[AVTCORE] Implementation Query: Picture Abstraction in RFC 9628
Diptanu De <shaandip99@gmail.com> Sat, 02 May 2026 13:11 UTC
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Subject: [AVTCORE] Implementation Query: Picture Abstraction in RFC 9628
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Date: Sat, 02 May 2026 13:11:46 -0000
X-Original-Date: Sat, 2 May 2026 18:41:17 +0530
Dear Author(s), I’ve been studying *RFC 9628* and and would like to commend the design, particularly the introduction of the *“picture” abstraction*. I have a specific question regarding the implementation of such an* abstraction*. While a "picture" functionally mirrors a VP9 *superframe*, the RFC distinguishes between the two. In the VP9 bitstream, superframe detection is explicit and deterministic via the superframe index. However, the mechanism for detecting a "picture" from the bitstream seems less defined. Could you please clarify the intended implementation for picture detection? Specifically: - Is it intended to be derived solely from *RTP-level signaling* (Picture ID/Layer Indices) within the depacketizer? - Or is there a deterministic way to identify these boundaries within the bitstream itself without modifying underlying codec behavior? I find this design choice very interesting and would appreciate your perspective on how authors envision a robust decoder implementation. Thank you for your time and for your significant contributions to this specification. Best regards, Diptanu D.