Patent ID: 11924472
Assignee: BEIJING BYTEDANCE NETWORK TECHNOLOGY CO., LTD.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 13:
14. A non-transitory computer-readable recording medium storing a bitstream of a video which is generated by a method performed by a video processing apparatus, wherein the method comprises:
determining, for a current chroma video block of a video, that a scaling process is applied on chroma residual samples of the current chroma video block; and
generating the bitstream by applying the scaling process on the chroma residual samples,
wherein in the scaling process, the chroma residual samples are scaled based on at least one scaling factor before being used to reconstruct the current chroma video block,
wherein one or multiple syntax elements and a bin index identifying a piece of a piecewise linear model are used to derive the at least one scaling factor, and the one or multiple syntax elements are conditionally signaled, wherein the one or multiple syntax elements indicating parameters for deriving the piecewise linear model are included in an adaptation parameter set;
wherein a syntax element indicative of selectively enabling or disabling the scaling process, when included in the bitstream, is included in a picture level associated with the current chroma video block; and
wherein deriving the bin index comprises:
checking an availability of one or more neighboring luma blocks of a video unit, which is determined based on a luma sample corresponding to a top-left sample of the current chroma video block;
determining, based on the availability of the one or more neighboring luma blocks, whether to retrieve the neighboring luma samples of the video unit, wherein the one or more neighboring luma blocks comprise the neighboring luma samples; and
deriving the bin index based on the averaged luma variable computed using the neighboring luma samples by a rounding-based average operation in case that the neighboring samples are available.