Adopting AV1 for Real-Time Communication (RTC) at Scale

This post details Meta's multi-year effort to adopt the AV1 video codec for real-time communication (RTC) across Messenger and WhatsApp. It outlines the technical and operational challenges encountered, including codec selection, device eligibility, rate control, and error resilience. Key contributions include the development of a low-complexity AV1 encoder with an ultra-low-complexity preset comparable to H.264/AVC, the selection of the dav1d decoder for its power efficiency, strategies for reducing binary size impact, and the creation of an ML-based device eligibility framework to reliably categorize device capabilities for AV1 support. The post also highlights AV1's advantages for screen content encoding using palette mode and intra-block copy.