// showps.cpp : 此文件包含 "main" 函数。程序执行将在此处开始并结束。 // #include <iostream> #include <opencv2/opencv.hpp> extern "C" { #include <libavcodec/avcodec.h> #include <libavformat/avformat.h> #include <libswscale/swscale.h> } #ifdef _WIN32 #pragma comment(lib,"avutil.lib") #pragma comment(lib,"avcodec.lib") #pragma comment(lib,"avformat.lib") #pragma comment(lib,"swscale.lib") #endif #ifdef _DEBUG #pragma comment(lib,"opencv_world490d.lib") #else #pragma comment(lib,"opencv_world490.lib") #endif #define AV_ERROR_REPORT char buffer[64];\ av_strerror(ret, &buffer[0], 64);\ std::cerr << "Error sending packet to decoder: " << buffer << std::endl int main() { // Initialize FFmpeg // Open video file AVFormatContext* format_context = avformat_alloc_context(); const AVInputFormat* input_format = av_find_input_format("mpeg"); if (!input_format) { std::cerr << "Failed to find input format" << std::endl; return -1; } format_context->iformat = input_format; if (avformat_open_input(&format_context, "o1.ps", nullptr, nullptr) != 0) { std::cerr << "Failed to open input file" << std::endl; return -1; } if (avformat_find_stream_info(format_context, nullptr) < 0) { std::cerr << "Failed to find stream info" << std::endl; avformat_close_input(&format_context); return -1; } // Find video stream int video_stream_index = -1; for (unsigned int i = 0; i < format_context->nb_streams; ++i) { if (format_context->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) { video_stream_index = i; break; } } video_stream_index = 0; if (video_stream_index == -1) { std::cerr << "No video stream found" << std::endl; avformat_close_input(&format_context); return -1; } // Find decoder for the stream const AVCodec* codec = avcodec_find_decoder(format_context->streams[video_stream_index]->codecpar->codec_id); if (!codec) { std::cerr << "Failed to find decoder for video stream" << std::endl; avformat_close_input(&format_context); return -1; } // Create codec context for the decoder AVCodecContext* codec_context = avcodec_alloc_context3(codec); if (!codec_context) { std::cerr << "Failed to allocate codec context" << std::endl; avformat_close_input(&format_context); return -1; } if (avcodec_parameters_to_context(codec_context, format_context->streams[video_stream_index]->codecpar) < 0) { std::cerr << "Failed to copy codec parameters to codec context" << std::endl; avcodec_free_context(&codec_context); avformat_close_input(&format_context); return -1; } if (avcodec_open2(codec_context, codec, nullptr) < 0) { std::cerr << "Failed to open codec" << std::endl; avcodec_free_context(&codec_context); avformat_close_input(&format_context); return -1; } // Allocate video frame and initialize SwsContext AVFrame* frame = av_frame_alloc(); if (!frame) { std::cerr << "Failed to allocate frame" << std::endl; avcodec_free_context(&codec_context); avformat_close_input(&format_context); return -1; } struct SwsContext* sws_context = sws_getContext(codec_context->width, codec_context->height, codec_context->pix_fmt, codec_context->width, codec_context->height, AV_PIX_FMT_BGR24, SWS_BILINEAR, nullptr, nullptr, nullptr); if (!sws_context) { std::cerr << "Failed to initialize SwsContext" << std::endl; av_frame_free(&frame); avcodec_free_context(&codec_context); avformat_close_input(&format_context); return -1; } // Read frames from the stream and display using OpenCV AVPacket packet; while (av_read_frame(format_context, &packet) >= 0) { if (packet.stream_index == video_stream_index) { // Decode the frame int ret = avcodec_send_packet(codec_context, &packet); if (ret < 0) { AV_ERROR_REPORT; break; } while (ret >= 0) { ret = avcodec_receive_frame(codec_context, frame); if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) break; else if (ret < 0) { AV_ERROR_REPORT; break; } // Convert frame to BGR AVFrame* bgr_frame = av_frame_alloc(); if (!bgr_frame) { std::cerr << "Failed to allocate BGR frame" << std::endl; break; } bgr_frame->width = codec_context->width; bgr_frame->height = codec_context->height; bgr_frame->format = AV_PIX_FMT_BGR24; av_frame_get_buffer(bgr_frame, 0); sws_scale(sws_context, frame->data, frame->linesize, 0, codec_context->height, bgr_frame->data, bgr_frame->linesize); // Convert AVFrame to OpenCV Mat cv::Mat bgrMat(codec_context->height, codec_context->width, CV_8UC3, bgr_frame->data[0]); // Display using OpenCV cv::imshow("Frame", bgrMat); cv::waitKey(1); // Free resources av_frame_free(&bgr_frame); } } av_packet_unref(&packet); } // Free resources av_frame_free(&frame); sws_freeContext(sws_context); avcodec_free_context(&codec_context); avformat_close_input(&format_context); return 0; }