/* 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) #endif #include <iostream> #include "opencv2/cvconfig.h" #include "opencv2/core.hpp" #include "opencv2/highgui.hpp" #include "opencv2/cudastereo.hpp" #ifdef HAVE_TBB # include "tbb/tbb.h" # include "tbb/task.h" # undef min # undef max #endif #if !defined(HAVE_CUDA) || !defined(HAVE_TBB) || defined(__arm__) int main() { #if !defined(HAVE_CUDA) std::cout << "CUDA support is required (CMake key 'WITH_CUDA' must be true).\n"; #endif #if !defined(HAVE_TBB) std::cout << "TBB support is required (CMake key 'WITH_TBB' must be true).\n"; #endif #if defined(__arm__) std::cout << "Unsupported for ARM CUDA library." << std::endl; #endif return 0; } #else #include <cuda.h> #include <cuda_runtime.h> using namespace std; using namespace cv; using namespace cv::cuda; struct Worker { void operator()(int device_id) const; }; void destroyContexts(); #define safeCall(expr) safeCall_(expr, #expr, __FILE__, __LINE__) inline void safeCall_(int code, const char* expr, const char* file, int line) { if (code != CUDA_SUCCESS) { std::cout << "CUDA driver API error: code " << code << ", expr " << expr << ", file " << file << ", line " << line << endl; destroyContexts(); exit(-1); } } // Each GPU is associated with its own context CUcontext contexts[2]; void inline contextOn(int id) { safeCall(cuCtxPushCurrent(contexts[id])); } void inline contextOff() { CUcontext prev_context; safeCall(cuCtxPopCurrent(&prev_context)); } // GPUs data GpuMat d_left[2]; GpuMat d_right[2]; Ptr<cuda::StereoBM> bm[2]; GpuMat d_result[2]; static void printHelp() { std::cout << "Usage: driver_api_stereo_multi --left <left_image> --right <right_image>\n"; } int main(int argc, char** argv) { if (argc < 5) { printHelp(); return -1; } int num_devices = getCudaEnabledDeviceCount(); if (num_devices < 2) { std::cout << "Two or more GPUs are required\n"; return -1; } for (int i = 0; i < num_devices; ++i) { cv::cuda::printShortCudaDeviceInfo(i); DeviceInfo dev_info(i); if (!dev_info.isCompatible()) { std::cout << "GPU module isn't built for GPU #" << i << " (" << dev_info.name() << ", CC " << dev_info.majorVersion() << dev_info.minorVersion() << "\n"; return -1; } } // Load input data Mat left, right; for (int i = 1; i < argc; ++i) { if (string(argv[i]) == "--left") { left = imread(argv[++i], cv::IMREAD_GRAYSCALE); CV_Assert(!left.empty()); } else if (string(argv[i]) == "--right") { right = imread(argv[++i], cv::IMREAD_GRAYSCALE); CV_Assert(!right.empty()); } else if (string(argv[i]) == "--help") { printHelp(); return -1; } } // Init CUDA Driver API safeCall(cuInit(0)); // Create context for GPU #0 CUdevice device; safeCall(cuDeviceGet(&device, 0)); safeCall(cuCtxCreate(&contexts[0], 0, device)); contextOff(); // Create context for GPU #1 safeCall(cuDeviceGet(&device, 1)); safeCall(cuCtxCreate(&contexts[1], 0, device)); contextOff(); // Split source images for processing on GPU #0 contextOn(0); d_left[0].upload(left.rowRange(0, left.rows / 2)); d_right[0].upload(right.rowRange(0, right.rows / 2)); bm[0] = cuda::createStereoBM(); contextOff(); // Split source images for processing on the GPU #1 contextOn(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] = cuda::createStereoBM(); contextOff(); // Execute calculation in two threads using two GPUs int devices[] = {0, 1}; tbb::parallel_do(devices, devices + 2, Worker()); // Release the first GPU resources contextOn(0); imshow("GPU #0 result", Mat(d_result[0])); d_left[0].release(); d_right[0].release(); d_result[0].release(); bm[0].release(); contextOff(); // Release the second GPU resources contextOn(1); imshow("GPU #1 result", Mat(d_result[1])); d_left[1].release(); d_right[1].release(); d_result[1].release(); bm[1].release(); contextOff(); waitKey(); destroyContexts(); return 0; } void Worker::operator()(int device_id) const { contextOn(device_id); bm[device_id]->compute(d_left[device_id], d_right[device_id], d_result[device_id]); std::cout << "GPU #" << device_id << " (" << DeviceInfo().name() << "): finished\n"; contextOff(); } void destroyContexts() { safeCall(cuCtxDestroy(contexts[0])); safeCall(cuCtxDestroy(contexts[1])); } #endif