[bouqueau] fix SEI user data unregistered overflow
[bouqueau] fix SEI user data unregistered overflow
DmitrySigaev/gpac-sf,DmitrySigaev/gpac-sf,DmitrySigaev/gpac-sf,DmitrySigaev/gpac-sf,DmitrySigaev/gpac-sf,DmitrySigaev/gpac-sf