最简单的基于FFmpeg的封装格式处理的例子

/** * 最简单的基于FFmpeg的视音频复用器 * Simplest FFmpeg Muxer * * 雷霄骅 Lei Xiaohua * leixiaohua1020@126.com * 中国传媒大学/数字电视技术 * Communication University of China / Digital TV Technology * http://blog.csdn.net/leixiaohua1020 * * 本程序可以将视频码流和音频码流打包到一种封装格式中。 * 程序中将AAC编码的音频码流和H.264编码的视频码流打包成 * MPEG2TS封装格式的文件。 * 需要注意的是本程序并不改变视音频的编码格式。 * * This software mux a video bitstream and a audio bitstream * together into a file. * In this example, it mux a H.264 bitstream (in MPEG2TS) and * a AAC bitstream file together into MP4 format file. * */ #include <stdio.h> extern "C" { #include "libavformat/avformat.h" }; /* FIX: H.264 in some container format (FLV, MP4, MKV etc.) need "h264_mp4toannexb" bitstream filter (BSF) *Add SPS,PPS in front of IDR frame *Add start code ("0,0,0,1") in front of NALU H.264 in some container (MPEG2TS) don't need this BSF. */ //'1': Use H.264 Bitstream Filter #define USE_H264BSF 0 /* FIX:AAC in some container format (FLV, MP4, MKV etc.) need "aac_adtstoasc" bitstream filter (BSF) */ //'1': Use AAC Bitstream Filter #define USE_AACBSF 0 int main(int argc, char* argv[]) { 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_v = NULL, *ifmt_ctx_a = NULL,*ofmt_ctx = NULL; AVPacket pkt; int ret, i; char *in_filename_v = "cuc_ieschool.ts";//输入文件名（Input file URL） //char *in_filename_v = "cuc_ieschool.h264"; //char *in_filename_a = "cuc_ieschool.mp3"; //char *in_filename_a = "gowest.m4a"; //char *in_filename_a = "gowest.aac"; char *in_filename_a = "huoyuanjia.mp3"; char *out_filename = "cuc_ieschool.mp4";//输出文件名（Output file URL） av_register_all(); //输入（Input） if ((ret = avformat_open_input(&ifmt_ctx_v, in_filename_v, 0, 0)) < 0) { printf( "Could not open input file."); goto end; } if ((ret = avformat_find_stream_info(ifmt_ctx_v, 0)) < 0) { printf( "Failed to retrieve input stream information"); goto end; } if ((ret = avformat_open_input(&ifmt_ctx_a, in_filename_a, 0, 0)) < 0) { printf( "Could not open input file."); goto end; } if ((ret = avformat_find_stream_info(ifmt_ctx_a, 0)) < 0) { printf( "Failed to retrieve input stream information"); goto end; } printf("Input Information=====================\n"); av_dump_format(ifmt_ctx_v, 0, in_filename_v, 0); av_dump_format(ifmt_ctx_a, 0, in_filename_a, 0); printf("======================================\n"); //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; goto end; } ofmt = ofmt_ctx->oformat; int videoindex_v=-1,videoindex_out=-1; for (i = 0; i < ifmt_ctx_v->nb_streams; i++) { //根据输入流创建输出流（Create output AVStream according to input AVStream） if(ifmt_ctx_v->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO){ videoindex_v=i; AVStream *in_stream = ifmt_ctx_v->streams[i]; AVStream *out_stream = avformat_new_stream(ofmt_ctx, in_stream->codec->codec); if (!out_stream) { printf( "Failed allocating output stream\n"); ret = AVERROR_UNKNOWN; goto end; } videoindex_out=out_stream->index; //复制AVCodecContext的设置（Copy the settings of AVCodecContext） if (avcodec_copy_context(out_stream->codec, in_stream->codec) < 0) { printf( "Failed to copy context from input to output stream codec context\n"); goto end; } out_stream->codec->codec_tag = 0; if (ofmt_ctx->oformat->flags & AVFMT_GLOBALHEADER) out_stream->codec->flags |= CODEC_FLAG_GLOBAL_HEADER; break; } } int audioindex_a=-1,audioindex_out=-1; for (i = 0; i < ifmt_ctx_a->nb_streams; i++) { //根据输入流创建输出流（Create output AVStream according to input AVStream） if(ifmt_ctx_a->streams[i]->codec->codec_type==AVMEDIA_TYPE_AUDIO){ audioindex_a=i; AVStream *in_stream = ifmt_ctx_a->streams[i]; AVStream *out_stream = avformat_new_stream(ofmt_ctx, in_stream->codec->codec); if (!out_stream) { printf( "Failed allocating output stream\n"); ret = AVERROR_UNKNOWN; goto end; } audioindex_out=out_stream->index; //复制AVCodecContext的设置（Copy the settings of AVCodecContext） if (avcodec_copy_context(out_stream->codec, in_stream->codec) < 0) { printf( "Failed to copy context from input to output stream codec context\n"); goto end; } out_stream->codec->codec_tag = 0; if (ofmt_ctx->oformat->flags & AVFMT_GLOBALHEADER) out_stream->codec->flags |= CODEC_FLAG_GLOBAL_HEADER; break; } } //输出一下格式------------------ printf("Output Information====================\n"); av_dump_format(ofmt_ctx, 0, out_filename, 1); printf("======================================\n"); //打开输出文件（Open output file） if (!(ofmt->flags & AVFMT_NOFILE)) { if (avio_open(&ofmt_ctx->pb, out_filename, AVIO_FLAG_WRITE) < 0) { printf( "Could not open output file '%s'", out_filename); goto end; } } //写文件头（Write file header） if (avformat_write_header(ofmt_ctx, NULL) < 0) { printf( "Error occurred when opening output file\n"); goto end; } int frame_index=0; int64_t cur_pts_v=0,cur_pts_a=0; //FIX #if USE_H264BSF AVBitStreamFilterContext* h264bsfc = av_bitstream_filter_init("h264_mp4toannexb"); #endif #if USE_AACBSF AVBitStreamFilterContext* aacbsfc = av_bitstream_filter_init("aac_adtstoasc"); #endif while (1) { AVFormatContext *ifmt_ctx; int stream_index=0; AVStream *in_stream, *out_stream; //获取一个AVPacket（Get an AVPacket） if(av_compare_ts(cur_pts_v,ifmt_ctx_v->streams[videoindex_v]->time_base,cur_pts_a,ifmt_ctx_a->streams[audioindex_a]->time_base) <= 0){ ifmt_ctx=ifmt_ctx_v; stream_index=videoindex_out; if(av_read_frame(ifmt_ctx, &pkt) >= 0){ do{ if(pkt.stream_index==videoindex_v){ cur_pts_v=pkt.pts; break; } }while(av_read_frame(ifmt_ctx, &pkt) >= 0); }else{ break; } }else{ ifmt_ctx=ifmt_ctx_a; stream_index=audioindex_out; if(av_read_frame(ifmt_ctx, &pkt) >= 0){ do{ if(pkt.stream_index==audioindex_a){ cur_pts_a=pkt.pts; break; } }while(av_read_frame(ifmt_ctx, &pkt) >= 0); }else{ break; } } in_stream = ifmt_ctx->streams[pkt.stream_index]; out_stream = ofmt_ctx->streams[stream_index]; //FIX #if USE_H264BSF av_bitstream_filter_filter(h264bsfc, in_stream->codec, NULL, &pkt.data, &pkt.size, pkt.data, pkt.size, 0); #endif #if USE_AACBSF av_bitstream_filter_filter(aacbsfc, in_stream->codec, NULL, &pkt.data, &pkt.size, pkt.data, pkt.size, 0); #endif //FIX：No PTS (Example: Raw H.264) //Simple Write PTS if(pkt.pts==AV_NOPTS_VALUE){ //Write PTS AVRational time_base1=in_stream->time_base; //Duration between 2 frames (us) int64_t calc_duration=(double)AV_TIME_BASE/av_q2d(in_stream->r_frame_rate); //Parameters pkt.pts=(double)(frame_index*calc_duration)/(double)(av_q2d(time_base1)*AV_TIME_BASE); pkt.dts=pkt.pts; pkt.duration=(double)calc_duration/(double)(av_q2d(time_base1)*AV_TIME_BASE); frame_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; pkt.stream_index=stream_index; printf("Write 1 Packet. size:%5d\tpts:%8d\n