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站在巨人的肩膀上最简单的基于FFMPEG的封装格式转换器（无编解码）_mp4remuxer_雷霄骅的博客-CSDN博客

在作者的示例上,修正了在ffmpeg6.0.1上运行,有些方法过时了.没有其它的修改.

const char *in_filename = "/Users/archko/Movie/健身气功八段锦-clip.mp4";const char *out_filename = "/Users/archko/Movie/code.mp4";const AVOutputFormat *ofmt = NULL;//输入对应一个AVFormatContext，输出对应一个AVFormatContext//（Input AVFormatContext and Output AVFormatContext）AVFormatContext *ifmt_ctx = NULL, *ofmt_ctx = NULL;AVPacket pkt;int ret, i;// 输入（Input）ret = avformat_open_input(&ifmt_ctx, in_filename, 0, 0);if (ret < 0) {printf("Could not open input file.");return 0;}ret = avformat_find_stream_info(ifmt_ctx, 0);if (ret < 0) {printf("Failed to retrieve input stream information");return 0;}av_dump_format(ifmt_ctx, 0, in_filename, 0);//输出（Output）avformat_alloc_output_context2(&ofmt_ctx, NULL, NULL, out_filename);if (!ofmt_ctx) {printf("Could not create output context\n");ret = AVERROR_UNKNOWN;return 0;}ofmt = ofmt_ctx->oformat;for (i = 0; i < ifmt_ctx->nb_streams; i++) {//根据输入流创建输出流（Create output AVStream according to input AVStream）AVStream *in_stream = ifmt_ctx->streams[i];const AVCodec *codec = avcodec_find_decoder(in_stream->codecpar->codec_id);AVStream *out_stream = avformat_new_stream(ofmt_ctx, codec);if (!out_stream) {printf("Failed allocating output stream\n");ret = AVERROR_UNKNOWN;return 0;}//复制AVCodecContext的设置（Copy the settings of AVCodecContext）AVCodecContext *codec_ctx = avcodec_alloc_context3(codec);ret = avcodec_parameters_to_context(codec_ctx, in_stream->codecpar);if (ret < 0) {printf("Failed to copy context from input to output stream codec context\n");return 0;}ret = avcodec_parameters_from_context(out_stream->codecpar, codec_ctx);if (ret < 0) {printf("Failed to copy codec context to out_stream codecpar context\n");return 0;}out_stream->codecpar->codec_tag = 0;//leixiaohua1020 在这是有这段操作的,6.0不需要这样,然后正常复制视频//if (ofmt_ctx->oformat->flags & AVFMT_GLOBALHEADER) {//    out_stream->codecpar->codec_tag |= AV_CODEC_FLAG_GLOBAL_HEADER;//}}//输出一下格式------------------av_dump_format(ofmt_ctx, 0, out_filename, 1);//打开输出文件（Open output file）if (!(ofmt->flags & AVFMT_NOFILE)) {ret = avio_open(&ofmt_ctx->pb, out_filename, AVIO_FLAG_WRITE);if (ret < 0) {printf("Could not open output file '%s'", out_filename);return 0;}}//写文件头（Write file header）ret = avformat_write_header(ofmt_ctx, NULL);if (ret < 0) {printf("Error occurred when opening output file\n");return 0;}int frame_index = 0;while (1) {AVStream *in_stream, *out_stream;//获取一个AVPacket（Get an AVPacket）ret = av_read_frame(ifmt_ctx, &pkt);if (ret < 0)break;in_stream = ifmt_ctx->streams[pkt.stream_index];out_stream = ofmt_ctx->streams[pkt.stream_index];/* copy packet *///转换PTS/DTS（Convert PTS/DTS）pkt.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（Write）ret = av_interleaved_write_frame(ofmt_ctx, &pkt);if (ret < 0) {printf("Error muxing packet\n");break;}//printf("Write %8d frames to output file\n", frame_index);av_packet_unref(&pkt);frame_index++;}//写文件尾（Write file trailer）av_write_trailer(ofmt_ctx);end:avformat_close_input(&ifmt_ctx);/* close output */if (ofmt_ctx && !(ofmt->flags & AVFMT_NOFILE)) {avio_close(ofmt_ctx->pb);}avformat_free_context(ofmt_ctx);if (ret < 0 && ret != AVERROR_EOF) {printf("Error occurred.\n");return -1;}printf("Copy success.\n");return 0;

xcode的开发实在不习惯,用的是clion,cmake,vscode.下一篇,clion创建项目,导入ffmpeg依赖