Uninitialized predFlagLXConstK in Section 8.5.5.6

[bheng]

In Section 8.5.5.6, predFlagLXConstK are never set to 0. They are either set to 1 or undefined.

Ideally, it would be a good idea to specify predFlagLXConstK = 0, refIdxLXConstK = -1, and cpMvLXConstK = (0,0) for all the availableFlagLX equal to FALSE conditions so that there aren't undefined reference index and motion vectors floating around. Otherwise conditions elsewhere such as "... have the same motion vectors and the same reference indices" aren't strictly defined.

[jlchen]

Thanks for reporting the issue. The following initialization will be added to section 8.5.5.6.

The availability flags of the constructed affine control point motion vector merging candidates availableFlagConstK, with K = 1..6, are initialized to be equal to FALSE.

For the suggestion of setting "refIdxLXConstK = -1, and cpMvLXConstK = (0,0) for all the availableFlagLX equal to FALSE", I tend to NOT doing it since many places need to be considered and it's easy to overlooked.

[bheng]

The text to initialize availableFlagConstK was the fix for Ticket #1293. But, I don't think it solves the problem for initializing predFlagL0ConstK = 0 and predFlagL1ConstK = 0, in case an available candidate doesn't use List0 or List1 prediction.

[jlchen]

Yes, you're right. Would the following initialization process of the predFlagLXConstK solve the problem?

The prediction list utilization flags predFlagLXConstK, with with K = 1..6, X = 0..1, are initialized to be equal to FALSE.

[bheng]

Yes, that would work fine. Thanks!

[jlchen]

Thanks for comfirmation.