Method and system for selectively breaking prediction in video coding
Described are techniques in video coding and/or decoding that allow for selectively breaking prediction and/or in loop filtering across segment boundaries between different segments of a video picture. A high layer syntax element, such as a parameter set or a slice header, may contain one or more indications signalling to an encoder and/or decoder whether an associated prediction or loop filtering tool may be applied across the segment boundary. In response to such one or more indications, the encoder and/or decoder may then control the prediction or loop filtering tool accordingly.
1. An apparatus comprising:
a non-transitory computer-readable medium for storing image data, the computer-readable medium storing a bitstream, the bitstream including data representing:
a first slice and a second slice of a coded video picture,
wherein the first slice and the second slice are divided by at least one slice boundary,
wherein at least the first slice is divided by a tile boundary to belong to two tiles, and
wherein the two tiles do not have tile headers;
a parameter set including a first flag that enables a decoder to determine whether to apply a deblocking filter operation across the tile boundary; and
a slice header of the coded video picture including a second flag that enables the decoder to determine whether to apply a deblocking filtering operation across the at least one slice boundary;
wherein the first flag is different from the second flag,
wherein the slice boundary is different from the tile boundary, and
wherein applying a deblocking filter operation across a boundary comprises a derivation of a boundary strength of the boundary based on a prediction mode of a block, values of transform coefficients of the block, and a motion vector of the block.
2. The apparatus of claim 1 , wherein a tile is a rectangular group of multiple macroblocks within the coded video picture.