Image encoding/decoding method using prediction block and apparatus for same

Patent metadata

Field	Value
Publication number	US-11711541-B2
Application number	US-202117202935-A
Country	US
Kind code	B2
Filing date	Mar 16, 2021
Priority date	Jun 20, 2011
Publication date	Jul 25, 2023
Grant date	Jul 25, 2023

Abstract

According to the present invention, an image encoding/decoding method comprises the steps of: performing an intra prediction on a current block so as to generate a prediction block; performing filtering on a filtering target pixel in the prediction block on the basis of the intra prediction mode of the current block so as to generate a final prediction block; and generating a reconstructed block on the basis of a reconstructed differential block corresponding to the current block and on the final prediction block. According to the present invention, image encoding/decoding efficiency can be improved.

First claim

The invention claimed is:

1. A method for video decoding, the method comprising:
generating a prediction block by performing intra prediction on a current block, and
generating a reconstructed block based on the prediction block and a reconstructed residual block corresponding to the current block,
wherein:
a prediction value of a prediction pixel of the prediction block is generated using a reference pixel during the intra prediction,
the prediction pixel is located in a vertical pixel line at a left side of the prediction block or a horizontal pixel line at an upper side of the prediction block,
the reference pixel is located in a vertical reference pixel line which adjacent to the left side of the prediction block,
a coefficient for the reference pixel is determined based on a size of the current block,
the prediction value of the prediction pixel is generated based on a product of the coefficient for the reference pixel and a pixel value of the reference pixel, and
the reference pixel is diagonally adjacent to a lower-left corner of the prediction block in a case that the prediction pixel is a lowermost and leftmost pixel in the prediction block.

2. The method of claim 1 , wherein an intra prediction mode of the intra prediction is a Planar mode, and
the prediction block is generated based on a filter using the reference pixel and an intermediate prediction pixel of an intermediate prediction block for the Planar mode.

3. The method of claim 2 , wherein whether or not to use the filter is determined based on a size of the current block.

4. The method of claim 2 , wherein the prediction pixel and the reference pixel are located on one horizontal line.

5. A method for video encoding, the method comprising:
generating a prediction block by performing intra prediction on a current block, and
generating a reconstructed block based on the prediction block and a reconstructed residual block corresponding to the current block,
wherein:
a prediction value of a prediction pixel of the prediction block is generated using a reference pixel during the intra prediction,
the prediction pixel is located in a vertical pixel line at a left side of the prediction block or a horizontal pixel line at an upper side of the prediction block, and
the reference pixel is located in a vertical reference pixel line which adjacent to the left side of the prediction block,
a coefficient for the reference pixel is determined based on a size of the current block,
the prediction value of the prediction pixel is generated based on a product of the coefficient for the reference pixel and a pixel value of the reference pixel, and
the reference pixel is diagonally adjacent to a lower-left corner of the prediction block in a case that the prediction pixel is a lowermost and leftmost pixel in the prediction block.

6. The method of claim 5 , wherein an intra prediction mode of the intra prediction is a Planar mode, and
the prediction block is generated based on a filter using the reference pixel and an intermediate prediction pixel of an intermediate prediction block for the Planar mode.

7. The method of claim 6 , wherein whether or not to use the filter is determined based on a size of the current block.

8. The method of claim 6 , wherein the prediction pixel and the reference pixel are located on one horizontal line.

9. A non-transitory computer-readable medium storing a bitstream, the bitstream comprising:
prediction mode information indicating an intra prediction mode for a current block, wherein
a prediction block is generated by performing intra prediction on the current block using the prediction mode information,
a reconstructed block is generated based on the prediction block and a reconstructed residual block corresponding to the current block,
a prediction value of a prediction pixel of the prediction block is generated using a reference pixel during the intra prediction,
the prediction pixel is located in a vertical pixel line at a left side of the prediction block or a horizontal pixel line at an upper side of the prediction block, and
the reference pixel is located in a vertical reference pixel line which adjacent to the let side of the prediction block,
a coefficient for the reference pixel is determined based on a size of the current block,
the prediction value of the prediction pixel is generated based on a product of the coefficient for the reference pixel and a pixel value of the reference pixel, and
the reference pixel is diagonally adjacent to a lower-left corner of the prediction block in a case that the prediction pixel is a lowermost and leftmost pixel in the prediction block.

10. The non-transitory computer-readable medium of claim 9 , wherein the intra prediction mode is a Planar mode, and
the prediction block is generated based on a filter using the reference pixels and an intermediate prediction pixel of an intermediate prediction block for the Planar mode.

11. The non-transitory computer-readable medium of claim 10 , wherein whether or not to use the filter is determined based on a size of the current block.

12. The non-transitory computer-readable medium of claim 10 , wherein the prediction pixel and the reference pixel are located on one horizontal line.

Assignees

• Electronics & Telecommunications Res Inst

Inventors

• Lee Jin Ho
• Kim Hui Yong
• Lim Sung Chang
• Choi Jin Soo
• Kim Jin Woong

Classifications

• H04N19/593 Primary

  involving spatial prediction techniques · CPC title

• H04N19/105

  Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction · CPC title

• H04N19/11

  among a plurality of spatial predictive coding modes · CPC title

• H04N19/117 Primary

  Filters, e.g. for pre-processing or post-processing (sub-band filter banks H04N19/635) · CPC title

• H04N19/122

  Selection of transform size, e.g. 8x8 or 2x4x8 DCT; Selection of sub-band transforms of varying structure or type · CPC title