Merge pull request #1355 from jet47:gpu-stereo-multi-gpu-sample

samples/gpu/stereo_multi.cpp

-/* This sample demonstrates working on one piece of data using two GPUs.
-   It splits input into two parts and processes them separately on different
-   GPUs. */
+// This sample demonstrates working on one piece of data using two GPUs.
+// It splits input into two parts and processes them separately on different GPUs.
 
-// Disable some warnings which are caused with CUDA headers
-#if defined(_MSC_VER)
-#pragma warning(disable: 4201 4408 4100)
+#ifdef WIN32
+    #define NOMINMAX
+    #include <windows.h>
+#else
+    #include <pthread.h>
+    #include <unistd.h>
 #endif
 
 #include <iostream>
-#include "cvconfig.h"
+#include <iomanip>
+
 #include "opencv2/core/core.hpp"
 #include "opencv2/highgui/highgui.hpp"
+#include "opencv2/imgproc/imgproc.hpp"
+#include "opencv2/contrib/contrib.hpp"
 #include "opencv2/gpu/gpu.hpp"
 
-#if !defined(HAVE_CUDA) || !defined(HAVE_TBB)
+using namespace std;
+using namespace cv;
+using namespace cv::gpu;
+
+///////////////////////////////////////////////////////////
+// Thread
+// OS-specific wrappers for multi-threading
 
-int main()
+#ifdef WIN32
+class Thread
 {
-#if !defined(HAVE_CUDA)
-    std::cout << "CUDA support is required (CMake key 'WITH_CUDA' must be true).\n";
-#endif
+    struct UserData
+    {
+        void (*func)(void* userData);
+        void* param;
+    };
+
+    static DWORD WINAPI WinThreadFunction(LPVOID lpParam)
+    {
+        UserData* userData = static_cast<UserData*>(lpParam);
+
+        userData->func(userData->param);
+
+        return 0;
+    }
+
+    UserData userData_;
+    HANDLE thread_;
+    DWORD threadId_;
+
+public:
+    Thread(void (*func)(void* userData), void* userData)
+    {
+        userData_.func = func;
+        userData_.param = userData;
+
+        thread_ = CreateThread(
+            NULL,                   // default security attributes
+            0,                      // use default stack size
+            WinThreadFunction,      // thread function name
+            &userData_,             // argument to thread function
+            0,                      // use default creation flags
+            &threadId_);            // returns the thread identifier
+    }
+
+    ~Thread()
+    {
+        CloseHandle(thread_);
+    }
+
+    void wait()
+    {
+        WaitForSingleObject(thread_, INFINITE);
+    }
+};
+#else
+class Thread
+{
+    struct UserData
+    {
+        void (*func)(void* userData);
+        void* param;
+    };
+
+    static void* PThreadFunction(void* lpParam)
+    {
+        UserData* userData = static_cast<UserData*>(lpParam);
+
+        userData->func(userData->param);
+
+        return 0;
+    }
+
+    pthread_t thread_;
+    UserData userData_;
+
+public:
+    Thread(void (*func)(void* userData), void* userData)
+    {
+        userData_.func = func;
+        userData_.param = userData;
+
+        pthread_create(&thread_, NULL, PThreadFunction, &userData_);
+    }
 
-#if !defined(HAVE_TBB)
-    std::cout << "TBB support is required (CMake key 'WITH_TBB' must be true).\n";
+    ~Thread()
+    {
+        pthread_detach(thread_);
+    }
+
+    void wait()
+    {
+        pthread_join(thread_, NULL);
+    }
+};
 #endif
 
-    return 0;
+///////////////////////////////////////////////////////////
+// StereoSingleGpu
+// Run Stereo algorithm on single GPU
+
+class StereoSingleGpu
+{
+public:
+    explicit StereoSingleGpu(int deviceId = 0);
+    ~StereoSingleGpu();
+
+    void compute(const Mat& leftFrame, const Mat& rightFrame, Mat& disparity);
+
+private:
+    int deviceId_;
+    GpuMat d_leftFrame;
+    GpuMat d_rightFrame;
+    GpuMat d_disparity;
+    Ptr<StereoBM_GPU> d_alg;
+};
+
+StereoSingleGpu::StereoSingleGpu(int deviceId) : deviceId_(deviceId)
+{
+    gpu::setDevice(deviceId_);
+    d_alg = new StereoBM_GPU(StereoBM_GPU::BASIC_PRESET, 256);
 }
 
-#else
+StereoSingleGpu::~StereoSingleGpu()
+{
+    gpu::setDevice(deviceId_);
+    d_leftFrame.release();
+    d_rightFrame.release();
+    d_disparity.release();
+    d_alg.release();
+}
 
-#include "opencv2/core/internal.hpp" // For TBB wrappers
+void StereoSingleGpu::compute(const Mat& leftFrame, const Mat& rightFrame, Mat& disparity)
+{
+    gpu::setDevice(deviceId_);
+    d_leftFrame.upload(leftFrame);
+    d_rightFrame.upload(rightFrame);
+    (*d_alg)(d_leftFrame, d_rightFrame, d_disparity);
+    d_disparity.download(disparity);
+}
 
-using namespace std;
-using namespace cv;
-using namespace cv::gpu;
+///////////////////////////////////////////////////////////
+// StereoMultiGpuThread
+// Run Stereo algorithm on two GPUs using different host threads
+
+class StereoMultiGpuThread
+{
+public:
+    StereoMultiGpuThread();
+    ~StereoMultiGpuThread();
+
+    void compute(const Mat& leftFrame, const Mat& rightFrame, Mat& disparity);
+
+private:
+    GpuMat d_leftFrames[2];
+    GpuMat d_rightFrames[2];
+    GpuMat d_disparities[2];
+    Ptr<StereoBM_GPU> d_algs[2];
+
+    struct StereoLaunchData
+    {
+        int deviceId;
+        Mat leftFrame;
+        Mat rightFrame;
+        Mat disparity;
+        GpuMat* d_leftFrame;
+        GpuMat* d_rightFrame;
+        GpuMat* d_disparity;
+        Ptr<StereoBM_GPU> d_alg;
+    };
+
+    static void launchGpuStereoAlg(void* userData);
+};
+
+StereoMultiGpuThread::StereoMultiGpuThread()
+{
+    gpu::setDevice(0);
+    d_algs[0] = new StereoBM_GPU(StereoBM_GPU::BASIC_PRESET, 256);
+
+    gpu::setDevice(1);
+    d_algs[1] = new StereoBM_GPU(StereoBM_GPU::BASIC_PRESET, 256);
+}
+
+StereoMultiGpuThread::~StereoMultiGpuThread()
+{
+    gpu::setDevice(0);
+    d_leftFrames[0].release();
+    d_rightFrames[0].release();
+    d_disparities[0].release();
+    d_algs[0].release();
+
+    gpu::setDevice(1);
+    d_leftFrames[1].release();
+    d_rightFrames[1].release();
+    d_disparities[1].release();
+    d_algs[1].release();
+}
+
+void StereoMultiGpuThread::compute(const Mat& leftFrame, const Mat& rightFrame, Mat& disparity)
+{
+    disparity.create(leftFrame.size(), CV_8UC1);
+
+    // Split input data onto two parts for each GPUs.
+    // We add small border for each part,
+    // because original algorithm doesn't calculate disparity on image borders.
+    // With such padding we will get output in the middle of final result.
+
+    StereoLaunchData launchDatas[2];
+
+    launchDatas[0].deviceId = 0;
+    launchDatas[0].leftFrame = leftFrame.rowRange(0, leftFrame.rows / 2 + 32);
+    launchDatas[0].rightFrame = rightFrame.rowRange(0, rightFrame.rows / 2 + 32);
+    launchDatas[0].disparity = disparity.rowRange(0, leftFrame.rows / 2);
+    launchDatas[0].d_leftFrame = &d_leftFrames[0];
+    launchDatas[0].d_rightFrame = &d_rightFrames[0];
+    launchDatas[0].d_disparity = &d_disparities[0];
+    launchDatas[0].d_alg = d_algs[0];
+
+    launchDatas[1].deviceId = 1;
+    launchDatas[1].leftFrame = leftFrame.rowRange(leftFrame.rows / 2 - 32, leftFrame.rows);
+    launchDatas[1].rightFrame = rightFrame.rowRange(leftFrame.rows / 2 - 32, leftFrame.rows);
+    launchDatas[1].disparity = disparity.rowRange(leftFrame.rows / 2, leftFrame.rows);
+    launchDatas[1].d_leftFrame = &d_leftFrames[1];
+    launchDatas[1].d_rightFrame = &d_rightFrames[1];
+    launchDatas[1].d_disparity = &d_disparities[1];
+    launchDatas[1].d_alg = d_algs[1];
 
-struct Worker { void operator()(int device_id) const; };
+    Thread thread0(launchGpuStereoAlg, &launchDatas[0]);
+    Thread thread1(launchGpuStereoAlg, &launchDatas[1]);
 
-// GPUs data
-GpuMat d_left[2];
-GpuMat d_right[2];
-StereoBM_GPU* bm[2];
-GpuMat d_result[2];
+    thread0.wait();
+    thread1.wait();
+}
 
-static void printHelp()
+void StereoMultiGpuThread::launchGpuStereoAlg(void* userData)
 {
-    std::cout << "Usage: stereo_multi_gpu --left <image> --right <image>\n";
+    StereoLaunchData* data = static_cast<StereoLaunchData*>(userData);
+
+    gpu::setDevice(data->deviceId);
+    data->d_leftFrame->upload(data->leftFrame);
+    data->d_rightFrame->upload(data->rightFrame);
+    (*data->d_alg)(*data->d_leftFrame, *data->d_rightFrame, *data->d_disparity);
+
+    if (data->deviceId == 0)
+        data->d_disparity->rowRange(0, data->d_disparity->rows - 32).download(data->disparity);
+    else
+        data->d_disparity->rowRange(32, data->d_disparity->rows).download(data->disparity);
 }
 
+///////////////////////////////////////////////////////////
+// StereoMultiGpuStream
+// Run Stereo algorithm on two GPUs from single host thread using async API
+
+class StereoMultiGpuStream
+{
+public:
+    StereoMultiGpuStream();
+    ~StereoMultiGpuStream();
+
+    void compute(const CudaMem& leftFrame, const CudaMem& rightFrame, CudaMem& disparity);
+
+private:
+    GpuMat d_leftFrames[2];
+    GpuMat d_rightFrames[2];
+    GpuMat d_disparities[2];
+    Ptr<StereoBM_GPU> d_algs[2];
+    Ptr<Stream> streams[2];
+};
+
+StereoMultiGpuStream::StereoMultiGpuStream()
+{
+    gpu::setDevice(0);
+    d_algs[0] = new StereoBM_GPU(StereoBM_GPU::BASIC_PRESET, 256);
+    streams[0] = new Stream;
+
+    gpu::setDevice(1);
+    d_algs[1] = new StereoBM_GPU(StereoBM_GPU::BASIC_PRESET, 256);
+    streams[1] = new Stream;
+}
+
+StereoMultiGpuStream::~StereoMultiGpuStream()
+{
+    gpu::setDevice(0);
+    d_leftFrames[0].release();
+    d_rightFrames[0].release();
+    d_disparities[0].release();
+    d_algs[0].release();
+    streams[0].release();
+
+    gpu::setDevice(1);
+    d_leftFrames[1].release();
+    d_rightFrames[1].release();
+    d_disparities[1].release();
+    d_algs[1].release();
+    streams[1].release();
+}
+
+void StereoMultiGpuStream::compute(const CudaMem& leftFrame, const CudaMem& rightFrame, CudaMem& disparity)
+{
+    disparity.create(leftFrame.size(), CV_8UC1);
+
+    // Split input data onto two parts for each GPUs.
+    // We add small border for each part,
+    // because original algorithm doesn't calculate disparity on image borders.
+    // With such padding we will get output in the middle of final result.
+
+    Mat leftFrameHdr = leftFrame.createMatHeader();
+    Mat rightFrameHdr = rightFrame.createMatHeader();
+    Mat disparityHdr = disparity.createMatHeader();
+    Mat disparityPart0 = disparityHdr.rowRange(0, leftFrame.rows / 2);
+    Mat disparityPart1 = disparityHdr.rowRange(leftFrame.rows / 2, leftFrame.rows);
+
+    gpu::setDevice(0);
+    streams[0]->enqueueUpload(leftFrameHdr.rowRange(0, leftFrame.rows / 2 + 32), d_leftFrames[0]);
+    streams[0]->enqueueUpload(rightFrameHdr.rowRange(0, leftFrame.rows / 2 + 32), d_rightFrames[0]);
+    (*d_algs[0])(d_leftFrames[0], d_rightFrames[0], d_disparities[0], *streams[0]);
+    streams[0]->enqueueDownload(d_disparities[0].rowRange(0, leftFrame.rows / 2), disparityPart0);
+
+    gpu::setDevice(1);
+    streams[1]->enqueueUpload(leftFrameHdr.rowRange(leftFrame.rows / 2 - 32, leftFrame.rows), d_leftFrames[1]);
+    streams[1]->enqueueUpload(rightFrameHdr.rowRange(leftFrame.rows / 2 - 32, leftFrame.rows), d_rightFrames[1]);
+    (*d_algs[1])(d_leftFrames[1], d_rightFrames[1], d_disparities[1], *streams[1]);
+    streams[1]->enqueueDownload(d_disparities[1].rowRange(32, d_disparities[1].rows), disparityPart1);
+
+    gpu::setDevice(0);
+    streams[0]->waitForCompletion();
+
+    gpu::setDevice(1);
+    streams[1]->waitForCompletion();
+}
+
+///////////////////////////////////////////////////////////
+// main
+
 int main(int argc, char** argv)
 {
-    if (argc < 5)
+    if (argc != 3)
     {
-        printHelp();
+        cerr << "Usage: stereo_multi_gpu <left_video> <right_video>" << endl;
         return -1;
     }
 
-    int num_devices = getCudaEnabledDeviceCount();
-    if (num_devices < 2)
+    const int numDevices = getCudaEnabledDeviceCount();
+    if (numDevices != 2)
     {
-        std::cout << "Two or more GPUs are required\n";
+        cerr << "Two GPUs are required" << endl;
         return -1;
     }
-    for (int i = 0; i < num_devices; ++i)
-    {
-        cv::gpu::printShortCudaDeviceInfo(i);
 
-        DeviceInfo dev_info(i);
-        if (!dev_info.isCompatible())
+    for (int i = 0; i < numDevices; ++i)
+    {
+        DeviceInfo devInfo(i);
+        if (!devInfo.isCompatible())
         {
-            std::cout << "GPU module isn't built for GPU #" << i << " ("
-                 << dev_info.name() << ", CC " << dev_info.majorVersion()
-                 << dev_info.minorVersion() << "\n";
+            cerr << "GPU module was't built for GPU #" << i << " ("
+                 << devInfo.name() << ", CC " << devInfo.majorVersion()
+                 << devInfo.minorVersion() << endl;
             return -1;
         }
+
+        printShortCudaDeviceInfo(i);
     }
 
-    // Load input data
-    Mat left, right;
-    for (int i = 1; i < argc; ++i)
+    VideoCapture leftVideo(argv[1]);
+    VideoCapture rightVideo(argv[2]);
+
+    if (!leftVideo.isOpened())
     {
-        if (string(argv[i]) == "--left")
-        {
-            left = imread(argv[++i], CV_LOAD_IMAGE_GRAYSCALE);
-            CV_Assert(!left.empty());
-        }
-        else if (string(argv[i]) == "--right")
-        {
-            right = imread(argv[++i], CV_LOAD_IMAGE_GRAYSCALE);
-            CV_Assert(!right.empty());
-        }
-        else if (string(argv[i]) == "--help")
+         cerr << "Can't open " << argv[1] << " video file" << endl;
+         return -1;
+    }
+
+    if (!rightVideo.isOpened())
+    {
+         cerr << "Can't open " << argv[2] << " video file" << endl;
+         return -1;
+    }
+
+    cout << endl;
+    cout << "This sample demonstrates working on one piece of data using two GPUs." << endl;
+    cout << "It splits input into two parts and processes them separately on different GPUs." << endl;
+    cout << endl;
+
+    Mat leftFrame, rightFrame;
+    CudaMem leftGrayFrame, rightGrayFrame;
+
+    StereoSingleGpu gpu0Alg(0);
+    StereoSingleGpu gpu1Alg(1);
+    StereoMultiGpuThread multiThreadAlg;
+    StereoMultiGpuStream multiStreamAlg;
+
+    Mat disparityGpu0;
+    Mat disparityGpu1;
+    Mat disparityMultiThread;
+    CudaMem disparityMultiStream;
+
+    Mat disparityGpu0Show;
+    Mat disparityGpu1Show;
+    Mat disparityMultiThreadShow;
+    Mat disparityMultiStreamShow;
+
+    TickMeter tm;
+
+    cout << "-------------------------------------------------------------------" << endl;
+    cout << "| Frame | GPU 0 ms | GPU 1 ms | Multi Thread ms | Multi Stream ms |" << endl;
+    cout << "-------------------------------------------------------------------" << endl;
+
+    for (int i = 0;; ++i)
+    {
+        leftVideo >> leftFrame;
+        rightVideo >> rightFrame;
+
+        if (leftFrame.empty() || rightFrame.empty())
+            break;
+
+        if (leftFrame.size() != rightFrame.size())
         {
-            printHelp();
+            cerr << "Frames have different sizes" << endl;
             return -1;
         }
-    }
 
-    // Split source images for processing on the GPU #0
-    setDevice(0);
-    d_left[0].upload(left.rowRange(0, left.rows / 2));
-    d_right[0].upload(right.rowRange(0, right.rows / 2));
-    bm[0] = new StereoBM_GPU();
-
-    // Split source images for processing on the GPU #1
-    setDevice(1);
-    d_left[1].upload(left.rowRange(left.rows / 2, left.rows));
-    d_right[1].upload(right.rowRange(right.rows / 2, right.rows));
-    bm[1] = new StereoBM_GPU();
-
-    // Execute calculation in two threads using two GPUs
-    int devices[] = {0, 1};
-    parallel_do(devices, devices + 2, Worker());
-
-    // Release the first GPU resources
-    setDevice(0);
-    imshow("GPU #0 result", Mat(d_result[0]));
-    d_left[0].release();
-    d_right[0].release();
-    d_result[0].release();
-    delete bm[0];
-
-    // Release the second GPU resources
-    setDevice(1);
-    imshow("GPU #1 result", Mat(d_result[1]));
-    d_left[1].release();
-    d_right[1].release();
-    d_result[1].release();
-    delete bm[1];
-
-    waitKey();
-    return 0;
-}
+        leftGrayFrame.create(leftFrame.size(), CV_8UC1);
+        rightGrayFrame.create(leftFrame.size(), CV_8UC1);
 
+        cvtColor(leftFrame, leftGrayFrame.createMatHeader(), COLOR_BGR2GRAY);
+        cvtColor(rightFrame, rightGrayFrame.createMatHeader(), COLOR_BGR2GRAY);
 
-void Worker::operator()(int device_id) const
-{
-    setDevice(device_id);
+        tm.reset(); tm.start();
+        gpu0Alg.compute(leftGrayFrame, rightGrayFrame, disparityGpu0);
+        tm.stop();
 
-    bm[device_id]->operator()(d_left[device_id], d_right[device_id],
-                              d_result[device_id]);
+        const double gpu0Time = tm.getTimeMilli();
 
-    std::cout << "GPU #" << device_id << " (" << DeviceInfo().name()
-        << "): finished\n";
-}
+        tm.reset(); tm.start();
+        gpu1Alg.compute(leftGrayFrame, rightGrayFrame, disparityGpu1);
+        tm.stop();
 
-#endif
+        const double gpu1Time = tm.getTimeMilli();
+
+        tm.reset(); tm.start();
+        multiThreadAlg.compute(leftGrayFrame, rightGrayFrame, disparityMultiThread);
+        tm.stop();
+
+        const double multiThreadTime = tm.getTimeMilli();
+
+        tm.reset(); tm.start();
+        multiStreamAlg.compute(leftGrayFrame, rightGrayFrame, disparityMultiStream);
+        tm.stop();
+
+        const double multiStreamTime = tm.getTimeMilli();
+
+        cout << "| " << setw(5) << i << " | "
+             << setw(8) << setprecision(1) << fixed << gpu0Time << " | "
+             << setw(8) << setprecision(1) << fixed << gpu1Time << " | "
+             << setw(15) << setprecision(1) << fixed << multiThreadTime << " | "
+             << setw(15) << setprecision(1) << fixed << multiStreamTime << " |" << endl;
+
+        resize(disparityGpu0, disparityGpu0Show, Size(1024, 768), 0, 0, INTER_AREA);
+        resize(disparityGpu1, disparityGpu1Show, Size(1024, 768), 0, 0, INTER_AREA);
+        resize(disparityMultiThread, disparityMultiThreadShow, Size(1024, 768), 0, 0, INTER_AREA);
+        resize(disparityMultiStream.createMatHeader(), disparityMultiStreamShow, Size(1024, 768), 0, 0, INTER_AREA);
+
+        imshow("disparityGpu0", disparityGpu0Show);
+        imshow("disparityGpu1", disparityGpu1Show);
+        imshow("disparityMultiThread", disparityMultiThreadShow);
+        imshow("disparityMultiStream", disparityMultiStreamShow);
+
+        const int key = waitKey(30) & 0xff;
+        if (key == 27)
+            break;
+    }
+
+    cout << "-------------------------------------------------------------------" << endl;
+
+    return 0;
+}