Video encoder, a video decoder and corresponding methods

A non-transitory computer-readable storage medium storing programming for execution by a processing circuitry, wherein the programming, when executed by the processing circuitry, configures the processing circuitry to carry out a method comprising:

• determining whether a size of a current block is larger than a minimum allowed quadtree leaf node size;
• in response to determining that the size of the current block is not larger than the minimum allowed quadtree leaf node size, applying binary splitting to the current block based on a maximum allowed binary tree root node size, wherein the maximum allowed binary tree root node size is determined based on the minimum allowed quadtree leaf node size, and wherein the minimum allowed quadtree leaf node size is not larger than the maximum allowed binary tree root node size;
• and
• determining whether the current block is a boundary block;
• wherein the applying binary splitting to the current block comprises:
• in response to determining that the current block is a boundary block and the size of the current block is not larger than the minimum allowed quadtree leaf node size, applying binary splitting to the current block.

A coding device, comprising:

• one or more processors;
• and
• a non-transitory computer-readable storage medium coupled to the processors and storing programming for execution by the processors, wherein the programming, when executed by the processors, configures the coding device to carry out the method comprising:
• determining whether a size of a current block is larger than a minimum allowed quadtree leaf node size;
• in response to determining that the size of the current block is not larger than the minimum allowed quadtree leaf node size, applying binary splitting to the current block based on a maximum allowed binary tree root node size, wherein the maximum allowed binary tree root node size is determined based on the minimum allowed quadtree leaf node size, and wherein the minimum allowed quadtree leaf node size is not larger than the maximum allowed binary tree root node size;
• determining whether the current block is a boundary block;
• wherein the applying binary splitting to the current block comprises:
• in response to determining that the current block is a boundary block and the size of the current block is not larger than the minimum allowed quadtree leaf node size, applying binary splitting to the current block.

A non-transitory storage medium which includes an encoded bitstream, the bitstream being generated by dividing a current picture of a video signal or an image signal into a plurality blocks including a current block, and comprising a plurality of syntax elements, wherein the plurality of syntax elements comprises a first syntax element used to derive a minimum allowed quadtree leaf node size for the dividing, and a second syntax element used to derive a maximum allowed binary tree root node size based on the minimum allowed quadtree leaf node size for the dividing, wherein the minimum allowed quadtree leaf node size is not larger than the maximum allowed binary tree root node size;

• wherein the bitstream is being generated by further:
• determining whether the current block is a boundary block;
• and
• in response to determining that the current block is a boundary block and the size of the current block is not larger than the minimum allowed quadtree leaf node size, applying binary splitting to the current block.