Reference sample memory reuse for intra picture block compensation

A method of video encoding, the method comprising:

• when a reference block located in a picture for a current block located in the picture is located in a different coding tree unit (CTU) than a CTU of the current block,
• determining whether a CTU size of the CTU of the current block is smaller than a size of a reference sample memory;
• and
• when the CTU size of the CTU of the current block is determined to be smaller than the size of the reference sample memory,
• (i) determining whether a distance between the different CTU of the reference block and the CTU of the current block is smaller than a threshold, the threshold being based on a ratio of the size of the reference sample memory and the CTU size of the CTU of the current block, and the threshold being based on ((the size of the reference sample memory/the CTU size)−1)×(a CTU width of the CTU of the current block);
• and
• (ii) when the distance is determined to be smaller than the threshold, retrieving one or more samples based on a memory location of the reference sample memory to encode the current block.

A non-transitory computer-readable storage medium storing instructions which, when executed by a processor, cause the processor to perform a method of video encoding comprising:

• when a reference block located in a picture for a current block located in the picture is located in a different coding tree unit (CTU) than a CTU of the current block,
• determining whether a CTU size of the CTU of the current block is smaller than a size of a reference sample memory;
• and
• when the CTU size of the CTU of the current block is determined to be smaller than the size of the reference sample memory,
• (i) determining whether a distance between the different CTU of the reference block and the CTU of the current block is smaller than a threshold, the threshold being based on a ratio of the size of the reference sample memory and the CTU size of the CTU of the current block, and the threshold being based on ((the size of the reference sample memory/the CTU size)−1)×(a CTU width of the CTU of the current block);
• and
• (ii) when the distance is determined to be smaller than the threshold, retrieving one or more samples based on a memory location of the reference sample memory to encode the current block into a bitstream;
• and
• transmitting the encoded bitstream.