Indexing of IBC predSamples in Section 8.6.3

[bheng]

Since luma location ( xCb, yCb ) is a position within the picture, not the coding block, index [ x ][ y ] in the following equation will, in general, be completely outside of the (cbWidth x cbHeight) predSamples array.

predSamples[ x ][ y ] = ibcVirBuf[ 0 ][ xVb ][ yVb ] (1098)
with x = xCb..xCb + cbWidth - 1 and y = yCb..yCb + cbHeight - 1

The same is true for the chroma eqaution as well.

predSamples[ x ][ y ] = ibcVirBuf[ cIdx ][ xVb ][ yVb ] (1101)
with x = xCb / SubWidthC..xCb / SubWidthC + cbWidth / SubWidthC − 1 and y = yCb / SubHeightC..yCb / SubHeightC + cbHeight / SubHeightC − 1

[bbross]

Good catch thanks. I suggest to fix both as follows:

predSamples[ x − xCb ][ y − yCb ] = IbcVirBuf[ 0 ][ xVb ][ yVb ] (1098)

predSamples[ x − (xCb / SubWidthC) ][ y −(yCb / SubHeightC) ] = IbcVirBuf[ cIdx ][ xVb ][ yVb ] (1101)

[bbross]

Fixed as discussed/suggested in JVET-T0110-v2.