Multi-radix with kernel generation

modules/core/perf/opencl/perf_dxt.cpp

@@ -57,9 +57,9 @@ namespace ocl {
 typedef tuple<Size, int> DftParams;
 typedef TestBaseWithParam<DftParams> DftFixture;
 
-OCL_PERF_TEST_P(DftFixture, Dft, ::testing::Combine(Values(OCL_SIZE_1, OCL_SIZE_2, OCL_SIZE_3),
-                                                Values((int)DFT_ROWS, (int)DFT_SCALE, (int)DFT_INVERSE,
-                                                       (int)DFT_INVERSE | DFT_SCALE, (int)DFT_ROWS | DFT_INVERSE)))
+OCL_PERF_TEST_P(DftFixture, Dft, ::testing::Combine(Values(/*OCL_SIZE_1, OCL_SIZE_2, OCL_SIZE_3, */Size(1024, 1024), Size(1024, 2048), Size(512, 512), Size(2048, 2048)),
+                                                Values((int)DFT_ROWS/*, (int) 0/*, (int)DFT_SCALE, (int)DFT_INVERSE,
+                                                       (int)DFT_INVERSE | DFT_SCALE, (int)DFT_ROWS | DFT_INVERSE*/)))
 {
     const DftParams params = GetParam();
     const Size srcSize = get<0>(params);

modules/core/src/dxt.cpp

@@ -1960,7 +1960,7 @@ static void CL_CALLBACK oclCleanupCallback(cl_event e, cl_int, void *p)
 
 }
 
-static bool ocl_dft(InputArray _src, OutputArray _dst, int flags)
+static bool ocl_dft_amdfft(InputArray _src, OutputArray _dst, int flags)
 {
     int type = _src.type(), depth = CV_MAT_DEPTH(type), cn = CV_MAT_CN(type);
     Size ssize = _src.size();
@@ -2029,12 +2029,257 @@ static bool ocl_dft(InputArray _src, OutputArray _dst, int flags)
 
 #endif // HAVE_CLAMDFFT
 
+namespace cv
+{
+
+#ifdef HAVE_OPENCL
+
+static bool fft_radixN(InputArray _src, OutputArray _dst, int radix, int block_size, int nonzero_rows, int flags)
+{
+    int N = _src.size().width;
+    if (N % radix)
+        return false;
+
+    UMat src = _src.getUMat();
+    UMat dst = _dst.getUMat();
+
+    int thread_count = N / radix;
+    size_t globalsize[2] = { thread_count, nonzero_rows };
+    String kernel_name = format("fft_radix%d", radix);
+    ocl::Kernel k(kernel_name.c_str(), ocl::core::fft_oclsrc, (flags & DFT_INVERSE) != 0 ? "-D INVERSE" : "");
+    if (k.empty())
+        return false;
+
+    k.args(ocl::KernelArg::ReadOnlyNoSize(src), ocl::KernelArg::WriteOnlyNoSize(dst), block_size, thread_count, nonzero_rows);
+    return k.run(2, globalsize, NULL, false);
+}
+
+static bool ocl_packToCCS(InputArray _buffer, OutputArray _dst, int flags)
+{
+    UMat buffer = _buffer.getUMat();
+    UMat dst = _dst.getUMat();
+
+    buffer = buffer.reshape(1);
+    if ((flags & DFT_ROWS) == 0 && buffer.rows > 1)
+    {
+        // pack to CCS by rows
+        if (dst.cols > 2)
+            buffer.colRange(2, dst.cols + (dst.cols % 2)).copyTo(dst.colRange(1, dst.cols-1 + (dst.cols % 2)));
+
+        Mat dst_mat = dst.getMat(ACCESS_WRITE);
+        Mat buffer_mat = buffer.getMat(ACCESS_READ);
+
+        dst_mat.at<float>(0,0) = buffer_mat.at<float>(0,0);
+        dst_mat.at<float>(dst_mat.rows-1,0) = buffer_mat.at<float>(buffer.rows/2,0);
+        for (int i=1; i<dst_mat.rows-1; i+=2)
+        {
+            dst_mat.at<float>(i,0) = buffer_mat.at<float>((i+1)/2,0);
+            dst_mat.at<float>(i+1,0) = buffer_mat.at<float>((i+1)/2,1);
+        }
+
+        if (dst_mat.cols % 2 == 0)
+        {
+            dst_mat.at<float>(0,dst_mat.cols-1) = buffer_mat.at<float>(0,buffer.cols/2);
+            dst_mat.at<float>(dst_mat.rows-1,dst_mat.cols-1) = buffer_mat.at<float>(buffer.rows/2,buffer.cols/2);
+
+            for (int i=1; i<dst_mat.rows-1; i+=2)
+            {
+                dst_mat.at<float>(i,dst_mat.cols-1) = buffer_mat.at<float>((i+1)/2,buffer.cols/2);
+                dst_mat.at<float>(i+1,dst_mat.cols-1) = buffer_mat.at<float>((i+1)/2,buffer.cols/2+1);
+            }
+        }
+    } 
+    else
+    {
+        // pack to CCS each row
+        buffer.colRange(0,1).copyTo(dst.colRange(0,1));
+        buffer.colRange(2, (dst.cols+1)).copyTo(dst.colRange(1, dst.cols));
+    }
+    return true;
+}
+
+static bool ocl_dft_C2C_row(InputArray _src, OutputArray _dst, int nonzero_rows, int flags)
+{
+    int type = _src.type(), depth = CV_MAT_DEPTH(type), channels = CV_MAT_CN(type);
+    UMat src = _src.getUMat();
+
+    bool doubleSupport = ocl::Device::getDefault().doubleFPConfig() > 0;
+    if (depth == CV_64F && !doubleSupport)
+        return false;
+    
+    int factors[34];
+    int nf = DFTFactorize( src.cols, factors );
+    
+    int n = 1;
+    int factor_index = 0;
+    
+    String radix_processing;
+    int min_radix = INT_MAX;
+    // 1. 2^n transforms
+    if ( (factors[factor_index] & 1) == 0 )
+    {
+        for( ; n < factors[factor_index]; )
+        {
+            int radix = 2;
+            if (8*n <= factors[0])
+                radix = 8;
+            else if (4*n <= factors[0])
+                radix = 4;
+
+            radix_processing += format("fft_radix%d(smem,x,%d,%d);", radix, n,  src.cols/radix);
+            min_radix = min(radix, min_radix);
+            n *= radix;
+        }
+        factor_index++;
+    }
+
+    // 2. all the other transforms
+    for( ; factor_index < nf; factor_index++ )
+    {
+        int radix = factors[factor_index];
+        radix_processing += format("fft_radix%d(smem,x,%d,%d);", radix, n,  src.cols/radix);
+        min_radix = min(radix, min_radix);
+        n *= radix;
+    }
+
+    UMat dst = _dst.getUMat();
+
+    int thread_count = src.cols / min_radix;
+    size_t globalsize[2] = { thread_count, nonzero_rows };
+    size_t localsize[2] = { thread_count, 1 };
+
+    String buildOptions = format("-D LOCAL_SIZE=%d -D kercn=%d -D RADIX_PROCESS=%s",
+                                  src.cols, src.cols/thread_count, radix_processing.c_str());
+    ocl::Kernel k("fft_multi_radix", ocl::core::fft_oclsrc, buildOptions);
+    if (k.empty())
+        return false;
+
+    k.args(ocl::KernelArg::ReadOnlyNoSize(src), ocl::KernelArg::WriteOnlyNoSize(dst), thread_count, nonzero_rows);
+    return k.run(2, globalsize, localsize, false);
+}
+
+static bool ocl_dft(InputArray _src, OutputArray _dst, int flags, int nonzero_rows)
+{
+    int type = _src.type(), depth = CV_MAT_DEPTH(type), cn = CV_MAT_CN(type);
+    Size ssize = _src.size();
+    bool doubleSupport = ocl::Device::getDefault().doubleFPConfig() > 0;
+    if ( (!doubleSupport && depth == CV_64F) ||
+         !(type == CV_32FC1 || type == CV_32FC2 || type == CV_64FC1 || type == CV_64FC2))
+        return false;
+
+    // if is not a multiplication of prime numbers { 2, 3, 5 }
+    if (ssize.area() != getOptimalDFTSize(ssize.area()))
+        return false;
+
+    UMat src = _src.getUMat();
+    int complex_input = cn == 2 ? 1 : 0;
+    int complex_output = (flags & DFT_COMPLEX_OUTPUT) != 0;
+    int real_input = cn == 1 ? 1 : 0;
+    int real_output = (flags & DFT_REAL_OUTPUT) != 0;
+    bool inv = (flags & DFT_INVERSE) != 0 ? 1 : 0;
+    bool is1d = (flags & DFT_ROWS) != 0 || src.rows == 1;
+
+    // if output format is not specified
+    if (complex_output + real_output == 0)
+    {
+        if (!inv)
+        {
+            if (real_input)
+                real_output = 1;
+            else
+                complex_output = 1;
+        }
+    }
+
+    if (complex_output)
+    {
+        //if (is1d)
+        //    _dst.create(Size(src.cols/2+1, src.rows), CV_MAKE_TYPE(depth, 2));
+        //else
+            _dst.create(src.size(), CV_MAKE_TYPE(depth, 2));
+    }
+    else
+        _dst.create(src.size(), CV_MAKE_TYPE(depth, 1));
+    UMat dst = _dst.getUMat();
+
+    bool inplace = src.u == dst.u;
+    //UMat buffer;
+
+    //if (complex_input)
+    //{
+    //    if (inplace)
+    //        buffer = src;
+    //    else
+    //        src.copyTo(buffer);
+    //}
+    //else
+    //{
+    //    if (!inv)
+    //    {
+    //        // in case real input convert it to complex
+    //        buffer.create(src.size(), CV_MAKE_TYPE(depth, 2));
+    //        std::vector<UMat> planes;
+    //        planes.push_back(src);
+    //        planes.push_back(UMat::zeros(src.size(), CV_32F));
+    //        merge(planes, buffer);
+    //    } 
+    //    else
+    //    {
+    //        // TODO: unpack from CCS format
+    //    }
+    //}
+
+    if( nonzero_rows <= 0 || nonzero_rows > _src.rows() )
+        nonzero_rows = _src.rows();
+
+
+    if (!ocl_dft_C2C_row(src, dst, nonzero_rows, flags))
+        return false;
+
+    if ((flags & DFT_ROWS) == 0 && nonzero_rows > 1)
+    {
+        transpose(dst, dst);
+        if (!ocl_dft_C2C_row(dst, dst, dst.rows, flags))
+            return false;
+        transpose(dst, dst);
+    }
+
+    //if (complex_output)
+    //{
+    //    if (real_input && is1d)
+    //        _dst.assign(buffer.colRange(0, buffer.cols/2+1));
+    //    else
+    //        _dst.assign(buffer);
+    //}
+    //else
+    //{
+    //    if (!inv)
+    //        ocl_packToCCS(buffer, _dst, flags);
+    //    else
+    //    {
+    //        // copy real part to dst
+    //    }
+    //}
+    return true;
+}
+
+#endif
+
+} // namespace cv;
+
+
+
 void cv::dft( InputArray _src0, OutputArray _dst, int flags, int nonzero_rows )
 {
 #ifdef HAVE_CLAMDFFT
     CV_OCL_RUN(ocl::haveAmdFft() && ocl::Device::getDefault().type() != ocl::Device::TYPE_CPU &&
             _dst.isUMat() && _src0.dims() <= 2 && nonzero_rows == 0,
-               ocl_dft(_src0, _dst, flags))
+               ocl_dft_amdfft(_src0, _dst, flags))
+#endif
+
+#ifdef HAVE_OPENCL
+    CV_OCL_RUN(_dst.isUMat() && _src0.dims() <= 2,
+               ocl_dft(_src0, _dst, flags, nonzero_rows))
 #endif
 
     static DFTFunc dft_tbl[6] =
@@ -2046,10 +2291,8 @@ void cv::dft( InputArray _src0, OutputArray _dst, int flags, int nonzero_rows )
         (DFTFunc)RealDFT_64f,
         (DFTFunc)CCSIDFT_64f
     };
-
     AutoBuffer<uchar> buf;
     void *spec = 0;
-
     Mat src0 = _src0.getMat(), src = src0;
     int prev_len = 0, stage = 0;
     bool inv = (flags & DFT_INVERSE) != 0;
@@ -2058,6 +2301,7 @@ void cv::dft( InputArray _src0, OutputArray _dst, int flags, int nonzero_rows )
     int elem_size = (int)src.elemSize1(), complex_elem_size = elem_size*2;
     int factors[34];
     bool inplace_transform = false;
+    bool is1d = (flags & DFT_ROWS) != 0 || src.rows == 1;
 #ifdef USE_IPP_DFT
     AutoBuffer<uchar> ippbuf;
     int ipp_norm_flag = !(flags & DFT_SCALE) ? 8 : inv ? 2 : 1;
@@ -2066,7 +2310,10 @@ void cv::dft( InputArray _src0, OutputArray _dst, int flags, int nonzero_rows )
     CV_Assert( type == CV_32FC1 || type == CV_32FC2 || type == CV_64FC1 || type == CV_64FC2 );
 
     if( !inv && src.channels() == 1 && (flags & DFT_COMPLEX_OUTPUT) )
-        _dst.create( src.size(), CV_MAKETYPE(depth, 2) );
+        if (!is1d)
+            _dst.create( src.size(), CV_MAKETYPE(depth, 2) );
+        else
+            _dst.create( Size(src.cols/2+1, src.rows), CV_MAKETYPE(depth, 2) );
     else if( inv && src.channels() == 2 && (flags & DFT_REAL_OUTPUT) )
         _dst.create( src.size(), depth );
     else

modules/core/src/opencl/fft.cl

@@ -0,0 +1,297 @@
+__constant float PI = 3.14159265f;
+__constant float SQRT_2 = 0.707106781188f;
+
+__constant float sin_120 = 0.866025403784f;
+__constant float fft5_2 =  0.559016994374f;
+__constant float fft5_3 = -0.951056516295f;
+__constant float fft5_4 = -1.538841768587f;
+__constant float fft5_5 =  0.363271264002f;
+
+inline float2 mul_float2(float2 a, float2 b){ 
+    float2 res; 
+    res.x = a.x * b.x - a.y * b.y;
+    res.y = a.x * b.y + a.y * b.x;
+    return res; 
+}
+
+inline float2 sincos_float2(float alpha) {
+    float cs, sn;
+    sn = sincos(alpha, &cs);  // sincos
+    return (float2)(cs, sn);
+}
+
+inline float2 twiddle(float2 a) { 
+    return (float2)(a.y, -a.x); 
+}
+
+inline float2 square(float2 a) { 
+    return (float2)(a.x * a.x - a.y * a.y, 2.0f * a.x * a.y); 
+}
+
+inline float2 square3(float2 a) { 
+    return (float2)(a.x * a.x - a.y * a.y, 3.0f * a.x * a.y); 
+}
+
+inline float2 mul_p1q4(float2 a) { 
+    return (float2)(SQRT_2) * (float2)(a.x + a.y, -a.x + a.y); 
+}
+
+inline float2 mul_p3q4(float2 a) { 
+    return (float2)(SQRT_2) * (float2)(-a.x + a.y, -a.x - a.y); 
+}
+
+__attribute__((always_inline))
+void fft_radix2(__local float2* smem, const int x, const int block_size, const int t)       
+{
+    const int k = x & (block_size - 1);
+    float2 in1, temp;
+
+    if (x < t)
+    {
+        in1 = smem[x];
+        float2 in2 = smem[x+t];
+
+        float theta = -PI * k / block_size;
+        float cs;
+        float sn = sincos(theta, &cs);
+        temp = (float2) (in2.x * cs - in2.y * sn,
+                                      in2.y * cs + in2.x * sn);
+    }
+
+    barrier(CLK_LOCAL_MEM_FENCE);
+
+    if (x < t)
+    {
+        const int dst_ind = (x << 1) - k;
+    
+        smem[dst_ind] = in1 + temp;
+        smem[dst_ind+block_size] = in1 - temp;
+    }
+
+    barrier(CLK_LOCAL_MEM_FENCE);
+}
+
+__attribute__((always_inline))
+void fft_radix4(__local float2* smem, const int x, const int block_size, const int t)  
+{
+    const int k = x & (block_size - 1);
+    float2 b0, b1, b2, b3;
+
+    if (x < t)
+    {
+        float theta = -PI * k / (2 * block_size);
+
+        float2 tw = sincos_float2(theta);
+        float2 a0 = smem[x];
+        float2 a1 = mul_float2(tw, smem[x+t]);
+        float2 a2 = smem[x + 2*t];
+        float2 a3 = mul_float2(tw, smem[x + 3*t]);
+        tw = square(tw);
+        a2 = mul_float2(tw, a2);
+        a3 = mul_float2(tw, a3);
+
+        b0 = a0 + a2;
+        b1 = a0 - a2;
+        b2 = a1 + a3;
+        b3 = twiddle(a1 - a3);
+    }
+
+    barrier(CLK_LOCAL_MEM_FENCE);
+
+    if (x < t)
+    {
+        const int dst_ind = ((x - k) << 2) + k;
+        smem[dst_ind] = b0 + b2;
+        smem[dst_ind + block_size] = b1 + b3;
+        smem[dst_ind + 2*block_size] = b0 - b2;
+        smem[dst_ind + 3*block_size] = b1 - b3;
+    }
+
+    barrier(CLK_LOCAL_MEM_FENCE);
+}
+
+__attribute__((always_inline))
+void fft_radix8(__local float2* smem, const int x, const int block_size, const int t)
+{
+    const int k = x % block_size;
+    float2 a0, a1, a2, a3, a4, a5, a6, a7;
+
+    if (x < t)
+    {
+        float theta = -PI * k / (4 * block_size);
+
+        float2 tw = sincos_float2(theta); // W
+        a0 = smem[x];
+        a1 = mul_float2(tw, smem[x + t]);
+        a2 = smem[x + 2 * t];
+        a3 = mul_float2(tw, smem[x + 3 * t]);
+        a4 = smem[x + 4 * t];
+        a5 = mul_float2(tw, smem[x + 5 * t]);
+        a6 = smem[x + 6 * t];
+        a7 = mul_float2(tw, smem[x + 7 * t]);
+
+        tw = square(tw); // W^2
+        a2 = mul_float2(tw, a2);
+        a3 = mul_float2(tw, a3);
+        a6 = mul_float2(tw, a6);
+        a7 = mul_float2(tw, a7);
+        tw = square(tw); // W^4
+        a4 = mul_float2(tw, a4);
+        a5 = mul_float2(tw, a5);
+        a6 = mul_float2(tw, a6);
+        a7 = mul_float2(tw, a7);
+
+        float2 b0 = a0 + a4;
+        float2 b4 = a0 - a4;
+        float2 b1 = a1 + a5; 
+        float2 b5 = mul_p1q4(a1 - a5);
+        float2 b2 = a2 + a6;
+        float2 b6 = twiddle(a2 - a6);
+        float2 b3 = a3 + a7;
+        float2 b7 = mul_p3q4(a3 - a7);
+
+        a0 = b0 + b2;
+        a2 = b0 - b2;
+        a1 = b1 + b3;
+        a3 = twiddle(b1 - b3);
+        a4 = b4 + b6;
+        a6 = b4 - b6;
+        a5 = b5 + b7;
+        a7 = twiddle(b5 - b7);
+    }
+
+    barrier(CLK_LOCAL_MEM_FENCE);
+
+    if (x < t)
+    {
+        const int dst_ind = ((x - k) << 3) + k;
+        __local float2* dst = smem + dst_ind;
+
+        dst[0] = a0 + a1;
+        dst[block_size] = a4 + a5;
+        dst[2 * block_size] = a2 + a3;
+        dst[3 * block_size] = a6 + a7;
+        dst[4 * block_size] = a0 - a1;
+        dst[5 * block_size] = a4 - a5;
+        dst[6 * block_size] = a2 - a3;
+        dst[7 * block_size] = a6 - a7;
+    }
+
+    barrier(CLK_LOCAL_MEM_FENCE);
+}
+
+__attribute__((always_inline))
+void fft_radix3(__local float2* smem, const int x, const int block_size, const int t)
+{
+    const int k = x % block_size;
+    float2 a0, a1, a2, b0, b1;
+
+    if (x < t)
+    {
+        const float theta = -PI * k * 2 / (3 * block_size);
+
+        a0 = smem[x];
+        a1 = mul_float2(sincos_float2(theta), smem[x+t]);
+        a2 = mul_float2(sincos_float2(2 * theta), smem[x+2*t]);
+        b1 = a1 + a2;
+        a2 = twiddle((float2)sin_120*(a1 - a2));
+        b0 = a0 - (float2)(0.5f)*b1;
+    }
+
+    barrier(CLK_LOCAL_MEM_FENCE);
+
+    if (x < t)
+    {
+        const int dst_ind = ((x - k) * 3) + k;
+
+        smem[dst_ind] = a0 + b1;
+        smem[dst_ind + block_size] = b0 + a2;
+        smem[dst_ind + 2*block_size] = b0 - a2;
+    }
+
+    barrier(CLK_LOCAL_MEM_FENCE);
+}
+
+__attribute__((always_inline))
+void fft_radix5(__local float2* smem, const int x, const int block_size, const int t)
+{
+    const int k = x % block_size;
+    float2 a0, a1, a2, a3, a4, b0, b1, b2, b5;
+
+    if (x < t)
+    {
+        const float theta = -PI * k * 2 / (5 * block_size);
+    
+        a0 = smem[x];
+        a1 = mul_float2(sincos_float2(theta), smem[x + t]);
+        a2 = mul_float2(sincos_float2(theta*2),smem[x+2*t]);
+        a3 = mul_float2(sincos_float2(theta*3),smem[x+3*t]);
+        a4 = mul_float2(sincos_float2(theta*4),smem[x+4*t]);
+
+        b1 = a1 + a4;
+        a1 -= a4;
+
+        a4 = a3 + a2;
+        a3 -= a2;
+
+        b2 = b1 + a4;
+        b0 = a0 - (float2)0.25f * b2;
+
+        b1 =  (float2)fft5_2 * (b1 - a4);
+        a4 = -(float2)fft5_3 * (a1 + a3);
+        a4 = twiddle(a4);
+
+        b5 = (float2)(a4.x - fft5_5 * a1.y, a4.y + fft5_5 * a1.x);
+
+        a4.x += fft5_4 * a3.y; 
+        a4.y -= fft5_4 * a3.x;
+
+        a1 = b0 + b1;
+        b0 -= b1;
+    }
+
+    barrier(CLK_LOCAL_MEM_FENCE);
+
+    if (x < t)
+    {
+        const int dst_ind = ((x - k) * 5) + k;
+        __local float2* dst = smem + dst_ind;
+
+        dst[0] = a0 + b2;
+        dst[block_size] = a1 + a4;
+        dst[2 * block_size] = b0 + b5;
+        dst[3 * block_size] = b0 - b5;
+        dst[4 * block_size] = a1 - a4;
+    }
+
+    barrier(CLK_LOCAL_MEM_FENCE);
+}
+
+__kernel void fft_multi_radix(__global const uchar* srcptr, int src_step, int src_offset,
+                              __global uchar* dstptr, int dst_step, int dst_offset,
+                              const int t, const int nz)
+{
+    const int x = get_global_id(0);
+    const int y = get_group_id(1);
+
+    if (y < nz)
+    {
+        __local float2 smem[LOCAL_SIZE];
+        __global const float2* src = (__global const float2*)(srcptr + mad24(y, src_step, mad24(x, (int)(sizeof(float)*2), src_offset)));
+        __global float2* dst = (__global float2*)(dstptr + mad24(y, dst_step, mad24(x, (int)(sizeof(float)*2), dst_offset)));
+
+        const int block_size = LOCAL_SIZE/kercn;
+        #pragma unroll
+        for (int i=0; i<kercn; i++)
+            smem[x+i*block_size] = src[i*block_size];
+
+        barrier(CLK_LOCAL_MEM_FENCE);
+
+        RADIX_PROCESS;
+
+        // copy data to dst
+        #pragma unroll
+        for (int i=0; i<kercn; i++)
+            dst[i*block_size] = smem[x + i*block_size];
+    }
+}

modules/core/test/ocl/test_dft.cpp

@@ -48,16 +48,24 @@
 
 #ifdef HAVE_OPENCL
 
+enum OCL_FFT_TYPE
+{
+    R2R = 0, // real to real (CCS)
+    C2R = 1, // complex to real (CCS)
+    R2C = 2, // real (CCS) to complex
+    C2C = 3  // complex to complex
+};
+
 namespace cvtest {
 namespace ocl {
 
 ////////////////////////////////////////////////////////////////////////////
 // Dft
 
-PARAM_TEST_CASE(Dft, cv::Size, MatDepth, bool, bool, bool, bool)
+PARAM_TEST_CASE(Dft, cv::Size, OCL_FFT_TYPE, bool)
 {
     cv::Size dft_size;
-    int	dft_flags, depth;
+    int	dft_flags, depth, cn, dft_type;
     bool inplace;
 
     TEST_DECLARE_INPUT_PARAMETER(src);
@@ -66,19 +74,31 @@ PARAM_TEST_CASE(Dft, cv::Size, MatDepth, bool, bool, bool, bool)
     virtual void SetUp()
     {
         dft_size = GET_PARAM(0);
-        depth = GET_PARAM(1);
-        inplace = GET_PARAM(2);
+        dft_type = GET_PARAM(1);
+        depth = CV_32F;
 
         dft_flags = 0;
-        if (GET_PARAM(3))
-            dft_flags |= cv::DFT_ROWS;
-        if (GET_PARAM(4))
-            dft_flags |= cv::DFT_SCALE;
-        if (GET_PARAM(5))
-            dft_flags |= cv::DFT_INVERSE;
+        switch (dft_type)
+        {
+        case R2R: dft_flags |= cv::DFT_REAL_OUTPUT; cn = 1; break;
+        case C2R: dft_flags |= cv::DFT_REAL_OUTPUT; cn = 2; break;
+        case R2C: dft_flags |= cv::DFT_COMPLEX_OUTPUT; cn = 1; break;
+        case C2C: dft_flags |= cv::DFT_COMPLEX_OUTPUT; cn = 2; break;
+        }
+
+        inplace = false;
+
+
+        if (GET_PARAM(2))
+            dft_flags |= cv::DFT_ROWS; // (DFT_COMPLEX_OUTPUT | DFT_ROWS) works incorrect
+        //if (GET_PARAM(3))
+        //    if (dft_type == C2C) dft_flags |= cv::DFT_INVERSE;
+        //if (GET_PARAM(3))
+        //    dft_flags |= cv::DFT_SCALE;
+
     }
 
-    void generateTestData(int cn = 2)
+    void generateTestData()
     {
         src = randomMat(dft_size, CV_MAKE_TYPE(depth, cn), 0.0, 100.0);
         usrc = src.getUMat(ACCESS_READ);
@@ -88,12 +108,23 @@ PARAM_TEST_CASE(Dft, cv::Size, MatDepth, bool, bool, bool, bool)
     }
 };
 
-OCL_TEST_P(Dft, C2C)
+OCL_TEST_P(Dft, Mat)
 {
     generateTestData();
 
-    OCL_OFF(cv::dft(src, dst, dft_flags | cv::DFT_COMPLEX_OUTPUT));
-    OCL_ON(cv::dft(usrc, udst, dft_flags | cv::DFT_COMPLEX_OUTPUT));
+    OCL_OFF(cv::dft(src, dst, dft_flags));
+    OCL_ON(cv::dft(usrc, udst, dft_flags));
+    
+    Mat gpu = udst.getMat(ACCESS_READ);
+    std::cout << src << std::endl;
+    std::cout << dst << std::endl;
+    std::cout << gpu << std::endl;
+
+    //int cn = udst.channels();
+    
+    //Mat df;
+    //absdiff(dst, gpu, df);
+    //std::cout <<  df << std::endl;
 
     double eps = src.size().area() * 1e-4;
     EXPECT_MAT_NEAR(dst, udst, eps);
@@ -150,15 +181,13 @@ OCL_TEST_P(MulSpectrums, Mat)
 
 OCL_INSTANTIATE_TEST_CASE_P(OCL_ImgProc, MulSpectrums, testing::Combine(Bool(), Bool()));
 
-OCL_INSTANTIATE_TEST_CASE_P(Core, Dft, Combine(Values(cv::Size(2, 3), cv::Size(5, 4), cv::Size(25, 20),
-                                                       cv::Size(512, 1), cv::Size(1024, 768)),
-                                               Values(CV_32F, CV_64F),
-                                               Bool(), // inplace
-                                               Bool(), // DFT_ROWS
-                                               Bool(), // DFT_SCALE
-                                               Bool()) // DFT_INVERSE
+OCL_INSTANTIATE_TEST_CASE_P(Core, Dft, Combine(Values(cv::Size(2, 3), cv::Size(5, 4), cv::Size(30, 20),
+                                                      cv::Size(512, 1), cv::Size(1024, 1024)),
+                                               Values((OCL_FFT_TYPE) C2C/*, (OCL_FFT_TYPE)  R2R, (OCL_FFT_TYPE)  R2C/*, (OCL_FFT_TYPE) C2R*/),
+                                               Bool() // DFT_ROWS
+                                               )
                             );
 
 } } // namespace cvtest::ocl
 
-#endif // HAVE_OPENCL
+#endif // HAVE_OPENCL

samples/cpp/dft.cpp

@@ -5,6 +5,8 @@
 #include "opencv2/highgui.hpp"
 
 #include <stdio.h>
+#include <iostream>
+#include <chrono>
 
 using namespace cv;
 using namespace std;
@@ -24,6 +26,31 @@ const char* keys =
 
 int main(int argc, const char ** argv)
 {
+    //int cols = 4; 
+    //int rows = 768;
+    //srand(0);
+    //Mat input(Size(cols, rows), CV_32FC2);
+    //for (int i=0; i<cols; i++)
+    //    for (int j=0; j<rows; j++)
+    //        input.at<Vec2f>(j,i) = Vec2f((float) rand() / RAND_MAX, (float) rand() / RAND_MAX);
+    //Mat dst;
+    //
+    //UMat gpu_input, gpu_dst;
+    //input.copyTo(gpu_input);
+    //auto start = std::chrono::system_clock::now();
+    //dft(input, dst, DFT_ROWS);
+    //auto cpu_duration = chrono::duration_cast<chrono::milliseconds>(chrono::system_clock::now() - start);
+    //
+    //start = std::chrono::system_clock::now();
+    //dft(gpu_input, gpu_dst, DFT_ROWS);
+    //auto gpu_duration = chrono::duration_cast<chrono::milliseconds>(chrono::system_clock::now() - start);
+
+    //double n = norm(dst, gpu_dst);
+    //cout << "norm = " << n << endl;
+    //cout << "CPU time: " << cpu_duration.count() << "ms" << endl;
+    //cout << "GPU time: " << gpu_duration.count() << "ms" << endl;
+
+
     help();
     CommandLineParser parser(argc, argv, keys);
     string filename = parser.get<string>(0);
@@ -35,16 +62,46 @@ int main(int argc, const char ** argv)
         printf("Cannot read image file: %s\n", filename.c_str());
         return -1;
     }
-    int M = getOptimalDFTSize( img.rows );
-    int N = getOptimalDFTSize( img.cols );
+
+    Mat small_img = img(Rect(0,0,6,6));
+
+    int M = getOptimalDFTSize( small_img.rows );
+    int N = getOptimalDFTSize( small_img.cols );
     Mat padded;
-    copyMakeBorder(img, padded, 0, M - img.rows, 0, N - img.cols, BORDER_CONSTANT, Scalar::all(0));
+    copyMakeBorder(small_img, padded, 0, M - small_img.rows, 0, N - small_img.cols, BORDER_CONSTANT, Scalar::all(0));
 
-    Mat planes[] = {Mat_<float>(padded), Mat::zeros(padded.size(), CV_32F)};
-    Mat complexImg;
+    Mat planes[] = {Mat_<float>(padded), Mat::ones(padded.size(), CV_32F)};
+    Mat complexImg, complexImg1, complexInput;
     merge(planes, 2, complexImg);
 
-    dft(complexImg, complexImg);
+    Mat realInput;
+    padded.convertTo(realInput, CV_32F);
+    complexInput = complexImg;
+    //cout << complexImg << endl;
+    //dft(complexImg, complexImg, DFT_REAL_OUTPUT);
+    //cout << "Complex to Complex" << endl;
+    //cout << complexImg << endl;
+    cout << "Complex input" << endl << complexInput << endl;
+    cout << "Real input" << endl << realInput << endl;
+
+    dft(complexInput, complexImg1, DFT_COMPLEX_OUTPUT);
+    cout << "Complex to Complex image: " << endl;
+    cout << endl << complexImg1 << endl;
+    
+    Mat realImg1;
+    dft(complexInput, realImg1, DFT_REAL_OUTPUT);
+    cout << "Complex to Real image: " << endl;
+    cout << endl << realImg1 << endl;
+
+    Mat realOut;
+    dft(complexImg1, realOut, DFT_INVERSE | DFT_COMPLEX_OUTPUT);
+    cout << "Complex to Complex (inverse):" << endl;
+    cout << realOut << endl;
+
+    Mat complexOut;
+    dft(realImg1, complexOut, DFT_INVERSE | DFT_REAL_OUTPUT | DFT_SCALE);
+    cout << "Complex to Real (inverse):" << endl;
+    cout << complexOut << endl;
 
     // compute log(1 + sqrt(Re(DFT(img))**2 + Im(DFT(img))**2))
     split(complexImg, planes);