JP-7856728-B2 - Intra-predictive mode information propagation for geometric partition modes using IBC and intra-prediction

JP7856728B2JP 7856728 B2JP7856728 B2JP 7856728B2JP-7856728-B2

Inventors

リェン－フェイ・チェン
シアン・リ
シャン・リュウ

Assignees

テンセント・アメリカ・エルエルシー

Dates

Publication Date: 20260511
Application Date: 20241105
Priority Date: 20220829

Claims (12)

A video encoding method performed by a video encoder, A step of dividing the current block in the current picture of a video into at least a first partition and a second partition based on geometric partitioning mode (GPM), wherein the first partition is associated with intrablock copy (IBC) prediction mode and the second partition is associated with intraprediction mode, A step of storing prediction mode information for a first subblock among a plurality of subblocks of the current block, wherein the prediction mode information includes one of DC mode, Planar mode, and intra-prediction mode, based on whether the first subblock is associated with the IBC prediction mode, the intra-prediction mode, and one of both the IBC prediction mode and the intra-prediction mode. A step of encoding the current block and generating encoded information for the current block, wherein the encoded information indicates that the current block is divided into a first partition and a second partition based on the GPM, and the encoded current block and the generated encoded information are included in the video bitstream to be encoded. Methods that include...
The step of deriving the most likely mode (MPM) of the adjacent blocks of the current block using the stored prediction mode information. The method according to claim 1, further comprising:
If the first subblock is associated with the IBC prediction mode, the step of storing the prediction mode information includes storing only the Planar mode in the prediction mode information of the first subblock among the plurality of subblocks of the current block. The method according to claim 1.
If the first subblock is associated with the intra-prediction mode, the step of storing the prediction mode information includes storing only the intra-prediction mode in the prediction mode information of the first subblock among the plurality of subblocks of the current block. The method according to claim 1.
If the first subblock is associated with both the IBC prediction mode and the intra prediction mode, the step of storing the prediction mode information includes storing only the intra prediction mode in the prediction mode information of the first subblock among the plurality of subblocks of the current block. The method according to claim 1.
If the first partition of the current block is associated with the IBC prediction mode and the second partition of the current block is associated with the intra prediction mode, the step of storing the DC mode for each of the plurality of subblocks of the current block. The method according to claim 1, further comprising:
If the first partition of the current block is associated with the IBC prediction mode and the second partition of the current block is associated with the intra prediction mode, the step of storing the Planar mode for each of the plurality of subblocks of the current block. The method according to claim 1, further comprising:
If the first partition of the current block is associated with the IBC prediction mode and the second partition of the current block is associated with the intra prediction mode, the step of storing the intra prediction mode for each of the plurality of subblocks of the current block. The method according to claim 1, further comprising:
The method according to claim 2, wherein the prediction mode information of the first subblock among the plurality of subblocks of the current block is a propagating intramode for the MPM derivation of the adjacent block of the current block, and the adjacent block is predicted by the IBC prediction mode.
An apparatus comprising a processing circuit configured to perform the method described in any one of claims 1 to 9.
A computer program for causing at least one processor to perform the method described in any one of claims 1 to 9.
A video encoding method performed by a video encoder, A step of generating a video bitstream, A step of dividing the current block in the current picture of a video into at least a first partition and a second partition based on geometric partitioning mode (GPM), wherein the first partition is associated with intrablock copy (IBC) prediction mode and the second partition is associated with intraprediction mode, A step of storing prediction mode information for a first subblock among a plurality of subblocks of the current block, wherein the prediction mode information includes one of DC mode, Planar mode, and intra-prediction mode, based on whether the first subblock is associated with the IBC prediction mode, the intra-prediction mode, and one of both the IBC prediction mode and the intra-prediction mode. A step of encoding the current block and generating encoded information for the current block, wherein the encoded information indicates that the current block is divided into a first partition and a second partition based on the GPM, and includes the encoded current block and the generated encoded information in the video bitstream to be encoded. The steps include generating a video bitstream, A step of storing the encoded video bitstream, including, method.

Description

Cross-reference of related applications This application claims priority to U.S. Patent Application No. 17/898,447, “INTRA PREDICTION MODE INFORMATION PROPAGATION FOR GEOMETRIC PARTITION MODE WITH IBC AND INTRA PREDICTION,” filed on 29 August 2022, which in turn claims priority to U.S. Provisional Application No. 63/239,221, “INTRA PREDICTION MODE INFORMATION PROPAGATION FOR GEOMETRIC PARTITION MODE WITH IBC AND INTRA PREDICTION,” filed on 31 August 2021. The applicant claims priority rights to the "Prediction." The disclosures of prior applications are incorporated herein by reference in their entirety. This disclosure generally describes embodiments related to video coding. The background art descriptions provided herein are intended to provide a general overview of the context of this disclosure. The work of the inventors named herein, to the extent described in this background art section, and any aspects of the descriptions that might otherwise not qualify as prior art at the time of filing, are not expressly or implicitly recognized as prior art to this disclosure. Uncompressed digital images and/or videos can consist of a series of pictures, each picture having a spatial dimension of, for example, 1920 x 1080 luminance samples and associated saturation samples. The series of pictures may have a fixed or variable picture rate (informally also known as frame rate), for example, 60 pictures per second or 60 Hz. Uncompressed images and/or videos have specific bitrate requirements. For example, 1080p60 4:2:0 video with 8 bits per sample (1920 x 1080 luminance sample resolution at a frame rate of 60 Hz) requires a bandwidth of nearly 1.5 Gbit/s. One hour of such video requires more than 600 GB of storage space. One purpose of image and/or video coding and decoding may be to reduce the redundancy of input image and/or video signals through compression. Compression can help reduce the aforementioned bandwidth and/or storage space requirements by two orders of magnitude or more, in some cases. While this description uses video coding/decoding as an example for illustrative purposes, the same techniques can be applied to image coding/decoding in a similar manner without departing from the spirit of this disclosure. Both lossless and lossy compression, as well as combinations thereof, can be employed. Lossless compression refers to techniques that allow for the reconstruction of an exact copy of the original signal from the compressed original signal. When using lossy compression, the reconstructed signal may not be identical to the original signal, but the distortion between the original and reconstructed signals is small enough to make the reconstructed signal useful for its intended purpose. In the case of video, lossy compression is widely employed. The amount of acceptable distortion depends on the application; for example, users of certain consumer streaming applications may tolerate higher distortion than users of television distribution applications. The feasible compression ratio can reflect that a higher tolerance for distortion can lead to a higher compression ratio. Video encoders and decoders can utilize techniques from several broad categories, including, for example, motion compensation, transformation processing, and entropy coding. Video codec techniques may include a technique known as intra-coding. In intra-coding, sample values are represented without referencing samples or other data from a previously reconstructed reference picture. In some video codecs, the picture is spatially subdivided into blocks of samples. When all blocks of samples are coded in intra-mode, the picture can be an intra-picture. Intra-pictures, and their derivatives such as independent decoder refresh pictures, can be used to reset the decoder state and can therefore be used as the first picture in a coded video bitstream and video session, or as a still image. Samples in intra-blocks can undergo transformations, and the transformation coefficients can be quantized before entropy coding. Intra-prediction can be a technique to minimize the sample values in the pre-transformation region. In some cases, smaller post-transformation DC values and smaller AC coefficients result in fewer bits being required at a given quantization step size to represent the post-entropy-coded block. For example, conventional intra-coding used in MPEG-2 generation coding techniques does not use intra-prediction. However, some newer video compression techniques include methods that attempt to perform predictions based on surrounding sample data and/or metadata acquired during data block encoding/decoding. Such techniques will hereafter be referred to as “intra-prediction” techniques. It should be noted that, in at least some cases, intra-prediction uses only reference data from the current picture being reconstructed, and not from the reference picture itself. Intra-prediction can take many different forms. If two or more of these techniques c