Eugene Zemtsov

[VideoFrame.allocationSize()](https://www.w3.org/TR/webcodecs/#dom-videoframe-allocationsize) is synchronous and it throws if conversion is not supported.

Yes, we should consider introducing `VideoFrame.canCopyTo()`, especially if we end up adding more format options to [VideoFrameCopyToOptions](https://www.w3.org/TR/webcodecs/#dictdef-videoframecopytooptions)

To me it looks like [Relaxed_Memmove](https://source.chromium.org/chromium/chromium/src/+/main:v8/src/base/atomicops.h;l=388;drc=728231103e6768cd9387b68b25b52e970f499065) itself contains an UB from C++ point of view. Does the C++ standard guaranty that atomic and T are the same thing and can...

Correct. 0-63 is the user input range, specified by the application. That is the same range for VP8/VP9/AV1. But the internal QP range (QP actually used by the encoder) is...