Yueshi Shen

Principal Research Engineer, Twitch


Dr. Yueshi Shen oversees Twitch’s transcoder team, driving the R&D of Twitch's core video technologies. Dr. Shen initiated and built a number of Twitch’s core video capabilities, e.g., cost-effectively live-video transcoding farm supporting over 50,000 concurrent channels, live ABR playback algorithm designed for highly interactive content, HLS-based low-latency (<5s) live HTTP streaming. Prior to Twitch, Dr. Shen led the development of GD Mediaware’s award-winning H.264/TS ad splicing system and Ambarella’s H.264/SVC codec firmware. He also developed OnLive’s ultra-low-latency video streaming technology for their cloud gaming service. Dr. Shen is the inventor of AV1’s SWITCH_FRAME and has filed 15 patents.

Conference Talk

Towards a healthy AV1 ecosystem for UGC platforms

Twitch is a UGC live streaming platform with more than 100k concurrent channels at its peak. Currently, to avoid excessive replication cost, Twitch only supports 1 codec format (i.e., H.264) for most of those live channels. On the other hand, as we also want to achieve savings on the last-mile traffic cost, Twitch recently started streaming VP9 and H.264 for a small number of high-viewership channels.

Having multiple codec formats in the video pipeline incurs operation risks and extra cost, and to move the entire platform from H.264 to AV1 brings significant commercial benefits including cost savings, better QoS, as well as low latency. This talk will explain Twitch’s strategy of pushing UGC platforms for adopting AV1, and review the multiple factors that affect each other but together can create a healthy AV1 ecosystem.