fix: improve initial video quality by setting x-google-start-bitrate for all video codecs#1120
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…for all video codecs - Apply x-google-start-bitrate SDP hint to all video codecs (VP8, VP9, AV1, H264, H265), not just SVC codecs - Use 90% of target bitrate as start bitrate to prevent initial blurriness - Degradation preference already defaults to maintainResolution This addresses the issue where video starts blurry for several seconds before improving, by telling WebRTC's bandwidth estimator to start at a higher bitrate instead of ramping up from ~300kbps. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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Summary
x-google-start-bitrateSDP hint to all video codecs (VP8, VP9, AV1, H264, H265), not just SVC codecsmaintainResolutionProblem
Video starts blurry for 5-15 seconds before improving. This is caused by WebRTC's bandwidth estimator starting at ~300kbps and slowly ramping up to the target bitrate.
Solution
x-google-start-bitrate: Tell WebRTC to start at 90% of target bitrate instead of ramping up from ~300kbps. Applied consistently to all video codecs.
Note, The PR only addresses the x-google-start-bitrate fix (changing from SVC-only to all video codecs, and using 0.9 multiplier)
Test plan
🤖 Generated with Claude Code