KR-20260068003-A - METHOD FOR VIDEO ENCODING AND DECODING BASED ON INTRA PREDICTION FOR CHROMA BLOCKS

KR20260068003AKR 20260068003 AKR20260068003 AKR 20260068003AKR-20260068003-A

Abstract

A video decoding method according to an embodiment of the present invention for solving the aforementioned technical problem may include: a step of obtaining in-frame prediction mode information of a current color block from a bit sequence; a step of identifying illumination blocks at a plurality of locations corresponding to the current color block, wherein the plurality of locations include at least one of the center location, upper-left location, upper-right location, lower-left location, and lower-right location of the current color block; a step of obtaining an in-frame prediction mode from at least one of the identified illumination blocks and including it in a candidate list of in-frame prediction modes for the current color block; a step of obtaining an in-frame prediction mode from at least one color block spatially adjacent to the current color block and including it in the candidate list; a step of determining an in-frame prediction mode of the current color block based on the configured candidate list and the obtained in-frame prediction mode information; and a step of generating a prediction block for the current color block using the determined in-frame prediction mode.

Inventors

류창우
이선영

Assignees

가온그룹 주식회사
주식회사 아틴스

Dates

Publication Date: 20260513
Application Date: 20251104
Priority Date: 20241106

Claims (20)

In a video decoding method, A step of obtaining in-screen prediction mode information of the current color block from a bit sequence; A step of identifying illumination blocks at a plurality of positions corresponding to the current color block, wherein the plurality of positions include at least one of the center position, upper-left position, upper-right position, lower-left position, and lower-right position of the current color block; A step of obtaining an in-screen prediction mode from at least one of the identified illuminance blocks and including it in a list of in-screen prediction mode candidates for the current color block; A step of obtaining an in-screen prediction mode from at least one color block spatially adjacent to the current color block and including it in the candidate list; A step of determining an in-screen prediction mode of the current color block based on the above-configured candidate list and the above-acquired in-screen prediction mode information; and A video decoding method comprising the step of generating a prediction block for the current color block using the above-determined in-screen prediction mode.
In Article 1, The step of identifying illumination blocks at the plurality of locations above is, An image decoding method characterized by being performed when the above image is divided into a dual tree structure.
In Article 2, Acquiring an in-screen prediction mode from the above illumination blocks is, An image decoding method characterized by applying priority in the order of center position, top-left position, top-right position, bottom-left position, and bottom-right position, and checking the next position when the illumination block of the previous position is not available.
In Paragraph 3, The in-screen prediction mode of the illuminance block included in the above candidate list is, A video decoding method characterized by being limited to a maximum of five different intra-frame prediction modes.
In Article 1, A video decoding method further comprising the step of obtaining an in-frame prediction mode from non-adjacent color blocks that are not spatially adjacent to the current color block and including it in the candidate list.
In Article 5, The step of obtaining an in-screen prediction mode from the above non-adjacent color blocks is: An image decoding method characterized by prioritizing the most frequently used in-frame prediction mode and applying a weight inversely proportional to the distance from the current color block.
In Article 1, A video decoding method further comprising the step of including a recently used in-frame prediction mode stored in a buffer of a FIFO (First In First Out) structure in the candidate list.
In Article 1, The above adjacent color blocks are, A video decoding method characterized by including at least one of the positions left A1, left A0, upper B1, upper B0, and upper-left B2, and checking the availability of each position to obtain only the in-frame prediction mode of the available block.
In Article 1, Constituting the above candidate list is, A video decoding method characterized by excluding modes that overlap with already included modes and limiting the maximum number of candidate lists to one of 8, 16, or 32.
In Article 1, The prediction mode information within the screen above is, An image decoding method characterized by parsing as an index for the above-mentioned candidate list, decoding the first bin of the index as a context model and the remaining bins as a bypass mode.
In a video encoding method, A step of identifying illumination blocks at a plurality of positions corresponding to a current color block, wherein the plurality of positions include at least one of the center position, upper-left position, upper-right position, lower-left position, and lower-right position of the current color block; A step of obtaining an in-screen prediction mode from at least one of the identified illuminance blocks and including it in a list of in-screen prediction mode candidates for the current color block; A step of obtaining an in-screen prediction mode from at least one color block spatially adjacent to the current color block and including it in the candidate list; A step of selecting an in-screen prediction mode for the current color block from the above-configured candidate list; A step of generating a prediction block for the current color block using the prediction mode within the selected screen; and A video encoding method comprising the step of encoding information representing a prediction mode within the selected screen into a bit sequence.
In Article 11, The step of identifying illumination blocks at the plurality of locations above is, An image encoding method characterized by being performed when the above image is divided into a double tree structure.
In Article 11, A video encoding method further comprising the step of obtaining an in-frame prediction mode from surrounding color blocks that are not spatially adjacent to the current color block and including it in the candidate list.
In Article 11, The step of selecting a prediction mode within the above screen is, An image encoding method characterized by selecting an optimal mode from the above candidate list through rate-distortion optimization.
In Article 11, A video encoding method further comprising the step of reordering the above-described candidate list based on the Sum of Absolute Transformed Differences (SATD) value.
In a video decoding device, A parser configured to obtain in-screen prediction mode information of the current color block from a bit sequence; A candidate list configuration unit configured to identify illumination blocks at multiple locations corresponding to the current color block, obtain an in-screen prediction mode from at least one of the identified illumination blocks and include it in an in-screen prediction mode candidate list, and obtain an in-screen prediction mode from at least one color block spatially adjacent to the current color block and include it in the candidate list; A mode determination unit configured to determine the in-screen prediction mode of the current color block based on the above-configured candidate list and the above-acquired in-screen prediction mode information; and Including an in-screen prediction unit configured to generate a prediction block for the current color block using the in-screen prediction mode determined above; An image decoding device comprising at least one of the above plurality of positions, the center position, the top-left position, the top-right position, the bottom-left position, and the bottom-right position of the current color block.
In Article 16, The above candidate list composition section is, An image decoding device characterized by identifying illumination blocks at multiple locations when the above image is divided into a double tree structure.
In Article 16, The above candidate list composition section is, An image decoding device characterized by being further configured to acquire an in-frame prediction mode from surrounding color blocks that are not spatially adjacent to the current color block and include it in the candidate list.
In Article 16, It further includes a FIFO buffer section that stores the recently used in-screen prediction mode, and An image decoding device characterized in that the above candidate list configuration unit obtains an in-frame prediction mode from the above FIFO buffer unit and includes it in the above candidate list.
In Article 16, The above candidate list composition section is, An image decoding device characterized by being configured to limit the maximum number of candidate lists while excluding modes that overlap with already included modes.

Description

Method for Video Encoding and Decoding Based on Intra-Primary Prediction for Chroma Blocks The present invention relates to the field of encoding and decoding of digital video, and to a method for encoding and decoding digital video, a method for recording such data, and components, devices, and systems for realizing such a method. The present invention may correspond to a technical field identical to at least one of the digital video compression technology standards known by standard names such as MPEG-2, MPEG-4 Video, H.263, H.264/AVC, H.265/HEVC, H.266/VVC, VC-1, AV1, QuickTime, VP-9, VP-10, and Motion JPEG, a technical field for improving the inherent efficiency of the standard, or a technical field for improving or replacing the standard. Digital video encoding and decoding are widely utilized in various digital video applications. For example, devices such as video recording equipment and camcorders used for video recording activities—including digital television broadcasting, video transmission via communication networks, video calls, video conversations, and video chats, recording and provision of video content using optical media such as VCDs (video compact discs), DVDs (digital versatile discs), and Blu-rays, all procedures for the production, editing, collection, and distribution of video content, and video recording for personal, commercial, industrial, and security purposes—are all dependent on video encoding and decoding technology. Accordingly, embodiments that can be referred to as digital video encoders and decoders may constitute a part of a wide range of devices related to the creation, recording, and provision of digital video, including digital television, digital broadcasting systems, wireless broadcasting systems, computers in the form of notebooks/desktops/tablets, e-book readers, digital cameras, digital recording devices, digital multimedia playback devices, video game devices/terminals/consoles, mobile phones equipped with multimedia playback functions (including smartphones), equipment for video conferencing, and other devices. Digital video encoders and decoders as described above can be implemented by digital video compression standards that are understood by and widely used by people skilled in the art. The digital video compression standards may include at least one of the compression standards known by standard names such as MPEG-2, MPEG-4 Video, H.263, H.264/AVC, H.265/HEVC, H.266/VVC, VC-1, AV1, QuickTime, VP-9, VP-10, and Motion JPEG. Video encoders and decoders can be implemented to encode or decode digital video information more efficiently while complying with the above specifications, or by improving or modifying them. Attempts to modify the above specifications may also lead to the development of new specifications. Among well-known examples is the so-called enhanced compression model (ECM), which is an attempt to improve and replace the conventional H.266/VVC specifications, currently being developed by the Joint Video Experts Team (JVET), a joint international standardization group of ISO, IEC, and ITU-T. FIG. 1 is a conceptual diagram of a video communication system according to an embodiment of the present invention, FIG. 2 is a conceptual diagram of the arrangement of an encoder and a decoder in a real-time video streaming environment according to an embodiment of the present invention. FIG. 3 is a conceptual diagram of a functional unit of a video decoder according to an embodiment of the present invention, FIG. 4 is a conceptual diagram of a functional unit of a video encoder according to an embodiment of the present invention, FIG. 5 is a conceptual diagram of a frame type according to an embodiment of the present invention, FIG. 6 is a conceptual diagram showing the structure of a video encoder according to another embodiment of the present invention, FIG. 7 is a conceptual diagram illustrating a directional prediction mode of VVC according to an embodiment of the present invention. FIG. 8 is a conceptual diagram showing the concepts of a single tree and a dual tree according to an embodiment of the present invention. FIG. 9 is a conceptual diagram showing a position within an illuminance block corresponding to a color block in one embodiment of the present invention, FIG. 10 is an exemplary diagram of spatially adjacent candidate locations in one embodiment of the present invention, and FIG. 11 is an example of spatially non-adjacent candidate locations in one embodiment of the present invention. The present invention is capable of various modifications and may have various embodiments, and specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the invention to specific embodiments, and it should be understood that the invention includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention. Terms such as "first," "second," etc., may be used to d