diff --git a/samples/cpp/videocapture_camera.cpp b/samples/cpp/videocapture_camera.cpp new file mode 100644 index 0000000000..4d5a341657 --- /dev/null +++ b/samples/cpp/videocapture_camera.cpp @@ -0,0 +1,76 @@ +#include +#include +#include +#include // cv::Canny() +#include + +using namespace cv; +using std::cout; using std::cerr; using std::endl; + +int main(int, char**) +{ + Mat frame; + cout << "Opening camera..." << endl; + VideoCapture capture(-1); // open the first available camera + if (!capture.isOpened()) + { + cerr << "ERROR: Can't initialize camera capture" << endl; + return 1; + } + + cout << "Frame width: " << capture.get(CAP_PROP_FRAME_WIDTH) << endl; + cout << " height: " << capture.get(CAP_PROP_FRAME_HEIGHT) << endl; + cout << "Capturing FPS: " << capture.get(CAP_PROP_FPS) << endl; + + cout << endl << "Press 'ESC' to quit, 'space' to toggle frame processing" << endl; + cout << endl << "Start grabbing..." << endl; + + size_t nFrames = 0; + bool enableProcessing = false; + int64 t0 = cv::getTickCount(); + int64 processingTime = 0; + for (;;) + { + capture >> frame; // read the next frame from camera + if (frame.empty()) + { + cerr << "ERROR: Can't grab camera frame." << endl; + break; + } + nFrames++; + if (nFrames % 10 == 0) + { + const int N = 10; + int64 t1 = cv::getTickCount(); + cout << "Frames captured: " << cv::format("%5lld", (long long int)nFrames) + << " Average FPS: " << cv::format("%9.1f", (double)getTickFrequency() * N / (t1 - t0)) + << " Average time per frame: " << cv::format("%9.2f ms", (double)(t1 - t0) * 1000.0f / (N * getTickFrequency())) + << " Average processing time: " << cv::format("%9.2f ms", (double)(processingTime) * 1000.0f / (N * getTickFrequency())) + << std::endl; + t0 = t1; + processingTime = 0; + } + if (!enableProcessing) + { + imshow("Frame", frame); + } + else + { + int64 tp0 = cv::getTickCount(); + Mat processed; + cv::Canny(frame, processed, 400, 1000, 5); + processingTime += cv::getTickCount() - tp0; + imshow("Frame", processed); + } + int key = waitKey(1); + if (key == 27/*ESC*/) + break; + if (key == 32/*SPACE*/) + { + enableProcessing = !enableProcessing; + cout << "Enable frame processing ('space' key): " << enableProcessing << endl; + } + } + std::cout << "Number of captured frames: " << nFrames << endl; + return nFrames > 0 ? 0 : 1; +}