Method and apparatus for cross-component prediction for video coding

A computer system, comprising:

• one or more processors;
• and
• one or more storage devices storing computer-executable instructions that, when executed, cause the one or more processors to:
• obtain a video block from a bitstream;
• obtain neighboring luma and chroma sample values of the video block;
• perform at least one pre-operation to the neighboring luma sample values and to internal luma sample values in the video block, to obtain pre-operated neighboring and internal luma sample values, wherein performing the at least one pre-operation comprises calculating sample differences based on the neighboring and internal luma sample values;
• derive a linear model by using the pre-operated neighboring luma sample values and the neighboring chroma sample values;
• predict each of internal chroma sample values in the video block by applying the linear model to one or more corresponding pre-operated internal luma sample values for that internal chroma sample value;
• and
• obtain decoded video block using the predicted internal chroma sample values.

A non-transitory computer readable storage medium, storing a bitstream that is to be decoded by performing the following steps:

• obtaining a video block from the bitstream;
• obtaining neighboring luma and chroma sample values of the video block;
• performing at least one pre-operation to the neighboring luma sample values and to internal luma sample values in the video block, to obtain pre-operated neighboring and internal luma sample values, wherein performing the at least one pre-operation comprises calculating sample differences based on the neighboring and internal luma sample values;
• deriving a linear model by using the pre-operated neighboring luma sample values and the neighboring chroma sample values;
• predicting each of internal chroma sample values in the video block by applying the linear model to one or more corresponding pre-operated internal luma sample values for that internal chroma sample value;
• and
• obtaining decoded video block using the predicted internal chroma sample values.