Fix ocl::filter2D.

In current implementation, this function only works when anchor point is
in the kernel center and kernel size supported is either 3x3 or 5x5.

modules/ocl/include/opencv2/ocl/ocl.hpp

@@ -689,6 +689,8 @@ namespace cv
         }
 
         //! applies non-separable 2D linear filter to the image
+        //  Note, at the moment this function only works when anchor point is in the kernel center
+        //  and kernel size supported is either 3x3 or 5x5; otherwise the function will fail to output valid result
         CV_EXPORTS void filter2D(const oclMat &src, oclMat &dst, int ddepth, const Mat &kernel,
                                  Point anchor = Point(-1, -1), int borderType = BORDER_DEFAULT);
 

modules/ocl/src/filtering.cpp

@@ -645,7 +645,11 @@ static void GPUFilter2D(const oclMat &src, oclMat &dst, oclMat &mat_kernel,
     args.push_back(make_pair(sizeof(cl_int), (void *)&src.wholecols));
     args.push_back(make_pair(sizeof(cl_int), (void *)&src.wholerows));
 
-    openCLExecuteKernel(clCxt, &filtering_laplacian, kernelName, globalThreads, localThreads, args, cn, depth);
+    const int buffer_size = 100;
+    char opt_buffer [buffer_size] = "";
+    sprintf(opt_buffer, "-DANCHOR=%d -DANX=%d -DANY=%d", ksize.width, anchor.x, anchor.y);
+
+    openCLExecuteKernel(clCxt, &filtering_laplacian, kernelName, globalThreads, localThreads, args, cn, depth, opt_buffer);
 }
 Ptr<BaseFilter_GPU> cv::ocl::getLinearFilter_GPU(int srcType, int dstType, const Mat &kernel, const Size &ksize,
         Point anchor, int borderType)
@@ -656,7 +660,7 @@ Ptr<BaseFilter_GPU> cv::ocl::getLinearFilter_GPU(int srcType, int dstType, const
 
     oclMat gpu_krnl;
     int nDivisor;
-    normalizeKernel(kernel, gpu_krnl, CV_32S, &nDivisor, true);
+    normalizeKernel(kernel, gpu_krnl, CV_32S, &nDivisor, false);
     normalizeAnchor(anchor, ksize);
 
     return Ptr<BaseFilter_GPU>(new LinearFilter_GPU(ksize, anchor, gpu_krnl, GPUFilter2D_callers[CV_MAT_CN(srcType)],
@@ -1172,7 +1176,7 @@ void linearRowFilter_gpu(const oclMat &src, const oclMat &dst, oclMat mat_kernel
     args.push_back(make_pair(sizeof(cl_int), (void *)&ridusy));
     args.push_back(make_pair(sizeof(cl_mem), (void *)&mat_kernel.data));
 
-    openCLExecuteKernel2(clCxt, &filter_sep_row, kernelName, globalThreads, localThreads, args, channels, src.depth(), compile_option, CLFLUSH);
+    openCLExecuteKernel(clCxt, &filter_sep_row, kernelName, globalThreads, localThreads, args, channels, src.depth(), compile_option);
 }
 
 Ptr<BaseRowFilter_GPU> cv::ocl::getLinearRowFilter_GPU(int srcType, int /*bufType*/, const Mat &rowKernel, int anchor, int bordertype)

modules/ocl/src/opencl/filtering_laplacian.cl

@@ -82,9 +82,9 @@
 //////////////////////////////////////////////////////////////////////////////////////////////////////
 /////////////////////////////Macro for define elements number per thread/////////////////////////////
 ////////////////////////////////////////////////////////////////////////////////////////////////////
-#define ANCHOR                  3
-#define ANX                     1
-#define ANY                     1
+//#define ANCHOR                  3
+//#define ANX                     1
+//#define ANY                     1
 
 #define ROWS_PER_GROUP          4
 #define ROWS_PER_GROUP_BITS     2
@@ -185,7 +185,7 @@ __kernel void filter2D_C1_D0(__global uchar *src, int src_step, int src_offset_x
 
         for(int i = 0; i < ANCHOR; i++)
         {
-#pragma unroll 3
+#pragma unroll
             for(int j = 0; j < ANCHOR; j++)
             {
                 if(dst_rows_index < dst_rows_end)
@@ -295,7 +295,7 @@ __kernel void filter2D_C1_D5(__global float *src, int src_step, int src_offset_x
 
         for(int i = 0; i < ANCHOR; i++)
         {
-#pragma unroll 3
+#pragma unroll
             for(int j = 0; j < ANCHOR; j++)
             {
                 if(dst_rows_index < dst_rows_end)
@@ -410,7 +410,7 @@ __kernel void filter2D_C4_D0(__global uchar4 *src, int src_step, int src_offset_
 
         for(int i = 0; i < ANCHOR; i++)
         {
-#pragma unroll 3
+#pragma unroll
             for(int j = 0; j < ANCHOR; j++)
             {
                 if(dst_rows_index < dst_rows_end)