VP09 codec question

[ruurik]

Hi 

First time poster.

Does avidemux support editing videos encoded with the vp09 codec?

Thanks for any replies.

[eumagga0x2a]

Yes, VP9 should not pose a problem* (of course, as always, the latest nightly or at least the last release is presumed).

*) in containers which support VP9 which are Matroska (mkv) and WebM (webm) only.

[ruurik]

Thanks for your reply eumagga0x2a. I've started getting a problem editing longer videos from YouTube in the past week or so. I'm on the latest nightly release of Avidemux.

When I edit the video, it looks like this. Notice the bottom strip of noise. The colours in this strip move a little as the video plays. The sound plays fine.



The video plays ok in VLC and Windows Media Player.

This is the information from mediainfo:



Any ideas what is happening? Thanks for any replies.

[eumagga0x2a]

Don't force youtube-dl to merge VP9 and Opus in MP4, this is unsupported. Use Matroska/WebM (which is also youtube-dl default).

[ruurik]

That's great, thanks a lot eumagga0x2a. Previously I'd been using "9convert . com / en10" and "loader . to / en7 / ?" rather than youtube-dl to download videos. After trying youtube-dl, I can edit them again. THANK YOU! 

[eumagga0x2a]

I'm about to add support for VP9 to MP4 demuxer in Avidemux.

However, you should not use MP4 generated by FFmpeg from WebM as source for cut operations in Avidemux when fps means that frame duration is not a multiple of 1 ms. The reason is that FFmpeg turns such videos into videos with variable frame rate (it keeps timing from the source Matroska container). Avidemux takes this in MP4 files literally while in MKV/WebM it tries to reinterpret such videos correctly as constant frame rate of 30000/1001 or 24000/1001.

[ruurik]

Thanks for the info eumagga0x2a.

[eumagga0x2a]

Done.