Issue with conditions to derive trTypeHor and trTypeVer

[vdrugeon]

In 8.7.4.1 General, the following conditions seem strange, because the if conditions and the otherwise that follows use completely different syntax elements and variables:
"if implicitMtsEnabled is equal to 1, the following applies:

– If IntraSubPartitionsSplitType is not equal to ISP_NO_SPLIT or sps_explicit_mts_intra_enabled_flag is equal to 0 and CuPredMode[ 0 ][ xTbY ][ yTbY ] is equal to MODE_INTRA, trTypeHor and trTypeVer are derived as follows:
trTypeHor = ( nTbW >= 4 && nTbW <= 16 ) ? 1 : 0 (8 960)
trTypeVer = ( nTbH >= 4 && nTbH <= 16 ) ? 1 : 0 (8 961)
– Otherwise (cu_sbt_flag is equal to 1), trTypeHor and trTypeVer are specified in Table 8 15 depending on cu_sbt_horizontal_flag and cu_sbt_pos_flag."

Please check!
In case it is intended (i.e. (cu_sbt_flag equal to 1) is equivalent to !(IntraSubPartitionsSplitType is not equal to ISP_NO_SPLIT or sps_explicit_mts_intra_enabled_flag is equal to 0 and CuPredMode[ 0 ][ xTbY ][ yTbY ] is equal to MODE_INTRA) ), a note explaining why that is so would be helpful (because it really does not seem obvious).

[bbross]

Thanks for reporting and I agree that this is weird and probably a leftover from previous designs.

The easiest fix is to make it If SBT ... Otherwise ( !SBT)...

This will be fixed JVET-P2001-vC.