[FFmpeg-devel] [PATCH v3] avformat: add AV1 RTP depacketizer and packetizer

[Tristan Matthews]

Hi,

> I see. I've put the code in an #if <somedefine> block, so you can try if
>
> it makes a difference to anything you may encounter.
>
> The spec says: https://aomediacodec.github.io/av1-spec/#ordering-of-obus
>
> "Sequence header OBUs may appear in any order within a coded video
> sequence. Within a particular coded video sequence, the contents of
> sequence_header_obu must be bit-identical each time the sequence header
> appears except for the contents of operating_parameters_info. A new
> coded video sequence is required if the sequence header parameters change."
>
> So if an encoder decides to submit Sequence Header OBUs in any
> non-keyframe to maybe change the operating_parameters_info, this will
> break both GStreamer and WebRTC?
>

No I don't think so, since they only set the N bit of the aggregation header if a) this is a keyframe and b) a sequence header is present. A keyframe with no sequence header (which an encoder might decide to emit) or a sequence header in a non-keyframe like you're describing will not result in the N bit being set.

Hopefully that clarifies things.

Best,
Tristan