Typo in derivation process of ctxInc for coeff_sign_flag

[wangyang.cs]

A typo exists in JVET-R2001-vA:
To derive ctxInc for coeff_sign_flag, “== 0” is forgotten in the conditions in (1597) and (1598).

Suggest changes in JVET-R2001-vA as follows:

9.3.4.2.10 Derivation process of ctxInc for the syntax element coeff_sign_flag for transform skip mode
Inputs to this process are the colour component index cIdx, the luma location ( x0, y0 ) specifying the top-left sample of the current transform block relative to the top-left sample of the current picture, the current coefficient scan location ( xC, yC )
Output of this process is the variable ctxInc.
The variables leftSign and aboveSign are derived as follows:

leftSign = ( xC = = 0 ) ? 0 : CoeffSignLevel[ xC − 1 ][ yC ] (1594)
aboveSign = ( yC = = 0 ) ? 0 : CoeffSignLevel[ xC ][ yC − 1 ] (1595)

The variable ctxInc is derived as follows:

– If leftSign is equal to 0 and aboveSign is equal to 0, or if leftSign is equal to −aboveSign, the following applies:

ctxInc = ( BdpcmFlag[ x0 ][ y0 ][ cIdx ] = = 0 ? 0 : 3 ) (1596)

– Otherwise, if leftSign is greater than or equal to 0 and aboveSign is greater than or equal to 0, the following applies:

ctxInc = ( BdpcmFlag[ x0 ][ y0 ][ cIdx ] = = 0 ? 1 : 4 ) (1597)

– Otherwise, the following applies:

ctxInc = ( BdpcmFlag[ x0 ][ y0 ][ cIdx ] = = 0 ? 2 : 5 ) (1598)

[bbross]

Good catch, thanks!

This will be fixed in first verison of D10.