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VP9 is Scrambled

Started by AQUAR, January 29, 2016, 06:18:52 AM

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AQUAR

I wanted to try out the new slider behaviour with UHD-VP9-Webm videos.

Unfortunately - ADM plays the HD and UHD VP9 videos in quite a messed up manner (scrambled except for index frames!).
I got the same result using the latest version of VLC (both use FFMPEG for decoding UHD VP9).

However, VLC with hardware accelerated decoding turned off, does play the VP9 videos.
(HD only on my older ATI HD3600 and UHD on the newer ATI HD5670)

It appears therefore to be an issue with FFMPEG using DXVA1/2 (as well as GPU capability).

Is there a way I can stop ADM from using DXVA?


mean

Avidemux (sadly) does not use DXVA on windows

AQUAR

If not DXVA then I can only assume it may be an issue with ffvp9/libvpx-vp9 in ADM's version of FFMPEG.
Is it current?

mean


AQUAR

Would be interesting if some other windows users could try playback of VP9 on ADM.

A sample HD video can be had at https://people.gnome.org/~rbultje/vp9/etv5k-vp9-b5000.webm

If it plays back fine - what hardware is being used (CPU & GPU).

Jan Gruuthuse

Is not playing correctly either in ADM on ubuntu :(

AQUAR

Have a look at this site:
https://blogs.gnome.org/rbultje/2014/02/22/the-worlds-fastest-vp9-decoder-ffvp9/

Scroll down to the decoder section and you will find a number of smallish sample VP9 videos used to test decoder speeds.
They are at various bit rates - see if the ones at lower bit rates work on your PC.

VLC playback behaviour for VP9 with higher bit rates is different on my hardware platforms (all with hardware acceleration turned off!).

VP9 is still pretty new and we can expect open source codecs for it to improve over time.

I tested the slider behaviour on these VP9 videos and it works fine at 20 ms (display refreshes on intra frames - the only frames which are decoded correctly!).

 

Jan Gruuthuse

#8
none of my vp9 / webm do play, have to look in to this and report later.

seems something did break?

AQUAR

I installed the directshow filter for VP9 from the webm project site.
All these VP9 sample videos do play fine in windows media player, even on my aging core2duo with an ancient graphics card.

Will give it a rest for now as I think its probably some lavcodec related issue that will eventually be sorted out.




Jan Gruuthuse

only plays in firefox browser

AQUAR

Various browsers now use the VP9 codec from google or the webm project.
Its interesting to know that our "decoding" issue lies not with the VP9 in webm videos.

Since webm is just a subset of MKV I tried these VP9's in MKV, but as expected it made no difference (I thought maybe a de-muxing issue with audio).

I will try avplay with the latest nightly for libav and see if these videos play on my PC.
It's more curiosity than need as before the slider behaviour change I never even had a VP9 encoded video in the webm container.