Apparatus and method for coding an image

An image processing apparatus comprising:

• at least one processor;
• and
• a non-transitory computer-readable storage medium coupled to the at least one processor and storing programming instructions for execution by the at least one processor, wherein the programming instructions instruct the at least one processor to perform operations comprising:
• intra-predicting a block of an image based on reference samples of the image, wherein the reference samples are arranged in one or more reference sample sets, and each of the reference sample sets is a coherent set of reference samples and comprises one or more reference samples adjoining the block;
• segmenting each of the one or more reference sample sets into a sequence of three or more subsets, wherein the sequence of three or more subsets comprises a first subset, a last subset, and one or more intermediary subsets located between the first subset and the last subset;
• determining weight values of subsets of the reference samples of the image by determining a weight value for each subset in the sequence of three or more subsets corresponding to each of the one or more reference sample sets, wherein weight values of the one or more intermediary subsets are lower than weight values of the first subset and the last subset;
• fitting a plane to the reference samples of the image using the determined weight values of the subsets;
• and
• generating an intra-predicted block based on the plane.

An image coding method, comprising coding an image, wherein coding the image comprises:

• intra-predicting a block of the image based on reference samples of the image, wherein the reference samples are arranged in one or more reference sample sets, and each of the reference sample sets is a coherent set of reference samples and comprises one or more reference samples adjoining the block;
• segmenting each of the one or more reference sample sets into a sequence of three or more subsets, wherein the sequence of three or more subsets comprises a first subset, a last subset, and one or more intermediary subsets located between the first subset and the last subset;
• determining weight values of subsets of the reference samples of the image by determining a weight value for each subset in the sequence of three or more subsets corresponding to each of the one or more reference sample sets, weight values of the one or more intermediary subsets are lower than the weight values of the first subset and the last subset;
• fitting a plane to the reference samples of the image using the determined weight values of the subsets;
• and
• generating an intra-predicted block based on the plane.

A non-transitory computer-readable storage medium coupled to at least one processor and storing programming instructions for execution by the at least one processor, wherein the programming instructions instruct the at least one processor to perform operations comprising:

• intra-predicting a block of an image based on reference samples of the image, wherein the reference samples are arranged in one or more reference sample sets, and each of the reference sample sets is a coherent set of reference samples and comprises one or more reference samples adjoining the block;
• segmenting each of the one or more reference sample sets into a sequence of three or more subsets, wherein the sequence of three or more subsets comprises a first subset, a last subset, and one or more intermediary subsets located between the first subset and the last subset;
• determining weight values of subsets of the reference samples of the image by determining a weight value for each subset in the sequence of three or more subsets corresponding to each of the one or more reference sample sets, wherein weight values of the one or more intermediary subsets are lower than weight values of the first subset and the last subset;
• fitting a plane to the reference samples of the image using the determined weight values of the subsets;
• and
• generating an intra-predicted block based on the plane.