WebM videos are crippled and unusable. Is support broken?

Development Cinematics & Media
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1

Hi all. Has anyone had luck playing a WebM file in the Media Framework? Every file we tried is crippled somehow. There’s been official support for a while and it’s the ideal video format since it’s lightweight and works across Windows, Mac and Linux, but playing in-game videos seems to be currently broken:

  1. Frames are skipped for no reason
  2. Videos will slow down erratically
  3. They are always cropped near the right border…
  4. As a result, all videos look stretched horizontally!

Take a look at this original video: Dropbox - File Deleted

Now see how it looks through render to texture in our game: Dropbox - File Deleted

The behavior is the same if using a Media Player asset and this still happens in 4.23, be it Win/Mac/Linux. We’re converting all our videos with ffmpeg and tried both VP8 and VP9 codecs.

I’m surprised there’s no mention of this issue with WebM anywhere — I wonder if we’re the only ones needing to use it because the format is decidedly unusable at this point. Yet in theory it’s officially supported. Note that MP4 and sequences of images work well in our code.

I’ll be posting a formal bug report as well, but I wanted to check in here if anyone else is experiencing this issue. Maybe it’s a particular setting in ffmpeg that has to be used and we’re missing something. Thanks much in advance!

2

Thanks, I submitted the formal report as well.

3

Hello,

We’ve recently made a switch to a new bug reporting method using a more structured form. Please visit the link below for more details and report the issue using the new Bug Submission Form. Feel free to continue to use this thread for community discussion around the issue.

https://epicsupport.force.com/unrealengine/s/

Thanks

4

Hello @Senscape , sorry for reviving old wounds, did you eventually figure out a setting that works? Webm videos are very choppy on Linux at the moment, and they’re our only option for media playback on Linux it seems. Thanks!

5

Hello, @Senscape @elbriga14. I am having trouble using the WebMMedia plugin for media playback. I used ffmpeg to convert the .mp4 file to a .webm file.

Commands used:

ffmpeg -i ./myvideo.mkv -c:v vp8 -pass 1 -b:v 4000k -crf 10 -c:a libvorbis -af loudnorm=I=-16:LRA=11:tp=-1.0:print_format=json -f webm NUL
ffmpeg -i ./myvideo.mkv -c:v vp8 -pass 2 -b:v 4000k -crf 10 -c:a libvorbis -af loudnorm=I=-16:LRA=11:tp=-1.0:measured_I=-19.22:measured_LRA=4.80:measured_tp=-3.11:measured_thresh=-29.45:offset=-1.04 -ar 48k -f webm ./myvideo.webm

When I try to play the video, my game crashes with the following error.
Assertion failed: vpx_codec_dec_init_ver(&Context, vpx_codec_vp9_dx(), &CodecConfig, 0, (3 + (3 + (4)))) == 0 [File:D:/Build/++UE4/Sync/Engine/Plugins/Media/WebMMedia/Source/WebMMedia/Private/Player/WebMVideoDecoder.cpp] [Line: 89]

Can you help me troubleshoot this issue.

Thanks.

Additional info: ffmpeg version 3.4.11-0ubuntu0.1