libaom is the reference AV1 encoder and decoder from the Alliance for Open Media (AOMedia). As the official reference implementation, it sets the standard for what AV1 can do — every feature in the AV1 specification is implemented and verified in libaom first. The trade-off: libaom prioritises completeness and quality over speed, so it's typically the slowest AV1 encoder. Encoding a 4K movie at its highest quality preset can take days on a powerful server.
The slowness is not a bug; it's the design. libaom does exhaustive mode-decision evaluation that finds compressions a faster encoder would miss, producing files 5–15 % smaller at the same VMAF than the otherwise-better-known SVT-AV1. For content where every byte matters — Netflix's "golden master" encodes for premium catalogue, archival-quality compression, codec efficiency benchmarks — libaom is the standard reference. For everyday production work where the same quality at 10× the speed matters more, SVT-AV1 is the practical choice.
For a product team, libaom is mostly the benchmark you measure other AV1 encoders against, not the one you ship. If a vendor claims their AV1 encoder produces files 5 % smaller at the same VMAF, "smaller than what?" — likely smaller than libaom on a fast preset, which is a real but modest claim. If they claim smaller than libaom at its slowest preset, that's a much stronger claim. For practical encoding work in 2026, SVT-AV1 at presets 4–6 gives 95 % of libaom's quality at 10–20× the speed, which is the right choice for everything except certain premium catalogue encodes. libaom's decoder side (libaom-dec, dav1d from VideoLAN is the faster decoder alternative) is widely used as fallback software AV1 decoding on platforms without hardware AV1 decode.
