As AV1 is still slowly taking off, experimental support for next gen AV2 lands

AV2 unofficial logo

The Alliance for Open Media was formed back in 2015 and in 2018, the consortium released its AV1 video codec. The royalty-video format was made such that it could compete with H.265 (HEVC). So far, the AV1 codec has seen some slow but steady adoption with YouTube kicking it off in 2018 itself, with Netflix following in 2020. More recently in 2022, Apple seems to be expanding support for AV1 too.

Seeing how the adoption of such technologies can take so much time, the Alliance for Open Media (AOMedia) has already begun to add support for the succeeding AV2 codec. The support is still experimental though and quite preliminary. It looks to be in relation to the AVIF (AV1 Image File Format) for now. The pull request says (via Phoronix):

Add AV2 support

Experimental. The AV2 specification is not finalized.

Handle av02 image item type and av2C configuration property.
Handle av02 track sample format.
Add avifavmtest.
Disable AV1 tests when all AV1 codecs are disabled.
Add presubmit ci-unix-static-av2.yml.

libavif can only generate AV2 files if it is built with AVIF_CODEC_AVM set to ON. The avifEncoder API can only output AV2 files if codecChoice is explicitly set to AVIF_CODEC_CHOICE_AVM to avoid mistakes. avifenc can only output AV2 files if --codec=avm is specified to avoid mistakes. aom and avm conflict and cannot be used together in the same libavif binary. Other AV1 codecs can be enabled alongside aom. libavif will decode any AV1 or AV2 file by default as long as the relevant codecs are enabled. The main behavior change for libavif with only AV1 codecs enabled is that before this change, items or tracks of type 'av02' were ignored. After this change, conformant AV1-AVIF files with extra 'av02' items will fail to decode unless avm is enabled. This change allows decoding files with mixed AV1 and AV2 items or tracks (untested because no encoding tool for that). This decision can be changed in the future.

In related news, Microsoft's Edge is also getting support for the image format. Competing browsers like Chrome and Firefox have had AVIF support for a while.