[LibVPX decoder] U/V swapped

[eumagga0x2a]

Avidemux decodes all WebM videos with U/V chroma components swapped. Inserting the "Swap UV" filter restores the correct colors.

A possible testcase: https://www.youtube.com/watch?v=2-QbUQUaB24, use the video with the format code 43.

Avidemux built from https://github.com/mean00/avidemux2/commit/3ce52bbdcd2bd52f217c32d8c5780c350d0764fd.

PS: if the issue affects other Linux distributions (Ubuntu etc.) and even other platforms, this could be IMVHO a release blocker.

[mean]

It's not a general problem, other VP9 videos are fine

[eumagga0x2a]

You're right, now I see that only VP8 is affected.

[eumagga0x2a]

Oh my..., did the issue exist all the time at least since the code in avidemux_plugins/ADM_videoDecoder/vpx/ was last touched in e7a1b99311f0548eec40cac1863f4dbe17edb54a 4 years ago, but probably much longer?