Merge remote-tracking branch 'origin/master'

modules/core/include/opencv2/core/gpumat.hpp

@@ -112,6 +112,8 @@ namespace cv { namespace gpu
 
         int multiProcessorCount() const { return multi_processor_count_; }
 
+        size_t sharedMemPerBlock() const { return sharedMemPerBlock_; }
+
         size_t freeMemory() const;
         size_t totalMemory() const;
 
@@ -133,6 +135,7 @@ namespace cv { namespace gpu
         int multi_processor_count_;
         int majorVersion_;
         int minorVersion_;
+        size_t sharedMemPerBlock_;
     };
 
     CV_EXPORTS void printCudaDeviceInfo(int device);

modules/core/src/gpumat.cpp

@@ -42,7 +42,6 @@
 
 #include "precomp.hpp"
 #include "opencv2/core/gpumat.hpp"
-
 #include <iostream>
 
 #ifdef HAVE_CUDA
@@ -301,6 +300,7 @@ void cv::gpu::DeviceInfo::query()
     multi_processor_count_ = prop.multiProcessorCount;
     majorVersion_ = prop.major;
     minorVersion_ = prop.minor;
+    sharedMemPerBlock_ = prop.sharedMemPerBlock;
 }
 
 void cv::gpu::DeviceInfo::queryMemory(size_t& free_memory, size_t& total_memory) const

modules/features2d/src/matchers.cpp

@@ -426,10 +426,10 @@ void BFMatcher::radiusMatchImpl( const Mat& queryDescriptors, vector<vector<DMat
 
         for( int qIdx = 0; qIdx < queryDescriptors.rows; qIdx++ )
         {
-            const float* distptr = dist.ptr<float>(qIdx);
+            const float* distptr = distf.ptr<float>(qIdx);
 
             vector<DMatch>& mq = matches[qIdx];
-            for( int k = 0; k < dist.cols; k++ )
+            for( int k = 0; k < distf.cols; k++ )
             {
                 if( distptr[k] <= maxDistance )
                     mq.push_back( DMatch(qIdx, k, iIdx, distptr[k]) );

modules/gpu/doc/image_processing.rst

@@ -885,3 +885,94 @@ Finds edges in an image using the [Canny86]_ algorithm.
 
 .. seealso:: :ocv:func:`Canny`
 
+
+
+gpu::HoughLines
+---------------
+Finds lines in a binary image using the classical Hough transform.
+
+.. ocv:function:: void gpu::HoughLines(const GpuMat& src, GpuMat& lines, float rho, float theta, int threshold, bool doSort = false, int maxLines = 4096)
+
+.. ocv:function:: void gpu::HoughLines(const GpuMat& src, GpuMat& lines, GpuMat& accum, GpuMat& buf, float rho, float theta, int threshold, bool doSort = false, int maxLines = 4096)
+
+    :param src: 8-bit, single-channel binary source image.
+
+    :param lines: Output vector of lines. Each line is represented by a two-element vector  :math:`(\rho, \theta)` .  :math:`\rho`  is the distance from the coordinate origin  :math:`(0,0)`  (top-left corner of the image).  :math:`\theta`  is the line rotation angle in radians ( :math:`0 \sim \textrm{vertical line}, \pi/2 \sim \textrm{horizontal line}` ).
+
+    :param rho: Distance resolution of the accumulator in pixels.
+
+    :param theta: Angle resolution of the accumulator in radians.
+
+    :param threshold: Accumulator threshold parameter. Only those lines are returned that get enough votes ( :math:`>\texttt{threshold}` ).
+
+    :param doSort: Performs lines sort by votes.
+
+    :param maxLines: Maximum number of output lines.
+
+    :param accum: Optional buffer for accumulator to avoid extra memory allocations (for many calls with the same sizes).
+
+    :param buf: Optional buffer to avoid extra memory allocations (for many calls with the same sizes).
+
+.. seealso:: :ocv:func:`HoughLines`
+
+
+
+gpu::HoughLinesTransform
+------------------------
+Performs classical Hough transform for line detection.
+
+.. ocv:function:: void gpu::HoughLinesTransform(const GpuMat& src, GpuMat& accum, GpuMat& buf, float rho, float theta)
+
+    :param src: 8-bit, single-channel binary source image.
+
+    :param accum: Output accumulator array.
+
+    :param buf: Buffer to avoid extra memory allocations (for many calls with the same sizes).
+
+    :param rho: Distance resolution of the accumulator in pixels.
+
+    :param theta: Angle resolution of the accumulator in radians.
+
+    :param threshold: Accumulator threshold parameter. Only those lines are returned that get enough votes ( :math:`>\texttt{threshold}` ).
+
+.. seealso:: :ocv:func:`gpu::HoughLines`
+
+
+
+gpu::HoughLinesGet
+------------------
+Finds lines in Hough space.
+
+.. ocv:function:: void gpu::HoughLinesGet(const GpuMat& accum, GpuMat& lines, float rho, float theta, int threshold, bool doSort = false, int maxLines = 4096)
+
+    :param accum: Accumulator array.
+
+    :param lines: Output vector of lines. Each line is represented by a two-element vector  :math:`(\rho, \theta)` .  :math:`\rho`  is the distance from the coordinate origin  :math:`(0,0)`  (top-left corner of the image).  :math:`\theta`  is the line rotation angle in radians ( :math:`0 \sim \textrm{vertical line}, \pi/2 \sim \textrm{horizontal line}` ).
+
+    :param rho: Distance resolution of the accumulator in pixels.
+
+    :param theta: Angle resolution of the accumulator in radians.
+
+    :param threshold: Accumulator threshold parameter. Only those lines are returned that get enough votes ( :math:`>\texttt{threshold}` ).
+
+    :param doSort: Performs lines sort by votes.
+
+    :param maxLines: Maximum number of output lines.
+
+.. seealso:: :ocv:func:`gpu::HoughLines`
+
+
+
+gpu::HoughLinesDownload
+-----------------------
+Downloads results from :ocv:func:`gpu::HoughLines` to host memory.
+
+.. ocv:function:: void gpu::HoughLinesDownload(const GpuMat& d_lines, OutputArray h_lines, OutputArray h_votes = noArray())
+
+    :param d_lines: Result of :ocv:func:`gpu::HoughLines` .
+
+    :param h_lines: Output host array.
+
+    :param h_votes: Optional output array for line's votes.
+
+.. seealso:: :ocv:func:`gpu::HoughLines`

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

@@ -820,6 +820,12 @@ private:
     int nLayers_;
 };
 
+CV_EXPORTS void HoughLines(const GpuMat& src, GpuMat& lines, float rho, float theta, int threshold, bool doSort = false, int maxLines = 4096);
+CV_EXPORTS void HoughLines(const GpuMat& src, GpuMat& lines, GpuMat& accum, GpuMat& buf, float rho, float theta, int threshold, bool doSort = false, int maxLines = 4096);
+CV_EXPORTS void HoughLinesTransform(const GpuMat& src, GpuMat& accum, GpuMat& buf, float rho, float theta);
+CV_EXPORTS void HoughLinesGet(const GpuMat& accum, GpuMat& lines, float rho, float theta, int threshold, bool doSort = false, int maxLines = 4096);
+CV_EXPORTS void HoughLinesDownload(const GpuMat& d_lines, OutputArray h_lines, OutputArray h_votes = noArray());
+
 ////////////////////////////// Matrix reductions //////////////////////////////
 
 //! computes mean value and standard deviation of all or selected array elements

modules/gpu/perf/perf_imgproc.cpp

@@ -1331,4 +1331,51 @@ INSTANTIATE_TEST_CASE_P(ImgProc, ImagePyramid_getLayer, testing::Combine(
                     MatType(CV_16UC1), MatType(CV_16UC3), MatType(CV_16UC4),
                     MatType(CV_32FC1), MatType(CV_32FC3), MatType(CV_32FC4))));
 
+//////////////////////////////////////////////////////////////////////
+// HoughLines
+
+IMPLEMENT_PARAM_CLASS(DoSort, bool)
+
+GPU_PERF_TEST(HoughLines, cv::gpu::DeviceInfo, cv::Size, DoSort)
+{
+    declare.time(30.0);
+
+    const cv::gpu::DeviceInfo devInfo = GET_PARAM(0);
+    cv::gpu::setDevice(devInfo.deviceID());
+    const cv::Size size = GET_PARAM(1);
+    const bool doSort = GET_PARAM(2);
+
+    const float rho = 1.0f;
+    const float theta = CV_PI / 180.0f;
+    const int threshold = 300;
+
+    cv::RNG rng(123456789);
+
+    cv::Mat src(size, CV_8UC1, cv::Scalar::all(0));
+
+    const int numLines = rng.uniform(500, 2000);
+    for (int i = 0; i < numLines; ++i)
+    {
+        cv::Point p1(rng.uniform(0, src.cols), rng.uniform(0, src.rows));
+        cv::Point p2(rng.uniform(0, src.cols), rng.uniform(0, src.rows));
+        cv::line(src, p1, p2, cv::Scalar::all(255), 2);
+    }
+
+    cv::gpu::GpuMat d_src(src);
+    cv::gpu::GpuMat d_lines;
+    cv::gpu::GpuMat d_accum;
+    cv::gpu::GpuMat d_buf;
+    cv::gpu::HoughLines(d_src, d_lines, d_accum, d_buf, rho, theta, threshold, doSort);
+
+    TEST_CYCLE()
+    {
+        cv::gpu::HoughLines(d_src, d_lines, d_accum, d_buf, rho, theta, threshold, doSort);
+    }
+}
+
+INSTANTIATE_TEST_CASE_P(ImgProc, HoughLines, testing::Combine(
+    ALL_DEVICES,
+    GPU_TYPICAL_MAT_SIZES,
+    testing::Values(DoSort(false), DoSort(true))));
+
 #endif

modules/gpu/perf_cpu/perf_imgproc.cpp

@@ -727,4 +727,45 @@ INSTANTIATE_TEST_CASE_P(ImgProc, CvtColor, testing::Combine(
                     CvtColorInfo(1, 3, cv::COLOR_BayerGR2BGR),
                     CvtColorInfo(4, 4, cv::COLOR_RGBA2mRGBA))));
 
+//////////////////////////////////////////////////////////////////////
+// HoughLines
+
+IMPLEMENT_PARAM_CLASS(DoSort, bool)
+
+GPU_PERF_TEST(HoughLines, cv::gpu::DeviceInfo, cv::Size, DoSort)
+{
+    declare.time(30.0);
+
+    const cv::Size size = GET_PARAM(1);
+
+    const float rho = 1.0f;
+    const float theta = CV_PI / 180.0f;
+    const int threshold = 300;
+
+    cv::RNG rng(123456789);
+
+    cv::Mat src(size, CV_8UC1, cv::Scalar::all(0));
+
+    const int numLines = rng.uniform(500, 2000);
+    for (int i = 0; i < numLines; ++i)
+    {
+        cv::Point p1(rng.uniform(0, src.cols), rng.uniform(0, src.rows));
+        cv::Point p2(rng.uniform(0, src.cols), rng.uniform(0, src.rows));
+        cv::line(src, p1, p2, cv::Scalar::all(255), 2);
+    }
+
+    std::vector<cv::Vec2f> lines;
+    cv::HoughLines(src, lines, rho, theta, threshold);
+
+    TEST_CYCLE()
+    {
+        cv::HoughLines(src, lines, rho, theta, threshold);
+    }
+}
+
+INSTANTIATE_TEST_CASE_P(ImgProc, HoughLines, testing::Combine(
+    ALL_DEVICES,
+    GPU_TYPICAL_MAT_SIZES,
+    testing::Values(DoSort(false), DoSort(true))));
+
 #endif

modules/gpu/src/cuda/hough.cu

@@ -0,0 +1,295 @@
+/*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) 2000-2008, Intel Corporation, all rights reserved.
+// Copyright (C) 2009, Willow Garage 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 bpied warranties, including, but not limited to, the bpied
+// 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 <thrust/sort.h>
+#include "opencv2/gpu/device/common.hpp"
+#include "opencv2/gpu/device/emulation.hpp"
+
+namespace cv { namespace gpu { namespace device
+{
+    namespace hough
+    {
+        __device__ int g_counter;
+
+        ////////////////////////////////////////////////////////////////////////
+        // buildPointList
+
+        const int PIXELS_PER_THREAD = 16;
+
+        __global__ void buildPointList(const DevMem2Db src, unsigned int* list)
+        {
+            __shared__ int s_queues[4][32 * PIXELS_PER_THREAD];
+            __shared__ int s_qsize[4];
+            __shared__ int s_start[4];
+
+            const int x = blockIdx.x * blockDim.x * PIXELS_PER_THREAD + threadIdx.x;
+            const int y = blockIdx.y * blockDim.y + threadIdx.y;
+
+            if (y >= src.rows)
+                return;
+
+            if (threadIdx.x == 0)
+                s_qsize[threadIdx.y] = 0;
+
+            __syncthreads();
+
+            // fill the queue
+            for (int i = 0, xx = x; i < PIXELS_PER_THREAD && xx < src.cols; ++i, xx += blockDim.x)
+            {
+                if (src(y, xx))
+                {
+                    const unsigned int val = (y << 16) | xx;
+                    const int qidx = Emulation::smem::atomicAdd(&s_qsize[threadIdx.y], 1);
+                    s_queues[threadIdx.y][qidx] = val;
+                }
+            }
+
+            __syncthreads();
+
+            // let one thread reserve the space required in the global list
+            if (threadIdx.x == 0 && threadIdx.y == 0)
+            {
+                // find how many items are stored in each list
+                int total_size = 0;
+                for (int i = 0; i < blockDim.y; ++i)
+                {
+                    s_start[i] = total_size;
+                    total_size += s_qsize[i];
+                }
+
+                // calculate the offset in the global list
+                const int global_offset = atomicAdd(&g_counter, total_size);
+                for (int i = 0; i < blockDim.y; ++i)
+                    s_start[i] += global_offset;
+            }
+
+            __syncthreads();
+
+            // copy local queues to global queue
+            const int qsize = s_qsize[threadIdx.y];
+            for(int i = threadIdx.x; i < qsize; i += blockDim.x)
+            {
+                const unsigned int val = s_queues[threadIdx.y][i];
+                list[s_start[threadIdx.y] + i] = val;
+            }
+        }
+
+        int buildPointList_gpu(DevMem2Db src, unsigned int* list)
+        {
+            void* counter_ptr;
+            cudaSafeCall( cudaGetSymbolAddress(&counter_ptr, g_counter) );
+
+            cudaSafeCall( cudaMemset(counter_ptr, 0, sizeof(int)) );
+
+            const dim3 block(32, 4);
+            const dim3 grid(divUp(src.cols, block.x * PIXELS_PER_THREAD), divUp(src.rows, block.y));
+
+            cudaSafeCall( cudaFuncSetCacheConfig(buildPointList, cudaFuncCachePreferShared) );
+
+            buildPointList<<<grid, block>>>(src, list);
+            cudaSafeCall( cudaGetLastError() );
+
+            cudaSafeCall( cudaDeviceSynchronize() );
+
+            int total_count;
+            cudaSafeCall( cudaMemcpy(&total_count, counter_ptr, sizeof(int), cudaMemcpyDeviceToHost) );
+
+            return total_count;
+        }
+
+        ////////////////////////////////////////////////////////////////////////
+        // linesAccum
+
+        __global__ void linesAccumGlobal(const unsigned int* list, const int count, PtrStepi accum, const float irho, const float theta, const int numrho)
+        {
+            const int n = blockIdx.x;
+            const float ang = n * theta;
+
+            float sin_ang;
+            float cos_ang;
+            sincosf(ang, &sin_ang, &cos_ang);
+
+            const float tabSin = sin_ang * irho;
+            const float tabCos = cos_ang * irho;
+
+            for (int i = threadIdx.x; i < count; i += blockDim.x)
+            {
+                const unsigned int qvalue = list[i];
+
+                const int x = (qvalue & 0x0000FFFF);
+                const int y = (qvalue >> 16) & 0x0000FFFF;
+
+                int r = __float2int_rn(x * tabCos + y * tabSin);
+                r += (numrho - 1) / 2;
+
+                ::atomicAdd(accum.ptr(n + 1) + r + 1, 1);
+            }
+        }
+
+        __global__ void linesAccumShared(const unsigned int* list, const int count, PtrStepi accum, const float irho, const float theta, const int numrho)
+        {
+            extern __shared__ int smem[];
+
+            for (int i = threadIdx.x; i < numrho + 1; i += blockDim.x)
+                smem[i] = 0;
+
+            __syncthreads();
+
+            const int n = blockIdx.x;
+            const float ang = n * theta;
+
+            float sin_ang;
+            float cos_ang;
+            sincosf(ang, &sin_ang, &cos_ang);
+
+            const float tabSin = sin_ang * irho;
+            const float tabCos = cos_ang * irho;
+
+            for (int i = threadIdx.x; i < count; i += blockDim.x)
+            {
+                const unsigned int qvalue = list[i];
+
+                const int x = (qvalue & 0x0000FFFF);
+                const int y = (qvalue >> 16) & 0x0000FFFF;
+
+                int r = __float2int_rn(x * tabCos + y * tabSin);
+                r += (numrho - 1) / 2;
+
+                Emulation::smem::atomicAdd(&smem[r + 1], 1);
+            }
+
+            __syncthreads();
+
+            for (int i = threadIdx.x; i < numrho; i += blockDim.x)
+                accum(n + 1, i) = smem[i];
+        }
+
+        void linesAccum_gpu(const unsigned int* list, int count, DevMem2Di accum, float rho, float theta, size_t sharedMemPerBlock)
+        {
+            const dim3 block(1024);
+            const dim3 grid(accum.rows - 2);
+
+            cudaSafeCall( cudaFuncSetCacheConfig(linesAccumShared, cudaFuncCachePreferShared) );
+
+            size_t smemSize = (accum.cols - 1) * sizeof(int);
+
+            if (smemSize < sharedMemPerBlock - 1000)
+                linesAccumShared<<<grid, block, smemSize>>>(list, count, accum, 1.0f / rho, theta, accum.cols - 2);
+            else
+                linesAccumGlobal<<<grid, block>>>(list, count, accum, 1.0f / rho, theta, accum.cols - 2);
+
+            cudaSafeCall( cudaGetLastError() );
+
+            cudaSafeCall( cudaDeviceSynchronize() );
+        }
+
+        ////////////////////////////////////////////////////////////////////////
+        // linesGetResult
+
+        __global__ void linesGetResult(const DevMem2Di accum, float2* out, int* votes, const int maxSize, const float threshold, const float theta, const float rho, const int numrho)
+        {
+            __shared__ int smem[8][32];
+
+            int r = blockIdx.x * (blockDim.x - 2) + threadIdx.x;
+            int n = blockIdx.y * (blockDim.y - 2) + threadIdx.y;
+
+            if (r >= accum.cols || n >= accum.rows)
+                return;
+
+            smem[threadIdx.y][threadIdx.x] = accum(n, r);
+            __syncthreads();
+
+            r -= 1;
+            n -= 1;
+
+            if (threadIdx.x == 0 || threadIdx.x == blockDim.x - 1 || threadIdx.y == 0 || threadIdx.y == blockDim.y - 1 || r >= accum.cols - 2 || n >= accum.rows - 2)
+                return;
+
+            if (smem[threadIdx.y][threadIdx.x] > threshold &&
+                smem[threadIdx.y][threadIdx.x] >  smem[threadIdx.y - 1][threadIdx.x] &&
+                smem[threadIdx.y][threadIdx.x] >= smem[threadIdx.y + 1][threadIdx.x] &&
+                smem[threadIdx.y][threadIdx.x] >  smem[threadIdx.y][threadIdx.x - 1] &&
+                smem[threadIdx.y][threadIdx.x] >= smem[threadIdx.y][threadIdx.x + 1])
+            {
+                const float radius = (r - (numrho - 1) * 0.5f) * rho;
+                const float angle = n * theta;
+
+                const int ind = ::atomicAdd(&g_counter, 1);
+                if (ind < maxSize)
+                {
+                    out[ind] = make_float2(radius, angle);
+                    votes[ind] = smem[threadIdx.y][threadIdx.x];
+                }
+            }
+        }
+
+        int linesGetResult_gpu(DevMem2Di accum, float2* out, int* votes, int maxSize, float rho, float theta, float threshold, bool doSort)
+        {
+            void* counter_ptr;
+            cudaSafeCall( cudaGetSymbolAddress(&counter_ptr, g_counter) );
+
+            cudaSafeCall( cudaMemset(counter_ptr, 0, sizeof(int)) );
+
+            const dim3 block(32, 8);
+            const dim3 grid(divUp(accum.cols, block.x - 2), divUp(accum.rows, block.y - 2));
+
+            linesGetResult<<<grid, block>>>(accum, out, votes, maxSize, threshold, theta, rho, accum.cols - 2);
+            cudaSafeCall( cudaGetLastError() );
+
+            cudaSafeCall( cudaDeviceSynchronize() );
+
+            int total_count;
+            cudaSafeCall( cudaMemcpy(&total_count, counter_ptr, sizeof(int), cudaMemcpyDeviceToHost) );
+
+            total_count = ::min(total_count, maxSize);
+
+            if (doSort && total_count > 0)
+            {
+                thrust::device_ptr<float2> out_ptr(out);
+                thrust::device_ptr<int> votes_ptr(votes);
+                thrust::sort_by_key(votes_ptr, votes_ptr + total_count, out_ptr, thrust::greater<int>());
+            }
+
+            return total_count;
+        }
+    }
+}}}

modules/gpu/src/hough.cpp

@@ -0,0 +1,144 @@
+/*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) 2000-2008, Intel Corporation, all rights reserved.
+// Copyright (C) 2009, Willow Garage 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 "precomp.hpp"
+
+#if !defined (HAVE_CUDA)
+
+void cv::gpu::HoughLinesTransform(const GpuMat&, GpuMat&, GpuMat&, float, float) { throw_nogpu(); }
+void cv::gpu::HoughLinesGet(const GpuMat&, GpuMat&, float, float, int, bool, int) { throw_nogpu(); }
+void cv::gpu::HoughLines(const GpuMat&, GpuMat&, float, float, int, bool, int) { throw_nogpu(); }
+void cv::gpu::HoughLines(const GpuMat&, GpuMat&, GpuMat&, GpuMat&, float, float, int, bool, int) { throw_nogpu(); }
+void cv::gpu::HoughLinesDownload(const GpuMat&, OutputArray, OutputArray) { throw_nogpu(); }
+
+#else /* !defined (HAVE_CUDA) */
+
+namespace cv { namespace gpu { namespace device
+{
+    namespace hough
+    {
+        int buildPointList_gpu(DevMem2Db src, unsigned int* list);
+        void linesAccum_gpu(const unsigned int* list, int count, DevMem2Di accum, float rho, float theta, size_t sharedMemPerBlock);
+        int linesGetResult_gpu(DevMem2Di accum, float2* out, int* votes, int maxSize, float rho, float theta, float threshold, bool doSort);
+    }
+}}}
+
+void cv::gpu::HoughLinesTransform(const GpuMat& src, GpuMat& accum, GpuMat& buf, float rho, float theta)
+{
+    using namespace cv::gpu::device::hough;
+
+    CV_Assert(src.type() == CV_8UC1);
+    CV_Assert(src.cols < std::numeric_limits<unsigned short>::max());
+    CV_Assert(src.rows < std::numeric_limits<unsigned short>::max());
+
+    ensureSizeIsEnough(1, src.size().area(), CV_32SC1, buf);
+
+    const int count = buildPointList_gpu(src, buf.ptr<unsigned int>());
+
+    const int numangle = cvRound(CV_PI / theta);
+    const int numrho = cvRound(((src.cols + src.rows) * 2 + 1) / rho);
+
+    CV_Assert(numangle > 0 && numrho > 0);
+
+    ensureSizeIsEnough(numangle + 2, numrho + 2, CV_32SC1, accum);
+    accum.setTo(cv::Scalar::all(0));
+
+    cv::gpu::DeviceInfo devInfo;
+
+    if (count > 0)
+        linesAccum_gpu(buf.ptr<unsigned int>(), count, accum, rho, theta, devInfo.sharedMemPerBlock());
+}
+
+void cv::gpu::HoughLinesGet(const GpuMat& accum, GpuMat& lines, float rho, float theta, int threshold, bool doSort, int maxLines)
+{
+    using namespace cv::gpu::device;
+
+    CV_Assert(accum.type() == CV_32SC1);
+
+    ensureSizeIsEnough(2, maxLines, CV_32FC2, lines);
+
+    int count = hough::linesGetResult_gpu(accum, lines.ptr<float2>(0), lines.ptr<int>(1), maxLines, rho, theta, threshold, doSort);
+
+    if (count > 0)
+        lines.cols = count;
+    else
+        lines.release();
+}
+
+void cv::gpu::HoughLines(const GpuMat& src, GpuMat& lines, float rho, float theta, int threshold, bool doSort, int maxLines)
+{
+    cv::gpu::GpuMat accum, buf;
+    HoughLines(src, lines, accum, buf, rho, theta, threshold, doSort, maxLines);
+}
+
+void cv::gpu::HoughLines(const GpuMat& src, GpuMat& lines, GpuMat& accum, GpuMat& buf, float rho, float theta, int threshold, bool doSort, int maxLines)
+{
+    HoughLinesTransform(src, accum, buf, rho, theta);
+    HoughLinesGet(accum, lines, rho, theta, threshold, doSort, maxLines);
+}
+
+void cv::gpu::HoughLinesDownload(const GpuMat& d_lines, OutputArray h_lines_, OutputArray h_votes_)
+{
+    if (d_lines.empty())
+    {
+        h_lines_.release();
+        if (h_votes_.needed())
+            h_votes_.release();
+        return;
+    }
+
+    CV_Assert(d_lines.rows == 2 && d_lines.type() == CV_32FC2);
+
+    h_lines_.create(1, d_lines.cols, CV_32FC2);
+    cv::Mat h_lines = h_lines_.getMat();
+    d_lines.row(0).download(h_lines);
+
+    if (h_votes_.needed())
+    {
+        h_votes_.create(1, d_lines.cols, CV_32SC1);
+        cv::Mat h_votes = h_votes_.getMat();
+        cv::gpu::GpuMat d_votes(1, d_lines.cols, CV_32SC1, const_cast<int*>(d_lines.ptr<int>(1)));
+        d_votes.download(h_votes);
+    }
+}
+
+#endif /* !defined (HAVE_CUDA) */

modules/gpu/src/opencv2/gpu/device/emulation.hpp

@@ -99,7 +99,7 @@ namespace cv { namespace gpu { namespace device
             }
 
             template<typename T>
-            static __device__ __forceinline__ void atomicAdd(T* address, T val)
+            static __device__ __forceinline__ T atomicAdd(T* address, T val)
             {
 #if defined (__CUDA_ARCH__) && (__CUDA_ARCH__ < 120)
                 T count;
@@ -110,8 +110,10 @@ namespace cv { namespace gpu { namespace device
                     count = tag | (count + val);
                     *address = count;
                 } while (*address != count);
+
+                return (count & TAG_MASK) - val;
 #else
-                ::atomicAdd(address, val);
+                return ::atomicAdd(address, val);
 #endif
             }
 

modules/gpu/test/test_imgproc.cpp

@@ -1124,4 +1124,65 @@ INSTANTIATE_TEST_CASE_P(GPU_ImgProc, CornerMinEigen, testing::Combine(
     testing::Values(BlockSize(3), BlockSize(5), BlockSize(7)),
     testing::Values(ApertureSize(0), ApertureSize(3), ApertureSize(5), ApertureSize(7))));
 
+///////////////////////////////////////////////////////////////////////////////////////////////////////
+// HoughLines
+
+PARAM_TEST_CASE(HoughLines, cv::gpu::DeviceInfo, std::string)
+{
+};
+
+void drawLines(cv::Mat& dst, const std::vector<cv::Vec2f>& lines)
+{
+    for (size_t i = 0; i < lines.size(); ++i)
+    {
+        float rho = lines[i][0], theta = lines[i][1];
+        cv::Point pt1, pt2;
+        double a = std::cos(theta), b = std::sin(theta);
+        double x0 = a*rho, y0 = b*rho;
+        pt1.x = cvRound(x0 + 1000*(-b));
+        pt1.y = cvRound(y0 + 1000*(a));
+        pt2.x = cvRound(x0 - 1000*(-b));
+        pt2.y = cvRound(y0 - 1000*(a));
+        cv::line(dst, pt1, pt2, cv::Scalar::all(255));
+    }
+}
+
+TEST_P(HoughLines, Accuracy)
+{
+    const cv::gpu::DeviceInfo devInfo = GET_PARAM(0);
+    cv::gpu::setDevice(devInfo.deviceID());
+    const std::string fileName = GET_PARAM(1);
+
+    const float rho = 1.0f;
+    const float theta = CV_PI / 180.0f;
+    const int threshold = 50;
+
+    cv::Mat img = readImage(fileName, cv::IMREAD_GRAYSCALE);
+    ASSERT_FALSE(img.empty());
+
+    cv::Mat edges;
+    cv::Canny(img, edges, 50, 200);
+
+    cv::gpu::GpuMat d_lines;
+    cv::gpu::HoughLines(loadMat(edges), d_lines, rho, theta, threshold);
+    std::vector<cv::Vec2f> lines;
+    cv::gpu::HoughLinesDownload(d_lines, lines);
+    cv::Mat dst(img.size(), CV_8UC1, cv::Scalar::all(0));
+    drawLines(dst, lines);
+
+    std::vector<cv::Vec2f> lines_gold;
+    cv::HoughLines(edges, lines_gold, rho, theta, threshold);
+    cv::Mat dst_gold(img.size(), CV_8UC1, cv::Scalar::all(0));
+    drawLines(dst_gold, lines_gold);
+
+    ASSERT_MAT_NEAR(dst_gold, dst, 0.0);
+}
+
+INSTANTIATE_TEST_CASE_P(GPU_ImgProc, HoughLines, testing::Combine(
+    ALL_DEVICES,
+    testing::Values(std::string("../cv/shared/pic1.png"),
+                    std::string("../cv/shared/pic3.png"),
+                    std::string("../cv/shared/pic5.png"),
+                    std::string("../cv/shared/pic6.png"))));
+
 } // namespace

modules/video/src/bgfg_gmg.cpp

@@ -197,7 +197,7 @@ namespace
         void operator() (const cv::Range& range) const;
 
     private:
-        const cv::Mat frame_;
+        cv::Mat frame_;
 
         mutable cv::Mat_<uchar> fgmask_;