On Fri, Jan 26, 2024 at 1:23 PM Kimmo Virtanen <kimmo.virtanen@wikimedia.fi> wrote:
Could somebody explain what is problem with VP9 or AV1 with WebM container? These are supported in Wikimedia Commons.

OK, I will try to answer my own question:

AV1 is technically superior to h.264 in terms of file size and quality as it is one generation newer.  h.265 (HVEC) would be in quality level than AV1, but there is licence fee for using it and open source tools support is better for AV1 than h.265. If we include closed source encoders then h.265 encoders are in ame level than open source AV1 encoders. AV1 is generally widely used as it is used by Netflix and Youtube etc.

Browser support for AV1 seems to be OK
https://caniuse.com/?search=VP9

The missing thing is that hardware support is in the transition phase. Ie. Most notably, widely available Apple support is missing as it supports AV1 only devices where there is hardware support for decoding. Apple added hardware decoding AV1 support to its latest generation chipsets (A17, M3). 

On Android Google defined that AV1 support is mandatory for Android 14 (released 2023) compliance. 

On PC side hardware decoding / encoding support has been added like this
* AMD RDNA2 = AV1 decode (released 2020)
* AMD RDNA3 = AV1 decode/encode (released 2022)
* Intel 11th gen = AV1 decode (released 2021) 
* Intel 14th gen = AV1 decode/encode (released 2023)

So, all new devices which are released in 2024 will support AV1 and in a couple years perspective the devices which don't support AV1 are legacy ones. Hardware decoding is relevant for mobile devices as without it power consumption would be too high even if the device could decode the stream. Legacy desktop computers can do the software decoding in terms of CPU/GPU performance required.

Br,
-- Kimmo Virtanen, Zache