diff --git a/modules/gpu/src/cuda/cuda_shared.hpp b/modules/gpu/src/cuda/cuda_shared.hpp
index 272e4f56cd..d0fba59641 100644
--- a/modules/gpu/src/cuda/cuda_shared.hpp
+++ b/modules/gpu/src/cuda/cuda_shared.hpp
@@ -59,7 +59,6 @@ namespace cv
         namespace impl
         {
             static inline int divUp(int a, int b) { return (a % b == 0) ? a/b : a/b + 1; }
-           
 
             extern "C" void set_to_without_mask (const DevMem2D& mat, const double * scalar, int depth, int channels);
             extern "C" void set_to_with_mask    (const DevMem2D& mat, const double * scalar, const DevMem2D& mask, int depth, int channels);
diff --git a/modules/gpu/src/cuda/matrix_operations.cu b/modules/gpu/src/cuda/matrix_operations.cu
index 533c780c04..ce5c6cd2f2 100644
--- a/modules/gpu/src/cuda/matrix_operations.cu
+++ b/modules/gpu/src/cuda/matrix_operations.cu
@@ -50,97 +50,32 @@ __constant__ __align__(16) float scalar_d[4];
 
 namespace mat_operators
 {
-    template <typename T, int channels, int count = channels>
-    struct unroll
-    {
-        __device__ static void unroll_set(T * mat, size_t i)
-        {
-            mat[i] = static_cast<T>(scalar_d[channels - count]);
-            unroll<T, channels, count - 1>::unroll_set(mat, i+1);
-        }
-
-        __device__ static void unroll_set_with_mask(T * mat, unsigned char mask, size_t i)
-        {
-            if ( mask != 0 )
-                mat[i] = static_cast<T>(scalar_d[channels - count]);
-
-            unroll<T, channels, count - 1>::unroll_set_with_mask(mat, mask, i+1);
-        }
-    };
-
-    template <typename T, int channels>
-    struct unroll<T, channels, 0>
-    {
-        __device__ static void unroll_set(T * , size_t){}
-        __device__ static void unroll_set_with_mask(T * , unsigned char, size_t){}
-    };
-
-    template <typename T, int channels>
-    __device__ size_t GetIndex(size_t i, int cols, int step)
-    {
-        size_t ret =    (i / static_cast<size_t>(cols))*static_cast<size_t>(step) / static_cast<size_t>(sizeof(T)) +
-                        (i % static_cast<size_t>(cols))*static_cast<size_t>(channels);
-        return  ret;
-    }
-
-    template <typename T, int channels>
+    template<typename T, int channels>
     __global__ void kernel_set_to_without_mask(T * mat, int cols, int rows, int step)
     {
-        size_t i = (blockIdx.x * blockDim.x + threadIdx.x);
+        size_t x = blockIdx.x * blockDim.x + threadIdx.x;
+        size_t y = blockIdx.y * blockDim.y + threadIdx.y;
 
-        if (i < cols * rows)
+        if ((x < cols * channels ) && (y < rows))
         {
-            unroll<T, channels>::unroll_set(mat, GetIndex<T,channels>(i, cols, step));
+            size_t idx = y * (step / sizeof(T)) + x;
+            mat[idx] = scalar_d[ x % channels ];
         }
     }
 
-    template <typename T, int channels>
-    __global__ void kernel_set_to_with_mask(T * mat, const unsigned char * mask, int cols, int rows, int step)
+    template<typename T, int channels>
+    __global__ void kernel_set_to_with_mask(T * mat, const unsigned char * mask, int cols, int rows, int step, int step_mask)
     {
-        size_t i = (blockIdx.x * blockDim.x + threadIdx.x);
-        if (i < cols * rows)
-            unroll<T, channels>::unroll_set_with_mask(mat, mask[i], GetIndex<T,channels>(i, cols, step));
-    }
-}
+        size_t x = blockIdx.x * blockDim.x + threadIdx.x;
+        size_t y = blockIdx.y * blockDim.y + threadIdx.y;
 
-extern "C" void cv::gpu::impl::set_to_with_mask(const DevMem2D& mat, const double * scalar, const DevMem2D& mask, int elemSize1, int channels)
-{
-    // download scalar to constant memory
-    float data[4];
-    data[0] = static_cast<float>(scalar[0]);
-    data[1] = static_cast<float>(scalar[1]);
-    data[2] = static_cast<float>(scalar[2]);
-    data[3] = static_cast<float>(scalar[3]);
-    cudaSafeCall( cudaMemcpyToSymbol(scalar_d, &data, sizeof(data)));
-
-    dim3 threadsPerBlock(256,1,1);
-    dim3 numBlocks (mat.rows * mat.cols / threadsPerBlock.x + 1, 1, 1);
-
-    if (channels == 1)
-    {
-        if (elemSize1 == 1) ::mat_operators::kernel_set_to_with_mask<unsigned char,  1><<<numBlocks,threadsPerBlock>>>(mat.ptr, (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step);
-        if (elemSize1 == 2) ::mat_operators::kernel_set_to_with_mask<unsigned short, 1><<<numBlocks,threadsPerBlock>>>((unsigned short *)mat.ptr, (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step);
-        if (elemSize1 == 4) ::mat_operators::kernel_set_to_with_mask<float ,   1><<<numBlocks,threadsPerBlock>>>((float  *)mat.ptr, (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step);
+        if (mask[y * step_mask + x] != 0)
+            if ((x < cols * channels ) && (y < rows))
+            {
+                size_t idx = y * (step / sizeof(T)) + x;
+                mat[idx] = scalar_d[ x % channels ];
+            }
     }
-    if (channels == 2)
-    {
-        if (elemSize1 == 1) ::mat_operators::kernel_set_to_with_mask<unsigned char,  2><<<numBlocks,threadsPerBlock>>>(mat.ptr, (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step);
-        if (elemSize1 == 2) ::mat_operators::kernel_set_to_with_mask<unsigned short, 2><<<numBlocks,threadsPerBlock>>>((unsigned short *)mat.ptr, (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step);
-        if (elemSize1 == 4) ::mat_operators::kernel_set_to_with_mask<float ,   2><<<numBlocks,threadsPerBlock>>>((float  *)mat.ptr, (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step);
-    }
-    if (channels == 3)
-    {
-        if (elemSize1 == 1) ::mat_operators::kernel_set_to_with_mask<unsigned char,  3><<<numBlocks,threadsPerBlock>>>(mat.ptr, (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step);
-        if (elemSize1 == 2) ::mat_operators::kernel_set_to_with_mask<unsigned short, 3><<<numBlocks,threadsPerBlock>>>((unsigned short *)mat.ptr, (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step);
-        if (elemSize1 == 4) ::mat_operators::kernel_set_to_with_mask<float ,   3><<<numBlocks,threadsPerBlock>>>((float  *)mat.ptr, (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step);
-    }
-    if (channels == 4)
-    {
-        if (elemSize1 == 1) ::mat_operators::kernel_set_to_with_mask<unsigned char,  4><<<numBlocks,threadsPerBlock>>>(mat.ptr, (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step);
-        if (elemSize1 == 2) ::mat_operators::kernel_set_to_with_mask<unsigned short, 4><<<numBlocks,threadsPerBlock>>>((unsigned short *)mat.ptr, (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step);
-        if (elemSize1 == 4) ::mat_operators::kernel_set_to_with_mask<float ,   4><<<numBlocks,threadsPerBlock>>>((float  *)mat.ptr, (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step);
-    }
-    cudaSafeCall( cudaThreadSynchronize() );
 }
 
 extern "C" void cv::gpu::impl::set_to_without_mask(const DevMem2D& mat, const double * scalar, int elemSize1, int channels)
@@ -152,33 +87,74 @@ extern "C" void cv::gpu::impl::set_to_without_mask(const DevMem2D& mat, const do
     data[3] = static_cast<float>(scalar[3]);
     cudaSafeCall( cudaMemcpyToSymbol(scalar_d, &data, sizeof(data)));
 
-    dim3 threadsPerBlock(256, 1, 1);
-    dim3 numBlocks (mat.rows * mat.cols / threadsPerBlock.x + 1, 1, 1);
+    dim3 threadsPerBlock(16, 16, 1);
+    dim3 numBlocks (mat.cols * channels / threadsPerBlock.x + 1, mat.rows / threadsPerBlock.y + 1, 1);
 
     if (channels == 1)
     {
         if (elemSize1 == 1) ::mat_operators::kernel_set_to_without_mask<unsigned char,  1><<<numBlocks,threadsPerBlock>>>(mat.ptr, mat.cols, mat.rows, mat.step);
         if (elemSize1 == 2) ::mat_operators::kernel_set_to_without_mask<unsigned short, 1><<<numBlocks,threadsPerBlock>>>((unsigned short *)mat.ptr, mat.cols, mat.rows, mat.step);
-        if (elemSize1 == 4) ::mat_operators::kernel_set_to_without_mask< float,   1><<<numBlocks,threadsPerBlock>>>(( float *)mat.ptr, mat.cols, mat.rows, mat.step);
+        if (elemSize1 == 4) ::mat_operators::kernel_set_to_without_mask<float,          1><<<numBlocks,threadsPerBlock>>>((float *)mat.ptr, mat.cols, mat.rows, mat.step);
     }
     if (channels == 2)
     {
         if (elemSize1 == 1) ::mat_operators::kernel_set_to_without_mask<unsigned char,  2><<<numBlocks,threadsPerBlock>>>(mat.ptr, mat.cols, mat.rows, mat.step);
         if (elemSize1 == 2) ::mat_operators::kernel_set_to_without_mask<unsigned short, 2><<<numBlocks,threadsPerBlock>>>((unsigned short *)mat.ptr, mat.cols, mat.rows, mat.step);
-        if (elemSize1 == 4) ::mat_operators::kernel_set_to_without_mask< float ,   2><<<numBlocks,threadsPerBlock>>>((float *)mat.ptr, mat.cols, mat.rows, mat.step);
+        if (elemSize1 == 4) ::mat_operators::kernel_set_to_without_mask<float,          2><<<numBlocks,threadsPerBlock>>>((float *)mat.ptr, mat.cols, mat.rows, mat.step);
     }
     if (channels == 3)
     {
         if (elemSize1 == 1) ::mat_operators::kernel_set_to_without_mask<unsigned char,  3><<<numBlocks,threadsPerBlock>>>(mat.ptr, mat.cols, mat.rows, mat.step);
         if (elemSize1 == 2) ::mat_operators::kernel_set_to_without_mask<unsigned short, 3><<<numBlocks,threadsPerBlock>>>((unsigned short *)mat.ptr, mat.cols, mat.rows, mat.step);
-        if (elemSize1 == 4) ::mat_operators::kernel_set_to_without_mask< float,   3><<<numBlocks,threadsPerBlock>>>(( float *)mat.ptr, mat.cols, mat.rows, mat.step);
+        if (elemSize1 == 4) ::mat_operators::kernel_set_to_without_mask<float,          3><<<numBlocks,threadsPerBlock>>>((float *)mat.ptr, mat.cols, mat.rows, mat.step);
     }
     if (channels == 4)
     {
         if (elemSize1 == 1) ::mat_operators::kernel_set_to_without_mask<unsigned char,  4><<<numBlocks,threadsPerBlock>>>(mat.ptr, mat.cols, mat.rows, mat.step);
         if (elemSize1 == 2) ::mat_operators::kernel_set_to_without_mask<unsigned short, 4><<<numBlocks,threadsPerBlock>>>((unsigned short *)mat.ptr, mat.cols, mat.rows, mat.step);
-        if (elemSize1 == 4) ::mat_operators::kernel_set_to_without_mask<float,   4><<<numBlocks,threadsPerBlock>>>((float *)mat.ptr, mat.cols, mat.rows, mat.step);
+        if (elemSize1 == 4) ::mat_operators::kernel_set_to_without_mask<float,          4><<<numBlocks,threadsPerBlock>>>((float *)mat.ptr, mat.cols, mat.rows, mat.step);
     }
 
-    cudaSafeCall( cudaThreadSynchronize() );
+    cudaSafeCall ( cudaThreadSynchronize() );
 }
+
+extern "C" void cv::gpu::impl::set_to_with_mask(const DevMem2D& mat, const double * scalar, const DevMem2D& mask, int elemSize1, int channels)
+{
+    float data[4];
+    data[0] = static_cast<float>(scalar[0]);
+    data[1] = static_cast<float>(scalar[1]);
+    data[2] = static_cast<float>(scalar[2]);
+    data[3] = static_cast<float>(scalar[3]);
+    cudaSafeCall( cudaMemcpyToSymbol(scalar_d, &data, sizeof(data)));
+
+    dim3 threadsPerBlock(16, 16, 1);
+    dim3 numBlocks (mat.cols * channels / threadsPerBlock.x + 1, mat.rows / threadsPerBlock.y + 1, 1);
+
+    if (channels == 1)
+    {
+        if (elemSize1 == 1) ::mat_operators::kernel_set_to_with_mask<unsigned char,  1><<<numBlocks,threadsPerBlock>>>(mat.ptr,                   (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step, mask.step);
+        if (elemSize1 == 2) ::mat_operators::kernel_set_to_with_mask<unsigned short, 1><<<numBlocks,threadsPerBlock>>>((unsigned short *)mat.ptr, (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step, mask.step);
+        if (elemSize1 == 4) ::mat_operators::kernel_set_to_with_mask<float,          1><<<numBlocks,threadsPerBlock>>>((float *)mat.ptr,          (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step, mask.step);
+    }
+    if (channels == 2)
+    {
+        if (elemSize1 == 1) ::mat_operators::kernel_set_to_with_mask<unsigned char,  2><<<numBlocks,threadsPerBlock>>>(mat.ptr,                   (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step, mask.step);
+        if (elemSize1 == 2) ::mat_operators::kernel_set_to_with_mask<unsigned short, 2><<<numBlocks,threadsPerBlock>>>((unsigned short *)mat.ptr, (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step, mask.step);
+        if (elemSize1 == 4) ::mat_operators::kernel_set_to_with_mask<float,          2><<<numBlocks,threadsPerBlock>>>((float *)mat.ptr,          (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step, mask.step);
+    }
+    if (channels == 3)
+    {
+        if (elemSize1 == 1) ::mat_operators::kernel_set_to_with_mask<unsigned char,  3><<<numBlocks,threadsPerBlock>>>(mat.ptr,                   (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step, mask.step);
+        if (elemSize1 == 2) ::mat_operators::kernel_set_to_with_mask<unsigned short, 3><<<numBlocks,threadsPerBlock>>>((unsigned short *)mat.ptr, (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step, mask.step);
+        if (elemSize1 == 4) ::mat_operators::kernel_set_to_with_mask<float,          3><<<numBlocks,threadsPerBlock>>>((float *)mat.ptr,          (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step, mask.step);
+    }
+    if (channels == 4)
+    {
+        if (elemSize1 == 1) ::mat_operators::kernel_set_to_with_mask<unsigned char,  4><<<numBlocks,threadsPerBlock>>>(mat.ptr,                   (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step, mask.step);
+        if (elemSize1 == 2) ::mat_operators::kernel_set_to_with_mask<unsigned short, 4><<<numBlocks,threadsPerBlock>>>((unsigned short *)mat.ptr, (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step, mask.step);
+        if (elemSize1 == 4) ::mat_operators::kernel_set_to_with_mask<float,          4><<<numBlocks,threadsPerBlock>>>((float *)mat.ptr,          (unsigned char *)mask.ptr, mat.cols, mat.rows, mat.step, mask.step);
+    }
+
+    cudaSafeCall ( cudaThreadSynchronize() );
+}
+
diff --git a/tests/gpu/src/operator_set_to.cpp b/tests/gpu/src/operator_set_to.cpp
index f5b985d6ca..d071004a3c 100644
--- a/tests/gpu/src/operator_set_to.cpp
+++ b/tests/gpu/src/operator_set_to.cpp
@@ -6,6 +6,7 @@
 #include <iterator>
 #include <limits>
 #include <numeric>
+#include <iomanip> // for  cout << setw()
 
 using namespace cv;
 using namespace std;
@@ -35,6 +36,7 @@ class CV_GpuMatOpSetTo : public CvTest
         bool test_cv_32f_c3();
         bool test_cv_32f_c4();
 
+
     private:
         int rows;
         int cols;
@@ -43,8 +45,8 @@ class CV_GpuMatOpSetTo : public CvTest
 
 CV_GpuMatOpSetTo::CV_GpuMatOpSetTo(): CvTest( "GpuMatOperatorSetTo", "setTo" )
 {
-    rows = 127;
-    cols = 129;
+    rows = 129;
+    cols = 127;
 
     s.val[0] = 128.0;
     s.val[1] = 128.0;
@@ -75,8 +77,9 @@ bool CV_GpuMatOpSetTo::compare_matrix(cv::Mat & cpumat, gpu::GpuMat & gpumat)
     //int64 time1 = getTickCount();
     gpumat.setTo(s);
     //int64 time2 = getTickCount();
-    //std::cout << "\ntime cpu:" << double((time1 - time) / getTickFrequency());
-    //std::cout << "\ntime gpu:" << double((time2 - time1) / getTickFrequency());
+
+    //std::cout << "\ntime cpu: " << std::fixed << std::setprecision(12) << double((time1 - time)  / (double)getTickFrequency());
+    //std::cout << "\ntime gpu: " << std::fixed << std::setprecision(12) << double((time2 - time1) / (double)getTickFrequency());
     //std::cout << "\n";
 
 #ifdef PRINT_MATRIX