JP-2026075550-A - Image decoding device, image decoding method, and program

Abstract

[Problem] To provide an image decoding device, an image decoding method, and a program that improve coding efficiency. [Solution] The image decoding device 200 includes an interframe prediction unit 206 that generates interframe prediction pixels for a block to be decoded. The interframe prediction unit 206 generates interframe prediction pixels by weighting together a reference pixel referenced by the motion vector of the block to be decoded and a reference pixel in the vicinity of the reference block referenced by the block vector of the adjacent block, when an interframe prediction is applied to the block to be decoded and the adjacent block has a block vector. [Selection Diagram] Figure 1

Inventors

• 木谷 佳隆
• 加藤 晴久
• 河村 圭

Assignees

• ＫＤＤＩ株式会社

Dates

Publication Date

20260508

Application Date

20241022

Claims (5)

1. An image decoding device, It includes an inter-frame prediction unit that generates inter-frame prediction pixels for the block to be decoded, The image decoding apparatus is characterized in that, when the interframe prediction unit applies interframe prediction to the block to be decoded and the adjacent block of the block to be decoded has a block vector, it generates the interframe prediction pixels by weighting the reference pixels referenced by the motion vector of the block to be decoded and the reference pixels in the vicinity of the reference block referenced by the block vector of the adjacent block.
2. The image decoding apparatus according to claim 1, characterized in that the unit to which the weighted average is applied is a plurality of sub-block units within the block to be decoded.
3. The image decoding apparatus according to claim 1, characterized in that at least one of the inter-frame prediction unit and the second intra-frame prediction unit applies the weighted average only to sub-blocks facing the boundary of the decoded block within the decoded block.
4. An image decoding method, The process includes step A, which generates interframe prediction pixels for the block to be decoded. An image decoding method characterized in that, in step A, interframe prediction is applied to the block to be decoded and adjacent blocks of the block to be decoded have block vectors, and the interframe prediction pixels are generated by weighting the reference pixels referenced by the motion vector of the block to be decoded and the reference pixels in the vicinity of the reference block referenced by the block vector of the adjacent block.
5. A program that makes a computer function as an image decoding device, The aforementioned image decoding device is It includes an inter-frame prediction unit that generates inter-frame prediction pixels for the block to be decoded, The interframe prediction unit is a program characterized in that, when an interframe prediction is applied to the block to be decoded and the adjacent block of the block to be decoded has a block vector, it generates the interframe prediction pixels by weighting the reference pixels referenced by the motion vector of the block to be decoded and the reference pixels in the vicinity of the reference block referenced by the block vector of the adjacent block.

Description

This invention relates to an image decoding device, an image decoding method, and a program. Non-Patent Documents 1 and 2 disclose interpretation and intrablock copying. Here, Non-Patent Document 2 discloses overlapping block motion compensation as an example of overlapping block weighted averaging for inter-prediction. Furthermore, Non-Patent Document 3 discloses a weighted average of overlapping blocks for intrablock copies. Furthermore, Non-Patent Document 4 discloses an application method for overlapping block weighted averaging as an extended example of interpretation, specifically when adjacent blocks are decoded using intraprediction. ITU-T H.266/VVCM. Coban et al., Algorithm description of Enhanced Compression Model 10 (ECM 10), JVET-AE2025, 2023.H. Kato et al., Extended Intra Block Copy with Adaptive Filtering and Overlapped Block Averaging, 2023 IEEE International Conference on Visual Communication and Image Processing (VCIP), 2023D. Kim et al., Non-EE2: OBMC extension with intra prediction, JVET-AI0154, 2024 Figure 1 shows an example of the functional block of an image decoding device 200 according to one embodiment.Figure 2 is a diagram illustrating the role of the inter-frame prediction unit 206.Figure 3 is a diagram illustrating AMVP.Figure 4 is a diagram illustrating the role of the second frame prediction unit 205.Figure 5 is a diagram illustrating the role of the second frame prediction unit 205.Figure 6 is a diagram illustrating BVP.Figure 7 shows an example of a weighted average of overlapping blocks.Figure 8 illustrates a case where interframe prediction is applied to the block to be decoded and intraframe prediction is applied to the adjacent block.Figure 9 illustrates the case where IntraTMP is applied to the block to be decrypted and IBC or IntraTMP is applied to the adjacent block.Figure 10 illustrates a case where IBC or IntraTMP is applied to the block to be decoded and interframe prediction is applied to the adjacent block.Figure 11 illustrates a case in which a second intra-frame prediction (or inter-frame prediction) is applied to the block to be decoded, and a first intra-frame prediction is applied to the adjacent block.Figure 12 illustrates an example of a modification in which a second in-frame prediction (or inter-frame prediction) is applied to the block to be decoded and a first in-frame prediction is applied to the adjacent block.Figure 13 illustrates an example of a weighted average of overlapping blocks at the subblock level.Figure 14 is a diagram illustrating an example of simplification when adjacent subblocks facing a block boundary are decoded by intra-prediction, inter-frame prediction, or second-frame prediction in the image decoding device 200 according to this embodiment.Figure 15 illustrates an example of a method for deriving an intra prediction mode using DIMD for overlapping block weighted averaging in the image decoding device 200 according to this embodiment.Figure 16 illustrates an example of a method for deriving an intra prediction mode using DIMD for overlapping block weighted averaging in the image decoding device 200 according to this embodiment.Figure 17 illustrates an example of a method for deriving an intra-prediction mode using DIMD for overlapping block weighted averaging in the image decoding device 200 according to this embodiment.Figure 18 illustrates an example of a method for deriving an intra-prediction mode using DIMD for overlapping block weighted averaging in the image decoding device 200 according to this embodiment. The embodiments of the present invention will be described below with reference to the drawings. Note that the components in the following embodiments can be replaced with existing components as appropriate, and various variations are possible, including combinations with other existing components. Therefore, the description of the following embodiments does not limit the content of the invention as described in the claims. <First Embodiment> The image decoding device 200 according to this embodiment will be described below with reference to Figures 1 to 18. The image decoding device 200 according to the first embodiment of the present invention is designed for a variety of image signals (hereinafter referred to as "images"). For example, the image decoding device 200 according to this embodiment is designed for YUV (YCbCr) images composed of luminance pixels and chrominance pixels, RGB images composed of RGB pixels, and monochrome images. Here, each pixel constituting an image has discrete values (pixel values) with a predetermined bit width. Furthermore, in the following descriptions of the functions of each part, the term "pixel" may refer to a block (unit) composed of pixels, a tree block (the largest block size), or a slice, tile, or image (picture) larger than a tree block. Figure 1 shows an example of the functional block of the image decoding device 200 according to this embodiment. As shown in Figure 1, the imag