Recherche avancée

Sur d’autres sites (8160)

• Demuxing a video media file with FFMPEG

  23 février 2016, par MOHW

  After starting this question Extracting the h264 part of a video file (demuxing) I was actually able to figure out that,

  1. When I reverted to an older version of FFMPEG (avcodec-55.dll) as against the avcodec-57.dll I was using earlier, the code worked perfectly without any error and the resultant h264 file played with ffplay.
  2. When I tracked my output when using the avcodec-57.dll version of FFMPEG (most recent version), there was actually an error "Using AVStream.codec.time_base as a timebase hint to the muxer is deprecated. Set AVStream.time_base instead" after the call avformat_write_header(ofmt_ctx_v, NULL) and another one after the call to avformat_write_header(ofmt_ctx_a, NULL). The program continued executing, the audio was fine but the .h264 file wasn’t.

  The output

  Press any key to continue . . .
  
  Press any key to continue . . .
  
  Press any key to continue . . .
  
  Press any key to continue . . .
  
  
  
  ==============Input Video=============
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'sample.mp4':
  
    Metadata:
  
      major_brand     : isom
  
      minor_version   : 512
  
      compatible_brands: isomiso2avc1mp41
  
      title           : 10153755968775490
  
      encoder         : Lavf57.19.100
  
    Duration: 00:01:07.27, start: 0.020021, bitrate: 1058 kb/s
  
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 400x224 [
  
  SAR 199:200 DAR 199:112], 927 kb/s, 15 fps, 15 tbr, 15360 tbn, 30 tbc (default)
  
      Metadata:
  
        handler_name    : VideoHandler
  
      Stream #0:1(eng): Audio: mp3 (mp4a / 0x6134706D), 48000 Hz, stereo, s16p, 12
  
  8 kb/s (default)
  
      Metadata:
  
        handler_name    : SoundHandler
  
  
  
  ==============Output Video============
  
  Output #0, h264, to 'sample.h264':
  
      Stream #0:0: Video: h264 (High), yuv420p, 400x224 [SAR 199:200 DAR 199:112],
  
   q=2-31, 927 kb/s, 30 tbc
  
  
  
  ==============Output Audio============
  
  Output #0, mp3, to 'sample.mp3':
  
      Stream #0:0: Audio: mp3, 48000 Hz, stereo, s16p, 128 kb/s
  
  
  
  ======================================
  
  [h264 @ 00a3ee20] Using AVStream.codec.time_base as a timebase hint to the muxer
  
   is deprecated. Set AVStream.time_base instead.
  
  [mp3 @ 00a4fec0] Using AVStream.codec.time_base as a timebase hint to the muxer
  
  is deprecated. Set AVStream.time_base instead.
  
  Press any key to continue . . .

  The code

  #include 
  
  
  
  #define __STDC_CONSTANT_MACROS
  
  
  
  extern "C"
  
  {
  
      #include "libavformat/avformat.h"
  
  }
  
  
  
  
  
  #define USE_H264BSF 1
  
  
  
  int main()
  
  {
  
      AVOutputFormat *ofmt_a = NULL,*ofmt_v = NULL;
  
      AVFormatContext *ifmt_ctx = NULL, *ofmt_ctx_a = NULL, *ofmt_ctx_v = NULL;
  
      AVPacket pkt;
  
      int ret, i;
  
      int videoindex=-1,audioindex=-1;
  
      int frame_index=0;
  
  
  
      const char *in_filename  = "sample.mp4";
  
      const char *out_filename_v = "sample.h264";
  
      const char *out_filename_a = "sample.mp3";
  
  
  
      av_register_all();
  
      //Input
  
      if ((ret = avformat_open_input(&ifmt_ctx, in_filename, 0, 0)) < 0) {
  
          printf( "Could not open input file.");
  
          goto end;
  
      }
  
      if ((ret = avformat_find_stream_info(ifmt_ctx, 0)) < 0) {
  
          printf( "Failed to retrieve input stream information");
  
          goto end;
  
      }
  
  system("pause");
  
  
  
      //Output
  
      avformat_alloc_output_context2(&ofmt_ctx_v, NULL, NULL, out_filename_v);
  
      if (!ofmt_ctx_v) {
  
          printf( "Could not create output context\n");
  
          ret = AVERROR_UNKNOWN;
  
          goto end;
  
      }
  
      ofmt_v = ofmt_ctx_v->oformat;
  
  
  
  system("pause");
  
  
  
      avformat_alloc_output_context2(&ofmt_ctx_a, NULL, NULL, out_filename_a);
  
      if (!ofmt_ctx_a) {
  
          printf( "Could not create output context\n");
  
          ret = AVERROR_UNKNOWN;
  
          goto end;
  
      }
  
      ofmt_a = ofmt_ctx_a->oformat;
  
  system("pause");
  
      for (i = 0; i < ifmt_ctx->nb_streams; i++) {
  
              //Create output AVStream according to input AVStream
  
              AVFormatContext *ofmt_ctx;
  
              AVStream *in_stream = ifmt_ctx->streams[i];
  
              AVStream *out_stream = NULL;
  
  
  
              if(ifmt_ctx->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO){
  
                  videoindex=i;
  
                  out_stream=avformat_new_stream(ofmt_ctx_v, in_stream->codec->codec);
  
                  ofmt_ctx=ofmt_ctx_v;
  
              }else if(ifmt_ctx->streams[i]->codec->codec_type==AVMEDIA_TYPE_AUDIO){
  
                  audioindex=i;
  
                  out_stream=avformat_new_stream(ofmt_ctx_a, in_stream->codec->codec);
  
                  ofmt_ctx=ofmt_ctx_a;
  
              }else{
  
                  break;
  
              }
  
  
  
              if (!out_stream) {
  
                  printf( "Failed allocating output stream\n");
  
                  ret = AVERROR_UNKNOWN;
  
                  goto end;
  
              }
  
              //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;
  
      }
  
  system("pause");
  
      //Dump Format------------------
  
      printf("\n==============Input Video=============\n");
  
      av_dump_format(ifmt_ctx, 0, in_filename, 0);
  
      printf("\n==============Output Video============\n");
  
      av_dump_format(ofmt_ctx_v, 0, out_filename_v, 1);
  
      printf("\n==============Output Audio============\n");
  
      av_dump_format(ofmt_ctx_a, 0, out_filename_a, 1);
  
      printf("\n======================================\n");
  
      //Open output file
  
      if (!(ofmt_v->flags & AVFMT_NOFILE)) {
  
          if (avio_open(&ofmt_ctx_v->pb, out_filename_v, AVIO_FLAG_WRITE) < 0) {
  
              printf( "Could not open output file '%s'", out_filename_v);
  
              goto end;
  
          }
  
      }
  
  
  
      if (!(ofmt_a->flags & AVFMT_NOFILE)) {
  
          if (avio_open(&ofmt_ctx_a->pb, out_filename_a, AVIO_FLAG_WRITE) < 0) {
  
              printf( "Could not open output file '%s'", out_filename_a);
  
              goto end;
  
          }
  
      }
  
  
  
      //Write file header
  
      if (avformat_write_header(ofmt_ctx_v, NULL) < 0) {
  
          printf( "Error occurred when opening video output file\n");
  
          goto end;
  
      }
  
  
  
      if (avformat_write_header(ofmt_ctx_a, NULL) < 0) {
  
          printf( "Error occurred when opening audio output file\n");
  
          goto end;
  
      }
  
      system("pause");
  
  #if USE_H264BSF
  
      AVBitStreamFilterContext* h264bsfc =  av_bitstream_filter_init("h264_mp4toannexb"); 
  
  #endif
  
  
  
      while (1) {
  
          AVFormatContext *ofmt_ctx;
  
          AVStream *in_stream, *out_stream;
  
          //Get an AVPacket
  
          if (av_read_frame(ifmt_ctx, &pkt) < 0)
  
              break;
  
          in_stream  = ifmt_ctx->streams[pkt.stream_index];
  
  
  
  
  
          if(pkt.stream_index==videoindex){
  
              out_stream = ofmt_ctx_v->streams[0];
  
              ofmt_ctx=ofmt_ctx_v;
  
              #if USE_H264BSF
  
                  av_bitstream_filter_filter(h264bsfc, in_stream->codec, NULL, &pkt.data, &pkt.size, pkt.data, pkt.size, 0);
  
              #endif
  
              printf("Write Video Packet. size:%d\tpts:%lld\n",pkt.size,pkt.pts);
  
          }else if(pkt.stream_index==audioindex){
  
              out_stream = ofmt_ctx_a->streams[0];
  
              ofmt_ctx=ofmt_ctx_a;
  
              printf("Write Audio Packet. size:%d\tpts:%lld\n",pkt.size,pkt.pts);
  
          }else{
  
              continue;
  
          }
  
  
  
  
  
          //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=0;
  
          //Write
  
          if (av_interleaved_write_frame(ofmt_ctx, &pkt) < 0) {
  
              printf( "Error muxing packet\n");
  
              break;
  
          }
  
          //printf("Write %8d frames to output file\n", frame_index);
  
          av_free_packet(&pkt);
  
          frame_index++;
  
      }
  
  system("pause");
  
  #if USE_H264BSF
  
      av_bitstream_filter_close(h264bsfc);  
  
  #endif
  
  
  
      //Write file trailer
  
      av_write_trailer(ofmt_ctx_a);
  
      av_write_trailer(ofmt_ctx_v);
  
  end:
  
      avformat_close_input(&ifmt_ctx);
  
      /* close output */
  
      if (ofmt_ctx_a && !(ofmt_a->flags & AVFMT_NOFILE))
  
          avio_close(ofmt_ctx_a->pb);
  
  
  
      if (ofmt_ctx_v && !(ofmt_v->flags & AVFMT_NOFILE))
  
          avio_close(ofmt_ctx_v->pb);
  
  
  
      avformat_free_context(ofmt_ctx_a);
  
      avformat_free_context(ofmt_ctx_v);
  
  
  
      system("pause");
  
      if (ret < 0 && ret != AVERROR_EOF) {
  
          printf( "Error occurred.\n");
  
          return -1;
  
      }
  
  
  
      return 0;
  
  }

  EDIT 1
  After reading through http://lists.libav.org/pipermail/libav-devel/2014-June/060048.html, I figured what was causing the "Using AVStream.codec.time_base as a timebase hint to the muxer is deprecated. Set AVStream.time_base instead". I fixed it by adding out_stream->time_base = in_stream->time_base; before the call to avformat_write_header. The code now runs without any error ! The h264 file created with the old FFMPEG (avcodec-55.dll) works fine while that created by the recent avcodec-57.dll is still invalid.

• FFMPEG copying Windows Media Audio 9.2

  19 avril 2016, par David GC

  I want to top and tail a wma file with a codec Windows Media Audio 9.2. I know Windows Media Audio 9 Professional encoding is not supported. But I just need to top and tail this audio file.

  I only get an audio file output with codec Windows Media Audio 8.

  ffmpeg -i .\1_encoding.wmv -acodec copy -preset ultrafast .\prueba1.wma

  Is it possible to get an output with Windows Media Audio 9.2 ?

• Exe media file conversion to mp4

  31 mai 2016, par karthikpj

  I have an exe file which is actually a media file which I need to convert to mp4. It contains footage from CCTV cameras.When I open that exe file,a launcher called SecureView is opened and the video can be played inside that player.
  I need to convert that exe to mp4 for viewing it in other normal media players.
  I have used a tool called exe2swf but there was no swf file in it.
  Is there any way to separate that launcher from the video ?