IMAGE ENCODING DEVICE, A METHOD FOR ENCODING AN IMAGE, A PROGRAM FOR THIS, AN IMAGE DECODING DEVICE, A METHOD FOR DECODING AN IMAGE AND A PROGRAM FOR THIS Russian patent published in 2019 - IPC H04N19/00 G06T9/00 H04N19/50 

FIELD: data processing.

SUBSTANCE: invention relates to encoding/decoding images. Decoding method comprises: decoding a first quantisation parameter for a first sub-block of encoded data associated with a first difference value between a first quantisation parameter for a first sub-block and a second quantisation parameter for a second sub-block, and encoded data associated with the second difference value between the third quantization parameter for the third sub-block and the value corresponding to the average quantisation parameter value for the sub-blocks in the block, wherein the first subunit, the second subunit and the third subunit are generated by dividing said block in order to form a quadrant tree; obtaining a second quantisation parameter based on a first quantisation parameter and a first difference value, and obtaining a third quantisation parameter based on a second difference value, decoded by said decoding, and a value corresponding to the average quantisation parameter value for the sub-blocks decoded to the third sub-block.

EFFECT: technical result consists in improvement of encoding and decoding speed.

1 cl, 23 dwg