FFmpeg合成h264视频流和aac音频流为mp4
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#include "MyMuxerToMP4.h"
#include <stdio.h>#include <libavcodec/avcodec.h>#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 1/* FIX:AAC in some container format (FLV, MP4, MKV etc.) need "aac_adtstoasc" bitstream filter (BSF) *///'1': Use AAC Bitstream Filter#define USE_AACBSF 1////static int open_input_file(const char *filename)//{// int ret;// AVCodec *dec;// // if ((ret = avformat_open_input(&pFormatCtx, filename, NULL, NULL)) < 0) {// printf( "Cannot open input file\n");// return ret;// }// // if ((ret = avformat_find_stream_info(pFormatCtx, NULL)) < 0) {// printf( "Cannot find stream information\n");// return ret;// }// // /* select the video stream */// ret = av_find_best_stream(pFormatCtx, AVMEDIA_TYPE_VIDEO, -1, -1, &dec, 0);// if (ret < 0) {// printf( "Cannot find a video stream in the input file\n");// return ret;// }// video_stream_index = ret;// pCodecCtx = pFormatCtx->streams[video_stream_index]->codec;// // /* init the video decoder */// if ((ret = avcodec_open2(pCodecCtx, dec, NULL)) < 0) {// printf( "Cannot open video decoder\n");// return ret;// }// // return 0;//}int muxer_main(char *inputH264FileName,char *inputAacFileName,char *outMP4FileName){ AVOutputFormat *ofmt =NULL; //Input AVFormatContext and Output AVFormatContext AVFormatContext *ifmt_ctx_v =NULL, *ifmt_ctx_a =NULL,*ofmt_ctx = NULL; AVPacket pkt; AVCodec *dec; int ret, i; int videoindex_v=-1,videoindex_out=-1; int audioindex_a=-1,audioindex_out=-1; int frame_index=0; int64_t cur_pts_v=0,cur_pts_a=0; //const char *in_filename_v = "cuc_ieschool.ts";//Input file URL constchar *in_filename_v =inputH264FileName; //const char *in_filename_a = "cuc_ieschool.mp3"; //const char *in_filename_a = "gowest.m4a"; //const char *in_filename_a = "gowest.aac"; constchar *in_filename_a =inputAacFileName; constchar *out_filename =outMP4FileName;//Output file URL printf("==========in h264==filename:%s\n",in_filename_v); printf("==========in aac ===filename:%s\n",in_filename_a); printf("==========outfile:%s\n",out_filename); avcodec_register_all(); av_register_all(); //Input if ((ret = avformat_open_input(&ifmt_ctx_a, in_filename_a,NULL,NULL)) <0) {// printf("=====11========RET:%d\n",ret); printf( "Could not open input file."); goto end; }// printf("=====2========RET:%d\n",ret); if ((ret = avformat_find_stream_info(ifmt_ctx_a,0)) <0) { printf( "Failed to retrieve input stream information"); goto end; } if ((ret = avformat_open_input(&ifmt_ctx_v, in_filename_v,NULL,NULL)) <0) { printf( "Could not open input file:%d\n",ret); goto end; }// printf("=====0========RET:%d\n",ret); if ((ret = avformat_find_stream_info(ifmt_ctx_v,0)) <0) { printf( "Failed to retrieve input stream information"); goto end; } // /* init the video decoder */// if ((ret = avcodec_open2(ifmt_ctx_a->, dec, NULL)) < 0) {// printf( "Cannot open video decoder\n");// return ret;// }// 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"); //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; for (i =0; i < ifmt_ctx_v->nb_streams; i++) { //Create output AVStream according to input AVStream if(ifmt_ctx_v->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO){ AVStream *in_stream = ifmt_ctx_v->streams[i]; AVStream *out_stream = avformat_new_stream(ofmt_ctx, in_stream->codec->codec); videoindex_v=i; if (!out_stream) { printf( "Failed allocating output stream\n"); ret = AVERROR_UNKNOWN; goto end; } videoindex_out=out_stream->index; //Copy the settings of AVCodecContext ret =av_dict_set(&out_stream->metadata,"rotate","90",0);//设置旋转角度 if(ret>=0) { printf("=========yes=====set rotate success!===\n"); } 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; } } for (i =0; i < ifmt_ctx_a->nb_streams; i++) { //Create output AVStream according to input AVStream if(ifmt_ctx_a->streams[i]->codec->codec_type==AVMEDIA_TYPE_AUDIO){ AVStream *in_stream = ifmt_ctx_a->streams[i]; AVStream *out_stream =avformat_new_stream(ofmt_ctx, in_stream->codec->codec); audioindex_a=i; if (!out_stream) { printf( "Failed allocating output stream\n"); ret = AVERROR_UNKNOWN; goto end; } audioindex_out=out_stream->index; //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; } } printf("==========Output Information==========\n"); av_dump_format(ofmt_ctx,0, out_filename,1); printf("======================================\n"); //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; } } //Write file header if (avformat_write_header(ofmt_ctx,NULL) < 0) { printf( "Error occurred when opening output file\n"); goto end; } //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; //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{ in_stream = ifmt_ctx->streams[pkt.stream_index]; out_stream = ofmt_ctx->streams[stream_index]; if(pkt.stream_index==videoindex_v){ //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++; } 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{ in_stream = ifmt_ctx->streams[pkt.stream_index]; out_stream = ofmt_ctx->streams[stream_index]; if(pkt.stream_index==audioindex_a){ //FIX£∫No PTS //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++; } cur_pts_a=pkt.pts; break; } }while(av_read_frame(ifmt_ctx, &pkt) >=0); }else{ break; } } //FIX:Bitstream Filter#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, out_stream->codec,NULL, &pkt.data, &pkt.size, pkt.data, pkt.size,0);#endif //Convert PTS/DTS pkt.pts = av_rescale_q_rnd(pkt.pts, in_stream->time_base, out_stream->time_base, (AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX)); pkt.dts = av_rescale_q_rnd(pkt.dts, in_stream->time_base, out_stream->time_base, (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:%lld\n",pkt.size,pkt.pts); //Write if (av_interleaved_write_frame(ofmt_ctx, &pkt) <0) { printf( "Error muxing packet\n"); break; } av_free_packet(&pkt); } //Write file trailer av_write_trailer(ofmt_ctx); #if USE_H264BSF av_bitstream_filter_close(h264bsfc);#endif#if USE_AACBSF av_bitstream_filter_close(aacbsfc);#endif end: avformat_close_input(&ifmt_ctx_v); avformat_close_input(&ifmt_ctx_a); /* 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("======muxer mp4 success =====!\n"); return0;}//==========2016年12月22日修改如下==================
因为按照上面的代码，一般的视频（如果aac不为空，也就是音频是有的话）是没有问题，但是如果aac是空文件，length=0，那合成就出问题！
于是解决这个问题，总代码如下：
//// MyMuxerToMP4.c// SFFmpegIOSTranscoder//// Created by lunil on 16/1/18.// Copyright © 2016年 Lei Xiaohua. All rights reserved.//#include "MyMuxerToMP4.h"#include <stdio.h>#include <libavcodec/avcodec.h>#include <libavformat/avformat.h>#include <stdlib.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 1/* FIX:AAC in some container format (FLV, MP4, MKV etc.) need "aac_adtstoasc" bitstream filter (BSF) *///'1': Use AAC Bitstream Filter#define USE_AACBSF 1static int open_input_file(const char *filename){ FILE *fp; fp=fopen(filename,"rb");// localfile文件名 fseek(fp,0L,SEEK_END); /* 定位到文件末尾 */ int flen=ftell(fp); /* 得到文件大小 */ //printf("=====22222======filename %s,length:%d",filename,flen); return flen;}int muxer_main(char *inputH264FileName,char *inputAacFileName,char *outMP4FileName,char* angle){ AVOutputFormat *ofmt = NULL; //Input AVFormatContext and Output AVFormatContext AVFormatContext *ifmt_ctx_v = NULL, *ifmt_ctx_a = NULL,*ofmt_ctx = NULL; AVPacket pkt; AVCodec *dec; int ret, i; int videoindex_v=-1,videoindex_out=-1; int audioindex_a=-1,audioindex_out=-1; int frame_index=0; int64_t cur_pts_v=0,cur_pts_a=0; //const char *in_filename_v = "cuc_ieschool.ts";//Input file URL const char *in_filename_v =inputH264FileName; //const char *in_filename_a = "cuc_ieschool.mp3"; //const char *in_filename_a = "gowest.m4a"; //const char *in_filename_a = "gowest.aac"; const char *in_filename_a =inputAacFileName; const char *out_filename =outMP4FileName;//Output file URL printf("==========in h264==filename:%s\n",in_filename_v); printf("==========in aac ===filename:%s\n",in_filename_a); //int video_length=open_input_file(in_filename_v); //=========判断如果视频中没有音频，会导致avformat_find_stream_info退出程序====== int acc_length=open_input_file(in_filename_a); //如果音频是空，则不需要放入视频 avcodec_register_all(); av_register_all(); //Input if ((ret = avformat_open_input(&ifmt_ctx_a, in_filename_a, NULL, NULL)) < 0) { // printf("=====11========RET:%d\n",ret); printf( "Could not open input file."); goto end; } // printf("=====2========RET:%d\n",ret); if ((ret = avformat_find_stream_info(ifmt_ctx_a, 0)) < 0) { printf( "Failed to retrieve input stream information"); if(acc_length>0) //如果音频是空，则直接到结尾，否则继续运行 goto end; } if ((ret = avformat_open_input(&ifmt_ctx_v, in_filename_v, NULL, NULL)) < 0) { printf( "Could not open input file:%d\n",ret); goto end; } // printf("=====0========RET:%d\n",ret); if ((ret = avformat_find_stream_info(ifmt_ctx_v, 0)) < 0) { printf( "Failed to retrieve input stream information"); goto end; } // /* init the video decoder */ // if ((ret = avcodec_open2(ifmt_ctx_a->, dec, NULL)) < 0) { // printf( "Cannot open video decoder\n"); // return ret; // } // 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"); //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; for (i = 0; i < ifmt_ctx_v->nb_streams; i++) { //Create output AVStream according to input AVStream if(ifmt_ctx_v->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO){ AVStream *in_stream = ifmt_ctx_v->streams[i]; AVStream *out_stream = avformat_new_stream(ofmt_ctx, in_stream->codec->codec); videoindex_v=i; if (!out_stream) { printf( "Failed allocating output stream\n"); ret = AVERROR_UNKNOWN; goto end; } videoindex_out=out_stream->index; //Copy the settings of AVCodecContext ret = av_dict_set(&out_stream->metadata,"rotate",angle,0); //设置旋转角度 if(ret>=0) { printf("=========yes=====set rotate success!===:%s\n",angle); } 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; } } if(acc_length>0) //如果音频文件有内容，则读取，否则为空读取会失败 { for (i = 0; i < ifmt_ctx_a->nb_streams; i++) { printf("===========acc=====from======:%d\n",ifmt_ctx_a->nb_streams); //Create output AVStream according to input AVStream if(ifmt_ctx_a->streams[i]->codec->codec_type==AVMEDIA_TYPE_AUDIO){ AVStream *in_stream = ifmt_ctx_a->streams[i]; AVStream *out_stream = avformat_new_stream(ofmt_ctx, in_stream->codec->codec); audioindex_a=i; if (!out_stream) { printf( "Failed allocating output stream\n"); ret = AVERROR_UNKNOWN; goto end; } audioindex_out=out_stream->index; //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; } } } printf("==========Output Information==========\n"); av_dump_format(ofmt_ctx, 0, out_filename, 1); printf("======================================\n"); //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; } } //Write file header int header_ret=avformat_write_header(ofmt_ctx, NULL); if (header_ret< 0) { printf( "Error occurred when opening output file:%d\n",header_ret); goto end; } //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; //Get an AVPacket int compare_tag=-1; if(acc_length>0) //既然没有音频，则直接判断写入视频 { compare_tag =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) ; } if(compare_tag<= 0){ ifmt_ctx=ifmt_ctx_v; stream_index=videoindex_out; if(av_read_frame(ifmt_ctx, &pkt) >= 0){ do{ in_stream = ifmt_ctx->streams[pkt.stream_index]; out_stream = ofmt_ctx->streams[stream_index]; if(pkt.stream_index==videoindex_v){ //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++; } 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{ in_stream = ifmt_ctx->streams[pkt.stream_index]; out_stream = ofmt_ctx->streams[stream_index]; if(pkt.stream_index==audioindex_a){ //FIX£∫No PTS //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++; } cur_pts_a=pkt.pts; break; } }while(av_read_frame(ifmt_ctx, &pkt) >= 0); }else{ break; } } //FIX:Bitstream Filter#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, out_stream->codec, NULL, &pkt.data, &pkt.size, pkt.data, pkt.size, 0);#endif //Convert PTS/DTS pkt.pts = av_rescale_q_rnd(pkt.pts, in_stream->time_base, out_stream->time_base, (AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX)); pkt.dts = av_rescale_q_rnd(pkt.dts, in_stream->time_base, out_stream->time_base, (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:%lld\n",pkt.size,pkt.pts); //Write if (av_interleaved_write_frame(ofmt_ctx, &pkt) < 0) { printf( "Error muxing packet\n"); break; } av_free_packet(&pkt); } //Write file trailer av_write_trailer(ofmt_ctx); #if USE_H264BSF av_bitstream_filter_close(h264bsfc);#endif#if USE_AACBSF av_bitstream_filter_close(aacbsfc);#endif end: avformat_close_input(&ifmt_ctx_v); avformat_close_input(&ifmt_ctx_a); /* 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("======muxer mp4 success =====!\n"); return 0;}解决方案就是先判断文件是不是空的，然后只把视频封装进mp4容器即可。会有一些警告，但是完全ok！
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