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• ffmpeg encode video with incorrect output mediainfo encoding settings

  24 août 2021, par Foong

  I've been trying to do batch encode videos to H265 format. I am using media-autobuild_suite to build ffmpeg and have already updating ffmpeg to the latest version.

  


  ffmpeg version N-103367-g5ddb4b6a1b-g88b3e31562+1 Copyright (c) 2000-2021 the FFmpeg developers
built with gcc 10.3.0 (Rev5, Built by MSYS2 project)
configuration:  --pkg-config=pkgconf --cc='ccache gcc' --cxx='ccache g++' --ld='ccache g++' --disable-autodetect --enable-amf --enable-bzlib --enable-cuda --enable-cuvid --enable-d3d11va --enable-dxva2 --enable-iconv --enable-lzma --enable-nvenc --enable-schannel --enable-zlib --enable-sdl2 --enable-ffnvcodec --enable-nvdec --enable-cuda-llvm --enable-gmp --enable-libmp3lame --enable-libopus --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libdav1d --enable-libaom --disable-debug --enable-libfdk-aac --extra-libs=-liconv --enable-gpl --enable-version3 --enable-nonfree
libavutil      57.  4.101 / 57.  4.101
libavcodec     59.  5.101 / 59.  5.101
libavformat    59.  4.102 / 59.  4.102
libavdevice    59.  0.101 / 59.  0.101
libavfilter     8.  3.100 /  8.  3.100
libswscale      6.  0.100 /  6.  0.100
libswresample   4.  0.100 /  4.  0.100
libpostproc    56.  0.100 / 56.  0.100


  


  However, the Writing library and Encoding settings output is incorrect. Before update ffmpeg doesn't have this issue. I wonder what have been missing that causing this issue.

  


  encoding CLI :

  


  ffmpeg -y -hide_banner -loglevel error -stats -hwaccel dxva2 -i "input.mkv" -c:v libx265 -vsync cfr -pix_fmt yuv420p10le -preset fast -tune animation -x265-params ctu=32:min-cu-size=8:max-tu-size=16:tu-intra-depth=2:tu-inter-depth=2:me=1:subme=3:merange=44:max-merge=2:keyint=250:min-keyint=23:rc-lookahead=60:lookahead-slices=6:bframes=6:bframe-bias=0:b-adapt=2:ref=6:limit-refs=3:limit-tu=1:aq-mode=3:aq-strength=0.6:rd=3:psy-rd=1.00:psy-rdoq=1.50:rdoq-level=1:deblock=-1,-1:crf=21.0:qblur=0.50:qcomp=0.60:qpmin=0:qpmax=51:frame-threads=1:strong-intra-smoothing=1:no-lossless=1:no-cu-lossless=1:constrained-intra=1:no-fast-intra=1:no-open-gop=1:no-temporal-layers=1:no-limit-modes=1:weightp=1:no-weightb=1:no-analyze-src-pics=1:no-rd-refine=1:signhide=1:sao=1:no-sao-non-deblock=1:b-pyramid=1:no-cutree=1:no-intra-refresh=1:no-amp=1:temporal-mvp=1:no-early-skip=1:no-tskip=1:no-tskip-fast=1:no-deblock=1:no-b-intra=1:no-splitrd-skip=1:no-strict-cbr=1:no-rc-grain=1:no-const-vbv=1:no-opt-qp-pps=1:no-opt-ref-list-length-pps=1:no-multi-pass-opt-rps=1:no-opt-cu-delta-qp=1:no-hdr=1:no-hdr-opt=1:no-dhdr10-opt=1:no-idr-recovery-sei=1:no-limit-sao=1:no-lowpass-dct=1:no-dynamic-refine=1:no-single-sei=1 -c:a libfdk_aac -vf "fps=fps=29.970,setdar=16/9,scale=960:540:flags=lanczos" -map 0:v:? -map 0:a:? -map_metadata:g -1 -map_chapters 0 "output.mkv"


  


  Input video info :

  


  Video
ID                          : 1
Format                      : AVC
Format/Info                 : Advanced Video Codec
Format profile              : High@L3
Format settings             : CABAC / 5 Ref Frames
Format settings, CABAC      : Yes
Format settings, Reference  : 5 frames
Codec ID                    : V_MPEG4/ISO/AVC
Bit rate                    : 1 595 kb/s
Nominal bit rate            : 2 030 kb/s
Width                       : 720 pixels
Height                      : 480 pixels
Display aspect ratio        : 16:9
Original display aspect rat : 3:2
Frame rate mode             : Variable
Original frame rate         : 29.970 FPS
Color space                 : YUV
Chroma subsampling          : 4:2:0
Bit depth                   : 8 bits
Scan type                   : Progressive
Bits/(Pixel*Frame)          : 0.196
Writing library             : x264 core 66 r1115M 11863ac
Encoding settings           : cabac=1 / ref=5 / deblock=1:1:1 / analyse=0x3:0x133 / me=esa / subme=7 / psy_rd=1.0:0.0 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=2 / deadzone=21,11 / chroma_qp_offset=-2 / threads=1 / nr=0 / decimate=0 / mbaff=0 / bframes=1 / b_pyramid=0 / b_adapt=1 / b_bias=0 / direct=3 / wpredb=1 / keyint=250 / keyint_min=25 / scenecut=40 / rc=2pass / bitrate=2030 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / ip_ratio=1.40 / pb_ratio=1.30 / aq=1:1.00
Default                     : Yes
Forced                      : No


  


  Output video info :

  


  Video
ID                          : 1
Format                      : HEVC
Format/Info                 : High Efficiency Video Coding
Format profile              : Main 10@L3.1@Main
Codec ID                    : V_MPEGH/ISO/HEVC
Duration                    : 23 min 29 s
Width                       : 960 pixels
Height                      : 540 pixels
Display aspect ratio        : 16:9
Frame rate mode             : Constant
Frame rate                  : 29.970 (29970/1000) FPS
Color space                 : YUV
Chroma subsampling          : 4:2:0
Bit depth                   : 10 bits
Writing library             : Lavc59.5.100 libx265
Encoding settings           : cabac=1 / ref=5 / deblock=1:1:1 / analyse=0x3:0x133 / me=esa / subme=7 / psy_rd=1.0:0.0 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / cqm=2 / deadzone=21,11 / chroma_qp_offset=-2 / threads=1 / nr=0 / decimate=0 / mbaff=0 / bframes=1 / b_pyramid=0 / b_adapt=1 / b_bias=0 / direct=3 / wpredb=1 / keyint=250 / keyint_min=25 / scenecut=40 / rc=2pass / bitrate=2030 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / ip_ratio=1.40 / pb_ratio=1.30 / aq=1:1.00
Default                     : Yes
Forced                      : No
Color range                 : Limited


  


  Expecting (from previous encoded videos) :

  


  Video
ID                          : 1
Format                      : HEVC
Format/Info                 : High Efficiency Video Coding
Format profile              : Main 10@L3.1@Main
Codec ID                    : V_MPEGH/ISO/HEVC
Duration                    : 24 min 37 s
Bit rate                    : 833 kb/s
Width                       : 960 pixels
Height                      : 720 pixels
Display aspect ratio        : 4:3
Frame rate mode             : Constant
Frame rate                  : 23.976 (23976/1000) FPS
Color space                 : YUV
Chroma subsampling          : 4:2:0
Bit depth                   : 10 bits
Bits/(Pixel*Frame)          : 0.050
Stream size                 : 147 MiB
Title                       : HEVC
Writing library             : x265 3.4+28-419182243:[Windows][GCC 10.2.0][64 bit] 10bit
Encoding settings           : cpuid=1111039 / frame-threads=3 / numa-pools=12 / wpp / no-pmode / no-pme / no-psnr / no-ssim / log-level=2 / input-csp=1 / input-res=960x720 / interlace=0 / total-frames=0 / level-idc=0 / high-tier=1 / uhd-bd=0 / ref=5 / no-allow-non-conformance / no-repeat-headers / annexb / no-aud / no-hrd / info / hash=0 / no-temporal-layers / no-open-gop / min-keyint=1 / keyint=360 / gop-lookahead=0 / bframes=4 / b-adapt=2 / b-pyramid / bframe-bias=0 / rc-lookahead=20 / lookahead-slices=4 / scenecut=40 / hist-scenecut=0 / radl=0 / no-splice / no-intra-refresh / ctu=64 / min-cu-size=8 / no-rect / no-amp / max-tu-size=32 / tu-inter-depth=1 / tu-intra-depth=1 / limit-tu=0 / rdoq-level=0 / dynamic-rd=0.00 / no-ssim-rd / signhide / no-tskip / nr-intra=0 / nr-inter=0 / no-constrained-intra / strong-intra-smoothing / max-merge=2 / limit-refs=3 / no-limit-modes / me=1 / subme=3 / merange=16 / temporal-mvp / no-frame-dup / no-hme / weightp / no-weightb / no-analyze-src-pics / no-deblock / sao / no-sao-non-deblock / rd=3 / selective-sao=4 / no-early-skip / rskip / no-fast-intra / no-tskip-fast / no-cu-lossless / no-b-intra / no-splitrd-skip / rdpenalty=0 / psy-rd=0.20 / psy-rdoq=0.00 / no-rd-refine / no-lossless / cbqpoffs=0 / crqpoffs=0 / rc=crf / crf=26.0 / qcomp=0.60 / qpstep=4 / stats-write=0 / stats-read=0 / ipratio=1.40 / pbratio=1.00 / aq-mode=0 / aq-strength=0.00 / no-cutree / zone-count=0 / no-strict-cbr / qg-size=64 / no-rc-grain / qpmax=51 / qpmin=0 / no-const-vbv / sar=1 / overscan=0 / videoformat=5 / range=0 / colorprim=2 / transfer=2 / colormatrix=2 / chromaloc=0 / display-window=0 / cll=0,0 / min-luma=0 / max-luma=1023 / log2-max-poc-lsb=8 / vui-timing-info / vui-hrd-info / slices=1 / no-opt-qp-pps / no-opt-ref-list-length-pps / no-multi-pass-opt-rps / scenecut-bias=0.05 / hist-threshold=0.03 / no-opt-cu-delta-qp / no-aq-motion / no-hdr10 / no-hdr10-opt / no-dhdr10-opt / no-idr-recovery-sei / analysis-reuse-level=0 / analysis-save-reuse-level=0 / analysis-load-reuse-level=0 / scale-factor=0 / refine-intra=0 / refine-inter=0 / refine-mv=1 / refine-ctu-distortion=0 / no-limit-sao / ctu-info=0 / no-lowpass-dct / refine-analysis-type=0 / copy-pic=1 / max-ausize-factor=1.0 / no-dynamic-refine / no-single-sei / no-hevc-aq / no-svt / no-field / qp-adaptation-range=1.00 / no-scenecut-aware-qpconformance-window-offsets / right=0 / bottom=0 / decoder-max-rate=0 / no-vbv-live-multi-pass
Language                    : English
Default                     : Yes
Forced                      : No
Color range                 : Limited


  


  I have tried with simplest ffmpeg from official wedsite and encoding cli but the output still same.

  


  ffmpeg -i "input.mkv" -c:v libx265 "output.mkv"


  


• How to reparse video with stable "overall bit rate" ? (FFmpeg)

  20 février 2018, par user3360601

  I have such code below :

  #include 
  
  #include 
  
  #include 
  
  
  
  extern "C"
  
  {
  
  #include <libavcodec></libavcodec>avcodec.h>
  
  #include <libavformat></libavformat>avformat.h>
  
  #include <libavfilter></libavfilter>buffersink.h>
  
  #include <libavfilter></libavfilter>buffersrc.h>
  
  #include <libavutil></libavutil>opt.h>
  
  #include <libavutil></libavutil>pixdesc.h>
  
  }
  
  
  
  static AVFormatContext *ifmt_ctx;
  
  static AVFormatContext *ofmt_ctx;
  
  
  
  typedef struct StreamContext {
  
      AVCodecContext *dec_ctx;
  
      AVCodecContext *enc_ctx;
  
  } StreamContext;
  
  static StreamContext *stream_ctx;
  
  
  
  static int open_input_file(const char *filename)
  
  {
  
      int ret;
  
      unsigned int i;
  
  
  
      ifmt_ctx = NULL;
  
      if ((ret = avformat_open_input(&amp;ifmt_ctx, filename, NULL, NULL)) &lt; 0) {
  
          av_log(NULL, AV_LOG_ERROR, "Cannot open input file\n");
  
          return ret;
  
      }
  
  
  
      if ((ret = avformat_find_stream_info(ifmt_ctx, NULL)) &lt; 0) {
  
          av_log(NULL, AV_LOG_ERROR, "Cannot find stream information\n");
  
          return ret;
  
      }
  
  
  
      stream_ctx = (StreamContext *) av_mallocz_array(ifmt_ctx->nb_streams, sizeof(*stream_ctx));
  
      if (!stream_ctx)
  
          return AVERROR(ENOMEM);
  
  
  
      for (i = 0; i &lt; ifmt_ctx->nb_streams; i++) {
  
          AVStream *stream = ifmt_ctx->streams[i];
  
          AVCodec *dec = avcodec_find_decoder(stream->codecpar->codec_id);
  
          AVCodecContext *codec_ctx;
  
          if (!dec) {
  
              av_log(NULL, AV_LOG_ERROR, "Failed to find decoder for stream #%u\n", i);
  
              return AVERROR_DECODER_NOT_FOUND;
  
          }
  
          codec_ctx = avcodec_alloc_context3(dec);
  
          if (!codec_ctx) {
  
              av_log(NULL, AV_LOG_ERROR, "Failed to allocate the decoder context for stream #%u\n", i);
  
              return AVERROR(ENOMEM);
  
          }
  
          ret = avcodec_parameters_to_context(codec_ctx, stream->codecpar);
  
          if (ret &lt; 0) {
  
              av_log(NULL, AV_LOG_ERROR, "Failed to copy decoder parameters to input decoder context "
  
                  "for stream #%u\n", i);
  
              return ret;
  
          }
  
          /* Reencode video &amp; audio and remux subtitles etc. */
  
          if (codec_ctx->codec_type == AVMEDIA_TYPE_VIDEO
  
              || codec_ctx->codec_type == AVMEDIA_TYPE_AUDIO) {
  
              if (codec_ctx->codec_type == AVMEDIA_TYPE_VIDEO)
  
                  codec_ctx->framerate = av_guess_frame_rate(ifmt_ctx, stream, NULL);
  
              /* Open decoder */
  
              ret = avcodec_open2(codec_ctx, dec, NULL);
  
              if (ret &lt; 0) {
  
                  av_log(NULL, AV_LOG_ERROR, "Failed to open decoder for stream #%u\n", i);
  
                  return ret;
  
              }
  
          }
  
          stream_ctx[i].dec_ctx = codec_ctx;
  
      }
  
  
  
      av_dump_format(ifmt_ctx, 0, filename, 0);
  
      return 0;
  
  }
  
  
  
  static int open_output_file(const char *filename)
  
  {
  
      AVStream *out_stream;
  
      AVStream *in_stream;
  
      AVCodecContext *dec_ctx, *enc_ctx;
  
      AVCodec *encoder;
  
      int ret;
  
      unsigned int i;
  
  
  
      ofmt_ctx = NULL;
  
      avformat_alloc_output_context2(&amp;ofmt_ctx, NULL, NULL, filename);
  
      if (!ofmt_ctx) {
  
          av_log(NULL, AV_LOG_ERROR, "Could not create output context\n");
  
          return AVERROR_UNKNOWN;
  
      }
  
  
  
  
  
      for (i = 0; i &lt; ifmt_ctx->nb_streams; i++) {
  
          out_stream = avformat_new_stream(ofmt_ctx, NULL);
  
          if (!out_stream) {
  
              av_log(NULL, AV_LOG_ERROR, "Failed allocating output stream\n");
  
              return AVERROR_UNKNOWN;
  
          }
  
  
  
          in_stream = ifmt_ctx->streams[i];
  
          dec_ctx = stream_ctx[i].dec_ctx;
  
  
  
          //ofmt_ctx->bit_rate = ifmt_ctx->bit_rate;
  
          ofmt_ctx->duration = ifmt_ctx->duration;
  
  
  
          if (dec_ctx->codec_type == AVMEDIA_TYPE_VIDEO
  
              || dec_ctx->codec_type == AVMEDIA_TYPE_AUDIO) {
  
              /* in this example, we choose transcoding to same codec */
  
              encoder = avcodec_find_encoder(dec_ctx->codec_id);
  
              if (!encoder) {
  
                  av_log(NULL, AV_LOG_FATAL, "Necessary encoder not found\n");
  
                  return AVERROR_INVALIDDATA;
  
              }
  
              enc_ctx = avcodec_alloc_context3(encoder);
  
              if (!enc_ctx) {
  
                  av_log(NULL, AV_LOG_FATAL, "Failed to allocate the encoder context\n");
  
                  return AVERROR(ENOMEM);
  
              }
  
  
  
              /* In this example, we transcode to same properties (picture size,
  
              * sample rate etc.). These properties can be changed for output
  
              * streams easily using filters */
  
              if (dec_ctx->codec_type == AVMEDIA_TYPE_VIDEO) {
  
                  enc_ctx->gop_size = dec_ctx->gop_size;
  
                  enc_ctx->bit_rate = dec_ctx->bit_rate;
  
                  enc_ctx->height = dec_ctx->height;
  
                  enc_ctx->width = dec_ctx->width;
  
                  enc_ctx->sample_aspect_ratio = dec_ctx->sample_aspect_ratio;
  
                  /* take first format from list of supported formats */
  
                  if (encoder->pix_fmts)
  
                      enc_ctx->pix_fmt = encoder->pix_fmts[0];
  
                  else
  
                      enc_ctx->pix_fmt = dec_ctx->pix_fmt;
  
                  /* video time_base can be set to whatever is handy and supported by encoder */
  
                  enc_ctx->time_base = av_inv_q(dec_ctx->framerate);
  
                  enc_ctx->framerate = av_guess_frame_rate(ifmt_ctx, in_stream, NULL);
  
              }
  
              else {
  
                  enc_ctx->gop_size = dec_ctx->gop_size;
  
                  enc_ctx->bit_rate = dec_ctx->bit_rate;
  
                  enc_ctx->sample_rate = dec_ctx->sample_rate;
  
                  enc_ctx->channel_layout = dec_ctx->channel_layout;
  
                  enc_ctx->channels = av_get_channel_layout_nb_channels(enc_ctx->channel_layout);
  
                  /* take first format from list of supported formats */
  
                  enc_ctx->sample_fmt = encoder->sample_fmts[0];
  
                  //enc_ctx->time_base = (AVRational){ 1, enc_ctx->sample_rate };
  
                  enc_ctx->time_base.num = 1;
  
                  enc_ctx->time_base.den = enc_ctx->sample_rate;
  
  
  
                  enc_ctx->framerate = av_guess_frame_rate(ifmt_ctx, in_stream, NULL);
  
              }
  
  
  
              /* Third parameter can be used to pass settings to encoder */
  
              ret = avcodec_open2(enc_ctx, encoder, NULL);
  
              if (ret &lt; 0) {
  
                  av_log(NULL, AV_LOG_ERROR, "Cannot open video encoder for stream #%u\n", i);
  
                  return ret;
  
              }
  
              ret = avcodec_parameters_from_context(out_stream->codecpar, enc_ctx);
  
              if (ret &lt; 0) {
  
                  av_log(NULL, AV_LOG_ERROR, "Failed to copy encoder parameters to output stream #%u\n", i);
  
                  return ret;
  
              }
  
              if (ofmt_ctx->oformat->flags &amp; AVFMT_GLOBALHEADER)
  
                  enc_ctx->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
  
  
  
              out_stream->time_base = enc_ctx->time_base;
  
              stream_ctx[i].enc_ctx = enc_ctx;
  
          }
  
          else if (dec_ctx->codec_type == AVMEDIA_TYPE_UNKNOWN) {
  
              av_log(NULL, AV_LOG_FATAL, "Elementary stream #%d is of unknown type, cannot proceed\n", i);
  
              return AVERROR_INVALIDDATA;
  
          }
  
          else {
  
              /* if this stream must be remuxed */
  
              ret = avcodec_parameters_copy(out_stream->codecpar, in_stream->codecpar);
  
              if (ret &lt; 0) {
  
                  av_log(NULL, AV_LOG_ERROR, "Copying parameters for stream #%u failed\n", i);
  
                  return ret;
  
              }
  
              out_stream->time_base = in_stream->time_base;
  
          }
  
  
  
      }
  
      av_dump_format(ofmt_ctx, 0, filename, 1);
  
  
  
      if (!(ofmt_ctx->oformat->flags &amp; AVFMT_NOFILE)) {
  
          ret = avio_open(&amp;ofmt_ctx->pb, filename, AVIO_FLAG_WRITE);
  
          if (ret &lt; 0) {
  
              av_log(NULL, AV_LOG_ERROR, "Could not open output file '%s'", filename);
  
              return ret;
  
          }
  
      }
  
  
  
      /* init muxer, write output file header */
  
      ret = avformat_write_header(ofmt_ctx, NULL);
  
      if (ret &lt; 0) {
  
          av_log(NULL, AV_LOG_ERROR, "Error occurred when opening output file\n");
  
          return ret;
  
      }
  
  
  
      return 0;
  
  }
  
  
  
  int main(int argc, char **argv)
  
  {
  
      int ret;
  
      AVPacket packet = {0};
  
      packet.data = NULL;
  
      packet.size = 0 ;
  
      AVFrame *frame = NULL;
  
      enum AVMediaType type;
  
      unsigned int stream_index;
  
      unsigned int i;
  
      int got_frame;
  
      int(*dec_func)(AVCodecContext *, AVFrame *, int *, const AVPacket *);
  
  
  
      if (argc != 3) {
  
          av_log(NULL, AV_LOG_ERROR, "Usage: %s <input file="file" /> <output file="file">\n", argv[0]);
  
          return 1;
  
      }
  
  
  
      av_register_all();
  
      avfilter_register_all();
  
  
  
      if ((ret = open_input_file(argv[1])) &lt; 0)
  
          goto end;
  
      if ((ret = open_output_file(argv[2])) &lt; 0)
  
          goto end;
  
  
  
      /* read all packets */
  
      while (1) {
  
          if ((ret = av_read_frame(ifmt_ctx, &amp;packet)) &lt; 0)
  
              break;
  
          stream_index = packet.stream_index;
  
          type = ifmt_ctx->streams[packet.stream_index]->codecpar->codec_type;
  
          av_log(NULL, AV_LOG_DEBUG, "Demuxer gave frame of stream_index %u\n", stream_index);
  
  
  
          /* remux this frame without reencoding */
  
          av_packet_rescale_ts(&amp;packet,
  
              ifmt_ctx->streams[stream_index]->time_base,
  
              ofmt_ctx->streams[stream_index]->time_base);
  
  
  
          ret = av_interleaved_write_frame(ofmt_ctx, &amp;packet);
  
          if (ret &lt; 0)
  
              goto end;
  
  
  
          av_packet_unref(&amp;packet);
  
      }
  
  
  
      av_write_trailer(ofmt_ctx);
  
  end:
  
      av_packet_unref(&amp;packet);
  
      av_frame_free(&amp;frame);
  
      for (i = 0; i &lt; ifmt_ctx->nb_streams; i++) {
  
          avcodec_free_context(&amp;stream_ctx[i].dec_ctx);
  
          if (ofmt_ctx &amp;&amp; ofmt_ctx->nb_streams > i &amp;&amp; ofmt_ctx->streams[i] &amp;&amp; stream_ctx[i].enc_ctx)
  
              avcodec_free_context(&amp;stream_ctx[i].enc_ctx);
  
      }
  
      av_free(stream_ctx);
  
      avformat_close_input(&amp;ifmt_ctx);
  
      if (ofmt_ctx &amp;&amp; !(ofmt_ctx->oformat->flags &amp; AVFMT_NOFILE))
  
          avio_closep(&amp;ofmt_ctx->pb);
  
      avformat_free_context(ofmt_ctx);
  
  
  
      return ret ? 1 : 0;
  
  }
  
  </output>

  This is a little bit changed code from official example of using ffmpeg called transcoding.c

  I only read packets from one stream and write them to another stream. It works fine.

  Proof below.
  

  then I add to main a condition. If it is a packet with video frame, I will decode it, then encode and write to another stream. No other actions with frame.

  My addition code below :

  static int encode_write_frame(AVFrame *filt_frame, unsigned int stream_index, int *got_frame) {
  
      int ret;
  
      int got_frame_local;
  
      AVPacket enc_pkt;
  
      int(*enc_func)(AVCodecContext *, AVPacket *, const AVFrame *, int *) = avcodec_encode_video2 ;
  
  
  
      if (!got_frame)
  
          got_frame = &got_frame_local;
  
  
  
      av_log(NULL, AV_LOG_INFO, "Encoding frame\n");
  
      /* encode filtered frame */
  
      enc_pkt.data = NULL;
  
      enc_pkt.size = 0;
  
      av_init_packet(&enc_pkt);
  
      ret = enc_func(stream_ctx[stream_index].enc_ctx, &enc_pkt,
  
          filt_frame, got_frame);
  
      if (ret < 0)
  
          return ret;
  
      if (!(*got_frame))
  
          return 0;
  
  
  
      /* prepare packet for muxing */
  
      enc_pkt.stream_index = stream_index;
  
      av_packet_rescale_ts(&enc_pkt,
  
          stream_ctx[stream_index].enc_ctx->time_base,
  
          ofmt_ctx->streams[stream_index]->time_base);
  
  
  
      av_log(NULL, AV_LOG_DEBUG, "Muxing frame\n");
  
      /* mux encoded frame */
  
      ret = av_interleaved_write_frame(ofmt_ctx, &enc_pkt);
  
      return ret;
  
  }
  
  
  
  static int filter_encode_write_frame(AVFrame *frame, unsigned int stream_index)
  
  {
  
      int ret;
  
      av_log(NULL, AV_LOG_INFO, "Pushing decoded frame to filters\n");
  
  
  
      while (1) {
  
          av_log(NULL, AV_LOG_INFO, "Pulling filtered frame from filters\n");
  
  
  
          ret = encode_write_frame(frame, stream_index, NULL);
  
          if (ret < 0)
  
              break;
  
          break;
  
      }
  
  
  
      return ret;
  
  }
  
  
  
  
  
  int main(int argc, char **argv)
  
  {
  
      int ret;
  
      AVPacket packet = {0};
  
      packet.data = NULL;
  
      packet.size = 0 ;
  
      AVFrame *frame = NULL;
  
      enum AVMediaType type;
  
      unsigned int stream_index;
  
      unsigned int i;
  
      int got_frame;
  
      int(*dec_func)(AVCodecContext *, AVFrame *, int *, const AVPacket *);
  
  
  
      if (argc != 3) {
  
          av_log(NULL, AV_LOG_ERROR, "Usage: %s <input file="file" /> <output file="file">\n", argv[0]);
  
          return 1;
  
      }
  
  
  
      av_register_all();
  
      avfilter_register_all();
  
  
  
      if ((ret = open_input_file(argv[1])) &lt; 0)
  
          goto end;
  
      if ((ret = open_output_file(argv[2])) &lt; 0)
  
          goto end;
  
  
  
      /* read all packets */
  
      while (1) {
  
          if ((ret = av_read_frame(ifmt_ctx, &amp;packet)) &lt; 0)
  
              break;
  
          stream_index = packet.stream_index;
  
          type = ifmt_ctx->streams[packet.stream_index]->codecpar->codec_type;
  
          av_log(NULL, AV_LOG_DEBUG, "Demuxer gave frame of stream_index %u\n",
  
              stream_index);
  
  
  
           if (type == AVMEDIA_TYPE_VIDEO)
  
           {
  
               av_log(NULL, AV_LOG_DEBUG, "Going to reencode&amp;filter the frame\n");
  
               frame = av_frame_alloc();
  
               if (!frame) {
  
                   ret = AVERROR(ENOMEM);
  
                   break;
  
               }
  
               av_packet_rescale_ts(&amp;packet,
  
                   ifmt_ctx->streams[stream_index]->time_base,
  
                   stream_ctx[stream_index].dec_ctx->time_base);
  
               dec_func = avcodec_decode_video2;
  
               ret = dec_func(stream_ctx[stream_index].dec_ctx, frame,
  
                   &amp;got_frame, &amp;packet);
  
               if (ret &lt; 0) {
  
                   av_frame_free(&amp;frame);
  
                   av_log(NULL, AV_LOG_ERROR, "Decoding failed\n");
  
                   break;
  
               }
  
  
  
               if (got_frame) {
  
                   frame->pts = frame->best_effort_timestamp;
  
                   ret = filter_encode_write_frame(frame, stream_index);
  
                   av_frame_free(&amp;frame);
  
                   if (ret &lt; 0)
  
                       goto end;
  
               }
  
               else {
  
                   av_frame_free(&amp;frame);
  
               }
  
           }
  
           else 
  
          {
  
              /* remux this frame without reencoding */
  
              av_packet_rescale_ts(&amp;packet,
  
                  ifmt_ctx->streams[stream_index]->time_base,
  
                  ofmt_ctx->streams[stream_index]->time_base);
  
  
  
              ret = av_interleaved_write_frame(ofmt_ctx, &amp;packet);
  
              if (ret &lt; 0)
  
                  goto end;
  
          }
  
          av_packet_unref(&amp;packet);
  
      }
  
  
  
      av_write_trailer(ofmt_ctx);
  
  end:
  
      av_packet_unref(&amp;packet);
  
      av_frame_free(&amp;frame);
  
      for (i = 0; i &lt; ifmt_ctx->nb_streams; i++) {
  
          avcodec_free_context(&amp;stream_ctx[i].dec_ctx);
  
          if (ofmt_ctx &amp;&amp; ofmt_ctx->nb_streams > i &amp;&amp; ofmt_ctx->streams[i] &amp;&amp; stream_ctx[i].enc_ctx)
  
              avcodec_free_context(&amp;stream_ctx[i].enc_ctx);
  
      }
  
      av_free(stream_ctx);
  
      avformat_close_input(&amp;ifmt_ctx);
  
      if (ofmt_ctx &amp;&amp; !(ofmt_ctx->oformat->flags &amp; AVFMT_NOFILE))
  
          avio_closep(&amp;ofmt_ctx->pb);
  
      avformat_free_context(ofmt_ctx);
  
  
  
      return ret ? 1 : 0;
  
  }
  
  </output>

  And the result is different.

  For a test I took a SampleVideo_1280x720_1mb.flv.
  It has

  File size : 1.00 MiB
  Overall bit rate : 1 630 kb/s

  After my decode/encode actions the result became :

  File size : 1.23 MiB
  Overall bit rate : 2 005 kb/s

  Other parameters (video bit rate, audio bit rate, etc) are the same.
  

  What am I doing wrong ? How to control overall bit rate ? I suppose, something wrong with encoder/decoder, but what ?

  UPD :
  I get that when in function open_input_file I write

  if (codec_ctx->codec_type == AVMEDIA_TYPE_VIDEO)
  
  {
  
       codec_ctx->framerate = av_guess_frame_rate(ifmt_ctx, stream, NULL);
  
  }

  I get what I get (bigger size and bit rate).

  And when in this function I write

  if (codec_ctx->codec_type == AVMEDIA_TYPE_VIDEO)
  
  {
  
      codec_ctx = ifmt_ctx->streams[i]->codec;
  
  }

  I get smaller size and bit rate.

  File size : 900 KiB
  Overall bit rate : 1 429 kb/s

  But how to get the exactly size and frame rate as in the original file ?

• Revision 34537 : un pour englober le contenu principal de ...

  17 janvier 2010, par cedric@… — Log

  un pour englober le contenu principal de chaque objet. Permet de cibler le debut ou la fin du contenu principal, ou, en passant par le parent, la fin du contenu.