展台设计网站推荐,windows系统优化软件排行榜,爱站工具seo综合查询,阿里云网站建设方案书中山市ffmepeg 4.4#xff08;亲测可用#xff09; 一、使用FFMPEG库封装264视频和acc音频数据到 mp4/flv 文件中 封装流程 1.使用avformat_open_input分别打开视频和音频文件#xff0c;初始化其AVFormatContext#xff0c;使用avformat_find_stream_info获取编码器基本信息 2.使… ffmepeg 4.4亲测可用 一、使用FFMPEG库封装264视频和acc音频数据到 mp4/flv 文件中 封装流程 1.使用avformat_open_input分别打开视频和音频文件初始化其AVFormatContext使用avformat_find_stream_info获取编码器基本信息 2.使用avformat_alloc_output_context2初始化输出的AVFormatContext结构 3.使用函数avformat_new_stream给输出的AVFormatContext结构创建音频和视频流使用avcodec_parameters_copy方法将音视频的编码参数拷贝到新创建的对应的流的codecpar结构中 4.使用avio_open打开输出文件初始化输出AVFormatContext结构中的IO上下文结构 5.使用avformat_write_header写入流的头信息到输出文件中 6.根据时间戳同步原则交错写入音视频数据并对时间戳信息进行设置和校准 7.写入流预告信息到输出文件中moov 8.释放空间关闭文件 【mp4_muxer.cpp】 #include stdio.h#define __STDC_CONSTANT_MACROS#ifdef _WIN32//Windows
extern C
{
#include libavformat/avformat.h
};
#else//Linux...
#ifdef __cplusplus
extern C
{
#endif
#include libavformat/avformat.h
#ifdef __cplusplus
};
#endif
#endifint main(int argc, char* argv[]) {const AVOutputFormat* ofmt NULL;//Input AVFormatContext and Output AVFormatContextAVFormatContext* ifmt_ctx_v NULL, * ifmt_ctx_a NULL, * ofmt_ctx NULL;AVPacket pkt;int ret;unsigned int 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;int writing_v 1, writing_a 1;const char* in_filename_v test.h264;const char* in_filename_a audio_chn0.aac;const char* out_filename test.mp4;//Output file URLif ((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;}//Outputavformat_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 AVStreamif (ifmt_ctx_v-streams[i]-codecpar-codec_type AVMEDIA_TYPE_VIDEO) {AVStream* out_stream avformat_new_stream(ofmt_ctx, nullptr);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 AVCodecContextif (avcodec_parameters_copy(out_stream-codecpar, ifmt_ctx_v-streams[i]-codecpar) 0) {printf(Failed to copy context from input to output stream codec context\n);goto end;}break;}}for (i 0; i ifmt_ctx_a-nb_streams; i) {//Create output AVStream according to input AVStreamif (ifmt_ctx_a-streams[i]-codecpar-codec_type AVMEDIA_TYPE_AUDIO) {AVStream* out_stream avformat_new_stream(ofmt_ctx, nullptr);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 AVCodecContextif (avcodec_parameters_copy(out_stream-codecpar, ifmt_ctx_a-streams[i]-codecpar) 0) {printf(Failed to copy context from input to output stream codec context\n);goto end;}out_stream-codecpar-codec_tag 0;if (ofmt_ctx-oformat-flags AVFMT_GLOBALHEADER)ofmt_ctx-flags | AV_CODEC_FLAG_GLOBAL_HEADER;break;}}/* open the output file, if needed */if (!(ofmt-flags AVFMT_NOFILE)) {if (avio_open(ofmt_ctx-pb, out_filename, AVIO_FLAG_WRITE)) {fprintf(stderr, Could not open %s: %d\n, out_filename,ret);goto end;}}//Write file headerif (avformat_write_header(ofmt_ctx, NULL) 0) {fprintf(stderr, Error occurred when opening output file: %d\n,ret);goto end;}//写入数据while (writing_v || writing_a){AVFormatContext* ifmt_ctx;int stream_index 0;AVStream* in_stream, * out_stream;int av_type 0;if (writing_v (!writing_a || 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)){av_type 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){//FIXNo PTS (Example: Raw H.264)//Simple Write PTSif (pkt.pts AV_NOPTS_VALUE){//Write PTSAVRational 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);//Parameterspkt.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;printf(frame_index: %d\n, frame_index);}cur_pts_v pkt.pts;break;}} while(av_read_frame(ifmt_ctx, pkt) 0);}else{writing_v 0;continue;}}else{av_type 1;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){//FIXNo PTS//Simple Write PTSif (pkt.pts AV_NOPTS_VALUE){//Write PTSAVRational 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);//Parameterspkt.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{writing_a 0;continue;}}//Convert 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;pkt.stream_index stream_index;printf(Write 1 Packet. type:%d, size:%d\tpts:%ld\n, av_type, pkt.size, pkt.pts);//Writeif (av_interleaved_write_frame(ofmt_ctx, pkt) 0) {printf(Error muxing packet\n);break;}av_packet_unref(pkt);}printf(Write file trailer.\n);//Write file trailerav_write_trailer(ofmt_ctx);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;}return 0;
} 【Makefile】 CROSS_COMPILE aarch64-himix200-linux-CC $(CROSS_COMPILE)g
AR $(CROSS_COMPILE)ar
STRIP $(CROSS_COMPILE)stripCFLAGS -Wall -O2 -I../../source/mp4Lib/include
LIBS -L../../source/mp4Lib/lib -lpthread
LIBS -lavformat -lavcodec -lavdevice -lavutil -lavfilter -lswscale -lswresample -lzSRCS $(wildcard *.cpp)
OBJS $(SRCS:%.cpp%.o)
DEPS $(SRCS:%.cpp%.d)
TARGET mp4muxerall:$(TARGET)-include $(DEPS)%.o:%.cpp$(CC) $(CFLAGS) -c -o $ $%.d:%.cset -e; rm -f $; \$(CC) -MM $(CFLAGS) $ $.$$$$; \sed s,\($*\)\.o[ :]*,\1.o $ : ,g $.$$$$ $; \rm -f $.$$$$$(TARGET):$(OBJS)$(CC) -o $ $^ $(LIBS)$(STRIP) $ .PHONY:cleanclean:rm -fr $(TARGET) $(OBJS) $(DEPS) 二、使用FFMPEG分离mp4/flv文件中的264视频和aac音频 分离流程 1.使用avformat_open_input 函数打开文件并初始化结构AVFormatContext 2.查找是否存在音频和视频信息 3.构建一个h264_mp4toannexb比特流的过滤器用来给视频avpaket包添加头信息 4.打开2个输出文件音频 视频 5.循环读取视频文件并将音视频分别写入文件 注意音频需要手动添加头信息没有提供aac的adts自动添加的过滤器 【mp4_demuxer.cpp】 #include stdio.h
extern C
{
#include libavformat/avformat.h
}/* 打印编码器支持该采样率并查找指定采样率下标 */
static int find_sample_rate_index(const AVCodec* codec, int sample_rate)
{const int* p codec-supported_samplerates;int sample_rate_index -1; //支持的分辨率下标int count 0;while (*p ! 0) {// 0作为退出条件比如libfdk-aacenc.c的aac_sample_ratesprintf(%s 支持采样率: %dhz 对应下标%d\n, codec-name, *p, count);if (*p sample_rate)sample_rate_index count;p;count;}return sample_rate_index;
}/// summary
/// 给aac音频数据添加adts头
/// /summary
/// param nameheaderadts数组/param
/// param namesample_rate采样率/param
/// param namechannals通道数/param
/// param nameprfile音频编码器配置文件FF_PROFILE_AAC_LOW 定义在 avcodec.h/param
/// param namelen音频包长度/param
void addHeader(char header[], int sample_rate, int channals, int prfile, int len)
{uint8_t sampleIndex 0; switch (sample_rate) {case 96000: sampleIndex 0; break;case 88200: sampleIndex 1; break;case 64000: sampleIndex 2; break;case 48000: sampleIndex 3; break;case 44100: sampleIndex 4; break;case 32000: sampleIndex 5; break;case 24000: sampleIndex 6; break;case 22050: sampleIndex 7; break;case 16000: sampleIndex 8; break;case 12000: sampleIndex 9; break;case 11025: sampleIndex 10; break;case 8000: sampleIndex 11; break;case 7350: sampleIndex 12; break;default: sampleIndex 4; break;}uint8_t audioType 2; //AAC LCuint8_t channelConfig 2; //双通道len 7;//0,1是固定的header[0] (uint8_t)0xff; //syncword:0xfff 高8bitsheader[1] (uint8_t)0xf0; //syncword:0xfff 低4bitsheader[1] | (0 3); //MPEG Version:0 for MPEG-4,1 for MPEG-2 1bitheader[1] | (0 1); //Layer:0 2bits header[1] | 1; //protection absent:1 1bit//根据aac类型,采样率,通道数来配置header[2] (audioType - 1) 6; //profile:audio_object_type - 1 2bitsheader[2] | (sampleIndex 0x0f) 2; //sampling frequency index:sampling_frequency_index 4bits header[2] | (0 1); //private bit:0 1bitheader[2] | (channelConfig 0x04) 2; //channel configuration:channel_config 高1bit//根据通道数数据长度来配置header[3] (channelConfig 0x03) 6; //channel configuration:channel_config 低2bitsheader[3] | (0 5); //original0 1bitheader[3] | (0 4); //home0 1bitheader[3] | (0 3); //copyright id bit0 1bit header[3] | (0 2); //copyright id start0 1bitheader[3] | ((len 0x1800) 11); //frame lengthvalue 高2bits//根据数据长度来配置header[4] (uint8_t)((len 0x7f8) 3); //frame length:value 中间8bitsheader[5] (uint8_t)((len 0x7) 5); //frame length:value 低3bitsheader[5] | (uint8_t)0x1f; //buffer fullness:0x7ff 高5bitsheader[6] (uint8_t)0xfc;
}int main() {AVFormatContext* ifmt_ctx NULL;AVPacket pkt;int ret;unsigned int i;int videoindex -1, audioindex -1;const char* in_filename test.mp4;const char* out_filename_v test1.h264;const char* out_filename_a test1.aac;if ((ret avformat_open_input(ifmt_ctx, in_filename, 0, 0)) 0) {printf(Could not open input file.);return -1;}if ((ret avformat_find_stream_info(ifmt_ctx, 0)) 0) {printf(Failed to retrieve input stream information);return -1;}videoindex -1;for (i 0; i ifmt_ctx-nb_streams; i) { //nb_streams视音频流的个数if (ifmt_ctx-streams[i]-codecpar-codec_type AVMEDIA_TYPE_VIDEO)videoindex i;else if (ifmt_ctx-streams[i]-codecpar-codec_type AVMEDIA_TYPE_AUDIO)audioindex i;}printf(\nInput Video\n);av_dump_format(ifmt_ctx, 0, in_filename, 0); // 打印信息printf(\n\n);FILE* fp_audio fopen(out_filename_a, wb);FILE* fp_video fopen(out_filename_v, wb);AVBSFContext* bsf_ctx NULL;const AVBitStreamFilter* pfilter av_bsf_get_by_name(h264_mp4toannexb);if (pfilter NULL) {printf(Get bsf failed!\n);}if ((ret av_bsf_alloc(pfilter, bsf_ctx)) ! 0) {printf(Alloc bsf failed!\n);}ret avcodec_parameters_copy(bsf_ctx-par_in, ifmt_ctx-streams[videoindex]-codecpar);if (ret 0) {printf(Set Codec failed!\n);}ret av_bsf_init(bsf_ctx);if (ret 0) {printf(Init bsf failed!\n);}//这里遍历音频编码器打印支持的采样率并找到当前音频采样率所在的下表用于后面添加adts头//本程序并没有使用只是测试如果为了程序健壮性可以采用此方式const AVCodec* codec nullptr;codec avcodec_find_encoder(ifmt_ctx-streams[audioindex]-codecpar-codec_id);int sample_rate_index find_sample_rate_index(codec, ifmt_ctx-streams[audioindex]-codecpar-sample_rate);printf(分辨率数组下表%d\n, sample_rate_index);while (av_read_frame(ifmt_ctx, pkt) 0) {if (pkt.stream_index videoindex) {av_bsf_send_packet(bsf_ctx, pkt);while (true){ret av_bsf_receive_packet(bsf_ctx, pkt);if (ret AVERROR(EAGAIN) || ret AVERROR_EOF)break;else if (ret 0) {printf(Receive Pkt failed!\n);break;}printf(Write Video Packet. size:%d\tpts:%ld\n, pkt.size, pkt.pts);fwrite(pkt.data, 1, pkt.size, fp_video);}}else if (pkt.stream_index audioindex) {printf(Write Audio Packet. size:%d\tpts:%ld\n, pkt.size, pkt.pts);char adts[7] { 0 };addHeader(adts, ifmt_ctx-streams[audioindex]-codecpar-sample_rate, ifmt_ctx-streams[audioindex]-codecpar-channels, ifmt_ctx-streams[audioindex]-codecpar-profile,pkt.size);fwrite(adts, 1, 7, fp_audio);fwrite(pkt.data, 1, pkt.size, fp_audio);}av_packet_unref(pkt);}av_bsf_free(bsf_ctx);fclose(fp_video);fclose(fp_audio);avformat_close_input(ifmt_ctx);return 0;if (ifmt_ctx)avformat_close_input(ifmt_ctx);if (fp_audio)fclose(fp_audio);if (fp_video)fclose(fp_video);if (bsf_ctx)av_bsf_free(bsf_ctx);return -1;
} 【Makefile】 CROSS_COMPILE aarch64-himix200-linux-CC $(CROSS_COMPILE)g
AR $(CROSS_COMPILE)ar
STRIP $(CROSS_COMPILE)stripCFLAGS -Wall -O2 -I../../source/mp4Lib/include
LIBS -L../../source/mp4Lib/lib -lpthread
LIBS -lavformat -lavcodec -lavdevice -lavutil -lavfilter -lswscale -lswresample -lzSRCS $(wildcard *.cpp)
OBJS $(SRCS:%.cpp%.o)
DEPS $(SRCS:%.cpp%.d)
TARGET mp4demuxerall:$(TARGET)-include $(DEPS)%.o:%.cpp$(CC) $(CFLAGS) -c -o $ $%.d:%.cset -e; rm -f $; \$(CC) -MM $(CFLAGS) $ $.$$$$; \sed s,\($*\)\.o[ :]*,\1.o $ : ,g $.$$$$ $; \rm -f $.$$$$$(TARGET):$(OBJS)$(CC) -o $ $^ $(LIBS)$(STRIP) $ .PHONY:cleanclean:rm -fr $(TARGET) $(OBJS) $(DEPS)
