#include <iostream>

#include "opencv2/opencv_modules.hpp"

#if defined(HAVE_OPENCV_CUDACODEC)

#include <string>

#include <vector>

#include <algorithm>

#include <numeric>

#include <opencv2/core.hpp>

#include <opencv2/core/opengl.hpp>

#include <opencv2/cudacodec.hpp>

#include <opencv2/highgui.hpp>

int main(int argc, const char* argv[])

{

if (argc != 2)

return -1;

const std::string fname(argv[1]);

cv::namedWindow("CPU", cv::WINDOW_NORMAL);

#if defined(HAVE_OPENGL)

cv::namedWindow("GPU", cv::WINDOW_OPENGL);

cv::cuda::setGlDevice();

#else

cv::namedWindow("GPU", cv::WINDOW_NORMAL);

#endif

cv::TickMeter tm;

cv::Mat frame;

cv::VideoCapture reader(fname);

for (;;)

{

if (!reader.read(frame))

break;

cv::imshow("CPU", frame);

if (cv::waitKey(3) > 0)

break;

}

cv::cuda::GpuMat d_frame;

cv::Ptr<cv::cudacodec::VideoReader> d_reader = cv::cudacodec::createVideoReader(fname);

for (;;)

{

if (!d_reader->nextFrame(d_frame))

break;

#if defined(HAVE_OPENGL)

cv::imshow("GPU", cv::ogl::Texture2D(d_frame));

#else

d_frame.download(frame);

cv::imshow("GPU", frame);

#endif

if (cv::waitKey(3) > 0)

break;

}

return 0;

}

#else

int main()

{

std::cout << "OpenCV was built without CUDA Video decoding support\n" << std::endl;

return 0;

}

#endif