Fix binary compatibility of gpu module

modules/gpu/include/opencv2/gpu/gpu.hpp

@@ -815,6 +815,10 @@ struct CV_EXPORTS CannyBuf
     GpuMat st1, st2;
     GpuMat unused;
     Ptr<FilterEngine_GPU> filterDX, filterDY;
+
+    CannyBuf() {}
+    explicit CannyBuf(const Size& image_size, int apperture_size = 3) {create(image_size, apperture_size);}
+    CannyBuf(const GpuMat& dx_, const GpuMat& dy_);
 };
 
 CV_EXPORTS void Canny(const GpuMat& image, GpuMat& edges, double low_thresh, double high_thresh, int apperture_size = 3, bool L2gradient = false);
@@ -1879,11 +1883,9 @@ private:
     vector<GpuMat> prevPyr_;
     vector<GpuMat> nextPyr_;
     GpuMat vPyr_[2];
-    vector<GpuMat> unused1;
+    vector<GpuMat> buf_;
-    vector<GpuMat> unused2;
+    vector<GpuMat> unused;
-    bool unused3;
+    bool isDeviceArch11_;
-
-    GpuMat buf_;
 };
 
 

modules/gpu/src/imgproc.cpp

@@ -45,6 +45,9 @@
 using namespace cv;
 using namespace cv::gpu;
 
+/*stub for deprecated constructor*/
+cv::gpu::CannyBuf::CannyBuf(const GpuMat&, const GpuMat&) { }
+
 #if !defined (HAVE_CUDA) || defined (CUDA_DISABLER)
 
 void cv::gpu::meanShiftFiltering(const GpuMat&, GpuMat&, int, int, TermCriteria, Stream&) { throw_nogpu(); }

modules/gpu/src/pyrlk.cpp

@@ -147,11 +147,13 @@ void cv::gpu::PyrLKOpticalFlow::sparse(const GpuMat& prevImg, const GpuMat& next
     }
     else
     {
-        cvtColor(prevImg, buf_, COLOR_BGR2BGRA);
+        buf_.resize(1);
-        buf_.convertTo(prevPyr_[0], CV_32F);
 
-        cvtColor(nextImg, buf_, COLOR_BGR2BGRA);
+        cvtColor(prevImg, buf_[0], COLOR_BGR2BGRA);
-        buf_.convertTo(nextPyr_[0], CV_32F);
+        buf_[0].convertTo(prevPyr_[0], CV_32F);
+
+        cvtColor(nextImg, buf_[0], COLOR_BGR2BGRA);
+        buf_[0].convertTo(nextPyr_[0], CV_32F);
     }
 
     for (int level = 1; level <= maxLevel; ++level)
@@ -237,7 +239,7 @@ void cv::gpu::PyrLKOpticalFlow::releaseMemory()
     prevPyr_.clear();
     nextPyr_.clear();
 
-    buf_.release();
+    buf_.clear();
 
     uPyr_[0].release();
     vPyr_[0].release();