Recherche avancée

Sur d’autres sites (13460)

• how to get 120fps encoded video to play at "normal" speed instead of slow mo

  1er mars 2023, par Patrick Vellia

  I used my GoPro Hero10 to record at 4k 120fps on a green screen. This original video plays slo-mo in QuickTime but "normal" speed in the browser. I want it playing normal speed, and if end user wants to slow it down they have the extra frames for that to maintain clarity, which is why I record at 120.

  


  I then used FFMPEG to create an image sequence of the video.

  


  Then I ran Image Magic to create the transparent frames.

  


  Then I put it back together with the following command for a HEVC mov file :

  


  ffmpeg -r 120 -f image2 -i transparent/image_transparent_%08d.png -vcodec hevc_videotoolbox -crf 28 -alpha_quality 1  -tag:v hvc1 output.mov


  


  I am still on an Intel MacBook Pro running FFMPEG 4.6 (as I've found 5+ was buggy with one of my commands a few months ago but can't remember which one, I think it was the videotoolbox).

  


  The GoPro video has the following stream data as input to the FFMPEG :

  


  Duration: 00:00:08.15, start: 0.000000, bitrate: 60160 kb/s
  Stream #0:0(eng): Video: hevc (Main) (hvc1 / 0x31637668), yuvj420p(pc, bt709), 3840x2160 [SAR 1:1 DAR 16:9], 59891 kb/s, 119.88 fps, 119.88 tbr, 120k tbn, 119.88 tbc (default)
    Metadata:
      creation_time   : 2023-02-28T19:06:41.000000Z
      handler_name    : GoPro H.265
      vendor_id       : [0][0][0][0]
      encoder         : GoPro H.265 encoder
      timecode        : 19:05:32:105
  Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 189 kb/s (default)
    Metadata:
      creation_time   : 2023-02-28T19:06:41.000000Z
      handler_name    : GoPro AAC  
      vendor_id       : [0][0][0][0]
      timecode        : 19:05:32:105
  Stream #0:2(eng): Data: none (tmcd / 0x64636D74), 0 kb/s (default)
    Metadata:
      creation_time   : 2023-02-28T19:06:41.000000Z
      handler_name    : GoPro TCD  
      timecode        : 19:05:32:105
  Stream #0:3(eng): Data: bin_data (gpmd / 0x646D7067), 76 kb/s (default)
    Metadata:
      creation_time   : 2023-02-28T19:06:41.000000Z
      handler_name    : GoPro MET  


  


  Whereas the re-constructed video has the following data :

  


  Duration: 00:00:08.13, start: 0.000000, bitrate: 763650 kb/s
  Stream #0:0: Video: hevc (Main) (hvc1 / 0x31637668), yuv420p(tv, progressive), 3840x2160 [SAR 1:1 DAR 16:9], 763696 kb/s, 120 fps, 120 tbr, 15360 tbn, 15360 tbc (default)
    Metadata:
      handler_name    : VideoHandler
      vendor_id       : FFMP
      encoder         : Lavc58.134.100 hevc_videotoolbo


  


  When this re-constructed video plays in the browser, it is in slow-mo and I need to set the playbackRate to 4.0 for it to play "normally".

  


  Is there something I need to add to the video for the browser to play it at "normal" speed ?

  


  EDIT

  


  I just compared the two video streams :

  


  original:
Stream #0:0(eng): Video: hevc (Main) (hvc1 / 0x31637668), yuvj420p(pc, bt709), 3840x2160 [SAR 1:1 DAR 16:9], 59891 kb/s, 119.88 fps, 119.88 tbr, 120k tbn, 119.88 tbc (default)

Reconstructed:
 Stream #0:0: Video: hevc (Main) (hvc1 / 0x31637668), yuv420p(tv, progressive), 3840x2160 [SAR 1:1 DAR 16:9], 763696 kb/s, 120 fps, 120 tbr, 15360 tbn, 15360 tbc (default)


  


  I don't quit understand all of this though. so here's what I notice :

  


  original.         reconstructed
--------------------------------
bt709             progressive
89871 kb/s.       763696 kb/s
119.88 fps.       120 fps
119.88 tbr.       120 tbr
120k tbr.         15360 tbr
11960 tbr.        15360 tbc


  


  Hmm. I suspect it has something to do with tbr and tbc whatever those are, or perhaps the progressive vs the bt709 ? the pirates are also vastly different.

  


• Revision 33150 : Essayer de suivre les optimisations de la 2.0.10++ SVN

  23 novembre 2009, par real3t@… — Log

  Essayer de suivre les optimisations de la 2.0.10++ SVN

• Convert GIF to MP4 with ffmpeg with palette color

  28 mars 2019, par NAG

  Palettegen is ok :

  ffmpeg()
  
  .input('temp/' + input.hash)
  
  .outputOptions(["-vf fps=15,scale=320:-1:flags=lanczos,palettegen"])
  
  .output('temp/palette.png')

  the conversion using the palette return a error :

  Error : Cannot find a matching stream for unlabeled input pad 1 on filter Parsed_paletteuse_0

  ffmpeg()
  
  .input('color=' + input.bg)
  
  .inputFormat('lavfi')
  
  .input('temp/' + input.hash)
  
  .inputFormat('gif')
  
  .input('temp/palette.png')
  
  .outputOptions('-lavfi paletteuse')
  
  .complexFilter(["[0][1]scale2ref[bg][gif]", "[bg]setsar=1[bg]", "[bg][gif]overlay=shortest=1[o]", "[o]scale=trunc(iw/2)*2:trunc(ih/2)*2"])
  
  .outputOptions(['-pix_fmt yuv420p', '-movflags frag_keyframe+empty_moov', '-movflags +faststart', '-crf 5'])
  
  .toFormat('mp4')
  
  .output('temp/final-' + input.hash)

  ffmpeg final command :

  ffmpeg -f lavfi -i color=ffffff -f gif -i temp/cf81f99083462f693406e8fd03ca7009 -i temp/palette.png -y -filter_complex [0][1]scale2ref[bg][gif];[bg]setsar=1[bg];[bg][gif]overlay=shortest=1[o];[o]scale=trunc(iw/2)*2:trunc(ih/2)*2 -lavfi paletteuse -pix_fmt yuv420p -movflags frag_keyframe+empty_moov -movflags +faststart -crf 5 -f mp4 temp/final-cf81f99083462f693406e8fd03ca7009