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• FireFox Video throws warning but video actually works ?

  21 février 2021, par SdBill
  

  • OS : Ubuntu 18.04

  


  • FF : 85.0.1

  


  • Error/warning : Cannot play media. No decoders for requested formats : video/mp4, video/mp4

  


  


  Same error for video/ogg

  


  Here are my questions : 1) The video still plays fine once loaded, and there is no error in Chrome or Chromium. Why does the video work fine after loading but throws the error on load ? 2) Is there anything that can be done without re-encoding over 2 gigs of video ?

  


  Context : this is an old no-profit site that used Flash for video and we really don't want to throw a lot of time at, but there are gigs of videos. I converted all .flv files and .mpg files to .mp4 using the most simple of ffmpeg commands, examples :

  


  ffmpeg -i video-source.flv video-source.mp4
ffmpeg -i video-source.mpg video-source.mp4
ffmpeg -i video-source.mpg video-source.ogg


  


  As I watched the ffmpeg output, it looked to me like the codec was H264 (at least, I think that is what I am seeing, not a video expert.)

  


  Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> theora (libtheora))
  Stream #0:1 -> #0:1 (aac (native) -> vorbis (libvorbis))


  


  Server response in a direct request to the mp4 files is

  


  Content-Type
    video/mp4


  


  I have seen the documentation and posts on fragmented mp4 and if re-encoding is the only option, we're probably going to abandon as it does play once loaded.

  


  Code is simplistic, using an html5 doctype :

  


    <video width="320" height="240" controls="controls">&#xA;   <source src="/images/video/mp4/video-source.mp4" type="video/mp4">&#xA;   <source src="/images/video/ogg/video-source.ogg" type="video/ogg">&#xA;   Your browser does not support the video tag.&#xA;  </source></source></video>&#xA;

  


  Is the only option here to pander to FireFox and re-encode everything since as mentioned, it plays fine once loaded and throws no error in Chrome ?

  


• FFMPEG Partial Audio Filter of Video File

  12 avril 2024, par Cole

  I am trying to apply an audio filter to a section of the audio track on a video file.

  


  Here are some details.
"video.mp4" is 1 minute and 36 seconds long. I want to lower the pitch of the first 30 seconds of the file. The video track does not need any change, so I can copy that and only transcode the audio. Note, I will have to do this same operation to other videos, with the pitch change at different times. This one is at the beginning, however.

  


  I have used this post for inspiration : https://superuser.com/questions/977743/ffmpeg-possible-to-apply-filter-to-only-part-of-a-video-file-while-transcoding

  


  I have tried the following :

  


  ffmpeg -i video.mp4 -filter_complex "[0:a]trim=start=0:duration=30,rubberband=pitch=0.5[a2];[0:a]trim=start=30[a3]" [a2][a3]concat[a] -map [a] -map [0:v] -c:v copy output.mp4


  


  The above combines the trim and rubberband into one action, but maybe that does not work (same error). In the below I separate them out.

  


  ffmpeg -i video.mp4 -filter_complex "[0:a]trim=start=0:duration=30[a1];[a1]rubberband=pitch=0.5[a2];[0:a]trim=start=30[a3]" [a2][a3]concat[a] -map [a] -map [0:v] -c:v copy output.mp4


  


  My thought process with the above is to take the audio track [0:a] and trim it to the portion I want to edit, now a1. Then apply the filter and make that a2. Lastly, take the other portion of the audio and save it as a3 (is this step even necessary ?). I concatenate the modified audio and unmodified audio (a2 and a3, respectively), then map the audio and video channels and output the final product.

  


  The error I receive is below.

  


  [Parsed_trim_0 @ 0x5623a0b03040] Media type mismatch between the 'Parsed_trim_0' filter output pad 0 (video) and the 'Parsed_rubberband_1' filter input pad 0 (audio)
[AVFilterGraph @ 0x5623a0ab6100] Cannot create the link trim:0 -> rubberband:0
Error initializing complex filters.
Invalid argument


  


  I think that this error is related to an audio/video track issue, but I don't know where to begin. Where am I going wrong ? What other suggestions do you have that I have not considered ?

  


  Edit : Thank you for pointing out the atrim ! That solved that particular issue. There were some other issues I had to figure out as well.

  


• avr32 : remove explicit support

  9 juin 2024, par Rémi Denis-Courmont

  avr32 : remove explicit support
  The vendor has long since switched to Arm, with the last product
  
  reaching their official end-of-life over 11 years ago. Linux support for
  
  the ISA was dropped 7 years ago. More importantly, this architecture was
  
  never supported by upstream GCC, and the vendor fork is stuck at version
  
  4.2, which FFmpeg no longer supports (as per C11 requirement).
  Presumably, this is still the case given the lack of vendor support.
  
  Indeed all of the code being removed here consisted of inline assembler
  
  scalar optimisations. A sane C compiler should be able to perform those
  
  automatically nowadays (with the sole exception of fast CLZ detection),
  
  but this is moot as this architecture is evidently dead.
  

  • [DH] configure
  • [DH] libavcodec/avr32/mathops.h
  • [DH] libavcodec/mathops.h
  • [DH] libavutil/avr32/intreadwrite.h
  • [DH] libavutil/intreadwrite.h