Recherche avancée

Sur d’autres sites (10608)

• avformat/movenc : use enum values directly for colr atom

  31 mars 2020, par Michael Bradshaw

  avformat/movenc : use enum values directly for colr atom
  The switch cases were missing :
    - Primaries : bt470m, film, smpte428, and ebu3213.
  
    - TRCs : gamma22, gamma28, linear, log, log_sqrt, iec61966_2_4, bt1361,
  
      iec61966_2_1, bt2020_10bit, and bt2020_12bit.
  
    - Space : rgb, fcc, ycgco, bt2020_cl, smpte2085, chroma-derived-nc,
  
      chroma-derived-c, and ictcp.
  They also annoyingly remapped the following (which are functionally
  
  equivalent but can be treated differently by clients) :
    - smpte240m primaries to smpte170m.
  
    - smpte170m TRC to bt709.
  
    - bt470bg color space to smpte170m.
  The enum values in FFmpeg are the same values as ITU-T H.273 and
  
  ISO/IEC 23001-8 so we can just use them directly, which is both simpler
  
  and preserves the user intent.
  Signed-off-by : Michael Bradshaw <mjbshaw@google.com>
  

  • [DH] libavformat/movenc.c

• HLS encoded video (ffmpeg) breaks in Safari when segmented via byte-range

  15 juin 2019, par eschie

  Some of my HLS encoded videos via ffmpeg drop the audio when seeking past the buffer. The only way to sync the audio and video up again is to restart the video. What would be causing this ?

  Example Profile :

  bitrate: 4800, profile: 'high', level: '4.1', resolution: 1080, framerate: '24000/1001'

  ffmpeg
  
      '-y' 
  
      '-i' input_file.mov                                                 
  
      '-v' error 
  
      '-map' '0:0'                                                        
  
      '-c:v' libx264                                                  
  
      '-x264opts' f'
  
          keyint=23:                  
  
          min-keyint=23:          
  
          no-scenecut                                                     
  
      '
  
      '-vf' f'scale=-1:1080'
  
      '-preset' 'slow'
  
      '-profile:v' 'high'
  
      '-level' '4.1'
  
      '-b:v' '4800k'
  
      '-maxrate' '4800k'
  
      '-movflags' 'faststart'
  
      '-bufsize' '9600k' 
  
      '-write_tmcd', '0'
  
      '-r' '24000/1001'                                   
  
      output_dir                                                      

  Segmentation CMD :

  FFMPEG 
  
      '-i' output_dir 
  
      '-v' 'error' 
  
      '-acodec' 'copy'
  
      '-vcodec' 'copy'
  
      '-hls_time' '4' #seconds
  
      '-hls_list_size' '0'
  
      '-hls_flags' 'single_file' 
  
      os.path.join(output_dir, f'{run_id}_{bitrate}.m3u8'

  Added : apple’s mediastreamvalidator outputs a few different errors :

  Error: Playlist vs segment duration mismatch
  
  --> Detail:  Segment duration 98.0146, Playlist duration: 4.7968
  
  --> Source:  1559962503399_2200k.m3u8 - 1559962503399_2200k.ts:1746520@0

  Error: Measured peak bitrate compared to master playlist declared value exceeds error tolerance
  
  --> Detail:  Measured: 3182.61 kb/s, Master playlist: 2173.82 kb/s, Error: 46.41%, Combined rendition name: English
  
  --> Source:  ...playlist.m3u8
  
  --> Compare: 1559962503399_2200k.m3u8

  Error: Different target durations detected
  
  --> Detail:  Target duration: 5 vs Target duration: 4
  
  --> Source:  1559962503399_64k.m3u8
  
  --> Compare: 1559962503399_128k.m3u8

  UPDATE 1 :
  I modified the encoding command to utilize tee pseudo-muxer, but it seems the same issue still exists when segmenting HLS as byte-ranges rather than in separate .ts files :

  $ ffmpeg
  
  -hide_banner
  
  -report
  
  -benchmark
  
  -vstats
  
  -i "../Jane_shallowing_Top_v08.mp4"
  
  -dn
  
  -sn
  
  -filter_complex "[0:v]fps=fps=24.000,setpts=(PTS-STARTPTS),split=[vsplit1][vsplit2];[vsplit1]scale=-1:144[video_144];[vsplit2]scale=-1:1080[video_1080]"
  
  -map "[video_144]"
  
  -r:v:0 "24.000"
  
  -c:v:0 "libx264"
  
  -x264-params "keyint=144:min-keyint=144:scenecut=0:open_gop=0"
  
  -preset:v:0 "slow"
  
  -profile:v:0 "baseline"
  
  -refs:v:0 "2"
  
  -b-pyramid:v:0 "strict"
  
  -tune:v:0 "film"
  
  -b:v:0 "96000"
  
  -maxrate:v:0 "56000"
  
  -bufsize:v:0 "6*56000/8"
  
  -vsync:v:0 "cfr"
  
  -bsf:v:0 "h264_metadata=fixed_frame_rate_flag=1"
  
  -map "[video_1080]"
  
  -r:v:1 "24.000"
  
  -c:v:1 "libx264"
  
  -x264-params "keyint=144:min-keyint=144:scenecut=0:open_gop=0"
  
  -preset:v:1 "slow"
  
  -profile:v:1 "high"
  
  -refs:v:1 "2"
  
  -b-pyramid:v:1 "strict"
  
  -tune:v:1 "film"
  
  -b:v:1 "4800000"
  
  -maxrate:v:1 "4800000"
  
  -bufsize:v:1 "6*4800000/8"
  
  -vsync:v:1 "cfr"
  
  -bsf:v:1 "h264_metadata=fixed_frame_rate_flag=1"
  
  -map a:0 -map a:0
  
  -c:a "libfdk_aac"
  
  -ar "48000"
  
  -ab "128k"
  
  -af "aresample=async=1:min_hard_comp=0.100000:first_pts=0"
  
  -f "hls"
  
  -var_stream_map "v:1,a:0 v:0,a:1"
  
  -hls_time "6.000"
  
  -hls_segment_type "mpegts"
  
  -hls_flags "discont_start+temp_file+single_file"
  
  -hls_list_size "0"
  
  -master_pl_name "playlist.m3u8"
  
  -hls_segment_filename "out_%v.ts" "out_%v.m3u8" 

  Segment duration 98.0267, Playlist duration: 6.0000

• FFMPEG Interframe to intraframe without 'converting' or losing data

  11 août 2017, par Domenick Simpson

  I’m new to this so I apologise I couldn’t find the answer after searching.

  I am just ripping some video content for my film show-reel (specifically the Lego movie bluray) and came across some issues. When using ’makeMKV’ and ’xMedia Recode’ to perform a lossless transfer of the video data into an mp4 container I am getting artifacts in After Effects due to the interframe encoding of this bluray in H264 format. This doesn’t seem to be a problem with the Lego Batman movie bluray for some reason, maybe it uses Interframe. Anyway, some frames have block artifacts etc when editing / cutting shots.

  Is there a way to convert this original MP4 stream into the same format without losing data / into an intraframe mp4 for editing purposes ?

  I have used various re-encoding methods to H264 and prores that don’t result in block artifacts but result in less quality and different colourspace, and, higher file sizes.

  In FFMPEG I also tried exporting the mp4 as a png sequence but I assume due to the conversion of YUV to RGB I am getting quite noticeable differences in reds and gamma. I’d also prefer to keep this as a H264 or single video file if possible. Full disclosure, I tried various conversion types rgb24 etc to retain colour info but this didn’t work either.