ffmpeg 转换es流成为ps流

目的是将es流转换成为ps流

写入到文件中

#include <libavformat/avformat.h>
#include <libavcodec/avcodec.h>
#include <libavutil/avutil.h>
#include <libavutil/timestamp.h>int main(int argc, char** argv) {const char* input_filename = "input.mp4"; // 输入文件名const char* output_filename = "output.ps"; // 输出PS文件名// 初始化FFmpegav_register_all();avformat_network_init();// 打开输入文件AVFormatContext* ifmt_ctx = NULL;if (avformat_open_input(&ifmt_ctx, input_filename, 0, 0) < 0) {fprintf(stderr, "Could not open input file '%s'\n", input_filename);return -1;}// 获取输入流信息if (avformat_find_stream_info(ifmt_ctx, 0) < 0) {fprintf(stderr, "Failed to retrieve input stream information\n");return -1;}// 打开输出文件AVFormatContext* ofmt_ctx = NULL;avformat_alloc_output_context2(&ofmt_ctx, NULL, "mpeg", output_filename);if (!ofmt_ctx) {printf("Could not create output context\n");return -1;}// 复制流并设置输出参数for (unsigned int i = 0; i < ifmt_ctx->nb_streams; i++) {AVStream* in_stream = ifmt_ctx->streams[i];AVStream* out_stream = avformat_new_stream(ofmt_ctx, in_stream->codecpar->codec);if (!out_stream) {fprintf(stderr, "Failed allocating output stream\n");return -1;}avcodec_parameters_copy(out_stream->codecpar, in_stream->codecpar);out_stream->time_base = in_stream->time_base;}// 打开输出文件的输出流if (!(ofmt_ctx->oformat->flags & AVFMT_NOFILE)) {if (avio_open(&ofmt_ctx->pb, output_filename, AVIO_FLAG_WRITE) < 0) {fprintf(stderr, "Could not open output file '%s'\n", output_filename);return -1;}}// 写入文件头if (avformat_write_header(ofmt_ctx, NULL) < 0) {fprintf(stderr, "Error occurred when opening output file\n");return -1;}// 重采样和转封装的逻辑通常在这里，但因为我们只是简单地转封装，可以使用av_interleaved_write_frame直接写入AVPacket pkt;while (1) {AVStream* in_stream, *out_stream;if (av_read_frame(ifmt_ctx, &pkt) >= 0) {in_stream  = ifmt_ctx->streams[pkt.stream_index];out_stream = ofmt_ctx->streams[pkt.stream_index];// 设置pts/dtspkt.pts = av_rescale_q_rnd(pkt.pts, in_stream->time_base, out_stream->time_base, (AVRounding)(AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX));pkt.dts = av_rescale_q_rnd(pkt.dts, in_stream->time_base, out_stream->time_base, (AVRounding)(AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX));pkt.duration = av_rescale_q(pkt.duration, in_stream->time_base, out_stream->time_base);pkt.pos = -1;// 写入包if (av_interleaved_write_frame(ofmt_ctx, &pkt) < 0) {fprintf(stderr, "Error muxing packet\n");break;}av_packet_unref(&pkt);} else {break;}}// 写入尾部并关闭文件av_write_trailer(ofmt_ctx);if (ofmt_ctx && !(ofmt_ctx->oformat->flags & AVFMT_NOFILE))avio_closep(&ofmt_ctx->pb);// 释放资源avformat_close_input(&ifmt_ctx);avformat_free_context(ofmt_ctx);return 0;
}

写入到缓存

#include <stdio.h>
#include <stdlib.h>
#include <libavformat/avformat.h>int main(int argc, char *argv[]) {AVFormatContext *inFormatContext = NULL;AVFormatContext *outFormatContext = NULL;AVOutputFormat *outputFormat = NULL;AVPacket packet;int ret;uint8_t *psBuffer = NULL;int psBufferSize = 0;// 注册所有的FFmpeg组件av_register_all();// 打开输入文件ret = avformat_open_input(&inFormatContext, argv[1], NULL, NULL);if (ret < 0) {fprintf(stderr, "无法打开输入文件\n");return -1;}// 查找流信息ret = avformat_find_stream_info(inFormatContext, NULL);if (ret < 0) {fprintf(stderr, "无法获取流信息\n");return -1;}// 打开输出文件outFormatContext = avformat_alloc_context();if (!outFormatContext) {fprintf(stderr, "无法创建输出文件上下文\n");return -1;}outputFormat = av_guess_format(NULL, "output.ps", NULL);if (!outputFormat) {fprintf(stderr, "无法猜测输出格式\n");return -1;}outFormatContext->oformat = outputFormat;// 逐个处理输入文件的流for (int i = 0; i < inFormatContext->nb_streams; i++) {AVStream *inStream = inFormatContext->streams[i];AVStream *outStream = avformat_new_stream(outFormatContext, NULL);if (!outStream) {fprintf(stderr, "无法创建输出流\n");return -1;}ret = avcodec_parameters_copy(outStream->codecpar, inStream->codecpar);if (ret < 0) {fprintf(stderr, "无法复制编解码参数\n");return -1;}}// 分配内存缓冲区avio_open_dyn_buf(&outFormatContext->pb);// 写入输出文件的头部信息ret = avformat_write_header(outFormatContext, NULL);if (ret < 0) {fprintf(stderr, "无法写入输出文件的头部信息\n");return -1;}// 读取数据包并写入内存缓冲区while (av_read_frame(inFormatContext, &packet) >= 0) {// 将数据包写入内存缓冲区ret = av_write_frame(outFormatContext, &packet);if (ret < 0) {fprintf(stderr, "无法写入数据包\n");break;}av_packet_unref(&packet);}// 写入输出文件的尾部信息av_write_trailer(outFormatContext);// 获取内存缓冲区的大小和数据指针psBufferSize = avio_close_dyn_buf(outFormatContext->pb, &psBuffer);// 对PS数据进行处理，例如可以将其写入文件或进行其他操作// 注意：psBuffer 现在包含了整个PS流的数据，其大小为psBufferSize// 释放资源avformat_close_input(&inFormatContext);avformat_free_context(outFormatContext);av_free(psBuffer);return 0;
}