Image encoding and decoding method and apparatus generating an angular intra prediction mode

Patent metadata

Field	Value
Publication number	US-12075057-B2
Application number	US-202318471371-A
Country	US
Kind code	B2
Filing date	Sep 21, 2023
Priority date	Sep 28, 2017
Publication date	Aug 27, 2024
Grant date	Aug 27, 2024

Abstract

Provided is an image decoding method including: generating an intra prediction value of a current sample based on a position of the current sample in a current block and an intra prediction mode of the current block; determining a sample value of at least one filtering reference sample to be filtered and a first weight with respect to the filtering reference sample and a second weight with respect to the intra prediction value of the current sample; generating a filtered prediction sample value of the current sample based on the determined sample value of the filtering reference sample to be filtered, the intra prediction value of the current sample, the first weight with respect to the filtering reference sample, and the second weight with respect to the intra prediction value of the current sample; and generating a prediction block of the current block including the filtered prediction sample value.

First claim

The invention claimed is:

1. An image decoding method, comprising:
obtaining an intra prediction sample of a current sample in a current block using a first reference sample corresponding to the current sample, wherein the first reference sample is determined based on a position of the current sample and an intra prediction mode of the current block;
when the intra prediction mode of the current block is a first angular mode with one among upper prediction directions including a upper-right prediction direction, determining a second reference sample from among a plurality of reference samples in a left side of the current block based on the position of the current sample and the first angular mode, determining a second weight for the second reference sample based on a X-coordinate of the position of the current sample, and obtaining a modified intra prediction sample of the current sample based on the second reference sample, the intra prediction sample of the current sample, the second weight for the second reference sample and a first weight for the intra prediction sample of the current sample;
when the intra prediction mode of the current block is a second angular mode with one among left prediction directions including a lower-left prediction direction, determining a third reference sample from among a plurality of reference samples in an upper side of the current block based on the position of the current sample and the second angular mode, determining a third weight for the third reference sample based on a Y-coordinate of the position of the current sample, and obtaining a modified intra prediction sample of the current sample based on the third reference sample, the intra prediction sample of the current sample, the third weight for the third reference sample and the first weight for the intra prediction sample of the current sample; and
reconstructing the current block using the modified intra prediction sample of the current sample and a residual sample of the current sample,
wherein the first weight is determined based on at least one of the second weight and the third weight.

2. An image encoding method, comprising:
obtaining an intra prediction sample of a current sample in a current block using a first reference sample corresponding to the current sample, wherein the first reference sample is determined based on a position of the current sample and an intra prediction mode of the current block;
when the intra prediction mode of the current block is a first angular mode with one among upper prediction directions including a upper-right prediction direction, determining a second reference sample from among a plurality of reference samples in a left side of the current block based on the position of the current sample and the first angular mode, determining a second weight for the second reference sample based on a X-coordinate of the position of the current sample, and obtaining a modified intra prediction sample of the current sample based on the second reference sample, the intra prediction sample of the current sample, the second weight for the second reference sample and a first weight for the intra prediction sample of the current sample;
when the intra prediction mode of the current block is a second angular mode with one among left prediction directions including a lower-left prediction direction, determining a third reference sample from among a plurality of reference samples in an upper side of the current block based on the position of the current sample and the second angular mode, determining a third weight for the third reference sample based on a Y-coordinate of the position of the current sample, and obtaining a modified intra prediction sample of the current sample based on the third reference sample, the intra prediction sample of the current sample, the third weight for the third reference sample and the first weight for the intra prediction sample of the current sample; and
encoding the current block using the modified intra prediction sample of the current sample,
wherein the first weight is determined based on at least one of the second weight and the third weight.

3. A non-transitory computer-readable medium for recording a bitstream, the bitstream comprising:
an encoded data of a current block,
wherein the encoded data of the current block is obtained by:
obtaining an intra prediction sample of a current sample in the current block using a first reference sample corresponding to the current sample, wherein the first reference sample is determined based on a position of the current sample and an intra prediction mode of the current block;
when the intra prediction mode of the current block is a first angular mode with one among upper prediction directions including a upper-right prediction direction, determining a second reference sample from among a plurality of reference samples in a left side of the current block based on the position of the current sample and the first angular mode, determining a second weight for the second reference sample based on a X-coordinate of the position of the current sample, and obtaining a modified intra prediction sample of the current sample based on the second reference sample, the intra prediction sample of the current sample, the second weight for the second reference sample and a first weight for the intra prediction sample of the current sample;
when the intra prediction mode of the current block is a second angular mode with one among left prediction directions including a lower-left prediction direction, determining a third reference sample from among the plurality of reference samples in an upper side of the current block based on the position of the current sample and the second angular mode, determining a third weight for the third reference sample based on a Y-coordinate of the position of the current sample, and obtaining a modified intra prediction sample of the current sample based on the third reference sample, the intra prediction sample of the current sample, the third weight for the third reference sample and the first weight for the intra prediction sample of the current sample; and
encoding the current block using the modified intra prediction sample of the current sample,
wherein the first weight is determined based on at least one of the second weight and the third weight.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Choi Na-Rae
• Jin Bo-Ra
• Park Min-Woo

Classifications

• H04N19/159

  Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction · CPC title

• H04N19/132 Primary

  Sampling, masking or truncation of coding units, e.g. adaptive resampling, frame skipping, frame interpolation or high-frequency transform coefficient masking · CPC title

• H04N19/635

  characterised by filter definition or implementation details · CPC title

• H04N19/189

  characterised by the adaptation method, adaptation tool or adaptation type used for the adaptive coding · CPC title

• H04N19/176

  the region being a block, e.g. a macroblock · CPC title