Inference rule for pt_present_flag[0]

[vdrugeon]

The inference rule for pt_present_flag[0] seems strange.

pt_present_flag[ i ] equal to 1 specifies that profile, tier, and general constraints information are present in the i-th profile_tier_level( ) syntax structure in the VPS. pt_present_flag[ i ] equal to 0 specifies that profile, tier, and general constraints information are not present in the i-th profile_tier_level( ) syntax structure in the VPS. The value of pt_present_flag[ 0 ] is inferred to be equal to 0. When pt_present_flag[ i ] is equal to 0, the profile, tier, and general constraints information for the i-th profile_tier_level( ) syntax structure in the VPS are inferred to be the same as that for the ( i − 1 )-th profile_tier_level( ) syntax structure in the VPS.

If pt_present_flag[0] is equal to 0, then the profile, tier and general constraints information for the first PTL structure is never signalled. As a consequence, if pt_present_flag[1] is equal to 0, the profile, tier and general constraint information cannot be inferred, because it is not available for the 0-th PTL structure.

At first sight, it seems to make more sense to infer pt_present_flag[0] to be equal to 1.

[vdrugeon]

Ticket #695 has been marked as a duplicate of this ticket.

[yk]

Good catch! Thanks! Fixed in an editorial input prepared by the editors.