存储的ps 流文件如何显示
使用ffmpeg 和 opencv 做demo
结合opencv 和 ffmpeg 显示ps文件
// 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 fileAVFormatContext* 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 streamint 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 streamconst 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 decoderAVCodecContext* 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 SwsContextAVFrame* 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 OpenCVAVPacket packet;while (av_read_frame(format_context, &packet) >= 0) {if (packet.stream_index == video_stream_index) {// Decode the frameint 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 BGRAVFrame* 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 Matcv::Mat bgrMat(codec_context->height, codec_context->width, CV_8UC3, bgr_frame->data[0]);// Display using OpenCVcv::imshow("Frame", bgrMat);cv::waitKey(1);// Free resourcesav_frame_free(&bgr_frame);}}av_packet_unref(&packet);}// Free resourcesav_frame_free(&frame);sws_freeContext(sws_context);avcodec_free_context(&codec_context);avformat_close_input(&format_context);return 0;
}