JVET-AO0211 On colour mapping SEI message [J. Samuelsson-Allendes, S. Deshpande (Sharp)]

This input contribution relates to the colour mapping SEI message in the TuC for VSEI. The following items are proposed:

1. Add usage of displayBitDepth also for polynomial colour maps (in addition to piecewise linear colour maps).
2. Add clipping operation to pseudo code for polynomial form.
3. Rewrite of the function for piecewise linear colour maps to operate with integers only, while at the same time preserving as high precision as possible.

In item 1, in addition to use of displayBitDepth adds a rounding offset for polynomials.

A question was raised if there should also be a rounding offset for the piecewise linear process.

Item 1 was agreed.

For item 2, see notes on JVET-AO0202.

For item 3, the current design has a mix of fixed and floating point math for piecewise linear and this proposes to do only fixed point math.

Item 3 was agreed.

JVET-AO0211 On colour mapping SEI message

Localization and mapping (LAM) SEI: