US-20260129223-A1 - IMAGE DECODER AND IMAGE DECODING METHOD CAPABLE OF BLENDING OPERATION BETWEEN PARTITIONS

US20260129223A1US 20260129223 A1US20260129223 A1US 20260129223A1US-20260129223-A1

Abstract

An image decoder includes circuitry and a memory, wherein the circuitry, in operation, calculates first values of a first partition in a current block, using a first motion vector for the first partition; calculates second values of a second partition in the current block, using a second motion vector for the second partition; calculates third values of a set of pixels between the first partition and the second partition, using the first motion vector; calculates fourth values of the set of pixels, using the second motion vector; and weights the third values and the fourth values. A number of pixels in a row in the set of pixels is two or more, and two or more weights applied to the third values increase along the row.

Inventors

Kiyofumi Abe
Jing Ya LI
Takahiro Nishi
Tadamasa Toma
Ryuichi KANOH
Chong Soon Lim
Ru Ling LIAO
Hai Wei Sun
Sughosh Pavan SHASHIDHAR
Han Boon Teo

Assignees

PANASONIC INTELLECTUAL PROPERTY CORPORATION OF AMERICA

Dates

Publication Date: 20260507
Application Date: 20251219

Claims (3)

1 . An image encoder comprising: circuitry; and a memory coupled to the circuitry; wherein the circuitry, in operation: obtains a current block from a coding tree unit (CTU); calculates first values of pixels of a first partition in the current block, using a first motion vector for the first partition; calculates second values of pixels of a second partition in the current block, using a second motion vector for the second partition; calculates third values of a set of pixels between the first partition and the second partition, using the first motion vector; calculates fourth values of the set of pixels, using the second motion vector; weights the third values and the fourth values of the set of pixels; and encodes the current block using the weighted third values and the weighted fourth values, wherein only the third values and the fourth values of the set of pixels are weighted for the current block, wherein a number of pixels in a row in the set of pixels is greater than two, and greater than two weights applied to the third values of the set of pixels increase along the row in a first direction, and greater than two weights applied to the fourth values of the set of pixels decrease along the row in the first direction.
2 . An image decoder comprising: circuitry; and a memory coupled to the circuitry; wherein the circuitry, in operation: obtains a current block from a coding tree unit (CTU); calculates first values of pixels of a first partition in the current block, using a first motion vector for the first partition; calculates second values of pixels of a second partition in the current block, using a second motion vector for the second partition; calculates third values of a set of pixels between the first partition and the second partition, using the first motion vector; calculates fourth values of the set of pixels, using the second motion vector; weights the third values and the fourth values of the set of pixels; and decodes the current block using the weighted third values and the weighted fourth values, wherein only the third values and the fourth values of the set of pixels are weighted for the current block, wherein a number of pixels in a row in the set of pixels is greater than two, and greater than two weights applied to the third values of the set of pixels increase along the row in a first direction, and greater than two weights applied to the fourth values of the set of pixels decrease along the row in the first direction.
3 . A non-transitory computer readable medium storing a bitstream and a computer program, the bitstream including information according to which the computer program causes a decoder to perform a partition process, in the partition process: a current block is obtained from a coding tree unit (CTU); first values of pixels of a first partition in the current block are calculated using a first motion vector for the first partition; second values of pixels of a second partition in the current block are calculated using a second motion vector for the second partition; third values of a set of pixels between the first partition and the second partition are calculated using the first motion vector; fourth values of the set of pixels are calculated using the second motion vector; the third values and the fourth values of the set of pixels are weighted; and the current block is decoded using the weighted third values and the weighted fourth values, wherein only the third values and the fourth values of the set of pixels are weighted for the current block, wherein a number of pixels in a row in the set of pixels is greater than two, and greater than two weights applied to the third values of the set of pixels increase along the row in a first direction, and greater than two weights applied to the fourth values of the set of pixels decrease along the row in the first direction.

Description

TECHNICAL FIELD This disclosure relates to video coding, and particularly to video encoding and decoding systems, components, and methods for performing an inter prediction function to build a current block based on a reference frame or an intra prediction function to build a current block based on an encoded/decoded reference block in a current frame. BACKGROUND ART With advancement in video coding technology, from H.261 and MPEG-1 to H.264/AVC (Advanced Video Coding), MPEG-LA, H.265/HEVC (High Efficiency Video Coding) and H.266/VVC (Versatile Video Codec), there remains a constant need to provide improvements and optimizations to the video coding technology to process an ever-increasing amount of digital video data in various applications. This disclosure relates to further advancements, improvements and optimizations in video coding, particularly, in connection with an inter prediction function or an intra prediction function, splitting an image block into a plurality of partitions including at least a first partition having a non-rectangular shape (e.g., a triangle) and a second partition. SUMMARY OF INVENTION According to one aspect, an image decoder is provided which includes circuitry, and a memory coupled to the circuitry. The circuitry, in operation, performs a boundary smoothing operation along a boundary between a first partition having a triangular shape and a second partition having a triangular shape that are split from an image block. The boundary smoothing operation includes: first-predicting first values of a set of pixels of the first partition along the boundary, using a first motion vector for the first partition; second-predicting second values of the set of pixels of the first partition along the boundary, using a second motion vector for the second partition; weighting the first values and the second values; and decoding the first partition using the weighted first values and the weighted second values. According to another aspect, an image decoder is provided, which includes: an entropy decoder which, in operation, receives and decodes an encoded bitstream to obtain quantized transform coefficients; an inverse quantizer and transformer which, in operation, inverse quantizes the quantized transform coefficients to obtain transform coefficients and inverse transform the transform coefficients to obtain residuals; an adder which, in operation, adds the residuals outputted from the inverse quantizer and transformer and predictions outputted from a prediction controller to reconstruct blocks; and the prediction controller coupled to an inter predictor, an intra predictor, and a memory, wherein the inter predictor, in operation, generates a prediction of a current block based on a reference block in a decoded reference picture and the intra predictor, in operation, generates a prediction of a current block based on an decoded reference block in a current picture. The image decoder, in operation, performs a boundary smoothing operation along a boundary between a first partition having a triangular shape and a second partition having a triangular shape that are split from an image block. The boundary smoothing operation includes: first-predicting first values of a set of pixels of the first partition along the boundary, using a first motion vector for the first partition; second-predicting second values of the set of pixels of the first partition along the boundary, using a second motion vector for the second partition; weighting the first values and the second values; and decoding the first partition using the weighted first values and the weighted second values. According to another aspect, an image decoding method is provided for performing a boundary smoothing operation along a boundary between a first partition having a triangular shape and a second partition having a triangular shape that are split from an image block. The method includes generally four steps: first-predicting first values of a set of pixels of the first partition along the boundary, using a first motion vector for the first partition; second-predicting second values of the set of pixels of the first partition along the boundary, using a second motion vector for the second partition; weighting the first values and the second values; and decoding the first partition using the weighted first values and the weighted second values. According to one aspect, an image encoder is provided including circuitry and a memory coupled to the circuitry. The circuitry, in operation, performs a boundary smoothing operation along a boundary between a first partition having a non-rectangular shape and a second partition that are split from an image block. The boundary smoothing operation includes: first-predicting first values of a set of pixels of the first partition along the boundary, using information of the first partition; second-predicting second values of the set of pixels of the first partition along the boundary, using informat