Model parameter derivation for prediction modes based on least mean square optimization

A computing system, comprising:

• control circuitry;
• and
• memory storing one or more programs configured to be executed by the control circuitry, the one or more programs further comprising instructions for:
• receiving a video bitstream including a current block of a current frame, wherein the video bitstream includes a syntax element for a cross-component prediction (CCP) mode;
• when the syntax element indicates that the CCP mode is enabled:
• identifying a reference area for the current block;
• identifying samples of a subset of the reference area by downsampling the reference area;
• determining a plurality of model parameters for the CCP mode for a chroma sample of the current block using the subset of the reference area;
• and
• deriving the chroma sample for the current block by combining a set of one or more luma samples using the plurality of model parameters;
• and
• reconstructing the current frame including the chroma sample of the current block.

A method of video encoding, comprises:

• receiving video data comprising a current block of a current frame;
• encoding the current frame;
• transmitting the encoded current frame via a video bitstream;
• and
• signaling, via the video bitstream, a syntax element for a cross-component prediction (CCP) mode indicating whether to reconstruct a first chroma sample of the current block based on a first luma sample and a set of associated neighboring luma samples;
• wherein, when the CCP mode is enabled, a reference area of the current block is downsampled and applied to determine a plurality of model parameters used in the CCP mode.