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• Playing video with transparency in iOS

  14 juillet 2020, par 0Ds0

  A bit of background, i want to play videos with transparency on the web converted from gifs, for all non apple devices i can easily export a webm file like so

  


  ffmpeg -i test.gif -c:v libvpx-vp9 -qmin 0 -qmax 18 -crf 9 -b:v 1400K -quality good -cpu-used 0 -auto-alt-ref 0 -pix_fmt yuva420p -an -sn  -metadata title="test webm" test.webm

  


  No need for video streaming with HTTP response 206 partial content loaded it works out of the box

  


  Now for safari and apple devices i am presented with a totally different beast i set up a endpoint that serves the video with HTTP 206 responses and after a quite a struggle i can have the same end result for Safari in macOSX, and i convert the videos like so

  


  ffmpeg -i test.gif -qmin 0 -qmax 18  -vcodec prores_ks -q:v 64 -b:v 1400K  -pix_fmt yuva444p10le -profile:v 4444 -an -sn -metadata title="test mov" test.mov

  


  I put in the url address bar the that serves the video with stream and the video plays with transparency all good.

  


  Now on Safari in iOS the video just does not play, it is loaded with the same endpoint and other videos without transparency also work, serving from the same stream endpoint.

  


  Does anyone knows of a solution to encode a video with transparency that plays on all apple devices ?

  


  I also gave handbrake a try without success, actually could not even get the transparency right with handbrake.

  


• ffmpeg - DF vs NDF (Drop Frames) vs (Non Drop Frames), how to simply pass input timecode to output

  24 septembre 2020, par Selene

  Please help with this issue. The broadcaster just rejected my submitted video because their validation tool threw this kind of error :

  


  


  was configured as "Non drop Frame". "Drop Frame" expected.

  


  


  I'm only processing video, and I expect the audio to just be copied from input to output.
Running and comparing input with output using ffprobe shows difference in timecode :

  


    Metadata:
    major_brand     : qt  
    minor_version   : 537199360
    compatible_brands: qt  
    creation_time   : 2020-02-29T22:07:42.000000Z
  Duration: 00:00:20.05, start: 0.000000, bitrate: 133935 kb/s
    Stream #0:0(eng): Video: dvvideo (dvh6 / 0x36687664), yuv422p(bt709, top coded first (swapped)), 1280x1080 [SAR 3:2 DAR 16:9], 115084 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 29.97 tbc (default)
    Metadata:
      creation_time   : 2020-02-29T22:07:42.000000Z
      handler_name    : Apple Video Media Handler
      encoder         : DVCPRO HD 1080i60
      timecode        : 00:00:00;00
    Stream #0:1(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, mono, s32 (24 bit), 1152 kb/s (default)
    Metadata:
      creation_time   : 2020-02-29T22:07:42.000000Z
      handler_name    : Apple Sound Media Handler
      timecode        : 00:00:00;00
    Stream #0:2(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, mono, s32 (24 bit), 1152 kb/s (default)
    Metadata:
      creation_time   : 2020-02-29T22:07:42.000000Z
      handler_name    : Apple Sound Media Handler
      timecode        : 00:00:00;00
    Stream #0:3(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, mono, s32 (24 bit), 1152 kb/s (default)
    Metadata:
      creation_time   : 2020-02-29T22:07:42.000000Z
      handler_name    : Apple Sound Media Handler
      timecode        : 00:00:00;00


  


  After video conversion, the output of ffprobe :

  


    Metadata:
    major_brand     : qt  
    minor_version   : 512
    compatible_brands: qt  
    encoder         : Lavf58.58.100
  Duration: 00:00:20.05, start: 0.000000, bitrate: 167037 kb/s
    Stream #0:0(eng): Video: prores (XQ) (ap4x / 0x78347061), yuv422p12le(tv, bt709, top coded first (swapped)), 1920x1080, 148578 kb/s, SAR 1:1 DAR 16:9, 29.97 fps, 29.97 tbr, 30k tbn, 30k tbc (default)
    Metadata:
      handler_name    : Apple Video Media Handler
      encoder         : Lavc58.106.100 prores_ks
      timecode        : 00:00:00:00
    Stream #0:1(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, 1 channels, s32 (24 bit), 1152 kb/s (default)
    Metadata:
      handler_name    : Apple Sound Media Handler
    Stream #0:2(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, 1 channels, s32 (24 bit), 1152 kb/s (default)
    Metadata:
      handler_name    : Apple Sound Media Handler
    Stream #0:3(eng): Audio: pcm_s24le (in24 / 0x34326E69), 48000 Hz, 1 channels, s32 (24 bit), 1152 kb/s (default)
    Metadata:
      handler_name    : Apple Sound Media Handler


  


  My encoding string looks like this :

  


  ffmpeg -i input.mov -vf scale=1920x1080 -map 0:v? -map 0:a? -map 0:s? -map 0:d? -b:v 115084915 -maxrate 115084915 -minrate 115084915 -c:v prores_ks -profile:v 5 -preset ultrafast -crf 0 -c:a copy -c:s copy -y output.mov


  


  Please help !

  


• How to create Automator service for multiple ffmpeg command

  31 janvier 2017, par user413734

  There are many tutorials for creating an automator service that calls an ffmpeg one liner script, like so e.g :

  http://apple.stackexchange.com/questions/129929/automating-ffmpeg-using-automator-service

  But I would like this service to do more than just a one liner. There is the option to chain commands with && but that makes it rather confusing.
  How can I create an automator service that does one transformation and after it is done the next line etc, e.g :

  for f in "$@"
  
  do
  
      ffmpeg -i "$f" -c:v copy -c:a copy "${f%.*}.mp4"
  
      ffmpeg -ss 00:00:01 -i "$f" -frames:v 1 "${f%.*}.jpg"
  
      ....
  
  done

  Or attach this service to one folder that if I drop a file it automatically does the require conversions.

  Thanks