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• writing custom codecs for android using FFmpeg

  22 mai 2014, par Aditya Kumar Praharaj

  I am doing a video compression project for Android and I am thinking of implementing it by designing a new video codec (by scratch , I have designed the algorithm) . I have already read the basics of video compression , related relevant algorithms and codec basics . I have also found that FFmpeg may serve as a quite good solution on Android.

  Now my questions come :

  1. How to write a new video codec as in FFmpeg ? I am still a beginner at writing codecs , but
     how do I start ? I have a rough idea that that you have to write at least a demuxer first and then the specific encoder and decoder etc . (Asking for references here please.)

  2. Since my codec deosn’t simply adjust video properties like fps , resolution , bit-rate etc.
     Is reading the MediaCodec API and MediaPlayer API in official Android SDK enough for writing new codecs ? (Because last time I saw it had only support for MPEG-4 SP , H.263 and H.264 . I was unable to find if you could directly write your own classes and functions).

  Thanks .

• Transcoding ERROR : jellyfin-ffmpeg/lib/dri/iHD_drv_video.so init failed

  24 mars 2023, par Souleimen BENTRAIFA

  Here is my problem, I switched from Jellyfin Win10 to Jellyfin via OMV6 Portainers (official images).
I have I7-2600S (VAAPI)

  


  Except that the transcoding doesn't work anymore, in the Jellyfin logs I have the following error message :

  


  [h264_vaapi @ 0x557ec1743400] No usable encoding entrypoint found for profile VAProfileH264High (7).
Error initializing output stream 0:0 -- Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height


  


  In the attachment you will find information after the "vainfo" we have the following error

  


  screenshot vainfo command here

  


  libva error: /usr/lib/jellyfin-ffmpeg/lib/dri/iHD_drv_video.so init failed


  


  If anyone has a clue, let me know

  


  NOTE : In Windows 10 i have no problem to transcoding in any format

  


• FFMPEG via PHP - no thumbnail or log output generated

  10 octobre 2018, par Utkanos

  I’m trying to get my head around command line syntax in the form of FFMPEG via PHP.

  I’ve successfully installed it and I can use it fine, until I try to :

  • run background tasks
  • generate output to a log

  This code attempts to create a thumbnail from a video. And it does, if I make it synchrnous, i.e. remove everything from onwards code>....

  shell_exec($i = 'ffmpeg -y -i '.$fp.' -ss '.$secs.' -vframes 1 '.$dirs_path.'/thumb.png  null >/dev/null 2>/ffmpeg.txt &');

  I’ve derived the background part of this command from this page on the official FFMPEG site.

  ($secs is an integer denoting a seconds point within the video duration, and $fp is the save path of the video. Both are valid.)

  So the thumb doesn’t get generated, and there’s no ffmpeg.txt created, either in the place where the script runs, or in the server root or anything. I may be looking in the wrong place... I’m unsure what all this is relative to.

  Any help appreciated.