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• In using FFmpeg SDK, the mp4 file encoded with HEVC(x265) codec not playing in general player

  26 octobre 2016, par Wiktor Kostus

  Everyone !

  I am going to encode mp4 file (x264 codec) to HEVC(x265) codec using FFmpeg SDK.
  Also, I am going to write the encoded file into .mp4 file container.

  The problem I am facing is that the encoded file is played well in FFplay and VLC player but it isn’t played in general HEVC player.

  I used the general method to encode the codec in FFmpeg SDK. I think I have a mistake to use the avformat_write_header() function. It seems that some parameters to pass AVFormatContext, AVOutputFormat or AVCodecContext for HEVC codec are missing.

  Finally, I would like to know the way to write the HEVC codec into mp4 container. I also would like to know the right parameters related to Context instances for HEVC codec.

  Below is my tiny demo code. (I have skipped the code related to InputStream since I think I have a mistake in OutputStream)

  AVFormatContext* pFormatCtx;
  
  AVOutputFormat* fmt;
  
  AVStream* video_st;
  
  AVCodecContext* pCodecCtx;
  
  
  
  const char* out_file = "output.mp4";
  
  
  
  pFormatCtx = avformat_alloc_context();
  
  fmt = av_guess_format(NULL, out_file, NULL);
  
  pFormatCtx->oformat = fmt;
  
  
  
  if (avio_open(&pFormatCtx->pb, out_file, AVIO_FLAG_READ_WRITE) < 0){
  
      printf("Failed to open output file! \n");
  
      return -1;
  
  }
  
  
  
  video_st = avformat_new_stream(pFormatCtx, 0);
  
  video_st->time_base.num = 1; 
  
  video_st->time_base.den = 25;  
  
  
  
  if (video_st==NULL){
  
      return -1;
  
  }
  
  //Param that must set
  
  pCodecCtx = video_st->codec;
  
  pCodecCtx->codec_id =AV_CODEC_ID_HEVC;
  
  pCodecCtx->codec_id = fmt->video_codec;
  
  pCodecCtx->codec_type = AVMEDIA_TYPE_VIDEO;
  
  pCodecCtx->pix_fmt = PIX_FMT_YUV420P;
  
  pCodecCtx->width = in_w;  
  
  pCodecCtx->height = in_h;
  
  pCodecCtx->time_base.num = 1;  
  
  pCodecCtx->time_base.den = 25;  
  
  pCodecCtx->bit_rate = 400000;  
  
  pCodecCtx->gop_size=250;
  
  pCodecCtx->qmin = 10;
  
  pCodecCtx->qmax = 51;
  
  pCodecCtx->max_b_frames = 1;
  
  
  
  // Set Option
  
  AVDictionary *param = 0;
  
  av_dict_set(&param, "preset", "ultrafast", 0);
  
  av_dict_set(&param, "tune", "zero-latency", 0);
  
  av_dict_set(&param, "x265-params", "crf=25", 0);
  
  
  
  pCodec = avcodec_find_encoder(pCodecCtx->codec_id);
  
  if (!pCodec){
  
      printf("Can not find encoder! \n");
  
      return -1;
  
  }
  
  if (avcodec_open2(pCodecCtx, pCodec,&param) < 0){
  
      printf("Failed to open encoder! \n");
  
      return -1;
  
  }
  
  
  
  //Write File Header
  
  avformat_write_header(pFormatCtx, NULL); <------ I think it takes any error in here.

  Help me what I am doing wrong.

  Thank you for your consider.

• Revision b62ddd5f8b : General code cleanup. Switching from mi_{width, height}_log2 and b_{width, heig

  28 août 2013, par Dmitry Kovalev

  Changed Paths :
   Modify /vp9/decoder/vp9_decodframe.c

  
   Modify /vp9/encoder/vp9_bitstream.c

  
   Modify /vp9/encoder/vp9_encodeframe.c

  
   Modify /vp9/encoder/vp9_rdopt.c

  
  
  General code cleanup.

  Switching from mi_width, height_log2 and b_width, height_log2 to
  num_8x8_blocks_wide, high and num_4x4_blocks_wide, high. Removing
  redundant code, adding const.

  Change-Id : Iaab2207590fd24d0b76999071778d1395dc5cd5d

• What is ffmpeg trying to do when fps is shown gradually decreasing for a given frame ?

  30 mars 2015, par eternalthinker

  I’ve been trying to create an animated overlay over an FLV video, and trying to get the output in MP4 format. I initially used ffmpeg version 1.26. But, as the filters seem to support better options with the latest format, I compiled ffmpeg version 2.61 from source.

  Now the encoding seems to work fine, but the command stays at one point for too long, where it is seen that the fps drops to smaller values, and the ’drop’ value changes accordingly. I used the fps filter to supply fps=25 option, and now the encoding is stuck at the same point, only the drop value remains 0, while fps is shown dropping to smaller values, taking a long time as before.

  

  In the screenshot above, all values remain same, while fps keep dropping to smaller values. After 10fps, it drops by 0.1 and continues past 1, to 0.9 etc. I didn’t wait until it went down further, as the whole thing was taking too much time.

  What can I do to avoid this, and tell ffmpeg to move on with one framerate ? That is, to finish encoding after the 21.45 seconds shown here, and not try to tweak fps or whatever it is trying to do here.

  The full command I am using is this :

  ffmpeg -y -i BaseVideo.flv  -loop 1 -i 1overlay.png  -loop 1 -filter_complex '[1:v] fade=out:20:20:alpha=1:start_time=4:d=3:c=white [V2]; [0:v][V2] overlay, fps=25' -c:v libx264 -strict -2 result.mp4