == CV_32F)
+            return CV_INSTRUMENT_FUN_IPP(ippiIntegral_32f_C1R, (const Ipp32f*)src, (int)srcstep, (Ipp32f*)sum, (int)sumstep, size) >= 0;
+        else
+            return false;
     }
-};
+    else
+    {
+        if(depth == CV_8U && sdepth == CV_32S && sqdepth == CV_32S)
+            return CV_INSTRUMENT_FUN_IPP(ippiSqrIntegral_8u32s_C1R, (const Ipp8u*)src, (int)srcstep, (Ipp32s*)sum, (int)sumstep, (Ipp32s*)sqsum, (int)sqsumstep, size, 0, 0) >= 0;
+        else if(depth == CV_8U && sdepth == CV_32S && sqdepth == CV_64F)
+            return CV_INSTRUMENT_FUN_IPP(ippiSqrIntegral_8u32s64f_C1R, (const Ipp8u*)src, (int)srcstep, (Ipp32s*)sum, (int)sumstep, (Ipp64f*)sqsum, (int)sqsumstep, size, 0, 0) >= 0;
+        else if(depth == CV_8U && sdepth == CV_32F && sqdepth == CV_64F)
+            return CV_INSTRUMENT_FUN_IPP(ippiSqrIntegral_8u32f64f_C1R, (const Ipp8u*)src, (int)srcstep, (Ipp32f*)sum, (int)sumstep, (Ipp64f*)sqsum, (int)sqsumstep, size, 0, 0) >= 0;
+        else
+            return false;
+    }
+}
 
-#endif
+#endif  // HAVE_IPP
 
-template<typename T, typename ST, typename QT>
+namespace hal {
+
+template<typename T, typename ST, typename QT> static
 void integral_( const T* src, size_t _srcstep, ST* sum, size_t _sumstep,
                 QT* sqsum, size_t _sqsumstep, ST* tilted, size_t _tiltedstep,
                 int width, int height, int cn )
 {
     int x, y, k;
 
-    if (Integral_SIMD<T, ST, QT>()(src, _srcstep,
-                                   sum, _sumstep,
-                                   sqsum, _sqsumstep,
-                                   tilted, _tiltedstep,
-                                   width, height, cn))
-        return;
-
     int srcstep = (int)(_srcstep/sizeof(T));
     int sumstep = (int)(_sumstep/sizeof(ST));
     int tiltedstep = (int)(_tiltedstep/sizeof(ST));
@@ -401,157 +348,36 @@ void integral_( const T* src, size_t _srcstep, ST* sum, size_t _sumstep,
     }
 }
 
-
-#ifdef HAVE_OPENCL
-
-static bool ocl_integral( InputArray _src, OutputArray _sum, int sdepth )
-{
-    bool doubleSupport = ocl::Device::getDefault().doubleFPConfig() > 0;
-
-    if ( (_src.type() != CV_8UC1) ||
-        !(sdepth == CV_32S || sdepth == CV_32F || (doubleSupport && sdepth == CV_64F)))
-        return false;
-
-    static const int tileSize = 16;
-
-    String build_opt = format("-D sumT=%s -D LOCAL_SUM_SIZE=%d%s",
-                                ocl::typeToStr(sdepth), tileSize,
-                                doubleSupport ? " -D DOUBLE_SUPPORT" : "");
-
-    ocl::Kernel kcols("integral_sum_cols", ocl::imgproc::integral_sum_oclsrc, build_opt);
-    if (kcols.empty())
-        return false;
-
-    UMat src = _src.getUMat();
-    Size src_size = src.size();
-    Size bufsize(((src_size.height + tileSize - 1) / tileSize) * tileSize, ((src_size.width + tileSize - 1) / tileSize) * tileSize);
-    UMat buf(bufsize, sdepth);
-    kcols.args(ocl::KernelArg::ReadOnly(src), ocl::KernelArg::WriteOnlyNoSize(buf));
-    size_t gt = src.cols, lt = tileSize;
-    if (!kcols.run(1, &gt, &lt, false))
-        return false;
-
-    ocl::Kernel krows("integral_sum_rows", ocl::imgproc::integral_sum_oclsrc, build_opt);
-    if (krows.empty())
-        return false;
-
-    Size sumsize(src_size.width + 1, src_size.height + 1);
-    _sum.create(sumsize, sdepth);
-    UMat sum = _sum.getUMat();
-
-    krows.args(ocl::KernelArg::ReadOnlyNoSize(buf), ocl::KernelArg::WriteOnly(sum));
-    gt = src.rows;
-    return krows.run(1, &gt, &lt, false);
-}
-
-static bool ocl_integral( InputArray _src, OutputArray _sum, OutputArray _sqsum, int sdepth, int sqdepth )
+static bool integral_SIMD(
+        int depth, int sdepth, int sqdepth,
+        const uchar* src, size_t srcstep,
+        uchar* sum, size_t sumstep,
+        uchar* sqsum, size_t sqsumstep,
+        uchar* tilted, size_t tstep,
+        int width, int height, int cn)
 {
-    bool doubleSupport = ocl::Device::getDefault().doubleFPConfig() > 0;
-
-    if ( _src.type() != CV_8UC1 || (!doubleSupport && (sdepth == CV_64F || sqdepth == CV_64F)) )
-        return false;
-
-    static const int tileSize = 16;
-
-    String build_opt = format("-D SUM_SQUARE -D sumT=%s -D sumSQT=%s -D LOCAL_SUM_SIZE=%d%s",
-                                ocl::typeToStr(sdepth), ocl::typeToStr(sqdepth),
-                                tileSize,
-                                doubleSupport ? " -D DOUBLE_SUPPORT" : "");
-
-    ocl::Kernel kcols("integral_sum_cols", ocl::imgproc::integral_sum_oclsrc, build_opt);
-    if (kcols.empty())
-        return false;
-
-    UMat src = _src.getUMat();
-    Size src_size = src.size();
-    Size bufsize(((src_size.height + tileSize - 1) / tileSize) * tileSize, ((src_size.width + tileSize - 1) / tileSize) * tileSize);
-    UMat buf(bufsize, sdepth);
-    UMat buf_sq(bufsize, sqdepth);
-    kcols.args(ocl::KernelArg::ReadOnly(src), ocl::KernelArg::WriteOnlyNoSize(buf), ocl::KernelArg::WriteOnlyNoSize(buf_sq));
-    size_t gt = src.cols, lt = tileSize;
-    if (!kcols.run(1, &gt, &lt, false))
-        return false;
-
-    ocl::Kernel krows("integral_sum_rows", ocl::imgproc::integral_sum_oclsrc, build_opt);
-    if (krows.empty())
-        return false;
-
-    Size sumsize(src_size.width + 1, src_size.height + 1);
-    _sum.create(sumsize, sdepth);
-    UMat sum = _sum.getUMat();
-    _sqsum.create(sumsize, sqdepth);
-    UMat sum_sq = _sqsum.getUMat();
-
-    krows.args(ocl::KernelArg::ReadOnlyNoSize(buf), ocl::KernelArg::ReadOnlyNoSize(buf_sq), ocl::KernelArg::WriteOnly(sum), ocl::KernelArg::WriteOnlyNoSize(sum_sq));
-    gt = src.rows;
-    return krows.run(1, &gt, &lt, false);
-}
-
-#endif
+    CV_INSTRUMENT_REGION();
 
+    CV_CPU_DISPATCH(integral_SIMD, (depth, sdepth, sqdepth, src, srcstep, sum, sumstep, sqsum, sqsumstep, tilted, tstep, width, height, cn),
+        CV_CPU_DISPATCH_MODES_ALL);
 }
 
-#if defined(HAVE_IPP)
-namespace cv
+void integral(
+        int depth, int sdepth, int sqdepth,
+        const uchar* src, size_t srcstep,
+        uchar* sum, size_t sumstep,
+        uchar* sqsum, size_t sqsumstep,
+        uchar* tilted, size_t tstep,
+        int width, int height, int cn)
 {
-static bool ipp_integral(
-    int depth, int sdepth, int sqdepth,
-    const uchar* src, size_t srcstep,
-    uchar* sum, size_t sumstep,
-    uchar* sqsum, size_t sqsumstep,
-    uchar* tilted, size_t tstep,
-    int width, int height, int cn)
-{
-    CV_INSTRUMENT_REGION_IPP();
-
-    IppiSize size = {width, height};
-
-    if(cn > 1)
-        return false;
-    if(tilted)
-    {
-        CV_UNUSED(tstep);
-        return false;
-    }
-
-    if(!sqsum)
-    {
-        if(depth == CV_8U && sdepth == CV_32S)
-            return CV_INSTRUMENT_FUN_IPP(ippiIntegral_8u32s_C1R, (const Ipp8u*)src, (int)srcstep, (Ipp32s*)sum, (int)sumstep, size, 0) >= 0;
-        else if(depth == CV_8UC1 && sdepth == CV_32F)
-            return CV_INSTRUMENT_FUN_IPP(ippiIntegral_8u32f_C1R, (const Ipp8u*)src, (int)srcstep, (Ipp32f*)sum, (int)sumstep, size, 0) >= 0;
-        else if(depth == CV_32FC1 && sdepth == CV_32F)
-            return CV_INSTRUMENT_FUN_IPP(ippiIntegral_32f_C1R, (const Ipp32f*)src, (int)srcstep, (Ipp32f*)sum, (int)sumstep, size) >= 0;
-        else
-            return false;
-    }
-    else
-    {
-        if(depth == CV_8U && sdepth == CV_32S && sqdepth == CV_32S)
-            return CV_INSTRUMENT_FUN_IPP(ippiSqrIntegral_8u32s_C1R, (const Ipp8u*)src, (int)srcstep, (Ipp32s*)sum, (int)sumstep, (Ipp32s*)sqsum, (int)sqsumstep, size, 0, 0) >= 0;
-        else if(depth == CV_8U && sdepth == CV_32S && sqdepth == CV_64F)
-            return CV_INSTRUMENT_FUN_IPP(ippiSqrIntegral_8u32s64f_C1R, (const Ipp8u*)src, (int)srcstep, (Ipp32s*)sum, (int)sumstep, (Ipp64f*)sqsum, (int)sqsumstep, size, 0, 0) >= 0;
-        else if(depth == CV_8U && sdepth == CV_32F && sqdepth == CV_64F)
-            return CV_INSTRUMENT_FUN_IPP(ippiSqrIntegral_8u32f64f_C1R, (const Ipp8u*)src, (int)srcstep, (Ipp32f*)sum, (int)sumstep, (Ipp64f*)sqsum, (int)sqsumstep, size, 0, 0) >= 0;
-        else
-            return false;
-    }
-}
-}
-#endif
-
-namespace cv { namespace hal {
+    CV_INSTRUMENT_REGION();
 
-void integral(int depth, int sdepth, int sqdepth,
-              const uchar* src, size_t srcstep,
-              uchar* sum, size_t sumstep,
-              uchar* sqsum, size_t sqsumstep,
-              uchar* tilted, size_t tstep,
-              int width, int height, int cn)
-{
     CALL_HAL(integral, cv_hal_integral, depth, sdepth, sqdepth, src, srcstep, sum, sumstep, sqsum, sqsumstep, tilted, tstep, width, height, cn);
     CV_IPP_RUN_FAST(ipp_integral(depth, sdepth, sqdepth, src, srcstep, sum, sumstep, sqsum, sqsumstep, tilted, tstep, width, height, cn));
 
+    if (integral_SIMD(depth, sdepth, sqdepth, src, srcstep, sum, sumstep, sqsum, sqsumstep, tilted, tstep, width, height, cn))
+        return;
+
 #define ONE_CALL(A, B, C) integral_<A, B, C>((const A*)src, srcstep, (B*)sum, sumstep, (C*)sqsum, sqsumstep, (B*)tilted, tstep, width, height, cn)
 
     if( depth == CV_8U && sdepth == CV_32S && sqdepth == CV_64F )
@@ -579,14 +405,14 @@ void integral(int depth, int sdepth, int sqdepth,
     else if( depth == CV_64F && sdepth == CV_64F && sqdepth == CV_64F )
         ONE_CALL(double, double, double);
     else
-        CV_Error( CV_StsUnsupportedFormat, "" );
+        CV_Error(Error::StsUnsupportedFormat, "");
 
 #undef ONE_CALL
 }
 
-}} // cv::hal::
+} // namespace hal
 
-void cv::integral( InputArray _src, OutputArray _sum, OutputArray _sqsum, OutputArray _tilted, int sdepth, int sqdepth )
+void integral(InputArray _src, OutputArray _sum, OutputArray _sqsum, OutputArray _tilted, int sdepth, int sqdepth )
 {
     CV_INSTRUMENT_REGION();
 
@@ -624,20 +450,21 @@ void cv::integral( InputArray _src, OutputArray _sum, OutputArray _sqsum, Output
                   src.cols, src.rows, cn);
 }
 
-void cv::integral( InputArray src, OutputArray sum, int sdepth )
+void integral( InputArray src, OutputArray sum, int sdepth )
 {
     CV_INSTRUMENT_REGION();
 
     integral( src, sum, noArray(), noArray(), sdepth );
 }
 
-void cv::integral( InputArray src, OutputArray sum, OutputArray sqsum, int sdepth, int sqdepth )
+void integral( InputArray src, OutputArray sum, OutputArray sqsum, int sdepth, int sqdepth )
 {
     CV_INSTRUMENT_REGION();
 
     integral( src, sum, sqsum, noArray(), sdepth, sqdepth );
 }
 
+} // namespace
 
 CV_IMPL void
 cvIntegral( const CvArr* image, CvArr* sumImage,
diff --git a/modules/imgproc/src/sumpixels.hpp b/modules/imgproc/src/sumpixels.hpp
deleted file mode 100644
index 8d5ab0a851..0000000000
--- a/modules/imgproc/src/sumpixels.hpp
+++ /dev/null
@@ -1,25 +0,0 @@
-// This file is part of OpenCV project.
-// It is subject to the license terms in the LICENSE file found in the top-level directory
-// of this distribution and at http://opencv.org/license.html.
-//
-// Copyright (C) 2019, Intel Corporation, all rights reserved.
-#ifndef OPENCV_IMGPROC_SUM_PIXELS_HPP
-#define OPENCV_IMGPROC_SUM_PIXELS_HPP
-
-namespace cv
-{
-
-namespace opt_AVX512_SKX
-{
-#if CV_TRY_AVX512_SKX
-    void calculate_integral_avx512(
-            const uchar *src, size_t _srcstep,
-            double *sum,      size_t _sumstep,
-            double *sqsum,    size_t _sqsumstep,
-            int width, int height, int cn);
-
-#endif
-} // end namespace opt_AVX512_SKX
-} // end namespace cv
-
-#endif
diff --git a/modules/imgproc/src/sumpixels.simd.hpp b/modules/imgproc/src/sumpixels.simd.hpp
new file mode 100644
index 0000000000..c8d60a0040
--- /dev/null
+++ b/modules/imgproc/src/sumpixels.simd.hpp
@@ -0,0 +1,288 @@
+/*M///////////////////////////////////////////////////////////////////////////////////////
+//
+//  IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
+//
+//  By downloading, copying, installing or using the software you agree to this license.
+//  If you do not agree to this license, do not download, install,
+//  copy or use the software.
+//
+//
+//                           License Agreement
+//                For Open Source Computer Vision Library
+//
+// Copyright (C) 2000-2020 Intel Corporation, all rights reserved.
+// Copyright (C) 2009, Willow Garage Inc., all rights reserved.
+// Copyright (C) 2014, Itseez Inc., all rights reserved.
+// Third party copyrights are property of their respective owners.
+//
+// Redistribution and use in source and binary forms, with or without modification,
+// are permitted provided that the following conditions are met:
+//
+//   * Redistribution's of source code must retain the above copyright notice,
+//     this list of conditions and the following disclaimer.
+//
+//   * Redistribution's in binary form must reproduce the above copyright notice,
+//     this list of conditions and the following disclaimer in the documentation
+//     and/or other materials provided with the distribution.
+//
+//   * The name of the copyright holders may not be used to endorse or promote products
+//     derived from this software without specific prior written permission.
+//
+// This software is provided by the copyright holders and contributors "as is" and
+// any express or implied warranties, including, but not limited to, the implied
+// warranties of merchantability and fitness for a particular purpose are disclaimed.
+// In no event shall the Intel Corporation or contributors be liable for any direct,
+// indirect, incidental, special, exemplary, or consequential damages
+// (including, but not limited to, procurement of substitute goods or services;
+// loss of use, data, or profits; or business interruption) however caused
+// and on any theory of liability, whether in contract, strict liability,
+// or tort (including negligence or otherwise) arising in any way out of
+// the use of this software, even if advised of the possibility of such damage.
+//
+//M*/
+
+#include "opencv2/core/hal/intrin.hpp"
+
+#if CV_AVX512_SKX
+#include "sumpixels.avx512_skx.hpp"
+#endif
+
+namespace cv { namespace hal {
+CV_CPU_OPTIMIZATION_NAMESPACE_BEGIN
+
+// forward declarations
+bool integral_SIMD(
+        int depth, int sdepth, int sqdepth,
+        const uchar* src, size_t srcstep,
+        uchar* sum, size_t sumstep,
+        uchar* sqsum, size_t sqsumstep,
+        uchar* tilted, size_t tstep,
+        int width, int height, int cn);
+
+#ifndef CV_CPU_OPTIMIZATION_DECLARATIONS_ONLY
+namespace {
+
+template <typename T, typename ST, typename QT>
+struct Integral_SIMD
+{
+    bool operator()(const T *, size_t,
+                    ST *, size_t,
+                    QT *, size_t,
+                    ST *, size_t,
+                    int, int, int) const
+    {
+        return false;
+    }
+};
+
+#if CV_AVX512_SKX
+template <>
+struct Integral_SIMD<uchar, double, double> {
+    Integral_SIMD() {};
+
+
+    bool operator()(const uchar *src, size_t _srcstep,
+                    double *sum,      size_t _sumstep,
+                    double *sqsum,    size_t _sqsumstep,
+                    double *tilted,   size_t _tiltedstep,
+                    int width, int height, int cn) const
+    {
+        CV_UNUSED(_tiltedstep);
+        // TODO:  Add support for 1 channel input (WIP)
+        if (!tilted && (cn <= 4))
+        {
+            calculate_integral_avx512(src, _srcstep, sum, _sumstep,
+                                      sqsum, _sqsumstep, width, height, cn);
+            return true;
+        }
+        return false;
+    }
+
+};
+#endif
+
+#if CV_SIMD && CV_SIMD_WIDTH <= 64
+
+template <>
+struct Integral_SIMD<uchar, int, double>
+{
+    Integral_SIMD() {}
+
+    bool operator()(const uchar * src, size_t _srcstep,
+                    int * sum, size_t _sumstep,
+                    double * sqsum, size_t,
+                    int * tilted, size_t,
+                    int width, int height, int cn) const
+    {
+        if (sqsum || tilted || cn != 1)
+            return false;
+
+        // the first iteration
+        memset(sum, 0, (width + 1) * sizeof(int));
+
+        // the others
+        for (int i = 0; i < height; ++i)
+        {
+            const uchar * src_row = src + _srcstep * i;
+            int * prev_sum_row = (int *)((uchar *)sum + _sumstep * i) + 1;
+            int * sum_row = (int *)((uchar *)sum + _sumstep * (i + 1)) + 1;
+
+            sum_row[-1] = 0;
+
+            v_int32 prev = vx_setzero_s32();
+            int j = 0;
+            for ( ; j + v_uint16::nlanes <= width; j += v_uint16::nlanes)
+            {
+                v_int16 el8 = v_reinterpret_as_s16(vx_load_expand(src_row + j));
+                v_int32 el4l, el4h;
+#if CV_AVX2 && CV_SIMD_WIDTH == 32
+                __m256i vsum = _mm256_add_epi16(el8.val, _mm256_slli_si256(el8.val, 2));
+                vsum = _mm256_add_epi16(vsum, _mm256_slli_si256(vsum, 4));
+                vsum = _mm256_add_epi16(vsum, _mm256_slli_si256(vsum, 8));
+                __m256i shmask = _mm256_set1_epi32(7);
+                el4l.val = _mm256_add_epi32(_mm256_cvtepi16_epi32(_v256_extract_low(vsum)), prev.val);
+                el4h.val = _mm256_add_epi32(_mm256_cvtepi16_epi32(_v256_extract_high(vsum)), _mm256_permutevar8x32_epi32(el4l.val, shmask));
+                prev.val = _mm256_permutevar8x32_epi32(el4h.val, shmask);
+#else
+                el8 += v_rotate_left<1>(el8);
+                el8 += v_rotate_left<2>(el8);
+#if CV_SIMD_WIDTH >= 32
+                el8 += v_rotate_left<4>(el8);
+#if CV_SIMD_WIDTH == 64
+                el8 += v_rotate_left<8>(el8);
+#endif
+#endif
+                v_expand(el8, el4l, el4h);
+                el4l += prev;
+                el4h += el4l;
+
+                prev = v_broadcast_element<v_int32::nlanes - 1>(el4h);
+#endif
+                v_store(sum_row + j                  , el4l + vx_load(prev_sum_row + j                  ));
+                v_store(sum_row + j + v_int32::nlanes, el4h + vx_load(prev_sum_row + j + v_int32::nlanes));
+            }
+
+            for (int v = sum_row[j - 1] - prev_sum_row[j - 1]; j < width; ++j)
+                sum_row[j] = (v += src_row[j]) + prev_sum_row[j];
+        }
+        return true;
+    }
+};
+
+template <>
+struct Integral_SIMD<uchar, float, double>
+{
+    Integral_SIMD() {}
+
+    bool operator()(const uchar * src, size_t _srcstep,
+        float * sum, size_t _sumstep,
+        double * sqsum, size_t,
+        float * tilted, size_t,
+        int width, int height, int cn) const
+    {
+        if (sqsum || tilted || cn != 1)
+            return false;
+
+        // the first iteration
+        memset(sum, 0, (width + 1) * sizeof(int));
+
+        // the others
+        for (int i = 0; i < height; ++i)
+        {
+            const uchar * src_row = src + _srcstep * i;
+            float * prev_sum_row = (float *)((uchar *)sum + _sumstep * i) + 1;
+            float * sum_row = (float *)((uchar *)sum + _sumstep * (i + 1)) + 1;
+
+            sum_row[-1] = 0;
+
+            v_float32 prev = vx_setzero_f32();
+            int j = 0;
+            for (; j + v_uint16::nlanes <= width; j += v_uint16::nlanes)
+            {
+                v_int16 el8 = v_reinterpret_as_s16(vx_load_expand(src_row + j));
+                v_float32 el4l, el4h;
+#if CV_AVX2 && CV_SIMD_WIDTH == 32
+                __m256i vsum = _mm256_add_epi16(el8.val, _mm256_slli_si256(el8.val, 2));
+                vsum = _mm256_add_epi16(vsum, _mm256_slli_si256(vsum, 4));
+                vsum = _mm256_add_epi16(vsum, _mm256_slli_si256(vsum, 8));
+                __m256i shmask = _mm256_set1_epi32(7);
+                el4l.val = _mm256_add_ps(_mm256_cvtepi32_ps(_mm256_cvtepi16_epi32(_v256_extract_low(vsum))), prev.val);
+                el4h.val = _mm256_add_ps(_mm256_cvtepi32_ps(_mm256_cvtepi16_epi32(_v256_extract_high(vsum))), _mm256_permutevar8x32_ps(el4l.val, shmask));
+                prev.val = _mm256_permutevar8x32_ps(el4h.val, shmask);
+#else
+                el8 += v_rotate_left<1>(el8);
+                el8 += v_rotate_left<2>(el8);
+#if CV_SIMD_WIDTH >= 32
+                el8 += v_rotate_left<4>(el8);
+#if CV_SIMD_WIDTH == 64
+                el8 += v_rotate_left<8>(el8);
+#endif
+#endif
+                v_int32 el4li, el4hi;
+                v_expand(el8, el4li, el4hi);
+                el4l = v_cvt_f32(el4li) + prev;
+                el4h = v_cvt_f32(el4hi) + el4l;
+
+                prev = v_broadcast_element<v_float32::nlanes - 1>(el4h);
+#endif
+                v_store(sum_row + j                    , el4l + vx_load(prev_sum_row + j                    ));
+                v_store(sum_row + j + v_float32::nlanes, el4h + vx_load(prev_sum_row + j + v_float32::nlanes));
+            }
+
+            for (float v = sum_row[j - 1] - prev_sum_row[j - 1]; j < width; ++j)
+                sum_row[j] = (v += src_row[j]) + prev_sum_row[j];
+        }
+        return true;
+    }
+};
+
+#endif
+
+} // namespace anon
+
+bool integral_SIMD(
+        int depth, int sdepth, int sqdepth,
+        const uchar* src, size_t srcstep,
+        uchar* sum, size_t sumstep,
+        uchar* sqsum, size_t sqsumstep,
+        uchar* tilted, size_t tstep,
+        int width, int height, int cn)
+{
+    CV_INSTRUMENT_REGION();
+
+#define ONE_CALL(T, ST, QT) \
+    return Integral_SIMD<T, ST, QT>()((const T*)src, srcstep, (ST*)sum, sumstep, (QT*)sqsum, sqsumstep, (ST*)tilted, tstep, width, height, cn)
+
+    if( depth == CV_8U && sdepth == CV_32S && sqdepth == CV_64F )
+        ONE_CALL(uchar, int, double);
+    else if( depth == CV_8U && sdepth == CV_32S && sqdepth == CV_32F )
+        ONE_CALL(uchar, int, float);
+    else if( depth == CV_8U && sdepth == CV_32S && sqdepth == CV_32S )
+        ONE_CALL(uchar, int, int);
+    else if( depth == CV_8U && sdepth == CV_32F && sqdepth == CV_64F )
+        ONE_CALL(uchar, float, double);
+    else if( depth == CV_8U && sdepth == CV_32F && sqdepth == CV_32F )
+        ONE_CALL(uchar, float, float);
+    else if( depth == CV_8U && sdepth == CV_64F && sqdepth == CV_64F )
+        ONE_CALL(uchar, double, double);
+    else if( depth == CV_16U && sdepth == CV_64F && sqdepth == CV_64F )
+        ONE_CALL(ushort, double, double);
+    else if( depth == CV_16S && sdepth == CV_64F && sqdepth == CV_64F )
+        ONE_CALL(short, double, double);
+    else if( depth == CV_32F && sdepth == CV_32F && sqdepth == CV_64F )
+        ONE_CALL(float, float, double);
+    else if( depth == CV_32F && sdepth == CV_32F && sqdepth == CV_32F )
+        ONE_CALL(float, float, float);
+    else if( depth == CV_32F && sdepth == CV_64F && sqdepth == CV_64F )
+        ONE_CALL(float, double, double);
+    else if( depth == CV_64F && sdepth == CV_64F && sqdepth == CV_64F )
+        ONE_CALL(double, double, double);
+    else
+        return false;
+
+#undef ONE_CALL
+}
+
+#endif
+CV_CPU_OPTIMIZATION_NAMESPACE_END
+}} // cv::hal::
diff --git a/modules/java/generator/gen_java.py b/modules/java/generator/gen_java.py
index dc47e6f62e..543b8b530a 100755
--- a/modules/java/generator/gen_java.py
+++ b/modules/java/generator/gen_java.py
@@ -80,6 +80,15 @@ type_dict = {
         'suffix': 'Ljava_lang_String_2',
         'j_import': 'java.lang.String'
     },
+    'vector_string': {  # std::vector<std::string>, see "vector_String" in modules/core/misc/java/gen_dict.json
+        'j_type': 'List<String>',
+        'jn_type': 'List<String>',
+        'jni_type': 'jobject',
+        'jni_var': 'std::vector< std::string > %(n)s',
+        'suffix': 'Ljava_util_List',
+        'v_type': 'string',
+        'j_import': 'java.lang.String'
+    },
 }
 
 # Defines a rule to add extra prefixes for names from specific namespaces.
@@ -925,7 +934,10 @@ class JavaWrapperGenerator(object):
                     c_epilogue.append("Mat* _retval_ = new Mat();")
                     c_epilogue.append(fi.ctype+"_to_Mat(_ret_val_vector_, *_retval_);")
                 else:
-                    c_epilogue.append("return " + fi.ctype + "_to_List(env, _ret_val_vector_);")
+                    if ret:
+                        c_epilogue.append("jobject _retval_ = " + fi.ctype + "_to_List(env, _ret_val_vector_);")
+                    else:
+                        c_epilogue.append("return " + fi.ctype + "_to_List(env, _ret_val_vector_);")
             if fi.classname:
                 if not fi.ctype: # c-tor
                     retval = fi.fullClass(isCPP=True) + "* _retval_ = "
diff --git a/modules/java/generator/src/cpp/listconverters.cpp b/modules/java/generator/src/cpp/listconverters.cpp
index d1f45c65e6..94702acc56 100644
--- a/modules/java/generator/src/cpp/listconverters.cpp
+++ b/modules/java/generator/src/cpp/listconverters.cpp
@@ -57,3 +57,54 @@ void Copy_vector_String_to_List(JNIEnv* env, std::vector<cv::String>& vs, jobjec
         env->DeleteLocalRef(element);
     }
 }
+
+
+jobject vector_string_to_List(JNIEnv* env, std::vector<std::string>& vs) {
+
+    static jclass juArrayList   = ARRAYLIST(env);
+    static jmethodID m_create   = CONSTRUCTOR(env, juArrayList);
+    jmethodID m_add       = LIST_ADD(env, juArrayList);
+
+    jobject result = env->NewObject(juArrayList, m_create, vs.size());
+    for (std::vector<std::string>::iterator it = vs.begin(); it != vs.end(); ++it) {
+        jstring element = env->NewStringUTF((*it).c_str());
+        env->CallBooleanMethod(result, m_add, element);
+        env->DeleteLocalRef(element);
+    }
+    return result;
+}
+
+std::vector<std::string> List_to_vector_string(JNIEnv* env, jobject list)
+{
+    static jclass juArrayList       = ARRAYLIST(env);
+    jmethodID m_size       = LIST_SIZE(env,juArrayList);
+    jmethodID m_get        = LIST_GET(env, juArrayList);
+
+    jint len = env->CallIntMethod(list, m_size);
+    std::vector<std::string> result;
+    result.reserve(len);
+    for (jint i=0; i<len; i++)
+    {
+        jstring element = static_cast<jstring>(env->CallObjectMethod(list, m_get, i));
+        const char* pchars = env->GetStringUTFChars(element, NULL);
+        result.push_back(pchars);
+        env->ReleaseStringUTFChars(element, pchars);
+        env->DeleteLocalRef(element);
+    }
+    return result;
+}
+
+void Copy_vector_string_to_List(JNIEnv* env, std::vector<std::string>& vs, jobject list)
+{
+    static jclass juArrayList       = ARRAYLIST(env);
+    jmethodID m_clear     = LIST_CLEAR(env, juArrayList);
+    jmethodID m_add       = LIST_ADD(env, juArrayList);
+
+    env->CallVoidMethod(list, m_clear);
+    for (std::vector<std::string>::iterator it = vs.begin(); it != vs.end(); ++it)
+    {
+        jstring element = env->NewStringUTF((*it).c_str());
+        env->CallBooleanMethod(list, m_add, element);
+        env->DeleteLocalRef(element);
+    }
+}
diff --git a/modules/java/generator/src/cpp/listconverters.hpp b/modules/java/generator/src/cpp/listconverters.hpp
index 4d63d9d86f..0ffd93489a 100644
--- a/modules/java/generator/src/cpp/listconverters.hpp
+++ b/modules/java/generator/src/cpp/listconverters.hpp
@@ -16,4 +16,11 @@ std::vector<cv::String> List_to_vector_String(JNIEnv* env, jobject list);
 
 void Copy_vector_String_to_List(JNIEnv* env, std::vector<cv::String>& vs, jobject list);
 
+
+jobject vector_string_to_List(JNIEnv* env, std::vector<std::string>& vs);
+
+std::vector<std::string> List_to_vector_string(JNIEnv* env, jobject list);
+
+void Copy_vector_string_to_List(JNIEnv* env, std::vector<std::string>& vs, jobject list);
+
 #endif	/* LISTCONVERTERS_HPP */
diff --git a/modules/objdetect/include/opencv2/objdetect.hpp b/modules/objdetect/include/opencv2/objdetect.hpp
index 1cbbf8456f..097c5923af 100644
--- a/modules/objdetect/include/opencv2/objdetect.hpp
+++ b/modules/objdetect/include/opencv2/objdetect.hpp
@@ -691,8 +691,8 @@ public:
     CV_WRAP bool detect(InputArray img, OutputArray points) const;
 
     /** @brief Decodes QR code in image once it's found by the detect() method.
-     Returns UTF8-encoded output string or empty string if the code cannot be decoded.
 
+     Returns UTF8-encoded output string or empty string if the code cannot be decoded.
      @param img grayscale or color (BGR) image containing QR code.
      @param points Quadrangle vertices found by detect() method (or some other algorithm).
      @param straight_qrcode The optional output image containing rectified and binarized QR code
@@ -702,11 +702,44 @@ public:
     /** @brief Both detects and decodes QR code
 
      @param img grayscale or color (BGR) image containing QR code.
-     @param points opiotnal output array of vertices of the found QR code quadrangle. Will be empty if not found.
+     @param points optional output array of vertices of the found QR code quadrangle. Will be empty if not found.
      @param straight_qrcode The optional output image containing rectified and binarized QR code
      */
     CV_WRAP std::string detectAndDecode(InputArray img, OutputArray points=noArray(),
                                         OutputArray straight_qrcode = noArray());
+    /** @brief Detects QR codes in image and returns the vector of the quadrangles containing the codes.
+     @param img grayscale or color (BGR) image containing (or not) QR codes.
+     @param points Output vector of vector of vertices of the minimum-area quadrangle containing the codes.
+     */
+    CV_WRAP
+    bool detectMulti(InputArray img, OutputArray points) const;
+
+    /** @brief Decodes QR codes in image once it's found by the detect() method.
+     @param img grayscale or color (BGR) image containing QR codes.
+     @param decoded_info UTF8-encoded output vector of string or empty vector of string if the codes cannot be decoded.
+     @param points vector of Quadrangle vertices found by detect() method (or some other algorithm).
+     @param straight_qrcode The optional output vector of images containing rectified and binarized QR codes
+     */
+    CV_WRAP
+    bool decodeMulti(
+            InputArray img, InputArray points,
+            CV_OUT std::vector<std::string>& decoded_info,
+            OutputArrayOfArrays straight_qrcode = noArray()
+    ) const;
+
+    /** @brief Both detects and decodes QR codes
+    @param img grayscale or color (BGR) image containing QR codes.
+    @param decoded_info UTF8-encoded output vector of string or empty vector of string if the codes cannot be decoded.
+    @param points optional output vector of vertices of the found QR code quadrangles. Will be empty if not found.
+    @param straight_qrcode The optional output vector of images containing rectified and binarized QR codes
+    */
+    CV_WRAP
+    bool detectAndDecodeMulti(
+            InputArray img, CV_OUT std::vector<std::string>& decoded_info,
+            OutputArray points = noArray(),
+            OutputArrayOfArrays straight_qrcode = noArray()
+    ) const;
+
 protected:
     struct Impl;
     Ptr<Impl> p;
diff --git a/modules/objdetect/misc/java/test/QRCodeDetectorTest.java b/modules/objdetect/misc/java/test/QRCodeDetectorTest.java
index 9879772e42..cd8be409aa 100644
--- a/modules/objdetect/misc/java/test/QRCodeDetectorTest.java
+++ b/modules/objdetect/misc/java/test/QRCodeDetectorTest.java
@@ -1,9 +1,11 @@
 package org.opencv.test.objdetect;
 
+import java.util.List;
 import org.opencv.core.Mat;
 import org.opencv.objdetect.QRCodeDetector;
 import org.opencv.imgcodecs.Imgcodecs;
 import org.opencv.test.OpenCVTestCase;
+import java.util.ArrayList;
 
 public class QRCodeDetectorTest extends OpenCVTestCase {
 
@@ -21,9 +23,27 @@ public class QRCodeDetectorTest extends OpenCVTestCase {
 
     public void testDetectAndDecode() {
         Mat img = Imgcodecs.imread(testDataPath + "/cv/qrcode/link_ocv.jpg");
+        assertFalse(img.empty());
         QRCodeDetector detector = new QRCodeDetector();
+        assertNotNull(detector);
         String output = detector.detectAndDecode(img);
         assertEquals(output, "https://opencv.org/");
     }
 
+    public void testDetectAndDecodeMulti() {
+        Mat img = Imgcodecs.imread(testDataPath + "/cv/qrcode/multiple/6_qrcodes.png");
+        assertFalse(img.empty());
+        QRCodeDetector detector = new QRCodeDetector();
+        assertNotNull(detector);
+        List < String > output = new ArrayList< String >();
+        boolean result = detector.detectAndDecodeMulti(img, output);
+        assertTrue(result);
+        assertEquals(output.size(), 6);
+        assertEquals(output.get(0), "SKIP");
+        assertEquals(output.get(1), "EXTRA");
+        assertEquals(output.get(2), "TWO STEPS FORWARD");
+        assertEquals(output.get(3), "STEP BACK");
+        assertEquals(output.get(4), "QUESTION");
+        assertEquals(output.get(5), "STEP FORWARD");
+    }
 }
diff --git a/modules/objdetect/misc/python/test/test_qrcode_detect.py b/modules/objdetect/misc/python/test/test_qrcode_detect.py
index 18f7ed79ed..8a95c8bce5 100644
--- a/modules/objdetect/misc/python/test/test_qrcode_detect.py
+++ b/modules/objdetect/misc/python/test/test_qrcode_detect.py
@@ -11,8 +11,42 @@ import cv2 as cv
 from tests_common import NewOpenCVTests
 
 class qrcode_detector_test(NewOpenCVTests):
+
+    def test_detect(self):
+        img = cv.imread(os.path.join(self.extraTestDataPath, 'cv/qrcode/link_ocv.jpg'))
+        self.assertFalse(img is None)
+        detector = cv.QRCodeDetector()
+        retval, points = detector.detect(img)
+        self.assertTrue(retval)
+        self.assertEqual(points.shape, (1, 4, 2))
+
     def test_detect_and_decode(self):
         img = cv.imread(os.path.join(self.extraTestDataPath, 'cv/qrcode/link_ocv.jpg'))
+        self.assertFalse(img is None)
         detector = cv.QRCodeDetector()
         retval, points, straight_qrcode = detector.detectAndDecode(img)
-        self.assertEqual(retval, "https://opencv.org/");
+        self.assertEqual(retval, "https://opencv.org/")
+        self.assertEqual(points.shape, (1, 4, 2))
+
+    def test_detect_multi(self):
+        img = cv.imread(os.path.join(self.extraTestDataPath, 'cv/qrcode/multiple/6_qrcodes.png'))
+        self.assertFalse(img is None)
+        detector = cv.QRCodeDetector()
+        retval, points = detector.detectMulti(img)
+        self.assertTrue(retval)
+        self.assertEqual(points.shape, (6, 4, 2))
+
+    def test_detect_and_decode_multi(self):
+        img = cv.imread(os.path.join(self.extraTestDataPath, 'cv/qrcode/multiple/6_qrcodes.png'))
+        self.assertFalse(img is None)
+        detector = cv.QRCodeDetector()
+        retval, decoded_data, points, straight_qrcode = detector.detectAndDecodeMulti(img)
+        self.assertTrue(retval)
+        self.assertEqual(len(decoded_data), 6)
+        self.assertEqual(decoded_data[0], "TWO STEPS FORWARD")
+        self.assertEqual(decoded_data[1], "EXTRA")
+        self.assertEqual(decoded_data[2], "SKIP")
+        self.assertEqual(decoded_data[3], "STEP FORWARD")
+        self.assertEqual(decoded_data[4], "STEP BACK")
+        self.assertEqual(decoded_data[5], "QUESTION")
+        self.assertEqual(points.shape, (6, 4, 2))
diff --git a/modules/objdetect/perf/perf_qrcode_pipeline.cpp b/modules/objdetect/perf/perf_qrcode_pipeline.cpp
index da5f278c66..44ab54f4b2 100644
--- a/modules/objdetect/perf/perf_qrcode_pipeline.cpp
+++ b/modules/objdetect/perf/perf_qrcode_pipeline.cpp
@@ -53,6 +53,56 @@ PERF_TEST_P_(Perf_Objdetect_QRCode, decode)
 }
 #endif
 
+typedef ::perf::TestBaseWithParam< std::string > Perf_Objdetect_QRCode_Multi;
+
+PERF_TEST_P_(Perf_Objdetect_QRCode_Multi, detectMulti)
+{
+    const std::string name_current_image = GetParam();
+    const std::string root = "cv/qrcode/multiple/";
+
+    std::string image_path = findDataFile(root + name_current_image);
+    Mat src = imread(image_path);
+    ASSERT_FALSE(src.empty()) << "Can't read image: " << image_path;
+    std::vector<Point2f> corners;
+    QRCodeDetector qrcode;
+    TEST_CYCLE() ASSERT_TRUE(qrcode.detectMulti(src, corners));
+    SANITY_CHECK(corners);
+}
+
+#ifdef HAVE_QUIRC
+PERF_TEST_P_(Perf_Objdetect_QRCode_Multi, decodeMulti)
+{
+    const std::string name_current_image = GetParam();
+    const std::string root = "cv/qrcode/multiple/";
+
+    std::string image_path = findDataFile(root + name_current_image);
+    Mat src = imread(image_path);
+    ASSERT_FALSE(src.empty()) << "Can't read image: " << image_path;
+    QRCodeDetector qrcode;
+    std::vector<Point2f> corners;
+    ASSERT_TRUE(qrcode.detectMulti(src, corners));
+    std::vector<Mat> straight_barcode;
+    std::vector< cv::String > decoded_info;
+    TEST_CYCLE()
+    {
+        ASSERT_TRUE(qrcode.decodeMulti(src, corners, decoded_info, straight_barcode));
+        for(size_t i = 0; i < decoded_info.size(); i++)
+        {
+            ASSERT_FALSE(decoded_info[i].empty());
+        }
+    }
+    std::vector < std::vector< uint8_t > > decoded_info_uint8_t;
+    for(size_t i = 0; i < decoded_info.size(); i++)
+    {
+        std::vector< uint8_t > tmp(decoded_info[i].begin(), decoded_info[i].end());
+        decoded_info_uint8_t.push_back(tmp);
+    }
+    SANITY_CHECK(decoded_info_uint8_t);
+    SANITY_CHECK(straight_barcode);
+
+}
+#endif
+
 INSTANTIATE_TEST_CASE_P(/*nothing*/, Perf_Objdetect_QRCode,
     ::testing::Values(
         "version_1_down.jpg", "version_1_left.jpg", "version_1_right.jpg", "version_1_up.jpg", "version_1_top.jpg",
@@ -61,6 +111,13 @@ INSTANTIATE_TEST_CASE_P(/*nothing*/, Perf_Objdetect_QRCode,
     )
 );
 
+INSTANTIATE_TEST_CASE_P(/*nothing*/, Perf_Objdetect_QRCode_Multi,
+    ::testing::Values(
+      "2_qrcodes.png", "3_close_qrcodes.png", "3_qrcodes.png", "4_qrcodes.png",
+       "5_qrcodes.png", "6_qrcodes.png", "7_qrcodes.png", "8_close_qrcodes.png"
+    )
+);
+
 typedef ::perf::TestBaseWithParam< tuple< std::string, Size > > Perf_Objdetect_Not_QRCode;
 
 PERF_TEST_P_(Perf_Objdetect_Not_QRCode, detect)
diff --git a/modules/objdetect/src/qrcode.cpp b/modules/objdetect/src/qrcode.cpp
index 925f28886f..a80fa16627 100644
--- a/modules/objdetect/src/qrcode.cpp
+++ b/modules/objdetect/src/qrcode.cpp
@@ -22,6 +22,48 @@ namespace cv
 {
 using std::vector;
 
+static bool checkQRInputImage(InputArray img, Mat& gray)
+{
+    CV_Assert(!img.empty());
+    CV_CheckDepthEQ(img.depth(), CV_8U, "");
+
+    if (img.cols() <= 20 || img.rows() <= 20)
+    {
+        return false;  // image data is not enough for providing reliable results
+    }
+    int incn = img.channels();
+    CV_Check(incn, incn == 1 || incn == 3 || incn == 3, "");
+    if (incn == 3 || incn == 4)
+    {
+        cvtColor(img, gray, COLOR_BGR2GRAY);
+    }
+    else
+    {
+        gray = img.getMat();
+    }
+    return true;
+}
+
+static void updatePointsResult(OutputArray points_, const vector<Point2f>& points)
+{
+    if (points_.needed())
+    {
+        int N = int(points.size() / 4);
+        if (N > 0)
+        {
+            Mat m_p(N, 4, CV_32FC2, (void*)&points[0]);
+            int points_type = points_.fixedType() ? points_.type() : CV_32FC2;
+            m_p.reshape(2, points_.rows()).convertTo(points_, points_type);  // Mat layout: N x 4 x 2cn
+        }
+        else
+        {
+            points_.release();
+        }
+    }
+}
+
+
+
 class QRDetect
 {
 public:
@@ -35,6 +77,7 @@ public:
 protected:
     vector<Vec3d> searchHorizontalLines();
     vector<Point2f> separateVerticalLines(const vector<Vec3d> &list_lines);
+    vector<Point2f> extractVerticalLines(const vector<Vec3d> &list_lines, double eps);
     void fixationPoints(vector<Point2f> &local_point);
     vector<Point2f> getQuadrilateral(vector<Point2f> angle_list);
     bool testBypassRoute(vector<Point2f> hull, int start, int finish);
@@ -112,7 +155,7 @@ vector<Vec3d> QRDetect::searchHorizontalLines()
         {
             if (bin_barcode_row[x] == future_pixel)
             {
-                future_pixel = 255 - future_pixel;
+                future_pixel = static_cast<uint8_t>(~future_pixel);
                 pixels_position.push_back(x);
             }
         }
@@ -125,7 +168,7 @@ vector<Vec3d> QRDetect::searchHorizontalLines()
             test_lines[3] = static_cast<double>(pixels_position[i + 2] - pixels_position[i + 1]);
             test_lines[4] = static_cast<double>(pixels_position[i + 3] - pixels_position[i + 2]);
 
-            double length = 0.0, weight = 0.0;
+            double length = 0.0, weight = 0.0;  // TODO avoid 'double' calculations
 
             for (size_t j = 0; j < test_lines_size; j++) { length += test_lines[j]; }
 
@@ -152,96 +195,115 @@ vector<Vec3d> QRDetect::searchHorizontalLines()
 vector<Point2f> QRDetect::separateVerticalLines(const vector<Vec3d> &list_lines)
 {
     CV_TRACE_FUNCTION();
-    vector<Vec3d> result;
-    int temp_length;
-    vector<Point2f> point2f_result;
-    uint8_t next_pixel;
-    vector<double> test_lines;
-
 
     for (int coeff_epsilon = 1; coeff_epsilon < 10; coeff_epsilon++)
     {
-        result.clear();
-        temp_length = 0;
-        point2f_result.clear();
-
-        for (size_t pnt = 0; pnt < list_lines.size(); pnt++)
+        vector<Point2f> point2f_result = extractVerticalLines(list_lines, eps_horizontal * coeff_epsilon);
+        if (!point2f_result.empty())
         {
-            const int x = cvRound(list_lines[pnt][0] + list_lines[pnt][2] * 0.5);
-            const int y = cvRound(list_lines[pnt][1]);
+            vector<Point2f> centers;
+            Mat labels;
+            double compactness = kmeans(
+                    point2f_result, 3, labels,
+                    TermCriteria(TermCriteria::EPS + TermCriteria::COUNT, 10, 0.1),
+                    3, KMEANS_PP_CENTERS, centers);
+            if (compactness == 0)
+                continue;
+            if (compactness > 0)
+            {
+                return point2f_result;
+            }
+        }
+    }
+    return vector<Point2f>();  // nothing
+}
+
+vector<Point2f> QRDetect::extractVerticalLines(const vector<Vec3d> &list_lines, double eps)
+{
+    CV_TRACE_FUNCTION();
+    vector<Vec3d> result;
+    vector<double> test_lines; test_lines.reserve(6);
+
+    for (size_t pnt = 0; pnt < list_lines.size(); pnt++)
+    {
+        const int x = cvRound(list_lines[pnt][0] + list_lines[pnt][2] * 0.5);
+        const int y = cvRound(list_lines[pnt][1]);
 
-            // --------------- Search vertical up-lines --------------- //
+        // --------------- Search vertical up-lines --------------- //
 
-            test_lines.clear();
-            uint8_t future_pixel_up = 255;
+        test_lines.clear();
+        uint8_t future_pixel_up = 255;
 
-            for (int j = y; j < bin_barcode.rows - 1; j++)
+        int temp_length_up = 0;
+        for (int j = y; j < bin_barcode.rows - 1; j++)
+        {
+            uint8_t next_pixel = bin_barcode.ptr<uint8_t>(j + 1)[x];
+            temp_length_up++;
+            if (next_pixel == future_pixel_up)
             {
-                next_pixel = bin_barcode.ptr<uint8_t>(j + 1)[x];
-                temp_length++;
-                if (next_pixel == future_pixel_up)
-                {
-                    future_pixel_up = 255 - future_pixel_up;
-                    test_lines.push_back(temp_length);
-                    temp_length = 0;
-                    if (test_lines.size() == 3) { break; }
-                }
+                future_pixel_up = static_cast<uint8_t>(~future_pixel_up);
+                test_lines.push_back(temp_length_up);
+                temp_length_up = 0;
+                if (test_lines.size() == 3)
+                    break;
             }
+        }
 
-            // --------------- Search vertical down-lines --------------- //
+        // --------------- Search vertical down-lines --------------- //
 
-            uint8_t future_pixel_down = 255;
-            for (int j = y; j >= 1; j--)
+        int temp_length_down = 0;
+        uint8_t future_pixel_down = 255;
+        for (int j = y; j >= 1; j--)
+        {
+            uint8_t next_pixel = bin_barcode.ptr<uint8_t>(j - 1)[x];
+            temp_length_down++;
+            if (next_pixel == future_pixel_down)
             {
-                next_pixel = bin_barcode.ptr<uint8_t>(j - 1)[x];
-                temp_length++;
-                if (next_pixel == future_pixel_down)
-                {
-                    future_pixel_down = 255 - future_pixel_down;
-                    test_lines.push_back(temp_length);
-                    temp_length = 0;
-                    if (test_lines.size() == 6) { break; }
-                }
+                future_pixel_down = static_cast<uint8_t>(~future_pixel_down);
+                test_lines.push_back(temp_length_down);
+                temp_length_down = 0;
+                if (test_lines.size() == 6)
+                    break;
             }
+        }
 
-            // --------------- Compute vertical lines --------------- //
+        // --------------- Compute vertical lines --------------- //
 
-            if (test_lines.size() == 6)
-            {
-                double length = 0.0, weight = 0.0;
+        if (test_lines.size() == 6)
+        {
+            double length = 0.0, weight = 0.0;  // TODO avoid 'double' calculations
 
-                for (size_t i = 0; i < test_lines.size(); i++) { length += test_lines[i]; }
+            for (size_t i = 0; i < test_lines.size(); i++)
+                length += test_lines[i];
 
-                CV_Assert(length > 0);
-                for (size_t i = 0; i < test_lines.size(); i++)
+            CV_Assert(length > 0);
+            for (size_t i = 0; i < test_lines.size(); i++)
+            {
+                if (i % 3 != 0)
                 {
-                    if (i % 3 != 0) { weight += fabs((test_lines[i] / length) - 1.0/ 7.0); }
-                    else            { weight += fabs((test_lines[i] / length) - 3.0/14.0); }
+                    weight += fabs((test_lines[i] / length) - 1.0/ 7.0);
                 }
-
-                if(weight < eps_horizontal * coeff_epsilon)
+                else
                 {
-                    result.push_back(list_lines[pnt]);
+                    weight += fabs((test_lines[i] / length) - 3.0/14.0);
                 }
             }
-        }
-        if (result.size() > 2)
-        {
-            for (size_t i = 0; i < result.size(); i++)
+
+            if (weight < eps)
             {
-                point2f_result.push_back(
-                      Point2f(static_cast<float>(result[i][0] + result[i][2] * 0.5),
-                              static_cast<float>(result[i][1])));
+                result.push_back(list_lines[pnt]);
             }
+        }
+    }
 
-            vector<Point2f> centers;
-            Mat labels;
-            double compactness;
-            compactness = kmeans(point2f_result, 3, labels,
-                 TermCriteria( TermCriteria::EPS + TermCriteria::COUNT, 10, 0.1),
-                 3, KMEANS_PP_CENTERS, centers);
-            if (compactness == 0) { continue; }
-            if (compactness > 0)  { break; }
+    vector<Point2f> point2f_result;
+    if (result.size() > 2)
+    {
+        for (size_t i = 0; i < result.size(); i++)
+        {
+            point2f_result.push_back(
+                  Point2f(static_cast<float>(result[i][0] + result[i][2] * 0.5),
+                          static_cast<float>(result[i][1])));
         }
     }
     return point2f_result;
@@ -302,19 +364,25 @@ void QRDetect::fixationPoints(vector<Point2f> &local_point)
 
         for (size_t k = 0; k < list_line_iter.size(); k++)
         {
+            LineIterator& li = list_line_iter[k];
             uint8_t future_pixel = 255, count_index = 0;
-            for(int j = 0; j < list_line_iter[k].count; j++, ++list_line_iter[k])
+            for(int j = 0; j < li.count; j++, ++li)
             {
-                if (list_line_iter[k].pos().x >= bin_barcode.cols ||
-                    list_line_iter[k].pos().y >= bin_barcode.rows) { break; }
-                const uint8_t value = bin_barcode.at<uint8_t>(list_line_iter[k].pos());
+                const Point p = li.pos();
+                if (p.x >= bin_barcode.cols ||
+                    p.y >= bin_barcode.rows)
+                {
+                    break;
+                }
+
+                const uint8_t value = bin_barcode.at<uint8_t>(p);
                 if (value == future_pixel)
                 {
-                    future_pixel = 255 - future_pixel;
+                    future_pixel = static_cast<uint8_t>(~future_pixel);
                     count_index++;
                     if (count_index == 3)
                     {
-                        list_area_pnt.push_back(list_line_iter[k].pos());
+                        list_area_pnt.push_back(p);
                         break;
                     }
                 }
@@ -454,7 +522,7 @@ bool QRDetect::computeTransformationPoints()
             next_pixel = bin_barcode.ptr<uint8_t>(cvRound(localization_points[i].y))[index + 1];
             if (next_pixel == future_pixel)
             {
-                future_pixel = 255 - future_pixel;
+                future_pixel = static_cast<uint8_t>(~future_pixel);
                 count_test_lines++;
                 if (count_test_lines == 2)
                 {
@@ -623,11 +691,12 @@ vector<Point2f> QRDetect::getQuadrilateral(vector<Point2f> angle_list)
                                             angle_list[(i + 1) % angle_size]);
         for(int j = 0; j < line_iter.count; j++, ++line_iter)
         {
-            value = bin_barcode.at<uint8_t>(line_iter.pos());
-            mask_value = mask.at<uint8_t>(line_iter.pos() + Point(1, 1));
+            Point p = line_iter.pos();
+            value = bin_barcode.at<uint8_t>(p);
+            mask_value = mask.at<uint8_t>(p + Point(1, 1));
             if (value == 0 && mask_value == 0)
             {
-                floodFill(fill_bin_barcode, mask, line_iter.pos(), 255,
+                floodFill(fill_bin_barcode, mask, p, 255,
                           0, Scalar(), Scalar(), FLOODFILL_MASK_ONLY);
             }
         }
@@ -868,26 +937,16 @@ void QRCodeDetector::setEpsY(double epsY) { p->epsY = epsY; }
 
 bool QRCodeDetector::detect(InputArray in, OutputArray points) const
 {
-    Mat inarr = in.getMat();
-    CV_Assert(!inarr.empty());
-    CV_Assert(inarr.depth() == CV_8U);
-    if (inarr.cols <= 20 || inarr.rows <= 20)
-        return false;  // image data is not enough for providing reliable results
-
-    int incn = inarr.channels();
-    if( incn == 3 || incn == 4 )
-    {
-        Mat gray;
-        cvtColor(inarr, gray, COLOR_BGR2GRAY);
-        inarr = gray;
-    }
+    Mat inarr;
+    if (!checkQRInputImage(in, inarr))
+        return false;
 
     QRDetect qrdet;
     qrdet.init(inarr, p->epsX, p->epsY);
     if (!qrdet.localization()) { return false; }
     if (!qrdet.computeTransformationPoints()) { return false; }
     vector<Point2f> pnts2f = qrdet.getTransformationPoints();
-    Mat(pnts2f).convertTo(points, points.fixedType() ? points.type() : CV_32FC2);
+    updatePointsResult(points, pnts2f);
     return true;
 }
 
@@ -916,24 +975,7 @@ void QRDecode::init(const Mat &src, const vector<Point2f> &points)
 {
     CV_TRACE_FUNCTION();
     vector<Point2f> bbox = points;
-    double coeff_expansion;
-    const int min_side = std::min(src.size().width, src.size().height);
-    if (min_side > 512)
-    {
-        coeff_expansion = min_side / 512;
-        const int width  = cvRound(src.size().width  / coeff_expansion);
-        const int height = cvRound(src.size().height / coeff_expansion);
-        Size new_size(width, height);
-        resize(src, original, new_size, 0, 0, INTER_AREA);
-            for (size_t i = 0; i < bbox.size(); i++)
-            {
-                bbox[i] /= static_cast<float>(coeff_expansion);
-            }
-    }
-    else
-    {
-        original = src.clone();
-    }
+    original = src.clone();
     intermediate = Mat::zeros(original.size(), CV_8UC1);
     original_points = bbox;
     version = 0;
@@ -999,7 +1041,11 @@ bool QRDecode::versionDefinition()
     for(int j = 0; j < line_iter.count; j++, ++line_iter)
     {
         const uint8_t value = intermediate.at<uint8_t>(line_iter.pos());
-        if (value == 0) { black_point = line_iter.pos(); break; }
+        if (value == 0)
+        {
+            black_point = line_iter.pos();
+            break;
+        }
     }
 
     Mat mask = Mat::zeros(intermediate.rows + 2, intermediate.cols + 2, CV_8UC1);
@@ -1032,7 +1078,7 @@ bool QRDecode::versionDefinition()
     {
         if (intermediate_row[i] == future_pixel)
         {
-            future_pixel = 255 - future_pixel;
+            future_pixel = static_cast<uint8_t>(~future_pixel);
             transition_x++;
         }
     }
@@ -1043,11 +1089,10 @@ bool QRDecode::versionDefinition()
         const uint8_t value = intermediate.at<uint8_t>(Point(j, remote_point.x));
         if (value == future_pixel)
         {
-            future_pixel = 255 - future_pixel;
+            future_pixel = static_cast<uint8_t>(~future_pixel);
             transition_y++;
         }
     }
-
     version = saturate_cast<uint8_t>((std::min(transition_x, transition_y) - 1) * 0.25 - 1);
     if ( !(  0 < version && version <= 40 ) ) { return false; }
     version_size = 21 + (version - 1) * 4;
@@ -1161,19 +1206,9 @@ bool QRDecode::fullDecodingProcess()
 std::string QRCodeDetector::decode(InputArray in, InputArray points,
                                    OutputArray straight_qrcode)
 {
-    Mat inarr = in.getMat();
-    CV_Assert(!inarr.empty());
-    CV_Assert(inarr.depth() == CV_8U);
-    if (inarr.cols <= 20 || inarr.rows <= 20)
-        return cv::String();  // image data is not enough for providing reliable results
-
-    int incn = inarr.channels();
-    if( incn == 3 || incn == 4 )
-    {
-        Mat gray;
-        cvtColor(inarr, gray, COLOR_BGR2GRAY);
-        inarr = gray;
-    }
+    Mat inarr;
+    if (!checkQRInputImage(in, inarr))
+        return std::string();
 
     vector<Point2f> src_points;
     points.copyTo(src_points);
@@ -1200,33 +1235,1131 @@ std::string QRCodeDetector::detectAndDecode(InputArray in,
                                             OutputArray points_,
                                             OutputArray straight_qrcode)
 {
-    Mat inarr = in.getMat();
-    CV_Assert(!inarr.empty());
-    CV_Assert(inarr.depth() == CV_8U);
-    if (inarr.cols <= 20 || inarr.rows <= 20)
-        return cv::String();  // image data is not enough for providing reliable results
-
-    int incn = inarr.channels();
-    if( incn == 3 || incn == 4 )
+    Mat inarr;
+    if (!checkQRInputImage(in, inarr))
     {
-        Mat gray;
-        cvtColor(inarr, gray, COLOR_BGR2GRAY);
-        inarr = gray;
+        points_.release();
+        return std::string();
     }
 
     vector<Point2f> points;
     bool ok = detect(inarr, points);
-    if( points_.needed() )
+    if (!ok)
     {
-        if( ok )
-            Mat(points).copyTo(points_);
-        else
-            points_.release();
+        points_.release();
+        return std::string();
     }
-    std::string decoded_info;
-    if( ok )
-        decoded_info = decode(inarr, points, straight_qrcode);
+    updatePointsResult(points_, points);
+    std::string decoded_info = decode(inarr, points, straight_qrcode);
     return decoded_info;
 }
 
+
+class QRDetectMulti : public QRDetect
+{
+public:
+    void init(const Mat& src, double eps_vertical_ = 0.2, double eps_horizontal_ = 0.1);
+    bool localization();
+    bool computeTransformationPoints(const size_t cur_ind);
+    vector< vector < Point2f > > getTransformationPoints() { return transformation_points;}
+
+protected:
+    int findNumberLocalizationPoints(vector<Point2f>& tmp_localization_points);
+    void findQRCodeContours(vector<Point2f>& tmp_localization_points, vector< vector< Point2f > >& true_points_group, const int& num_qrcodes);
+    bool checkSets(vector<vector<Point2f> >& true_points_group, vector<vector<Point2f> >& true_points_group_copy,
+                   vector<Point2f>& tmp_localization_points);
+    void deleteUsedPoints(vector<vector<Point2f> >& true_points_group, vector<vector<Point2f> >& loc,
+                          vector<Point2f>& tmp_localization_points);
+    void fixationPoints(vector<Point2f> &local_point);
+    bool checkPoints(const vector<Point2f>& quadrangle_points);
+    bool checkPointsInsideQuadrangle(const vector<Point2f>& quadrangle_points);
+    bool checkPointsInsideTriangle(const vector<Point2f>& triangle_points);
+
+    Mat bin_barcode_fullsize, bin_barcode_temp;
+    vector<Point2f> not_resized_loc_points;
+    vector<Point2f> resized_loc_points;
+    vector< vector< Point2f > > localization_points, transformation_points;
+    struct compareDistanse_y
+    {
+        bool operator()(const Point2f& a, const Point2f& b) const
+        {
+            return a.y < b.y;
+        }
+    };
+    struct compareSquare
+    {
+        const vector<Point2f>& points;
+        compareSquare(const vector<Point2f>& points_) : points(points_) {}
+        bool operator()(const Vec3i& a, const Vec3i& b) const;
+    };
+    Mat original;
+    class ParallelSearch : public ParallelLoopBody
+    {
+    public:
+        ParallelSearch(vector< vector< Point2f > >& true_points_group_,
+                vector< vector< Point2f > >& loc_, int iter_, int* end_,
+                vector< vector< Vec3i > >& all_points_,
+                QRDetectMulti& cl_)
+        :
+            true_points_group(true_points_group_),
+            loc(loc_),
+            iter(iter_),
+            end(end_),
+            all_points(all_points_),
+            cl(cl_)
+        {
+        }
+        void operator()(const Range& range) const CV_OVERRIDE;
+        vector< vector< Point2f > >& true_points_group;
+        vector< vector< Point2f > >& loc;
+        int iter;
+        int* end;
+        vector< vector< Vec3i > >& all_points;
+        QRDetectMulti& cl;
+    };
+};
+
+void QRDetectMulti::ParallelSearch::operator()(const Range& range) const
+{
+    for (int s = range.start; s < range.end; s++)
+    {
+        bool flag = false;
+        for (int r = iter; r < end[s]; r++)
+        {
+            if (flag)
+                break;
+
+            size_t x = iter + s;
+            size_t k = r - iter;
+            vector<Point2f> triangle;
+
+            for (int l = 0; l < 3; l++)
+            {
+                triangle.push_back(true_points_group[s][all_points[s][k][l]]);
+            }
+
+            if (cl.checkPointsInsideTriangle(triangle))
+            {
+                bool flag_for_break = false;
+                cl.fixationPoints(triangle);
+                if (triangle.size() == 3)
+                {
+                    cl.localization_points[x] = triangle;
+                    if (cl.purpose == cl.SHRINKING)
+                    {
+
+                        for (size_t j = 0; j < 3; j++)
+                        {
+                            cl.localization_points[x][j] *= cl.coeff_expansion;
+                        }
+                    }
+                    else if (cl.purpose == cl.ZOOMING)
+                    {
+                        for (size_t j = 0; j < 3; j++)
+                        {
+                            cl.localization_points[x][j] /= cl.coeff_expansion;
+                        }
+                    }
+                    for (size_t i = 0; i < 3; i++)
+                    {
+                        for (size_t j = i + 1; j < 3; j++)
+                        {
+                            if (norm(cl.localization_points[x][i] - cl.localization_points[x][j]) < 10)
+                            {
+                                cl.localization_points[x].clear();
+                                flag_for_break = true;
+                                break;
+                            }
+                        }
+                        if (flag_for_break)
+                            break;
+                    }
+                    if ((!flag_for_break)
+                            && (cl.localization_points[x].size() == 3)
+                            && (cl.computeTransformationPoints(x))
+                            && (cl.checkPointsInsideQuadrangle(cl.transformation_points[x]))
+                            && (cl.checkPoints(cl.transformation_points[x])))
+                    {
+                        for (int l = 0; l < 3; l++)
+                        {
+                            loc[s][all_points[s][k][l]].x = -1;
+                        }
+
+                        flag = true;
+                        break;
+                    }
+                }
+                if (flag)
+                {
+                    break;
+                }
+                else
+                {
+                    cl.transformation_points[x].clear();
+                    cl.localization_points[x].clear();
+                }
+            }
+        }
+    }
+}
+
+void QRDetectMulti::init(const Mat& src, double eps_vertical_, double eps_horizontal_)
+{
+    CV_TRACE_FUNCTION();
+
+    CV_Assert(!src.empty());
+    const double min_side = std::min(src.size().width, src.size().height);
+    if (min_side < 512.0)
+    {
+        purpose = ZOOMING;
+        coeff_expansion = 512.0 / min_side;
+        const int width  = cvRound(src.size().width  * coeff_expansion);
+        const int height = cvRound(src.size().height  * coeff_expansion);
+        Size new_size(width, height);
+        resize(src, barcode, new_size, 0, 0, INTER_LINEAR);
+    }
+    else if (min_side > 512.0)
+    {
+        purpose = SHRINKING;
+        coeff_expansion = min_side / 512.0;
+        const int width  = cvRound(src.size().width  / coeff_expansion);
+        const int height = cvRound(src.size().height  / coeff_expansion);
+        Size new_size(width, height);
+        resize(src, barcode, new_size, 0, 0, INTER_AREA);
+    }
+    else
+    {
+        purpose = UNCHANGED;
+        coeff_expansion = 1.0;
+        barcode = src.clone();
+    }
+
+    eps_vertical   = eps_vertical_;
+    eps_horizontal = eps_horizontal_;
+    adaptiveThreshold(barcode, bin_barcode, 255, ADAPTIVE_THRESH_GAUSSIAN_C, THRESH_BINARY, 83, 2);
+    adaptiveThreshold(src, bin_barcode_fullsize, 255, ADAPTIVE_THRESH_GAUSSIAN_C, THRESH_BINARY, 83, 2);
+}
+
+void QRDetectMulti::fixationPoints(vector<Point2f> &local_point)
+{
+    CV_TRACE_FUNCTION();
+
+    Point2f v0(local_point[1] - local_point[2]);
+    Point2f v1(local_point[0] - local_point[2]);
+    Point2f v2(local_point[1] - local_point[0]);
+
+    double cos_angles[3], norm_triangl[3];
+    norm_triangl[0] = norm(v0);
+    norm_triangl[1] = norm(v1);
+    norm_triangl[2] = norm(v2);
+
+    cos_angles[0] = v2.dot(-v1) / (norm_triangl[1] * norm_triangl[2]);
+    cos_angles[1] = v2.dot(v0) / (norm_triangl[0] * norm_triangl[2]);
+    cos_angles[2] = v1.dot(v0) / (norm_triangl[0] * norm_triangl[1]);
+
+    const double angle_barrier = 0.85;
+    if (fabs(cos_angles[0]) > angle_barrier || fabs(cos_angles[1]) > angle_barrier || fabs(cos_angles[2]) > angle_barrier)
+    {
+        local_point.clear();
+        return;
+    }
+
+    size_t i_min_cos =
+            (cos_angles[0] < cos_angles[1] && cos_angles[0] < cos_angles[2]) ? 0 :
+                    (cos_angles[1] < cos_angles[0] && cos_angles[1] < cos_angles[2]) ? 1 : 2;
+
+    size_t index_max = 0;
+    double max_area = std::numeric_limits<double>::min();
+    for (size_t i = 0; i < local_point.size(); i++)
+    {
+        const size_t current_index = i % 3;
+        const size_t left_index  = (i + 1) % 3;
+        const size_t right_index = (i + 2) % 3;
+
+        const Point2f current_point(local_point[current_index]);
+        const Point2f left_point(local_point[left_index]);
+        const Point2f right_point(local_point[right_index]);
+        const Point2f central_point(intersectionLines(
+                current_point,
+                Point2f(static_cast<float>((local_point[left_index].x + local_point[right_index].x) * 0.5),
+                        static_cast<float>((local_point[left_index].y + local_point[right_index].y) * 0.5)),
+                Point2f(0, static_cast<float>(bin_barcode_temp.rows - 1)),
+                Point2f(static_cast<float>(bin_barcode_temp.cols - 1),
+                        static_cast<float>(bin_barcode_temp.rows - 1))));
+
+
+        vector<Point2f> list_area_pnt;
+        list_area_pnt.push_back(current_point);
+
+        vector<LineIterator> list_line_iter;
+        list_line_iter.push_back(LineIterator(bin_barcode_temp, current_point, left_point));
+        list_line_iter.push_back(LineIterator(bin_barcode_temp, current_point, central_point));
+        list_line_iter.push_back(LineIterator(bin_barcode_temp, current_point, right_point));
+
+        for (size_t k = 0; k < list_line_iter.size(); k++)
+        {
+            LineIterator& li = list_line_iter[k];
+            uint8_t future_pixel = 255, count_index = 0;
+            for (int j = 0; j < li.count; j++, ++li)
+            {
+                Point p = li.pos();
+                if (p.x >= bin_barcode_temp.cols ||
+                    p.y >= bin_barcode_temp.rows)
+                {
+                    break;
+                }
+
+                const uint8_t value = bin_barcode_temp.at<uint8_t>(p);
+                if (value == future_pixel)
+                {
+                    future_pixel = static_cast<uint8_t>(~future_pixel);
+                    count_index++;
+                    if (count_index == 3)
+                    {
+                        list_area_pnt.push_back(p);
+                        break;
+                    }
+                }
+            }
+        }
+
+        const double temp_check_area = contourArea(list_area_pnt);
+        if (temp_check_area > max_area)
+        {
+            index_max = current_index;
+            max_area = temp_check_area;
+        }
+
+    }
+    if (index_max == i_min_cos)
+    {
+        std::swap(local_point[0], local_point[index_max]);
+    }
+    else
+    {
+        local_point.clear();
+        return;
+    }
+
+    const Point2f rpt = local_point[0], bpt = local_point[1], gpt = local_point[2];
+    Matx22f m(rpt.x - bpt.x, rpt.y - bpt.y, gpt.x - rpt.x, gpt.y - rpt.y);
+    if (determinant(m) > 0)
+    {
+        std::swap(local_point[1], local_point[2]);
+    }
 }
+
+bool QRDetectMulti::checkPoints(const vector<Point2f>& quadrangle_points)
+{
+    if (quadrangle_points.size() != 4)
+        return false;
+    vector<Point2f> quadrangle = quadrangle_points;
+    std::sort(quadrangle.begin(), quadrangle.end(), compareDistanse_y());
+    LineIterator it1(bin_barcode_fullsize, quadrangle[1], quadrangle[0]);
+    LineIterator it2(bin_barcode_fullsize, quadrangle[2], quadrangle[0]);
+    LineIterator it3(bin_barcode_fullsize, quadrangle[1], quadrangle[3]);
+    LineIterator it4(bin_barcode_fullsize, quadrangle[2], quadrangle[3]);
+    vector<LineIterator> list_line_iter;
+    list_line_iter.push_back(it1);
+    list_line_iter.push_back(it2);
+    list_line_iter.push_back(it3);
+    list_line_iter.push_back(it4);
+    int count_w = 0;
+    int count_b = 0;
+    for (int j = 0; j < 3; j +=2)
+    {
+        LineIterator& li = list_line_iter[j];
+        LineIterator& li2 = list_line_iter[j + 1];
+        for (int i = 0; i < li.count; i++)
+        {
+
+            Point pt1 = li.pos();
+            Point pt2 = li2.pos();
+            LineIterator it0(bin_barcode_fullsize, pt1, pt2);
+            for (int r = 0; r < it0.count; r++)
+            {
+                int pixel = bin_barcode.at<uchar>(it0.pos().y , it0.pos().x);
+                if (pixel == 255)
+                {
+                    count_w++;
+                }
+                if (pixel == 0)
+                {
+                    count_b++;
+                }
+                it0++;
+            }
+            li++;
+            li2++;
+        }
+    }
+
+    double frac = double(count_b) / double(count_w);
+    double bottom_bound = 0.76;
+    double upper_bound = 1.24;
+    if ((frac <= bottom_bound) || (frac >= upper_bound))
+        return false;
+    return true;
+}
+
+bool QRDetectMulti::checkPointsInsideQuadrangle(const vector<Point2f>& quadrangle_points)
+{
+    if (quadrangle_points.size() != 4)
+        return false;
+
+    int count = 0;
+    for (size_t i = 0; i < not_resized_loc_points.size(); i++)
+    {
+        if (pointPolygonTest(quadrangle_points, not_resized_loc_points[i], true) > 0)
+        {
+            count++;
+        }
+    }
+    if (count == 3)
+        return true;
+    else
+        return false;
+}
+
+bool QRDetectMulti::checkPointsInsideTriangle(const vector<Point2f>& triangle_points)
+{
+    if (triangle_points.size() != 3)
+        return false;
+    double eps = 3;
+    for (size_t i = 0; i < resized_loc_points.size(); i++)
+    {
+        if (pointPolygonTest( triangle_points, resized_loc_points[i], true ) > 0)
+        {
+            if ((abs(resized_loc_points[i].x - triangle_points[0].x) > eps)
+                    && (abs(resized_loc_points[i].x - triangle_points[1].x) > eps)
+                    && (abs(resized_loc_points[i].x - triangle_points[2].x) > eps))
+            {
+                return false;
+            }
+        }
+    }
+    return true;
+}
+
+bool QRDetectMulti::compareSquare::operator()(const Vec3i& a, const Vec3i& b) const
+{
+    Point2f a0 = points[a[0]];
+    Point2f a1 = points[a[1]];
+    Point2f a2 = points[a[2]];
+    Point2f b0 = points[b[0]];
+    Point2f b1 = points[b[1]];
+    Point2f b2 = points[b[2]];
+    return fabs((a1.x - a0.x) * (a2.y - a0.y) - (a2.x - a0.x) * (a1.y - a0.y)) <
+           fabs((b1.x - b0.x) * (b2.y - b0.y) - (b2.x - b0.x) * (b1.y - b0.y));
+}
+
+int QRDetectMulti::findNumberLocalizationPoints(vector<Point2f>& tmp_localization_points)
+{
+    size_t number_possible_purpose = 1;
+    if (purpose == SHRINKING)
+        number_possible_purpose = 2;
+    Mat tmp_shrinking = bin_barcode;
+    int tmp_num_points = 0;
+    int num_points = -1;
+    for (eps_horizontal = 0.1; eps_horizontal < 0.4; eps_horizontal += 0.1)
+    {
+        tmp_num_points = 0;
+        num_points = -1;
+        if (purpose == SHRINKING)
+            number_possible_purpose = 2;
+        else
+            number_possible_purpose = 1;
+        for (size_t k = 0; k < number_possible_purpose; k++)
+        {
+            if (k == 1)
+                bin_barcode = bin_barcode_fullsize;
+            vector<Vec3d> list_lines_x = searchHorizontalLines();
+            if (list_lines_x.empty())
+            {
+                if (k == 0)
+                {
+                    k = 1;
+                    bin_barcode = bin_barcode_fullsize;
+                    list_lines_x = searchHorizontalLines();
+                    if (list_lines_x.empty())
+                        break;
+                }
+                else
+                    break;
+            }
+            vector<Point2f> list_lines_y = extractVerticalLines(list_lines_x, eps_horizontal);
+            if (list_lines_y.size() < 3)
+            {
+                if (k == 0)
+                {
+                    k = 1;
+                    bin_barcode = bin_barcode_fullsize;
+                    list_lines_x = searchHorizontalLines();
+                    if (list_lines_x.empty())
+                        break;
+                    list_lines_y = extractVerticalLines(list_lines_x, eps_horizontal);
+                    if (list_lines_y.size() < 3)
+                        break;
+                }
+                else
+                    break;
+            }
+            vector<int> index_list_lines_y;
+            for (size_t i = 0; i < list_lines_y.size(); i++)
+                index_list_lines_y.push_back(-1);
+            num_points = 0;
+            for (size_t i = 0; i < list_lines_y.size() - 1; i++)
+            {
+                for (size_t j = i; j < list_lines_y.size(); j++ )
+                {
+
+                    double points_distance = norm(list_lines_y[i] - list_lines_y[j]);
+                    if (points_distance <= 10)
+                    {
+                        if ((index_list_lines_y[i] == -1) && (index_list_lines_y[j] == -1))
+                        {
+                            index_list_lines_y[i] = num_points;
+                            index_list_lines_y[j] = num_points;
+                            num_points++;
+                        }
+                        else if (index_list_lines_y[i] != -1)
+                            index_list_lines_y[j] = index_list_lines_y[i];
+                        else if (index_list_lines_y[j] != -1)
+                            index_list_lines_y[i] = index_list_lines_y[j];
+                    }
+                }
+            }
+            for (size_t i = 0; i < index_list_lines_y.size(); i++)
+            {
+                if (index_list_lines_y[i] == -1)
+                {
+                    index_list_lines_y[i] = num_points;
+                    num_points++;
+                }
+            }
+            if ((tmp_num_points < num_points) && (k == 1))
+            {
+                purpose = UNCHANGED;
+                tmp_num_points = num_points;
+                bin_barcode = bin_barcode_fullsize;
+                coeff_expansion = 1.0;
+            }
+            if ((tmp_num_points < num_points) && (k == 0))
+            {
+                tmp_num_points = num_points;
+            }
+        }
+
+        if ((tmp_num_points < 3) && (tmp_num_points >= 1))
+        {
+            const double min_side = std::min(bin_barcode_fullsize.size().width, bin_barcode_fullsize.size().height);
+            if (min_side > 512)
+            {
+                bin_barcode = tmp_shrinking;
+                purpose = SHRINKING;
+                coeff_expansion = min_side / 512.0;
+            }
+            if (min_side < 512)
+            {
+                bin_barcode = tmp_shrinking;
+                purpose = ZOOMING;
+                coeff_expansion = 512 / min_side;
+            }
+        }
+        else
+            break;
+    }
+    if (purpose == SHRINKING)
+        bin_barcode = tmp_shrinking;
+    num_points = tmp_num_points;
+    vector<Vec3d> list_lines_x = searchHorizontalLines();
+    if (list_lines_x.empty())
+        return num_points;
+    vector<Point2f> list_lines_y = extractVerticalLines(list_lines_x, eps_horizontal);
+    if (list_lines_y.size() < 3)
+        return num_points;
+    if (num_points < 3)
+        return num_points;
+
+    Mat labels;
+    kmeans(list_lines_y, num_points, labels,
+            TermCriteria( TermCriteria::EPS + TermCriteria::COUNT, 10, 0.1),
+            num_points, KMEANS_PP_CENTERS, tmp_localization_points);
+    bin_barcode_temp = bin_barcode.clone();
+    if (purpose == SHRINKING)
+    {
+        const int width  = cvRound(bin_barcode.size().width  * coeff_expansion);
+        const int height = cvRound(bin_barcode.size().height * coeff_expansion);
+        Size new_size(width, height);
+        Mat intermediate;
+        resize(bin_barcode, intermediate, new_size, 0, 0, INTER_LINEAR);
+        bin_barcode = intermediate.clone();
+    }
+    else if (purpose == ZOOMING)
+    {
+        const int width  = cvRound(bin_barcode.size().width  / coeff_expansion);
+        const int height = cvRound(bin_barcode.size().height / coeff_expansion);
+        Size new_size(width, height);
+        Mat intermediate;
+        resize(bin_barcode, intermediate, new_size, 0, 0, INTER_LINEAR);
+        bin_barcode = intermediate.clone();
+    }
+    else
+    {
+        bin_barcode = bin_barcode_fullsize.clone();
+    }
+    return num_points;
+}
+
+void QRDetectMulti::findQRCodeContours(vector<Point2f>& tmp_localization_points,
+                                      vector< vector< Point2f > >& true_points_group, const int& num_qrcodes)
+{
+    Mat gray, blur_image, threshold_output;
+    Mat bar = barcode;
+    const int width  = cvRound(bin_barcode.size().width);
+    const int height = cvRound(bin_barcode.size().height);
+    Size new_size(width, height);
+    resize(bar, bar, new_size, 0, 0, INTER_LINEAR);
+    blur(bar, blur_image, Size(3, 3));
+    threshold(blur_image, threshold_output, 50, 255, THRESH_BINARY);
+
+    vector< vector< Point > > contours;
+    vector<Vec4i> hierarchy;
+    findContours(threshold_output, contours, hierarchy, RETR_TREE, CHAIN_APPROX_SIMPLE, Point(0, 0));
+    vector<Point2f> all_contours_points;
+    for (size_t i = 0; i < contours.size(); i++)
+    {
+        for (size_t j = 0; j < contours[i].size(); j++)
+        {
+            all_contours_points.push_back(contours[i][j]);
+        }
+    }
+    Mat qrcode_labels;
+    vector<Point2f> clustered_localization_points;
+    int count_contours = num_qrcodes;
+    if (all_contours_points.size() < size_t(num_qrcodes))
+        count_contours = (int)all_contours_points.size();
+    kmeans(all_contours_points, count_contours, qrcode_labels,
+          TermCriteria( TermCriteria::EPS + TermCriteria::COUNT, 10, 0.1),
+          count_contours, KMEANS_PP_CENTERS, clustered_localization_points);
+
+    vector< vector< Point2f > > qrcode_clusters(count_contours);
+    for (int i = 0; i < count_contours; i++)
+        for (int j = 0; j < int(all_contours_points.size()); j++)
+        {
+            if (qrcode_labels.at<int>(j, 0) == i)
+            {
+                qrcode_clusters[i].push_back(all_contours_points[j]);
+            }
+        }
+    vector< vector< Point2f > > hull(count_contours);
+    for (size_t i = 0; i < qrcode_clusters.size(); i++)
+        convexHull(Mat(qrcode_clusters[i]), hull[i]);
+    not_resized_loc_points = tmp_localization_points;
+    resized_loc_points = tmp_localization_points;
+    if (purpose == SHRINKING)
+    {
+        for (size_t j = 0; j < not_resized_loc_points.size(); j++)
+        {
+            not_resized_loc_points[j] *= coeff_expansion;
+        }
+    }
+    else if (purpose == ZOOMING)
+    {
+        for (size_t j = 0; j < not_resized_loc_points.size(); j++)
+        {
+            not_resized_loc_points[j] /= coeff_expansion;
+        }
+    }
+
+    true_points_group.resize(hull.size());
+
+    for (size_t j = 0; j < hull.size(); j++)
+    {
+        for (size_t i = 0; i < not_resized_loc_points.size(); i++)
+        {
+            if (pointPolygonTest(hull[j], not_resized_loc_points[i], true) > 0)
+            {
+                true_points_group[j].push_back(tmp_localization_points[i]);
+                tmp_localization_points[i].x = -1;
+            }
+
+        }
+    }
+    vector<Point2f> copy;
+    for (size_t j = 0; j < tmp_localization_points.size(); j++)
+    {
+       if (tmp_localization_points[j].x != -1)
+            copy.push_back(tmp_localization_points[j]);
+    }
+    tmp_localization_points = copy;
+}
+
+bool QRDetectMulti::checkSets(vector<vector<Point2f> >& true_points_group, vector<vector<Point2f> >& true_points_group_copy,
+                              vector<Point2f>& tmp_localization_points)
+{
+    for (size_t i = 0; i < true_points_group.size(); i++)
+    {
+        if (true_points_group[i].size() < 3)
+        {
+            for (size_t j = 0; j < true_points_group[i].size(); j++)
+                tmp_localization_points.push_back(true_points_group[i][j]);
+            true_points_group[i].clear();
+        }
+    }
+    vector< vector< Point2f > > temp_for_copy;
+    for (size_t i = 0; i < true_points_group.size(); i++)
+    {
+        if (true_points_group[i].size() != 0)
+            temp_for_copy.push_back(true_points_group[i]);
+    }
+    true_points_group = temp_for_copy;
+    if (true_points_group.size() == 0)
+    {
+        true_points_group.push_back(tmp_localization_points);
+        tmp_localization_points.clear();
+    }
+    if (true_points_group.size() == 0)
+        return false;
+    if (true_points_group[0].size() < 3)
+        return false;
+
+
+    int* set_size = new int[true_points_group.size()];
+    for (size_t i = 0; i < true_points_group.size(); i++)
+    {
+        set_size[i] = int(0.5 * (true_points_group[i].size() - 2 ) * (true_points_group[i].size() - 1));
+    }
+    vector< vector< Vec3i > > all_points(true_points_group.size());
+    for (size_t i = 0; i < true_points_group.size(); i++)
+        all_points[i].resize(set_size[i]);
+    int cur_cluster = 0;
+    for (size_t i = 0; i < true_points_group.size(); i++)
+    {
+        cur_cluster = 0;
+        for (size_t j = 1; j < true_points_group[i].size() - 1; j++)
+            for (size_t k = j + 1; k < true_points_group[i].size(); k++)
+            {
+                all_points[i][cur_cluster][0] = 0;
+                all_points[i][cur_cluster][1] = int(j);
+                all_points[i][cur_cluster][2] = int(k);
+                cur_cluster++;
+            }
+    }
+
+    for (size_t i = 0; i < true_points_group.size(); i++)
+    {
+        std::sort(all_points[i].begin(), all_points[i].end(), compareSquare(true_points_group[i]));
+    }
+    if (true_points_group.size() == 1)
+    {
+        int check_number = 35;
+        if (set_size[0] > check_number)
+            set_size[0] = check_number;
+        all_points[0].resize(set_size[0]);
+    }
+    int iter = (int)localization_points.size();
+    localization_points.resize(iter + true_points_group.size());
+    transformation_points.resize(iter + true_points_group.size());
+
+    true_points_group_copy = true_points_group;
+    int* end = new int[true_points_group.size()];
+    for (size_t i = 0; i < true_points_group.size(); i++)
+        end[i] = iter + set_size[i];
+    ParallelSearch parallelSearch(true_points_group,
+            true_points_group_copy, iter, end, all_points, *this);
+    parallel_for_(Range(0, (int)true_points_group.size()), parallelSearch);
+
+    return true;
+}
+
+void QRDetectMulti::deleteUsedPoints(vector<vector<Point2f> >& true_points_group, vector<vector<Point2f> >& loc,
+                                     vector<Point2f>& tmp_localization_points)
+{
+    size_t iter = localization_points.size() - true_points_group.size() ;
+    for (size_t s = 0; s < true_points_group.size(); s++)
+    {
+        if (localization_points[iter + s].empty())
+            loc[s][0].x = -2;
+
+        if (loc[s].size() == 3)
+        {
+
+            if ((true_points_group.size() > 1) || ((true_points_group.size() == 1) && (tmp_localization_points.size() != 0)) )
+            {
+                for (size_t j = 0; j < true_points_group[s].size(); j++)
+                {
+                    if (loc[s][j].x != -1)
+                    {
+                        loc[s][j].x = -1;
+                        tmp_localization_points.push_back(true_points_group[s][j]);
+                    }
+                }
+            }
+        }
+        vector<Point2f> for_copy;
+        for (size_t j = 0; j < loc[s].size(); j++)
+        {
+            if ((loc[s][j].x != -1) && (loc[s][j].x != -2) )
+            {
+                for_copy.push_back(true_points_group[s][j]);
+            }
+            if ((loc[s][j].x == -2) && (true_points_group.size() > 1))
+            {
+                tmp_localization_points.push_back(true_points_group[s][j]);
+            }
+        }
+        true_points_group[s] = for_copy;
+    }
+
+    vector< vector< Point2f > > for_copy_loc;
+    vector< vector< Point2f > > for_copy_trans;
+
+
+    for (size_t i = 0; i < localization_points.size(); i++)
+    {
+        if ((localization_points[i].size() == 3) && (transformation_points[i].size() == 4))
+        {
+            for_copy_loc.push_back(localization_points[i]);
+            for_copy_trans.push_back(transformation_points[i]);
+        }
+    }
+    localization_points = for_copy_loc;
+    transformation_points = for_copy_trans;
+}
+
+bool QRDetectMulti::localization()
+{
+    CV_TRACE_FUNCTION();
+    vector<Point2f> tmp_localization_points;
+    int num_points = findNumberLocalizationPoints(tmp_localization_points);
+    if (num_points < 3)
+        return false;
+    int num_qrcodes = divUp(num_points, 3);
+    vector<vector<Point2f> > true_points_group;
+    findQRCodeContours(tmp_localization_points, true_points_group, num_qrcodes);
+    for (int q = 0; q < num_qrcodes; q++)
+    {
+       vector<vector<Point2f> > loc;
+       size_t iter = localization_points.size();
+
+       if (!checkSets(true_points_group, loc, tmp_localization_points))
+            break;
+       deleteUsedPoints(true_points_group, loc, tmp_localization_points);
+       if ((localization_points.size() - iter) == 1)
+           q--;
+       if (((localization_points.size() - iter) == 0) && (tmp_localization_points.size() == 0) && (true_points_group.size() == 1) )
+            break;
+    }
+    if ((transformation_points.size() == 0) || (localization_points.size() == 0))
+       return false;
+    return true;
+}
+
+bool QRDetectMulti::computeTransformationPoints(const size_t cur_ind)
+{
+    CV_TRACE_FUNCTION();
+
+    if (localization_points[cur_ind].size() != 3)
+    {
+        return false;
+    }
+
+    vector<Point> locations, non_zero_elem[3], newHull;
+    vector<Point2f> new_non_zero_elem[3];
+    for (size_t i = 0; i < 3 ; i++)
+    {
+        Mat mask = Mat::zeros(bin_barcode.rows + 2, bin_barcode.cols + 2, CV_8UC1);
+        uint8_t next_pixel, future_pixel = 255;
+        int localization_point_x = cvRound(localization_points[cur_ind][i].x);
+        int localization_point_y = cvRound(localization_points[cur_ind][i].y);
+        int count_test_lines = 0, index = localization_point_x;
+        for (; index < bin_barcode.cols - 1; index++)
+        {
+            next_pixel = bin_barcode.at<uint8_t>(localization_point_y, index + 1);
+            if (next_pixel == future_pixel)
+            {
+                future_pixel = static_cast<uint8_t>(~future_pixel);
+                count_test_lines++;
+
+                if (count_test_lines == 2)
+                {
+                    // TODO avoid drawing functions
+                    floodFill(bin_barcode, mask,
+                            Point(index + 1, localization_point_y), 255,
+                            0, Scalar(), Scalar(), FLOODFILL_MASK_ONLY);
+                    break;
+                }
+            }
+
+        }
+        Mat mask_roi = mask(Range(1, bin_barcode.rows - 1), Range(1, bin_barcode.cols - 1));
+        findNonZero(mask_roi, non_zero_elem[i]);
+        newHull.insert(newHull.end(), non_zero_elem[i].begin(), non_zero_elem[i].end());
+    }
+    convexHull(newHull, locations);
+    for (size_t i = 0; i < locations.size(); i++)
+    {
+        for (size_t j = 0; j < 3; j++)
+        {
+            for (size_t k = 0; k < non_zero_elem[j].size(); k++)
+            {
+                if (locations[i] == non_zero_elem[j][k])
+                {
+                    new_non_zero_elem[j].push_back(locations[i]);
+                }
+            }
+        }
+    }
+
+    if (new_non_zero_elem[0].size() == 0)
+        return false;
+
+    double pentagon_diag_norm = -1;
+    Point2f down_left_edge_point, up_right_edge_point, up_left_edge_point;
+    for (size_t i = 0; i < new_non_zero_elem[1].size(); i++)
+    {
+        for (size_t j = 0; j < new_non_zero_elem[2].size(); j++)
+        {
+            double temp_norm = norm(new_non_zero_elem[1][i] - new_non_zero_elem[2][j]);
+            if (temp_norm > pentagon_diag_norm)
+            {
+                down_left_edge_point = new_non_zero_elem[1][i];
+                up_right_edge_point  = new_non_zero_elem[2][j];
+                pentagon_diag_norm = temp_norm;
+            }
+        }
+    }
+
+    if (down_left_edge_point == Point2f(0, 0) ||
+        up_right_edge_point  == Point2f(0, 0))
+    {
+        return false;
+    }
+
+    double max_area = -1;
+    up_left_edge_point = new_non_zero_elem[0][0];
+
+    for (size_t i = 0; i < new_non_zero_elem[0].size(); i++)
+    {
+        vector<Point2f> list_edge_points;
+        list_edge_points.push_back(new_non_zero_elem[0][i]);
+        list_edge_points.push_back(down_left_edge_point);
+        list_edge_points.push_back(up_right_edge_point);
+
+        double temp_area = fabs(contourArea(list_edge_points));
+        if (max_area < temp_area)
+        {
+            up_left_edge_point = new_non_zero_elem[0][i];
+            max_area = temp_area;
+        }
+    }
+
+    Point2f down_max_delta_point, up_max_delta_point;
+    double norm_down_max_delta = -1, norm_up_max_delta = -1;
+    for (size_t i = 0; i < new_non_zero_elem[1].size(); i++)
+    {
+        double temp_norm_delta = norm(up_left_edge_point - new_non_zero_elem[1][i]) + norm(down_left_edge_point - new_non_zero_elem[1][i]);
+        if (norm_down_max_delta < temp_norm_delta)
+        {
+            down_max_delta_point = new_non_zero_elem[1][i];
+            norm_down_max_delta = temp_norm_delta;
+        }
+    }
+
+
+    for (size_t i = 0; i < new_non_zero_elem[2].size(); i++)
+    {
+        double temp_norm_delta = norm(up_left_edge_point - new_non_zero_elem[2][i]) + norm(up_right_edge_point - new_non_zero_elem[2][i]);
+        if (norm_up_max_delta < temp_norm_delta)
+        {
+            up_max_delta_point = new_non_zero_elem[2][i];
+            norm_up_max_delta = temp_norm_delta;
+        }
+    }
+    vector<Point2f> tmp_transformation_points;
+    tmp_transformation_points.push_back(down_left_edge_point);
+    tmp_transformation_points.push_back(up_left_edge_point);
+    tmp_transformation_points.push_back(up_right_edge_point);
+    tmp_transformation_points.push_back(intersectionLines(
+                    down_left_edge_point, down_max_delta_point,
+                    up_right_edge_point, up_max_delta_point));
+    transformation_points[cur_ind] = tmp_transformation_points;
+
+    vector<Point2f> quadrilateral = getQuadrilateral(transformation_points[cur_ind]);
+    transformation_points[cur_ind] = quadrilateral;
+
+    return true;
+}
+
+bool QRCodeDetector::detectMulti(InputArray in, OutputArray points) const
+{
+    Mat inarr;
+    if (!checkQRInputImage(in, inarr))
+    {
+        points.release();
+        return false;
+    }
+
+    QRDetectMulti qrdet;
+    qrdet.init(inarr, p->epsX, p->epsY);
+    if (!qrdet.localization())
+    {
+        points.release();
+        return false;
+    }
+    vector< vector< Point2f > > pnts2f = qrdet.getTransformationPoints();
+    vector<Point2f> trans_points;
+    for(size_t i = 0; i < pnts2f.size(); i++)
+        for(size_t j = 0; j < pnts2f[i].size(); j++)
+            trans_points.push_back(pnts2f[i][j]);
+
+    updatePointsResult(points, trans_points);
+
+    return true;
+}
+
+class ParallelDecodeProcess : public ParallelLoopBody
+{
+public:
+    ParallelDecodeProcess(Mat& inarr_, vector<QRDecode>& qrdec_, vector<std::string>& decoded_info_,
+            vector<Mat>& straight_barcode_, vector< vector< Point2f > >& src_points_)
+        : inarr(inarr_), qrdec(qrdec_), decoded_info(decoded_info_)
+        , straight_barcode(straight_barcode_), src_points(src_points_)
+    {
+        // nothing
+    }
+    void operator()(const Range& range) const CV_OVERRIDE
+    {
+        for (int i = range.start; i < range.end; i++)
+        {
+            qrdec[i].init(inarr, src_points[i]);
+            bool ok = qrdec[i].fullDecodingProcess();
+            if (ok)
+            {
+                decoded_info[i] = qrdec[i].getDecodeInformation();
+                straight_barcode[i] = qrdec[i].getStraightBarcode();
+            }
+            else if (std::min(inarr.size().width, inarr.size().height) > 512)
+            {
+                const int min_side = std::min(inarr.size().width, inarr.size().height);
+                double coeff_expansion = min_side / 512;
+                const int width  = cvRound(inarr.size().width  / coeff_expansion);
+                const int height = cvRound(inarr.size().height / coeff_expansion);
+                Size new_size(width, height);
+                Mat inarr2;
+                resize(inarr, inarr2, new_size, 0, 0, INTER_AREA);
+                for (size_t j = 0; j < 4; j++)
+                {
+                    src_points[i][j] /= static_cast<float>(coeff_expansion);
+                }
+                qrdec[i].init(inarr2, src_points[i]);
+                ok = qrdec[i].fullDecodingProcess();
+                if (ok)
+                {
+                    decoded_info[i] = qrdec[i].getDecodeInformation();
+                    straight_barcode[i] = qrdec[i].getStraightBarcode();
+                }
+            }
+            if (decoded_info[i].empty())
+                decoded_info[i] = "";
+        }
+    }
+
+private:
+    Mat& inarr;
+    vector<QRDecode>& qrdec;
+    vector<std::string>& decoded_info;
+    vector<Mat>& straight_barcode;
+    vector< vector< Point2f > >& src_points;
+
+};
+
+bool QRCodeDetector::decodeMulti(
+        InputArray img,
+        InputArray points,
+        CV_OUT std::vector<cv::String>& decoded_info,
+        OutputArrayOfArrays straight_qrcode
+    ) const
+{
+    Mat inarr;
+    if (!checkQRInputImage(img, inarr))
+        return false;
+    CV_Assert(points.size().width > 0);
+    CV_Assert((points.size().width % 4) == 0);
+    vector< vector< Point2f > > src_points ;
+    Mat qr_points = points.getMat();
+    for (int i = 0; i < points.size().width ; i += 4)
+    {
+        vector<Point2f> tempMat = qr_points.colRange(i, i + 4);
+        if (contourArea(tempMat) > 0.0)
+        {
+            src_points.push_back(tempMat);
+        }
+    }
+    CV_Assert(src_points.size() > 0);
+    vector<QRDecode> qrdec(src_points.size());
+    vector<Mat> straight_barcode(src_points.size());
+    vector<std::string> info(src_points.size());
+    ParallelDecodeProcess parallelDecodeProcess(inarr, qrdec, info, straight_barcode, src_points);
+    parallel_for_(Range(0, int(src_points.size())), parallelDecodeProcess);
+    vector<Mat> for_copy;
+    for (size_t i = 0; i < straight_barcode.size(); i++)
+    {
+        if (!(straight_barcode[i].empty()))
+            for_copy.push_back(straight_barcode[i]);
+    }
+    straight_barcode = for_copy;
+    vector<Mat> tmp_straight_qrcodes;
+    if (straight_qrcode.needed())
+    {
+        for (size_t i = 0; i < straight_barcode.size(); i++)
+        {
+            Mat tmp_straight_qrcode;
+            tmp_straight_qrcodes.push_back(tmp_straight_qrcode);
+            straight_barcode[i].convertTo(((OutputArray)tmp_straight_qrcodes[i]),
+                                             ((OutputArray)tmp_straight_qrcodes[i]).fixedType() ?
+                                             ((OutputArray)tmp_straight_qrcodes[i]).type() : CV_32FC2);
+        }
+        straight_qrcode.createSameSize(tmp_straight_qrcodes, CV_32FC2);
+        straight_qrcode.assign(tmp_straight_qrcodes);
+    }
+    decoded_info.clear();
+    for (size_t i = 0; i < info.size(); i++)
+    {
+       decoded_info.push_back(info[i]);
+    }
+    if (!decoded_info.empty())
+        return true;
+    else
+        return false;
+}
+
+bool QRCodeDetector::detectAndDecodeMulti(
+        InputArray img,
+        CV_OUT std::vector<cv::String>& decoded_info,
+        OutputArray points_,
+        OutputArrayOfArrays straight_qrcode
+    ) const
+{
+    Mat inarr;
+    if (!checkQRInputImage(img, inarr))
+    {
+        points_.release();
+        return false;
+    }
+
+    vector<Point2f> points;
+    bool ok = detectMulti(inarr, points);
+    if (!ok)
+    {
+        points_.release();
+        return false;
+    }
+    updatePointsResult(points_, points);
+    decoded_info.clear();
+    ok = decodeMulti(inarr, points, decoded_info, straight_qrcode);
+    return ok;
+}
+
+}  // namespace
diff --git a/modules/objdetect/test/test_qrcode.cpp b/modules/objdetect/test/test_qrcode.cpp
index 8c02f3db0c..d26323ea76 100644
--- a/modules/objdetect/test/test_qrcode.cpp
+++ b/modules/objdetect/test/test_qrcode.cpp
@@ -21,7 +21,11 @@ std::string qrcode_images_close[] = {
 std::string qrcode_images_monitor[] = {
   "monitor_1.png", "monitor_2.png", "monitor_3.png", "monitor_4.png", "monitor_5.png"
 };
-// #define UPDATE_QRCODE_TEST_DATA
+std::string qrcode_images_multiple[] = {
+  "2_qrcodes.png", "3_close_qrcodes.png", "3_qrcodes.png", "4_qrcodes.png",
+   "5_qrcodes.png", "6_qrcodes.png", "7_qrcodes.png", "8_close_qrcodes.png"
+};
+//#define UPDATE_QRCODE_TEST_DATA
 #ifdef  UPDATE_QRCODE_TEST_DATA
 
 TEST(Objdetect_QRCode, generate_test_data)
@@ -134,6 +138,66 @@ TEST(Objdetect_QRCode_Monitor, generate_test_data)
     file_config.release();
 }
 
+
+TEST(Objdetect_QRCode_Multi, generate_test_data)
+{
+    const std::string root = "qrcode/multiple/";
+    const std::string dataset_config = findDataFile(root + "dataset_config.json");
+    FileStorage file_config(dataset_config, FileStorage::WRITE);
+
+    file_config << "multiple_images" << "[:";
+    size_t multiple_count = sizeof(qrcode_images_multiple) / sizeof(qrcode_images_multiple[0]);
+    for (size_t i = 0; i < multiple_count; i++)
+    {
+        file_config << "{:" << "image_name" << qrcode_images_multiple[i];
+        std::string image_path = findDataFile(root + qrcode_images_multiple[i]);
+        Mat src = imread(image_path);
+
+        ASSERT_FALSE(src.empty()) << "Can't read image: " << image_path;
+        std::vector<Point> corners;
+        EXPECT_TRUE(detectQRCodeMulti(src, corners));
+#ifdef HAVE_QUIRC
+        std::vector<cv::String> decoded_info;
+        std::vector<Mat> straight_barcode;
+        EXPECT_TRUE(decodeQRCodeMulti(src, corners, decoded_info, straight_barcode));
+#endif
+        file_config << "x" << "[:";
+        for(size_t j = 0; j < corners.size(); j += 4)
+        {
+            file_config << "[:";
+            for (size_t k = 0; k < 4; k++)
+            {
+                file_config << corners[j + k].x;
+            }
+            file_config << "]";
+        }
+        file_config << "]";
+        file_config << "y" << "[:";
+        for(size_t j = 0; j < corners.size(); j += 4)
+        {
+            file_config << "[:";
+            for (size_t k = 0; k < 4; k++)
+            {
+                file_config << corners[j + k].y;
+            }
+            file_config << "]";
+        }
+        file_config << "]";
+        file_config << "info";
+        file_config << "[:";
+
+        for(size_t j = 0; j < decoded_info.size(); j++)
+        {
+            file_config << decoded_info[j];
+        }
+        file_config << "]";
+        file_config << "}";
+    }
+
+    file_config << "]";
+    file_config.release();
+}
+
 #else
 
 typedef testing::TestWithParam< std::string > Objdetect_QRCode;
@@ -326,9 +390,96 @@ TEST_P(Objdetect_QRCode_Monitor, regression)
     }
 }
 
+typedef testing::TestWithParam < std::string > Objdetect_QRCode_Multi;
+TEST_P(Objdetect_QRCode_Multi, regression)
+{
+    const std::string name_current_image = GetParam();
+    const std::string root = "qrcode/multiple/";
+    const int pixels_error = 3;
+
+    std::string image_path = findDataFile(root + name_current_image);
+    Mat src = imread(image_path);
+    ASSERT_FALSE(src.empty()) << "Can't read image: " << image_path;
+    QRCodeDetector qrcode;
+    std::vector<Point> corners;
+#ifdef HAVE_QUIRC
+    std::vector<cv::String> decoded_info;
+    std::vector<Mat> straight_barcode;
+    EXPECT_TRUE(qrcode.detectAndDecodeMulti(src, decoded_info, corners, straight_barcode));
+    ASSERT_FALSE(corners.empty());
+    ASSERT_FALSE(decoded_info.empty());
+#else
+    ASSERT_TRUE(qrcode.detectMulti(src, corners));
+#endif
+
+    const std::string dataset_config = findDataFile(root + "dataset_config.json");
+    FileStorage file_config(dataset_config, FileStorage::READ);
+    ASSERT_TRUE(file_config.isOpened()) << "Can't read validation data: " << dataset_config;
+    {
+        FileNode images_list = file_config["multiple_images"];
+        size_t images_count = static_cast<size_t>(images_list.size());
+        ASSERT_GT(images_count, 0u) << "Can't find validation data entries in 'test_images': " << dataset_config;
+        for (size_t index = 0; index < images_count; index++)
+        {
+            FileNode config = images_list[(int)index];
+            std::string name_test_image = config["image_name"];
+            if (name_test_image == name_current_image)
+            {
+                for(int j = 0; j < int(corners.size()); j += 4)
+                {
+                    bool ok = false;
+                    for (int k = 0; k < int(corners.size() / 4); k++)
+                    {
+                        int count_eq_points = 0;
+                        for (int i = 0; i < 4; i++)
+                        {
+                            int x = config["x"][k][i];
+                            int y = config["y"][k][i];
+                            if(((abs(corners[j + i].x - x)) <= pixels_error) && ((abs(corners[j + i].y - y)) <= pixels_error))
+                              count_eq_points++;
+                        }
+                        if (count_eq_points == 4)
+                        {
+                            ok = true;
+                            break;
+                        }
+                    }
+                    EXPECT_TRUE(ok);
+                }
+
+#ifdef HAVE_QUIRC
+                  size_t count_eq_info = 0;
+                  for(int i = 0; i < int(decoded_info.size()); i++)
+                  {
+                      for(int j = 0; j < int(decoded_info.size()); j++)
+                      {
+                          std::string original_info = config["info"][j];
+                          if(original_info == decoded_info[i])
+                          {
+                             count_eq_info++;
+                             break;
+                          }
+                      }
+                  }
+                  EXPECT_EQ(decoded_info.size(), count_eq_info);
+#endif
+
+                  return; // done
+            }
+        }
+        std::cerr
+            << "Not found results for '" << name_current_image
+            << "' image in config file:" << dataset_config << std::endl
+            << "Re-run tests with enabled UPDATE_QRCODE_TEST_DATA macro to update test data."
+            << std::endl;
+    }
+}
+
+
 INSTANTIATE_TEST_CASE_P(/**/, Objdetect_QRCode, testing::ValuesIn(qrcode_images_name));
 INSTANTIATE_TEST_CASE_P(/**/, Objdetect_QRCode_Close, testing::ValuesIn(qrcode_images_close));
 INSTANTIATE_TEST_CASE_P(/**/, Objdetect_QRCode_Monitor, testing::ValuesIn(qrcode_images_monitor));
+INSTANTIATE_TEST_CASE_P(/**/, Objdetect_QRCode_Multi, testing::ValuesIn(qrcode_images_multiple));
 
 TEST(Objdetect_QRCode_basic, not_found_qrcode)
 {
diff --git a/modules/python/src2/cv2.cpp b/modules/python/src2/cv2.cpp
index 0b8788f899..1aa3e14640 100644
--- a/modules/python/src2/cv2.cpp
+++ b/modules/python/src2/cv2.cpp
@@ -319,6 +319,7 @@ typedef std::vector<std::vector<Mat> > vector_vector_Mat;
 typedef std::vector<UMat> vector_UMat;
 typedef std::vector<DMatch> vector_DMatch;
 typedef std::vector<String> vector_String;
+typedef std::vector<std::string> vector_string;
 typedef std::vector<Scalar> vector_Scalar;
 
 typedef std::vector<std::vector<char> > vector_vector_char;
diff --git a/modules/videoio/src/cap_ffmpeg_impl.hpp b/modules/videoio/src/cap_ffmpeg_impl.hpp
index 984408d86f..0e0af395f4 100644
--- a/modules/videoio/src/cap_ffmpeg_impl.hpp
+++ b/modules/videoio/src/cap_ffmpeg_impl.hpp
@@ -967,6 +967,29 @@ bool CvCapture_FFMPEG::open( const char* _filename )
         enc->thread_count = get_number_of_cpus();
 //#endif
 
+#if LIBAVCODEC_BUILD >= CALC_FFMPEG_VERSION(52, 123, 0)
+        AVDictionaryEntry* avdiscard_entry = av_dict_get(dict, "avdiscard", NULL, 0);
+
+        if (avdiscard_entry != 0) {
+            if(strcmp(avdiscard_entry->value, "all") == 0)
+                enc->skip_frame = AVDISCARD_ALL;
+            else if (strcmp(avdiscard_entry->value, "bidir") == 0)
+                enc->skip_frame = AVDISCARD_BIDIR;
+            else if (strcmp(avdiscard_entry->value, "default") == 0)
+                enc->skip_frame = AVDISCARD_DEFAULT;
+            else if (strcmp(avdiscard_entry->value, "none") == 0)
+                enc->skip_frame = AVDISCARD_NONE;
+#if LIBAVCODEC_BUILD >= CALC_FFMPEG_VERSION(54, 59, 100)
+            else if (strcmp(avdiscard_entry->value, "nonintra") == 0)
+                enc->skip_frame = AVDISCARD_NONINTRA;
+#endif
+            else if (strcmp(avdiscard_entry->value, "nonkey") == 0)
+                enc->skip_frame = AVDISCARD_NONKEY;
+            else if (strcmp(avdiscard_entry->value, "nonref") == 0)
+                enc->skip_frame = AVDISCARD_NONREF;
+        }
+#endif
+
 #if LIBAVFORMAT_BUILD < CALC_FFMPEG_VERSION(53, 2, 0)
 #define AVMEDIA_TYPE_VIDEO CODEC_TYPE_VIDEO
 #endif
diff --git a/modules/videoio/test/test_ffmpeg.cpp b/modules/videoio/test/test_ffmpeg.cpp
index f769b5c5dd..7b1bfe403d 100644
--- a/modules/videoio/test/test_ffmpeg.cpp
+++ b/modules/videoio/test/test_ffmpeg.cpp
@@ -180,6 +180,54 @@ const videoio_container_params_t videoio_container_params[] =
 
 INSTANTIATE_TEST_CASE_P(/**/, videoio_container, testing::ValuesIn(videoio_container_params));
 
+typedef tuple<string, string, int> videoio_skip_params_t;
+typedef testing::TestWithParam< videoio_skip_params_t > videoio_skip;
+
+TEST_P(videoio_skip, DISABLED_read)  // optional test, may fail in some configurations
+{
+#if CV_VERSION_MAJOR >= 4
+    if (!videoio_registry::hasBackend(CAP_FFMPEG))
+        throw SkipTestException("Backend was not found");
+#endif
+
+    const string path = get<0>(GetParam());
+    const string env = get<1>(GetParam());
+    const int expectedFrameNumber = get<2>(GetParam());
+
+    #ifdef _WIN32
+        _putenv_s("OPENCV_FFMPEG_CAPTURE_OPTIONS", env.c_str());
+    #else
+        setenv("OPENCV_FFMPEG_CAPTURE_OPTIONS", env.c_str(), 1);
+    #endif
+    VideoCapture container(findDataFile(path), CAP_FFMPEG);
+    #ifdef _WIN32
+        _putenv_s("OPENCV_FFMPEG_CAPTURE_OPTIONS", "");
+    #else
+        setenv("OPENCV_FFMPEG_CAPTURE_OPTIONS", "", 1);
+    #endif
+
+    ASSERT_TRUE(container.isOpened());
+
+    Mat reference;
+    int nframes = 0, n_err = 0;
+    while (container.isOpened())
+    {
+        if (container.read(reference))
+            nframes++;
+        else if (++n_err > 3)
+            break;
+    }
+    EXPECT_EQ(expectedFrameNumber, nframes);
+}
+
+const videoio_skip_params_t videoio_skip_params[] =
+{
+    videoio_skip_params_t("video/big_buck_bunny.mp4", "", 125),
+    videoio_skip_params_t("video/big_buck_bunny.mp4", "avdiscard;nonkey", 11)
+};
+
+INSTANTIATE_TEST_CASE_P(/**/, videoio_skip, testing::ValuesIn(videoio_skip_params));
+
 //==========================================================================
 
 static void generateFrame(Mat &frame, unsigned int i, const Point &center, const Scalar &color)
diff --git a/platforms/android/build_sdk.py b/platforms/android/build_sdk.py
index 6a52be7d29..9c3624313f 100755
--- a/platforms/android/build_sdk.py
+++ b/platforms/android/build_sdk.py
@@ -230,6 +230,9 @@ class Builder:
         if self.debug_info:  # Release with debug info
             cmake_vars['BUILD_WITH_DEBUG_INFO'] = "ON"
 
+        if self.config.modules_list is not None:
+            cmd.append("-DBUILD_LIST='%s'" % self.config.modules_list)
+
         if self.config.extra_modules_path is not None:
             cmd.append("-DOPENCV_EXTRA_MODULES_PATH='%s'" % self.config.extra_modules_path)
 
@@ -319,6 +322,7 @@ if __name__ == "__main__":
     parser.add_argument('--ndk_path', help="Path to Android NDK to use for build")
     parser.add_argument('--sdk_path', help="Path to Android SDK to use for build")
     parser.add_argument('--use_android_buildtools', action="store_true", help='Use cmake/ninja build tools from Android SDK')
+    parser.add_argument("--modules_list", help="List of  modules to include for build")
     parser.add_argument("--extra_modules_path", help="Path to extra modules to use for build")
     parser.add_argument('--sign_with', help="Certificate to sign the Manager apk")
     parser.add_argument('--build_doc', action="store_true", help="Build javadoc")
diff --git a/samples/cpp/qrcode.cpp b/samples/cpp/qrcode.cpp
index 1e938f66f1..af332d307c 100644
--- a/samples/cpp/qrcode.cpp
+++ b/samples/cpp/qrcode.cpp
@@ -2,23 +2,45 @@
 #include "opencv2/imgproc.hpp"
 #include "opencv2/highgui.hpp"
 #include "opencv2/videoio.hpp"
+#include "opencv2/imgcodecs.hpp"
 #include <string>
 #include <iostream>
 
 using namespace std;
 using namespace cv;
 
-static void drawQRCodeContour(Mat &color_image, vector<Point> transform);
-static void drawFPS(Mat &color_image, double fps);
-static int  liveQRCodeDetect(const string& out_file);
-static int  imageQRCodeDetect(const string& in_file, const string& out_file);
+static int liveQRCodeDetect();
+static int imageQRCodeDetect(const string& in_file);
+
+static bool g_modeMultiQR = false;
+static bool g_detectOnly = false;
+
+static string g_out_file_name, g_out_file_ext;
+static int g_save_idx = 0;
+
+static bool g_saveDetections = false;
+static bool g_saveAll = false;
+
+static string getQRModeString()
+{
+    std::ostringstream out;
+    out << "QR"
+        << (g_modeMultiQR ? " multi" : "")
+        << (g_detectOnly ? " detector" : " decoder");
+    return out.str();
+}
 
 int main(int argc, char *argv[])
 {
     const string keys =
         "{h help ? |        | print help messages }"
-        "{i in     |        | input  path to file for detect (with parameter - show image, otherwise - camera)}"
-        "{o out    |        | output path to file (save image, work with -i parameter) }";
+        "{i in     |        | input image path (also switches to image detection mode) }"
+        "{detect   | false  | detect QR code only (skip decoding) }"
+        "{m multi  |        | use detect for multiple qr-codes }"
+        "{o out    | qr_code.png | path to result file }"
+        "{save_detections | false  | save all QR detections (video mode only) }"
+        "{save_all | false  | save all processed frames  (video mode only) }"
+    ;
     CommandLineParser cmd_parser(argc, argv, keys);
 
     cmd_parser.about("This program detects the QR-codes from camera or images using the OpenCV library.");
@@ -28,32 +50,51 @@ int main(int argc, char *argv[])
         return 0;
     }
 
-    string in_file_name  = cmd_parser.get<string>("in");    // input  path to image
-    string out_file_name;
-    if (cmd_parser.has("out"))
-        out_file_name = cmd_parser.get<string>("out");   // output path to image
+    string in_file_name = cmd_parser.get<string>("in");    // path to input image
 
+    if (cmd_parser.has("out"))
+    {
+        std::string fpath = cmd_parser.get<string>("out");   // path to output image
+        std::string::size_type idx = fpath.rfind('.');
+        if (idx != std::string::npos)
+        {
+            g_out_file_name = fpath.substr(0, idx);
+            g_out_file_ext = fpath.substr(idx);
+        }
+        else
+        {
+            g_out_file_name = fpath;
+            g_out_file_ext = ".png";
+        }
+    }
     if (!cmd_parser.check())
     {
         cmd_parser.printErrors();
         return -1;
     }
 
+    g_modeMultiQR = cmd_parser.has("multi") && cmd_parser.get<bool>("multi");
+    g_detectOnly = cmd_parser.has("detect") && cmd_parser.get<bool>("detect");
+
+    g_saveDetections = cmd_parser.has("save_detections") && cmd_parser.get<bool>("save_detections");
+    g_saveAll = cmd_parser.has("save_all") && cmd_parser.get<bool>("save_all");
+
     int return_code = 0;
     if (in_file_name.empty())
     {
-        return_code = liveQRCodeDetect(out_file_name);
+        return_code = liveQRCodeDetect();
     }
     else
     {
-        return_code = imageQRCodeDetect(samples::findFile(in_file_name), out_file_name);
+        return_code = imageQRCodeDetect(samples::findFile(in_file_name));
     }
     return return_code;
 }
 
-void drawQRCodeContour(Mat &color_image, vector<Point> transform)
+static
+void drawQRCodeContour(Mat &color_image, const vector<Point>& corners)
 {
-    if (!transform.empty())
+    if (!corners.empty())
     {
         double show_radius = (color_image.rows  > color_image.cols)
                    ? (2.813 * color_image.rows) / color_image.cols
@@ -61,127 +102,246 @@ void drawQRCodeContour(Mat &color_image, vector<Point> transform)
         double contour_radius = show_radius * 0.4;
 
         vector< vector<Point> > contours;
-        contours.push_back(transform);
+        contours.push_back(corners);
         drawContours(color_image, contours, 0, Scalar(211, 0, 148), cvRound(contour_radius));
 
         RNG rng(1000);
         for (size_t i = 0; i < 4; i++)
         {
             Scalar color = Scalar(rng.uniform(0,255), rng.uniform(0, 255), rng.uniform(0, 255));
-            circle(color_image, transform[i], cvRound(show_radius), color, -1);
+            circle(color_image, corners[i], cvRound(show_radius), color, -1);
         }
     }
 }
 
+static
 void drawFPS(Mat &color_image, double fps)
 {
     ostringstream convert;
-    convert << cvRound(fps) << " FPS (QR detection)";
+    convert << cv::format("%.2f", fps) << " FPS (" << getQRModeString() << ")";
     putText(color_image, convert.str(), Point(25, 25), FONT_HERSHEY_DUPLEX, 1, Scalar(0, 0, 255), 2);
 }
 
-int liveQRCodeDetect(const string& out_file)
+static
+void drawQRCodeResults(Mat& frame, const vector<Point>& corners, const vector<cv::String>& decode_info, double fps)
+{
+    if (!corners.empty())
+    {
+        for (size_t i = 0; i < corners.size(); i += 4)
+        {
+            size_t qr_idx = i / 4;
+            vector<Point> qrcode_contour(corners.begin() + i, corners.begin() + i + 4);
+            drawQRCodeContour(frame, qrcode_contour);
+
+            cout << "QR[" << qr_idx << "] @ " << Mat(qrcode_contour).reshape(2, 1) << ": ";
+            if (decode_info.size() > qr_idx)
+            {
+                if (!decode_info[qr_idx].empty())
+                    cout << "'" << decode_info[qr_idx] << "'" << endl;
+                else
+                    cout << "can't decode QR code" << endl;
+            }
+            else
+            {
+                cout << "decode information is not available (disabled)" << endl;
+            }
+        }
+    }
+    else
+    {
+        cout << "QR code is not detected" << endl;
+    }
+
+    drawFPS(frame, fps);
+}
+
+static
+void runQR(
+    QRCodeDetector& qrcode, const Mat& input,
+    vector<Point>& corners, vector<cv::String>& decode_info
+    // +global: bool g_modeMultiQR, bool g_detectOnly
+)
+{
+    if (!g_modeMultiQR)
+    {
+        if (!g_detectOnly)
+        {
+            String decode_info1 = qrcode.detectAndDecode(input, corners);
+            decode_info.push_back(decode_info1);
+        }
+        else
+        {
+            bool detection_result = qrcode.detect(input, corners);
+            CV_UNUSED(detection_result);
+        }
+    }
+    else
+    {
+        if (!g_detectOnly)
+        {
+            bool result_detection = qrcode.detectAndDecodeMulti(input, decode_info, corners);
+            CV_UNUSED(result_detection);
+        }
+        else
+        {
+            bool result_detection = qrcode.detectMulti(input, corners);
+            CV_UNUSED(result_detection);
+        }
+    }
+}
+
+static
+double processQRCodeDetection(QRCodeDetector& qrcode, const Mat& input, Mat& result, vector<Point>& corners)
+{
+    if (input.channels() == 1)
+        cvtColor(input, result, COLOR_GRAY2BGR);
+    else
+        input.copyTo(result);
+
+    cout << "Run " << getQRModeString()
+        << " on image: " << input.size() << " (" << typeToString(input.type()) << ")"
+        << endl;
+
+    TickMeter timer;
+
+    vector<cv::String> decode_info;
+    timer.start();
+    runQR(qrcode, input, corners, decode_info);
+    timer.stop();
+
+    double fps = 1 / timer.getTimeSec();
+    drawQRCodeResults(result, corners, decode_info, fps);
+
+    return fps;
+}
+
+int liveQRCodeDetect()
 {
     VideoCapture cap(0);
-    if(!cap.isOpened())
+
+    if (!cap.isOpened())
     {
         cout << "Cannot open a camera" << endl;
-        return -4;
+        return 2;
     }
 
+    cout << "Press 'm' to switch between detectAndDecode and detectAndDecodeMulti" << endl;
+    cout << "Press 'd' to switch between decoder and detector" << endl;
+    cout << "Press ' ' (space) to save result into images" << endl;
+    cout << "Press 'ESC' to exit" << endl;
     QRCodeDetector qrcode;
-    TickMeter total;
-    for(;;)
+
+    for (;;)
     {
-        Mat frame, src, straight_barcode;
-        string decode_info;
-        vector<Point> transform;
+        Mat frame;
         cap >> frame;
         if (frame.empty())
         {
             cout << "End of video stream" << endl;
             break;
         }
-        cvtColor(frame, src, COLOR_BGR2GRAY);
 
-        total.start();
-        bool result_detection = qrcode.detect(src, transform);
-        if (result_detection)
+        bool forceSave = g_saveAll;
+
+        Mat result;
+
+        try
+        {
+            vector<Point> corners;
+            double fps = processQRCodeDetection(qrcode, frame, result, corners);
+            cout << "FPS: " << fps << endl;
+            forceSave |= (g_saveDetections && !corners.empty());
+            //forceSave |= fps < 1.0;
+        }
+        catch (const cv::Exception& e)
         {
-            decode_info = qrcode.decode(src, transform, straight_barcode);
-            if (!decode_info.empty()) { cout << decode_info << endl; }
+            cerr << "ERROR exception: " << e.what() << endl;
+            forceSave = true;
         }
-        total.stop();
-        double fps = 1 / total.getTimeSec();
-        total.reset();
 
-        if (result_detection) { drawQRCodeContour(frame, transform); }
-        drawFPS(frame, fps);
+        if (!result.empty())
+            imshow("QR code", result);
+
+        int code = waitKey(1);
+        if (code < 0 && !forceSave)
+            continue; // timeout
+        char c = (char)code;
+        if (c == ' ' || forceSave)
+        {
+            string fsuffix = cv::format("-%05d", g_save_idx++);
+
+            string fname_input = g_out_file_name + fsuffix + "_input.png";
+            cout << "Saving QR code detection input: '" << fname_input << "' ..." << endl;
+            imwrite(fname_input, frame);
+
+            string fname = g_out_file_name + fsuffix + g_out_file_ext;
+            cout << "Saving QR code detection result: '" << fname << "' ..." << endl;
+            imwrite(fname, result);
 
-        imshow("Live QR code detector", frame);
-        char c = (char)waitKey(30);
+            cout << "Saved" << endl;
+        }
+        if (c == 'm')
+        {
+            g_modeMultiQR = !g_modeMultiQR;
+            cout << "Switching QR code mode ==> " << (g_modeMultiQR ? "detectAndDecodeMulti" : "detectAndDecode") << endl;
+        }
+        if (c == 'd')
+        {
+            g_detectOnly = !g_detectOnly;
+            cout << "Switching QR decoder mode ==> " << (g_detectOnly ? "detect" : "decode") << endl;
+        }
         if (c == 27)
+        {
+            cout << "'ESC' is pressed. Exiting..." << endl;
             break;
-        if (c == ' ' && !out_file.empty())
-            imwrite(out_file, frame); // TODO write original frame too
+        }
     }
+    cout << "Exit." << endl;
+
     return 0;
 }
 
-int imageQRCodeDetect(const string& in_file, const string& out_file)
+int imageQRCodeDetect(const string& in_file)
 {
-    Mat color_src = imread(in_file, IMREAD_COLOR), src;
-    cvtColor(color_src, src, COLOR_BGR2GRAY);
-    Mat straight_barcode;
-    string decoded_info;
-    vector<Point> transform;
     const int count_experiments = 10;
-    double transform_time = 0.0;
-    bool result_detection = false;
-    TickMeter total;
+
+    Mat input = imread(in_file, IMREAD_COLOR);
+    cout << "Run " << getQRModeString()
+        << " on image: " << input.size() << " (" << typeToString(input.type()) << ")"
+        << endl;
+
     QRCodeDetector qrcode;
+    vector<Point> corners;
+    vector<cv::String> decode_info;
+
+    TickMeter timer;
     for (size_t i = 0; i < count_experiments; i++)
     {
-        total.start();
-        transform.clear();
-        result_detection = qrcode.detect(src, transform);
-        total.stop();
-        transform_time += total.getTimeSec();
-        total.reset();
-        if (!result_detection)
-            continue;
-
-        total.start();
-        decoded_info = qrcode.decode(src, transform, straight_barcode);
-        total.stop();
-        transform_time += total.getTimeSec();
-        total.reset();
+        corners.clear();
+        decode_info.clear();
+
+        timer.start();
+        runQR(qrcode, input, corners, decode_info);
+        timer.stop();
     }
-    double fps = count_experiments / transform_time;
-    if (!result_detection)
-        cout << "QR code not found" << endl;
-    if (decoded_info.empty())
-        cout << "QR code cannot be decoded" << endl;
-
-    drawQRCodeContour(color_src, transform);
-    drawFPS(color_src, fps);
-
-    cout << "Input  image file path: " << in_file  << endl;
-    cout << "Output image file path: " << out_file << endl;
-    cout << "Size: " << color_src.size() << endl;
+    double fps = count_experiments / timer.getTimeSec();
     cout << "FPS: " << fps << endl;
-    cout << "Decoded info: " << decoded_info << endl;
 
-    if (!out_file.empty())
-    {
-        imwrite(out_file, color_src);
-    }
+    Mat result; input.copyTo(result);
+    drawQRCodeResults(result, corners, decode_info, fps);
+
+    imshow("QR", result); waitKey(1);
 
-    for(;;)
+    if (!g_out_file_name.empty())
     {
-        imshow("Detect QR code on image", color_src);
-        if (waitKey(0) == 27)
-            break;
+        string out_file = g_out_file_name + g_out_file_ext;
+        cout << "Saving result: " << out_file << endl;
+        imwrite(out_file, result);
     }
+
+    cout << "Press any key to exit ..." << endl;
+    waitKey(0);
+    cout << "Exit." << endl;
+
     return 0;
 }
diff --git a/samples/cpp/text_skewness_correction.cpp b/samples/cpp/text_skewness_correction.cpp
new file mode 100644
index 0000000000..15df92e641
--- /dev/null
+++ b/samples/cpp/text_skewness_correction.cpp
@@ -0,0 +1,74 @@
+/*
+This tutorial demonstrates how to correct the skewness in a text.
+The program takes as input a skewed source image and shows non skewed text.
+
+*/
+
+#include <opencv2/core.hpp>
+#include <opencv2/imgcodecs.hpp>
+#include <opencv2/highgui.hpp>
+#include <opencv2/imgproc.hpp>
+
+#include <iostream>
+#include <iomanip>
+#include <string>
+
+using namespace cv;
+using namespace std;
+
+
+int main( int argc, char** argv )
+{
+    CommandLineParser parser(argc, argv, "{@input | imageTextR.png | input image}");
+
+    // Load image from the disk
+    Mat image = imread( samples::findFile( parser.get<String>("@input") ), IMREAD_COLOR);
+    if (image.empty())
+    {
+        cout << "Cannot load the image " + parser.get<String>("@input") << endl;
+        return -1;
+    }
+
+    Mat gray;
+    cvtColor(image, gray, COLOR_BGR2GRAY);
+
+    //Threshold the image, setting all foreground pixels to 255 and all background pixels to 0
+    Mat thresh;
+    threshold(gray, thresh, 0, 255, THRESH_BINARY_INV | THRESH_OTSU);
+
+    // Applying erode filter to remove random noise
+    int erosion_size = 1;
+    Mat element = getStructuringElement( MORPH_RECT, Size(2*erosion_size+1, 2*erosion_size+1), Point(erosion_size, erosion_size) );
+    erode(thresh, thresh, element);
+
+    cv::Mat coords;
+    findNonZero(thresh, coords);
+
+    RotatedRect box = minAreaRect(coords);
+    float angle = box.angle;
+
+    // The cv::minAreaRect function returns values in the range [-90, 0)
+    // if the angle is less than -45 we need to add 90 to it
+    if (angle < -45.0f)
+    {
+        angle = (90.0f + angle);
+    }
+
+    //Obtaining the rotation matrix
+    Point2f center((image.cols) / 2.0f, (image.rows) / 2.0f);
+    Mat M = getRotationMatrix2D(center, angle, 1.0f);
+    Mat rotated;
+
+    // Rotating the image by required angle
+    stringstream angle_to_str;
+    angle_to_str << fixed << setprecision(2) << angle;
+    warpAffine(image, rotated, M, image.size(), INTER_CUBIC, BORDER_REPLICATE);
+    putText(rotated, "Angle " + angle_to_str.str() + " degrees", Point(10, 30), FONT_HERSHEY_SIMPLEX, 0.7, Scalar(0, 0, 255), 2);
+    cout << "[INFO] angle: " << angle_to_str.str() << endl;
+
+    //Show the image
+    imshow("Input", image);
+    imshow("Rotated", rotated);
+    waitKey(0);
+    return 0;
+}
diff --git a/samples/dnn/human_parsing.py b/samples/dnn/human_parsing.py
new file mode 100644
index 0000000000..c4ac11bad2
--- /dev/null
+++ b/samples/dnn/human_parsing.py
@@ -0,0 +1,178 @@
+#!/usr/bin/env python
+'''
+You can download the converted pb model from https://www.dropbox.com/s/qag9vzambhhkvxr/lip_jppnet_384.pb?dl=0
+or convert the model yourself.
+
+Follow these steps if you want to convert the original model yourself:
+    To get original .meta pre-trained model download https://drive.google.com/file/d/1BFVXgeln-bek8TCbRjN6utPAgRE0LJZg/view
+    For correct convert .meta to .pb model download original repository https://github.com/Engineering-Course/LIP_JPPNet
+    Change script evaluate_parsing_JPPNet-s2.py for human parsing
+    1. Remove preprocessing to create image_batch_origin:
+        with tf.name_scope("create_inputs"):
+        ...
+    Add
+        image_batch_origin = tf.placeholder(tf.float32, shape=(2, None, None, 3), name='input')
+
+    2. Create input
+        image = cv2.imread(path/to/image)
+        image_rev = np.flip(image, axis=1)
+        input = np.stack([image, image_rev], axis=0)
+
+    3. Hardcode image_h and image_w shapes to determine output shapes.
+       We use default INPUT_SIZE = (384, 384) from evaluate_parsing_JPPNet-s2.py.
+        parsing_out1 = tf.reduce_mean(tf.stack([tf.image.resize_images(parsing_out1_100, INPUT_SIZE),
+                                                tf.image.resize_images(parsing_out1_075, INPUT_SIZE),
+                                                tf.image.resize_images(parsing_out1_125, INPUT_SIZE)]), axis=0)
+       Do similarly with parsing_out2, parsing_out3
+    4. Remove postprocessing. Last net operation:
+        raw_output = tf.reduce_mean(tf.stack([parsing_out1, parsing_out2, parsing_out3]), axis=0)
+       Change:
+        parsing_ = sess.run(raw_output, feed_dict={'input:0': input})
+
+    5. To save model after sess.run(...) add:
+        input_graph_def = tf.get_default_graph().as_graph_def()
+        output_node = "Mean_3"
+        output_graph_def = tf.graph_util.convert_variables_to_constants(sess, input_graph_def, output_node)
+
+        output_graph = "LIP_JPPNet.pb"
+        with tf.gfile.GFile(output_graph, "wb") as f:
+            f.write(output_graph_def.SerializeToString())'
+'''
+
+import argparse
+import numpy as np
+import cv2 as cv
+
+
+backends = (cv.dnn.DNN_BACKEND_DEFAULT, cv.dnn.DNN_BACKEND_INFERENCE_ENGINE, cv.dnn.DNN_BACKEND_OPENCV)
+targets = (cv.dnn.DNN_TARGET_CPU, cv.dnn.DNN_TARGET_OPENCL, cv.dnn.DNN_TARGET_OPENCL_FP16, cv.dnn.DNN_TARGET_MYRIAD)
+
+
+def preprocess(image_path):
+    """
+    Create 4-dimensional blob from image and flip image
+    :param image_path: path to input image
+    """
+    image = cv.imread(image_path)
+    image_rev = np.flip(image, axis=1)
+    input = cv.dnn.blobFromImages([image, image_rev], mean=(104.00698793, 116.66876762, 122.67891434))
+    return input
+
+
+def run_net(input, model_path, backend, target):
+    """
+    Read network and infer model
+    :param model_path: path to JPPNet model
+    :param backend: computation backend
+    :param target: computation device
+    """
+    net = cv.dnn.readNet(model_path)
+    net.setPreferableBackend(backend)
+    net.setPreferableTarget(target)
+    net.setInput(input)
+    out = net.forward()
+    return out
+
+
+def postprocess(out, input_shape):
+    """
+    Create a grayscale human segmentation
+    :param out: network output
+    :param input_shape: input image width and height
+    """
+    # LIP classes
+    # 0 Background
+    # 1 Hat
+    # 2 Hair
+    # 3 Glove
+    # 4 Sunglasses
+    # 5 UpperClothes
+    # 6 Dress
+    # 7 Coat
+    # 8 Socks
+    # 9 Pants
+    # 10 Jumpsuits
+    # 11 Scarf
+    # 12 Skirt
+    # 13 Face
+    # 14 LeftArm
+    # 15 RightArm
+    # 16 LeftLeg
+    # 17 RightLeg
+    # 18 LeftShoe
+    # 19 RightShoe
+    head_output, tail_output = np.split(out, indices_or_sections=[1], axis=0)
+    head_output = head_output.squeeze(0)
+    tail_output = tail_output.squeeze(0)
+
+    head_output = np.stack([cv.resize(img, dsize=input_shape) for img in head_output[:, ...]])
+    tail_output = np.stack([cv.resize(img, dsize=input_shape) for img in tail_output[:, ...]])
+
+    tail_list = np.split(tail_output, indices_or_sections=list(range(1, 20)), axis=0)
+    tail_list = [arr.squeeze(0) for arr in tail_list]
+    tail_list_rev = [tail_list[i] for i in range(14)]
+    tail_list_rev.extend([tail_list[15], tail_list[14], tail_list[17], tail_list[16], tail_list[19], tail_list[18]])
+    tail_output_rev = np.stack(tail_list_rev, axis=0)
+    tail_output_rev = np.flip(tail_output_rev, axis=2)
+    raw_output_all = np.mean(np.stack([head_output, tail_output_rev], axis=0), axis=0, keepdims=True)
+    raw_output_all = np.argmax(raw_output_all, axis=1)
+    raw_output_all = raw_output_all.transpose(1, 2, 0)
+    return raw_output_all
+
+
+def decode_labels(gray_image):
+    """
+    Colorize image according to labels
+    :param gray_image: grayscale human segmentation result
+    """
+    height, width, _ = gray_image.shape
+    colors = [(0, 0, 0), (128, 0, 0), (255, 0, 0), (0, 85, 0), (170, 0, 51), (255, 85, 0),
+              (0, 0, 85), (0, 119, 221), (85, 85, 0), (0, 85, 85), (85, 51, 0), (52, 86, 128),
+              (0, 128, 0), (0, 0, 255), (51, 170, 221), (0, 255, 255),(85, 255, 170),
+              (170, 255, 85), (255, 255, 0), (255, 170, 0)]
+
+    segm = np.stack([colors[idx] for idx in gray_image.flatten()])
+    segm = segm.reshape(height, width, 3).astype(np.uint8)
+    segm = cv.cvtColor(segm, cv.COLOR_BGR2RGB)
+    return segm
+
+
+def parse_human(image_path, model_path, backend=cv.dnn.DNN_BACKEND_OPENCV, target=cv.dnn.DNN_TARGET_CPU):
+    """
+    Prepare input for execution, run net and postprocess output to parse human.
+    :param image_path: path to input image
+    :param model_path: path to JPPNet model
+    :param backend: name of computation backend
+    :param target: name of computation target
+    """
+    input = preprocess(image_path)
+    input_h, input_w = input.shape[2:]
+    output = run_net(input, model_path, backend, target)
+    grayscale_out = postprocess(output, (input_w, input_h))
+    segmentation = decode_labels(grayscale_out)
+    return segmentation
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(description='Use this script to run human parsing using JPPNet',
+                                     formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+    parser.add_argument('--input', '-i', required=True, help='Path to input image.')
+    parser.add_argument('--model', '-m', required=True, help='Path to pb model.')
+    parser.add_argument('--backend', choices=backends, default=cv.dnn.DNN_BACKEND_DEFAULT, type=int,
+                        help="Choose one of computation backends: "
+                             "%d: automatically (by default), "
+                             "%d: Intel's Deep Learning Inference Engine (https://software.intel.com/openvino-toolkit), "
+                             "%d: OpenCV implementation" % backends)
+    parser.add_argument('--target', choices=targets, default=cv.dnn.DNN_TARGET_CPU, type=int,
+                        help='Choose one of target computation devices: '
+                             '%d: CPU target (by default), '
+                             '%d: OpenCL, '
+                             '%d: OpenCL fp16 (half-float precision), '
+                             '%d: VPU' % targets)
+    args, _ = parser.parse_known_args()
+
+    output = parse_human(args.input, args.model, args.backend, args.target)
+    winName = 'Deep learning human parsing in OpenCV'
+    cv.namedWindow(winName, cv.WINDOW_AUTOSIZE)
+    cv.imshow(winName, output)
+    cv.waitKey()
diff --git a/samples/dnn/object_detection.py b/samples/dnn/object_detection.py
index 8126ee58aa..d4ea40f935 100644
--- a/samples/dnn/object_detection.py
+++ b/samples/dnn/object_detection.py
@@ -43,6 +43,7 @@ parser.add_argument('--target', choices=targets, default=cv.dnn.DNN_TARGET_CPU,
                          '%d: OpenCL fp16 (half-float precision), '
                          '%d: VPU' % targets)
 parser.add_argument('--async', type=int, default=0,
+                    dest='asyncN',
                     help='Number of asynchronous forwards at the same time. '
                          'Choose 0 for synchronous mode')
 args, _ = parser.parse_known_args()
@@ -231,8 +232,8 @@ def processingThreadBody():
         try:
             frame = framesQueue.get_nowait()
 
-            if args.async:
-                if len(futureOutputs) == args.async:
+            if args.asyncN:
+                if len(futureOutputs) == args.asyncN:
                     frame = None  # Skip the frame
             else:
                 framesQueue.queue.clear()  # Skip the rest of frames
@@ -256,7 +257,7 @@ def processingThreadBody():
                 frame = cv.resize(frame, (inpWidth, inpHeight))
                 net.setInput(np.array([[inpHeight, inpWidth, 1.6]], dtype=np.float32), 'im_info')
 
-            if args.async:
+            if args.asyncN:
                 futureOutputs.append(net.forwardAsync())
             else:
                 outs = net.forward(outNames)
diff --git a/samples/python/text_skewness_correction.py b/samples/python/text_skewness_correction.py
new file mode 100644
index 0000000000..c8ee33b39d
--- /dev/null
+++ b/samples/python/text_skewness_correction.py
@@ -0,0 +1,58 @@
+'''
+Text skewness correction
+This tutorial demonstrates how to correct the skewness in a text.
+The program takes as input a skewed source image and shows non skewed text.
+
+Usage:
+        python text_skewness_correction.py --image "Image path"
+'''
+
+import numpy as np
+import cv2 as cv
+import sys
+import argparse
+
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument("-i", "--image", required=True, help="path to input image file")
+    args = vars(parser.parse_args())
+
+    # load the image from disk
+    image = cv.imread(cv.samples.findFile(args["image"]))
+    if image is None:
+        print("can't read image " + args["image"])
+        sys.exit(-1)
+    gray = cv.cvtColor(image, cv.COLOR_BGR2GRAY)
+
+    # threshold the image, setting all foreground pixels to
+    # 255 and all background pixels to 0
+    thresh = cv.threshold(gray, 0, 255, cv.THRESH_BINARY_INV | cv.THRESH_OTSU)[1]
+
+    # Applying erode filter to remove random noise
+    erosion_size = 1
+    element = cv.getStructuringElement(cv.MORPH_RECT, (2 * erosion_size + 1, 2 * erosion_size + 1), (erosion_size, erosion_size) )
+    thresh = cv.erode(thresh, element)
+
+    coords = cv.findNonZero(thresh)
+    angle = cv.minAreaRect(coords)[-1]
+    # the `cv.minAreaRect` function returns values in the
+    # range [-90, 0) if the angle is less than -45 we need to add 90 to it
+    if angle < -45:
+        angle = (90 + angle)
+
+    (h, w) = image.shape[:2]
+    center = (w // 2, h // 2)
+    M = cv.getRotationMatrix2D(center, angle, 1.0)
+    rotated = cv.warpAffine(image, M, (w, h), flags=cv.INTER_CUBIC, borderMode=cv.BORDER_REPLICATE)
+    cv.putText(rotated, "Angle: {:.2f} degrees".format(angle), (10, 30), cv.FONT_HERSHEY_SIMPLEX, 0.7, (0, 0, 255), 2)
+
+    # show the output image
+    print("[INFO] angle: {:.2f}".format(angle))
+    cv.imshow("Input", image)
+    cv.imshow("Rotated", rotated)
+    cv.waitKey(0)
+
+
+if __name__ == "__main__":
+    main()