follow-up on #2462 (deleted) and fe02e73f (reverted) 

In GPAC, we treat all NAL types indicating IDR/BLA with decodable leading pictures as SAP2 if and only if the following picture has a poc less than the sap picture, otherwise we use SAP1.

We do this because many encoders use decodable leading pictures NAL type signaling when they in fact use simply IDRs. Not doing so would end up having SAP2 indicated in e.g. DASH manifest, which may break validation by some players.

Note that we don't change the NAL type, just the SAP type.


Note on SAP2 handling
This is a GitHub Issue
repo:gpac
owner:gpac
Title : Note on SAP2 handling
Issue date:

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follow-up on #2462 (deleted) and fe02e73f (reverted) 

In GPAC, we treat all NAL types indicating IDR/BLA with decodable leading pictures as SAP2 if and only if the following picture has a poc less than the sap picture, otherwise we use SAP1.

We do this because many encoders use decodable leading pictures NAL type signaling when they in fact use simply IDRs. Not doing so would end up having SAP2 indicated in e.g. DASH manifest, which may break validation by some players.

Note that we don't change the NAL type, just the SAP type.


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