Patent ID: 11902529
Assignee: BYTEDANCE INC.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 16:
17. 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 that a cross-component linear model (CCLM) prediction mode is applied to a first chroma block of a first video picture of the video,
determining, a parameter of a CCLM for the first chroma block according to a rule,
deriving, in the CCLM prediction mode, prediction samples of the first chroma block based on the CCLM and parameters of the CCLM, and
generating the bitstream based on prediction samples of the first chroma block,
wherein the rule specifies that the parameter of the CCLM is determined based on neirghbouring chroma samples of the first chroma block and first variables representing neighbouring luma samples of a first luma block corresponding to the first chroma block,
wherein the rule further specifies that the first variables are set equal to neighbouring luma samples of the first luma block when a value of a second variable indicates that a neighbouring block is available and are set equal to valid samples when the value of the second variable indicates the neighbouring block is not available,
wherein when the value of the second variable indicates the neighbouring block is available, the first variables denoted as pY [x] [y] are set equal to a reconstructed neighbouring above luma sample prior to a deblocking filter process at a location (xTbY+x, yTbY+y), and a maximum of x is equal to SubWidthC*Max(numSampT, nTbW)−1,
where (xTbY, yTbY) denotes a top-left position of the first luma block, x and y are integers, nTbW denotes a width of the first chroma block, SubWidthC is a width scale factor obtained according to a chroma format of the first video picture, and numSampT denotes a number of available neighbouring chroma samples in the CCLM prediction mode,
wherein the neighbouring block indicated by the second variable is a neighbouring chroma block covering a neighbouring above location of the first luma block.