TW202232954A - Most probable modes for intra prediction for video coding - Google Patents

Abstract

A video coder may code a block of video data using an intra prediction mode determined from a most probable mode list. The video coder may construct a general most probable mode list containing N entries, wherein the N entries of the general most probable mode list are intra prediction modes, and wherein a planar mode is an ordinal first entry in the general most probable mode list, construct a primary most probable mode list from a first Np entries in the general most probable mode list, where Np is less than N, and construct a secondary most probable mode list from a remaining (N-Np) entries in the general most probable mode list. The video coder may then determine a current intra prediction mode for a current block of video data using the primary most probable mode list or the secondary most probable mode list.

Description

Most Likely Mode for In-Frame Prediction for Video Coding

This patent application claims the benefit of US Provisional Patent Application Serial No. 63/131,115, filed on December 28, 2020, the entire contents of which are incorporated herein by reference.

The content of this case is about video encoding and video decoding.

Digital video capabilities can be incorporated into a wide variety of devices, including digital televisions, digital broadcast systems, wireless broadcasting systems, personal digital assistants (PDAs), laptop or desktop computers, tablet computers, e-book readers devices, digital cameras, digital recording devices, digital media players, video game equipment, video game consoles, cellular or satellite radio telephones (so-called "smart phones"), video teleconferencing equipment, video streaming equipment, etc. Digital video equipment implementing video coding techniques (such as those described in MPEG-2, MPEG-4, ITU-T H.263, ITU-T H.264/MPEG-4 (Part 10, Advanced Video Coding (AVC)) , the standards defined by ITU-T H.265/High Efficiency Video Coding (HEVC) and their techniques described in extensions to such standards). By implementing such video decoding technology, video equipment can transmit, receive, encode, decode and/or store digital video information more efficiently.

Video coding techniques include spatial (intra-picture) prediction and/or temporal (inter-picture) prediction to reduce or remove redundancy inherent in video sequences. For block-based video coding, a video slice (eg, a video picture or a portion of a video picture) may be partitioned into video blocks, which may also be referred to as coding tree units (CTUs), coding units ( CU) and/or coding nodes. Video blocks in an intra-coded (I) slice of a picture are encoded using spatial prediction relative to reference samples in neighboring blocks in the same picture. Video blocks in an inter-frame-coded (P or B) slice of a picture may use spatial prediction relative to reference samples in neighboring blocks in the same picture, or relative to reference samples in other reference pictures time forecast. A picture may be referred to as a frame, and a reference picture may be referred to as a reference frame.

In general, techniques for determining a most probable mode (MPM) list for intra-frame prediction and determining an intra-frame prediction mode from the most probable mode list are described. The technique disclosed in this case can improve decoding efficiency when decoding video data using in-frame prediction. In particular, the subject matter describes techniques for constructing a general list of most probable patterns, and then constructing lists of primary and secondary most probable patterns from the general list of most probable patterns. The primary and secondary most probable mode lists may include intra-frame prediction modes from adjacent blocks and intra-frame prediction mode offsets from the intra-frame prediction modes of adjacent blocks. The techniques presented in this case can improve the efficiency of generating lists of major and minor most likely patterns.

In one example, a method includes the steps of constructing a general most probable mode list comprising N entries, wherein the N entries of the general most probable mode list are intra-frame prediction modes, and wherein the planar mode is the general most probable mode Sequential first entry in the list of possible modes; construct a list of primary most likely modes from the first Np entries in this list of general most probable modes, where Np is less than N; ) entries to construct a secondary most probable mode list; use the primary most probable mode list or the secondary most probable mode list to determine the current in-frame prediction mode for the current block of video data; and use the current in-frame prediction mode A prediction mode is used to decode the current block of video data to generate a decoded block of video data.

In another example, an apparatus includes memory and one or more processors configured to: construct a general most probable mode list comprising N entries, wherein the N entries are intra-frame prediction modes, and wherein the planar mode is the sequential first entry in the general most probable mode list; constructing a main most probable mode list from the first Np entries in the general most probable mode list, where Np is less than N; construct a secondary most probable mode list from the remaining (N-Np) entries in the general most probable mode list; use either the primary most probable mode list or the secondary most probable mode list to decide for the current a current intra-frame prediction mode for a block of video data; and decoding the current block of video data using the current intra-frame prediction mode to generate a decoded block of video data.

In another example, an apparatus includes means for constructing a general most probable mode list comprising N entries, wherein the N entries of the general most probable mode list are intra-frame prediction modes, and wherein the planar mode is Sequential first entry in the general most probable pattern list; used to construct a member of the main most probable pattern list from the first Np entries in the general most probable pattern list, where Np is less than N; used to construct from the general most probable pattern list The remaining (N-Np) entries in the mode list construct the building block of the secondary most probable mode list; used to use the primary most probable mode list or the secondary most probable mode list to determine the current video data block means for intra-frame prediction mode; and means for decoding the current block of video data using the current intra-frame prediction mode to generate a decoded block of video data.

In another example, a non-transitory computer-readable storage medium is encoded with instructions that, when executed, cause a programmable processor to: construct a general most probable pattern list comprising N entries, where the N entries of the general most probable mode list are intra-frame prediction modes, and wherein planar mode is the sequential first entry in the general most probable mode list; from the first Np in the general most probable mode list Entries construct a list of primary most probable modes, where Np is less than N; construct a list of secondary most probable modes from the remaining (N-Np) entries in this general list of most probable modes; use either this list of primary most probable modes or the list of secondary most probable modes A list of possible modes is used to determine a current intra-frame prediction mode for the current block of video data; and the current block of video data is decoded using the current intra-frame prediction mode to generate a decoded block of video data.

In another example, an apparatus includes memory and one or more processors configured to: construct a general most probable mode list comprising N entries, wherein the N entries are intra-frame prediction modes, and wherein the planar mode is the sequential first entry in the general most probable mode list; constructing a main most probable mode list from the first Np entries in the general most probable mode list, where Np is less than N; construct a secondary most probable mode list from the remaining (N-Np) entries in the general most probable mode list; use either the primary most probable mode list or the secondary most probable mode list to decide for the current a current intra-frame prediction mode for a block of video data; and encoding the current block of video data using the current intra-frame prediction mode to generate an encoded block of video data.

The details of one or more examples are set forth in the accompanying drawings and the description below. Other features, objects and advantages will be apparent from the description, drawings and claims.

Generic Video Coding (VVC) was developed by the Joint Video Experts Group (JVET) of ITU-T and ISO/IEC to enable significant compression capabilities beyond HEVC for a wide range of applications. The VVC specification was finalized in July 2020 and published by ITU-T and ISO/IEC. The VVC specification specifies standard bitstream and picture formats, high level syntax (HLS) and coding unit level syntax, and parsing and decoding procedures. VVC also specifies profile/layer/level (PTL) restrictions, byte stream formats, hypothetical reference decoders, and Supplemental Enhancement Information (SEI) in the appendix.

In general terms, this case describes techniques for determining a list of most probable modes for intra-frame prediction and determining an intra-frame prediction mode from the list of most probable modes. The techniques presented in this case can improve the efficiency of generating lists of major and minor most likely patterns. For example, a video encoder and/or a video decoder may be configured to: construct a general most probable mode list containing N entries, where the N entries of the general most probable mode list are intra-frame prediction modes; first Np entries in the list to construct the primary most probable mode list, where Np is less than N; construct the secondary most probable mode list from the remaining (N-Np) entries in the general most probable mode list; and use the primary most probable mode list or a list of second most probable modes to determine the intra-frame prediction mode for the current block of video data.

FIG. 1 is a block diagram illustrating an exemplary video encoding and decoding system 100 that may implement the techniques disclosed herein. In general, the technology of the subject matter involves the decoding (encoding and/or decoding) of video data. Generally, video data includes any data used to process video. Accordingly, video data may include original unencoded video, encoded video, decoded (eg, reconstructed) video, and video metadata (eg, signaling data).

As shown in FIG. 1 , in this example, system 100 includes source device 102 that provides encoded video material to be decoded and displayed by destination device 116 . Specifically, source device 102 provides video material to destination device 116 via computer-readable medium 110 . Source device 102 and destination device 116 may include any of a wide variety of devices, including desktop computers, notebook computers (ie, laptop computers), mobile devices, tablet computers, set-top boxes, such as Phone handsets such as smartphones, televisions, cameras, display devices, digital media players, video game consoles, video streaming devices, broadcast receiver devices, etc. In some cases, source device 102 and destination device 116 may be equipped for wireless communication, and thus may be referred to as wireless communication devices.

In the example of FIG. 1 , source device 102 includes video source 104 , memory 106 , video encoder 200 , and output interface 108 . Destination device 116 includes input interface 122 , video decoder 300 , memory 120 , and display device 118 . In accordance with the teachings, video encoder 200 of source device 102 and video decoder 300 of destination device 116 may be configured to apply techniques for deriving a list of most probable modes for intra-frame prediction. Thus, source device 102 represents an instance of a video encoding device, and destination device 116 represents an instance of a video decoding device. In other instances, the source and destination devices may include other elements or arrangements. For example, source device 102 may receive video material from an external video source, such as an external camera. Likewise, the destination device 116 may interface with an external display device instead of including an integrated display device.

The system 100 shown in FIG. 1 is but one example. In general, any digital video encoding and/or decoding device can perform the techniques for deriving a list of most probable modes for intra-frame prediction. Source device 102 and destination device 116 are merely examples of such decoding devices, where source device 102 generates decoded video data for transmission to destination device 116 . The context of this case refers to a "decoding" device as a device that performs the decoding (eg, encoding and/or decoding) of data. Thus, the video encoder 200 and the video decoder 300 respectively represent an example of a decoding apparatus (specifically, a video encoder and a video decoder). In some examples, source device 102 and destination device 116 may operate in a substantially symmetrical manner, such that source device 102 and destination device 116 each include elements for video encoding and decoding. Thus, system 100 can support one-way or two-way video transmission between source device 102 and destination device 116, eg, for video streaming, video playback, video broadcasting, or video telephony.

Typically, video source 104 represents a source of video data (ie, raw unencoded video data) and provides video encoder 200 with a sequential series of pictures (also referred to as "frames") of the video data , the video encoder 200 encodes the data for the picture. The video source 104 of the source device 102 may include a video capture device, such as a video camera, a video archive unit containing previously captured raw video, and/or a video feed interface for receiving video from a video content provider. As a further alternative, the video source 104 may generate computer graphics-based material as the source video, or a combination of real-time video, archived video, and computer-generated video. In each case, video encoder 200 may encode captured, pre-fetched, or computer-generated video data. Video encoder 200 may rearrange the pictures from the received order (sometimes referred to as the "display order") to the decoding order for decoding. Video encoder 200 may generate a bitstream including encoded video data. The source device 102 may then output the encoded video data to the computer-readable medium 110 via the output interface 108 for reception and/or retrieval by, for example, the input interface 122 of the destination device 116 .

Memory 106 of source device 102 and memory 120 of destination device 116 represent general purpose memory. In some examples, memories 106 , 120 may store raw video data, eg, raw video from video source 104 and raw decoded video data from video decoder 300 . Additionally or alternatively, memories 106, 120 may store software instructions executable by, for example, video encoder 200 and video decoder 300, respectively. Although memory 106 and memory 120 are shown as separate from video encoder 200 and video decoder 300 in this example, it should be understood that video encoder 200 and video decoder 300 may also be included for functionally Internal memory for similar or equivalent purposes. In addition, the memories 106 , 120 may store, for example, encoded video data output from the video encoder 200 and input to the video decoder 300 . In some examples, portions of memory 106, 120 may be allocated as one or more video buffers, eg, to store raw decoded and/or encoded video data.

Computer-readable media 110 may represent any type of media or device capable of transporting encoded video material from source device 102 to destination device 116 . In one example, computer-readable medium 110 represents a communication medium that enables source device 102 to transmit encoded video data directly to destination device 116 in real time, such as via a radio frequency network or a computer-based network. Output interface 108 may modulate transmission signals including encoded video data according to a communication standard such as a wireless communication protocol, and input interface 122 may modulate received transmission signals according to a communication standard such as a wireless communication protocol demodulate. Communication media may include any wireless or wired communication media, eg, the radio frequency (RF) spectrum or one or more physical transmission lines. The communication medium may form part of a packet-based network such as a local area network, a wide area network, or a global network such as the Internet. Communication media may include routers, switches, base stations, or any other device that may be useful for facilitating communication from source device 102 to destination device 116 .

In some examples, source device 102 may output the encoded data from output interface 108 to storage device 112 . Similarly, destination device 116 may access encoded data from storage device 112 via input interface 122 . Storage device 112 may include any of a variety of distributed or locally-accessible data storage media, such as hard disks, Blu-ray discs, DVDs, CD-ROMs, flash memory, volatile or non-volatile memory, or Any other suitable digital storage medium for storing encoded video data.

In some examples, source device 102 may output the encoded video data to file server 114 or to another intermediate storage device that may store the encoded video generated by source device 102 . The destination device 116 may access the stored video data from the file server 114 via streaming or downloading.

File server 114 may be any type of server device capable of storing encoded video data and transmitting the encoded video data to destination device 116 . File server 114 may represent a web server (eg, for a website), a server configured to provide file transfer protocol services, such as file transfer protocol (FTP) or file delivery over one-way transfer (FLUTE) protocol server, Content Delivery Network (CDN) device, Hypertext Transfer Protocol (HTTP) server, Multimedia Broadcast Multicast Service (MBMS) or Enhanced MBMS (eMBMS) server, and/or Network Attached Storage (NAS) device . File server 114 may additionally or alternatively implement one or more HTTP streaming protocols, such as Dynamic Self-Adjusting Streaming over HTTP (DASH), HTTP Live Streaming (HLS), Real Time Streaming Protocol (RTSP), HTTP Dynamic streaming etc.

The destination device 116 may access the encoded video data from the file server 114 via any standard data connection, including an Internet connection. The connections may include wireless channels (eg, Wi-Fi connections), wired connections (eg, digital subscriber line (DSL), cable modems) suitable for accessing encoded video data stored on file server 114 etc.), or a combination of the two. Input interface 122 may be configured to operate in accordance with any one or more of the various protocols discussed above for obtaining or receiving media data from file server 114 or other such protocols for obtaining media data.

Output interface 108 and input interface 122 may represent wireless transmitters/receivers, modems, wired networking elements (eg, Ethernet cards), wireless communication elements operating in accordance with any of the various IEEE 802.11 standards, or other solid components. In examples in which output interface 108 and input interface 122 include wireless components, output interface 108 and input interface 122 may be configured in accordance with cellular communication standards (such as 4G, 4G-LTE (Long Term Evolution), LTE-Advanced, 5G, etc.) to transmit data (such as encoded video data). In some instances where output interface 108 includes a wireless transmitter, output interface 108 and input interface 122 may be configured in accordance with other wireless standards (such as the IEEE 802.11 specification, the IEEE 802.15 specification (eg, ZigBee ^™ ), the Bluetooth ^™ standard, etc.) to transmit data (such as encoded video data). In some examples, source device 102 and/or destination device 116 may include corresponding system-on-chip (SoC) elements. For example, source device 102 may include SoC elements for performing the functions assigned to video encoder 200 and/or output interface 108 , and destination device 116 may include an SoC element for performing the functions assigned to video decoder 300 and/or input interface 122 . functional SoC components.

The techniques described in this case can be applied to video decoding to support any of a variety of multimedia applications, such as over-the-air television broadcasting, cable television transmission, satellite television transmission, Internet streaming video transmission (such as HTTP-based dynamic self-adjusting streaming streaming (DASH)), digital video encoded onto data storage media, decoding of digital video stored on data storage media, or other applications.

The input interface 122 of the destination device 116 receives the encoded video bitstream from the computer-readable medium 110 (eg, communication medium, storage device 112, file server 114, etc.). The encoded video bitstream may include signaling information defined by video encoder 200 that is also used by video decoder 300, such as with information used to describe video blocks or other coding units (eg, slices, pictures, A syntax element for the properties and/or processed values of groups of pictures, sequences, etc. Display device 118 displays the decoded picture of the decoded video material to the user. Display device 118 may represent any of a variety of display devices, such as a liquid crystal display (LCD), plasma display, organic light emitting diode (OLED) display, or another type of display device.

Although not shown in FIG. 1, in some examples, video encoder 200 and video decoder 300 may each be integrated with an audio encoder and/or audio decoder, and may include appropriate MUX-DEMUX units or other hardware software and/or software to process multiplexed streams including both audio and video in the shared data stream. MUX-DEMUX units may conform to the ITU H.223 multiplexer protocol or other protocols such as User Data Packet Protocol (UDP), if applicable.

Video encoder 200 and video decoder 300 may each be implemented as any of a variety of suitable encoder and/or decoder circuitry, such as one or more microprocessors, digital signal processors (DSPs), application-specific Integrated circuit (ASIC), field programmable gate array (FPGA), individual logic, software, hardware, firmware, or any combination thereof. When the techniques are implemented in part in software, the apparatus may store instructions for the software in a suitable non-transitory computer-readable medium and execute the instructions in hardware using one or more processors to execute technology in the case. Each of the video encoder 200 and the video decoder 300 may be included in one or more encoders or decoders, either of which may be integrated as a combined encoder in a corresponding device /decoder (CODEC). Devices including video encoder 200 and/or video decoder 300 may include integrated circuits, microprocessors, and/or wireless communication devices such as cellular telephones.

Video encoder 200 and video decoder 300 may be based on video coding standards such as ITU-T H.265 (also known as the High Efficiency Video Coding (HEVC) standard) or extensions thereto such as multi-view and/or Scalable Video Codec Extension)) to operate. Alternatively, video encoder 200 and video decoder 300 may operate according to other proprietary or industry standards, such as ITU-T H.266, also known as Generic Video Coding (VVC). A draft of the VVC standard is described in: Bross et al., "Versatile Video Coding (Draft 10)", Joint Video Experts Group of ITU-T SG 16 WP 3 and ISO/IEC JTC 1/SC 29/WG 11 (JVET), 18th meeting: via conference call, June 22-July 1, 2020, JVET-S2001-vA (hereinafter referred to as "VVC Draft 10"). However, the techniques of the present case are not limited to any particular decoding standard.

In general, video encoder 200 and video decoder 300 may perform block-based coding of pictures. The term "block" generally refers to a structure that includes data to be processed (eg, to be encoded, decoded, or otherwise used in an encoding and/or decoding process). For example, a block may include a two-dimensional matrix of samples of luma and/or chroma data. Generally, the video encoder 200 and the video decoder 300 can decode video data represented in YUV (eg, Y, Cb, Cr) format. That is, instead of decoding red, green, and blue (RGB) data for sampling of a picture, video encoder 200 and video decoder 300 may decode luma and chroma components, where the chroma components Both red hue and blue hue chrominance components may be included. In some examples, video encoder 200 converts the received RGB-formatted data to a YUV representation before encoding, and video decoder 300 converts the YUV representation to RGB format. Alternatively, a preprocessing unit and a postprocessing unit (not shown) may perform these conversions.

In general terms, the subject matter may relate to the coding (eg, encoding and decoding) of a picture to include a procedure for encoding or decoding the material of the picture. Similarly, the subject matter may relate to the coding of blocks of pictures to include procedures for encoding or decoding (eg, prediction and/or residual coding) data for the blocks. The encoded video bitstream typically includes a series of values for syntax elements that represent coding decisions (eg, coding modes) and partition the picture into blocks. Accordingly, references to coding a picture or block should generally be understood as coding the values of syntax elements used to form the picture or block.

HEVC defines various blocks, including coding units (CUs), prediction units (PUs), and transform units (TUs). According to HEVC, a video coder, such as video encoder 200, partitions coding tree units (CTUs) into CUs according to a quad-tree structure. That is, the video coder partitions CTUs and CUs into four equal, non-overlapping squares, and each node of the quadtree has zero or four child nodes. A node without child nodes may be referred to as a "leaf node," and a CU of such a leaf node may include one or more PUs and/or one or more TUs. The video coder may further partition PUs and TUs. For example, in HEVC, a residual quadtree (RQT) represents the partitioning of TUs. In HEVC, PU stands for inter-frame prediction data, and TU stands for residual data. An intra-frame predicted CU includes intra-frame prediction information, such as an intra-frame mode indication.

As another example, video encoder 200 and video decoder 300 may be configured to operate according to VVC. According to VVC, a video coder, such as video encoder 200, partitions a picture into a plurality of coding tree units (CTUs). The video encoder 200 may partition the CTUs according to a tree structure, such as a quad-tree-binary tree (QTBT) structure or a multi-type tree (MTT) structure. The QTBT structure removes the concept of various partition types, such as the partition between CUs, PUs and TUs of HEVC. The QTBT structure includes two levels: a first level that is partitioned according to quadtree partitioning, and a second level that is partitioned according to binary tree partitioning. The root node of the QTBT structure corresponds to the CTU. The leaf nodes of the binary tree correspond to coding units (CUs).

In an MTT partition structure, blocks may be partitioned using quadtree (QT) partitions, binary tree (BT) partitions, and one or more types of ternary tree (TT) (also known as triple tree (TT)) partitions to split. A ternary tree or ternary tree partition is a partition in which a block is split into three sub-blocks. In some examples, ternary or ternary tree partitioning divides the block into three sub-blocks without dividing the original block via the center. Segmentation types (eg, QT, BT, and TT) in MTT can be symmetric or asymmetric.

In some examples, video encoder 200 and video decoder 300 may use a single QTBT or MTT structure to represent each of the luma and chroma components, while in other examples, video encoder 200 and video decoder 300 Two or more QTBT or MTT structures may be used, such as one QTBT/MTT structure for the luma component and another QTBT/MTT structure for the two chroma components (or two for the corresponding chroma components). QTBT/MTT structure).

Video encoder 200 and video decoder 300 may be configured to use per-HEVC quadtree partitioning, QTBT partitioning, MTT partitioning, or other partitioning structures. For explanatory purposes, a description of the techniques of the present case is provided with respect to QTBT segmentation. It should be understood, however, that the techniques of this disclosure may also be applied to video decoders configured to use quad-tree partitioning, or other types of partitioning as well.

In some examples, a CTU includes a coding tree block (CTB) of luma samples with three sample arrays, two corresponding CTBs of chroma samples, or a monochrome picture or coded using three separate color planes The CTB of the samples of the coded picture, and the syntax structure used to code the samples. A CTB may be an NxN block of samples for some value of N, such that dividing the components into CTBs is a division. A component can be an array from three arrays (luminance and two chrominance) including pictures in 4:2:0, 4:2:2 or 4:4:4 color format or a single from one of the three arrays A sample, or an array including a picture in monochrome format or a single sample of the array. In some examples, a coding block is an MxN block of samples for some values of M and N, such that dividing the CTB into coding blocks is a partition.

Blocks (eg, CTUs or CUs) may be classified in a picture in various ways. As an example, a brick may represent a rectangular area of a CTU row within a particular tile in the picture. A tile can be a rectangular area of a CTU within a specific tile column and a specific tile row in the picture. A tile column represents a rectangular area of a CTU that has a height equal to the height of the picture and a width specified by a syntax element (eg, such as in a picture parameter set). A tile row represents a rectangular area of a CTU that has a height specified by a syntax element (eg, such as in a picture parameter set) and a width equal to the width of the picture.

In some instances, a tile may be partitioned into multiple tiles, each of which may include one or more CTU rows within the tile. Tiles that are not divided into bricks can also be called bricks. However, bricks that are a true subset of tiles may not be called tiles.

The bricks in the picture can also be arranged in slices. A slice can be an integer number of bricks of a picture, which can be uniquely contained in a single Network Abstraction Layer (NAL) unit. In some instances, a slice includes several complete tiles or a contiguous sequence of complete bricks that includes only one tile.

The content of this case may use "NxN" and "N by N" interchangeably to refer to the sampling dimensions of a block (such as a CU or other video block) in vertical and horizontal dimensions, eg, 16x16 samples or 16 by 16 samples . Typically, a 16x16 CU will have 16 samples in the vertical direction (y=16) and 16 samples in the horizontal direction (x=16). Likewise, an NxN CU typically has N samples in the vertical direction and N samples in the horizontal direction, where N represents a non-negative integer value. The samples in the CU can be arranged in rows and columns. Furthermore, a CU does not necessarily need to have the same number of samples in the horizontal direction as in the vertical direction. For example, a CU may include NxM samples, where M is not necessarily equal to N.

Video encoder 200 encodes video data representing prediction and/or residual information and other information for a CU. The prediction information indicates how the CU is to be predicted in order to form a prediction block for the CU. Residual information typically represents the sample-by-sample difference between the samples of the CU prior to encoding and the prediction block.

To predict a CU, video encoder 200 may typically form prediction blocks for the CU via inter-frame prediction or intra-frame prediction. Inter-frame prediction generally refers to predicting a CU from data from previously coded pictures, while intra-frame prediction generally refers to predicting a CU from previously coded data of the same picture. To perform inter-frame prediction, video encoder 200 may use one or more motion vectors to generate prediction blocks. Video encoder 200 may typically perform a motion search to identify reference blocks that closely match the CU, for example, in the difference aspect between the CU and the reference block. Video encoder 200 may use the following to calculate difference metrics to decide whether a reference block closely matches the current CU: Sum of Absolute Differences (SAD), Sum of Squared Differences (SSD), Mean Absolute Difference (MAD), Average variance (MSD), or other such difference calculations. In some examples, video encoder 200 may predict the current CU using uni-directional prediction or bi-directional prediction.

Some examples of VVC also provide an affine motion compensation mode, which can be thought of as an inter-frame prediction mode. In the affine motion compensation mode, video encoder 200 may decide two or more motion vectors for representing non-translational motion, such as zoom-in or zoom-out, rotation, perspective motion, or other irregular motion types.

To perform intra-frame prediction, video encoder 200 may select an intra-frame prediction mode to generate prediction blocks. Some examples of VVC provide sixty-seven intra-frame prediction modes, including various directional modes, as well as planar and DC modes. Typically, video encoder 200 selects an intra-frame prediction mode that describes the adjacent samples of the current block from which samples of the current block (eg, a block of a CU) are to be predicted. Assuming that video encoder 200 decodes CTUs and CUs in raster scan order (left-to-right, top-to-bottom), such sampling may typically be in the current block in the same picture as the current block top, top left, or left.

Video encoder 200 encodes data representing the prediction mode for the current block. For example, for an inter-frame prediction mode, video encoder 200 may encode data indicating which of the various available inter-frame prediction modes to use, as well as motion information for the corresponding mode. For uni-directional or bi-directional inter-frame prediction, for example, video encoder 200 may use Advanced Motion Vector Prediction (AMVP) or merge mode to encode motion vectors. Video encoder 200 may use a similar mode to encode motion vectors for affine motion compensation modes.

After prediction, such as intra-frame prediction or inter-frame prediction for a block, video encoder 200 may compute residual data for the block. Residual data, such as residual blocks, represent sample-by-sample differences between the block and the prediction block for that block, which was formed using the corresponding prediction mode. Video encoder 200 may apply one or more transforms to the residual block to produce transformed data in the transform domain rather than in the sample domain. For example, video encoder 200 may apply a discrete cosine transform (DCT), integer transform, wavelet transform, or conceptually similar transform to the residual video data. Additionally, the video encoder 200 may apply a secondary transform, such as Mode Dependent Non-Separable Secondary Transform (MDNSST), Signal Dependent Transform, Karhunen-Loeve Transform (KLT), etc., after the first transform. Video encoder 200 generates transform coefficients after applying one or more transforms.

As previously described, after any transform to generate transform coefficients, video encoder 200 may perform quantization of the transform coefficients. Quantization generally represents a procedure in which transform coefficients are quantized to possibly reduce the amount of data used to represent the transform coefficients, thereby providing further compression. By performing a quantization process, video encoder 200 may reduce the bit depth associated with some or all transform coefficients. For example, video encoder 200 may round down an n- bit value to an m -bit value during quantization, where n is greater than m . In some examples, to perform quantization, video encoder 200 may perform a bitwise right shift of the value to be quantized.

After quantization, video encoder 200 may scan the transform coefficients to generate a one-dimensional vector from a two-dimensional matrix including the quantized transform coefficients. A scan can be designed to place higher energy (and therefore lower frequency) transform coefficients at the front of the vector, and lower energy (and therefore higher frequency) transform coefficients at the back of the vector. In some examples, video encoder 200 may scan the quantized transform coefficients using a predefined scan order to generate a serialized vector, and then entropy encode the quantized transform coefficients of the vector. In other examples, video encoder 200 may perform a self-adjusting scan. After scanning the quantized transform coefficients to form a one-dimensional vector, video encoder 200 may entropy encode the one-dimensional vector, eg, according to context self-adjusting binary arithmetic coding (CABAC). Video encoder 200 may also entropy encode the values of syntax elements used to describe metadata associated with the encoded video data for use by video decoder 300 in decoding the video data.

To perform CABAC, video encoder 200 may assign contexts within a context model to symbols to be transmitted. The context may relate to, for example, whether adjacent values of a symbol are zero-valued. Probabilistic decisions may be based on the context assigned to the symbol.

Video encoder 200 may also generate syntax data such as block-based syntax data, picture-based syntax data, and sequence-based syntax data to video decoder 300, eg, in picture headers, block headers, slice headers ), or other syntactic data (such as Sequence Parameter Set (SPS), Picture Parameter Set (PPS), or Video Parameter Set (VPS)). Likewise, the video decoder 300 can decode the syntax data to determine how to decode the corresponding video data.

In this manner, video encoder 200 may generate a bitstream that includes encoded video data, eg, for describing partitioning of pictures into blocks (eg, CUs) and predictions and/or predictions for those blocks. or syntax element for residual information. Finally, the video decoder 300 can receive the bitstream and decode the encoded video data.

Typically, video decoder 300 performs the reverse of the process performed by video encoder 200 to decode the encoded video data of the bitstream. For example, video decoder 300 may use CABAC to decode the values of syntax elements for a bitstream in a substantially similar but reversed manner as the CABAC encoding procedure of video encoder 200. The syntax elements may define partitioning information for partitioning a picture into CTUs, and partitioning each CTU according to a corresponding partitioning structure, such as a QTBT structure, to define the CUs of the CTU. Syntax elements may also define prediction and residual information for blocks of video data (eg, CUs).

Residual information may be represented by, for example, quantized transform coefficients. Video decoder 300 may inverse quantize and inverse transform the quantized transform coefficients of a block to reproduce a residual block for the block. Video decoder 300 uses the signaled prediction mode (intra-frame prediction or inter-frame prediction) and associated prediction information (eg, motion information for inter-frame prediction) to form a prediction region for the block piece. Video decoder 300 may then combine the prediction block and the residual block (on a sample-by-sample basis) to reproduce the original block. Video decoder 300 may perform additional processing, such as performing deblocking procedures to reduce visual artifacts along the boundaries of blocks.

In general, the content of this case may involve the "signaling" of certain information (such as grammatical elements). The term "signaling" may generally refer to the transmission of values for syntax elements and/or other data for decoding encoded video data. That is, video encoder 200 may signal values for syntax elements in the bitstream. Typically, the signalling represents the value generated in the bitstream. As previously mentioned, source device 102 may stream the bitstream to destination device 116 substantially instantaneously or not (such as may occur when syntax elements are stored to storage device 112 for later retrieval by destination device 116) .

In accordance with the techniques of the present disclosure, as will be explained in greater detail below, video encoder 200 and video decoder 300 may be configured to: construct a general most probable pattern list containing N entries, where the N entries of the general most probable pattern list is the intra-frame prediction mode, and where the planar mode is the sequential first entry in the general most probable mode list; constructs the primary most probable mode list from the first Np entries in the general most probable mode list, where Np is less than N; from The remaining (N-Np) entries in the general most probable mode list construct the secondary most probable mode list; use the primary most probable mode list or the secondary most probable mode list to determine the current frame for the current video data block a prediction mode; and decoding the current block of video data using the current intra-frame prediction mode.

Exemplary intra-frame coding modes include DC mode, planar mode, and directional modes (eg, non-planar mode). In VVC, J. Chen, Y. Ye and S.-H. Kim, "Algorithm description for Versatile Video Coding and Test Model 9 (VTM 9)", JVET-R2002, April 2020, 65 directional modes for For in-frame prediction of blocks. To decode the intra-frame mode values, the video encoder 200 and the video decoder 300 may be configured to derive a most probable mode (MPM) list. If the intra-frame mode used to code a particular CU is a mode in the MPM list, video encoder 200 may only signal the index of the determined intra-frame mode in the MPM list. Otherwise, video encoder 200 may use bypass coding (eg, entropy coding with a fixed probability model) to signal the mode value.

In VVC, there are six entries in the MPM list. The first entry in the MPM list is the flat mode. The remaining entries in the MPM list are derived from the intra-frame mode of the left (L) adjacent block and the upper (A) adjacent block of the CU 400 (see Figure 2), from the directional intra-frame mode of the adjacent blocks It consists of the output in-frame mode and the default in-frame mode. For the remainder of the discussion in the content of this case, this MPM list will be referred to as the primary MPM list .

Two MPM lists are proposed in: A. Ramasubramonian et al., "CE3-3.1.1: Two MPM modes and shape dependency (Test 3.1.1)," ITU-T SG 16 WP 3 and ISO/IEC Joint Video Exploration Team (JVET) of JTC 1/SC 29/WG 11, 11th meeting: Lubujana, Slovenia, 10-18 July 2018 (hereinafter referred to as "JVET-K0081" ). One MPM list is a primary MPM (PMPM) list with 6 entries, and the other MPM list is a secondary MPM (SMPM) list with 16 entries. Entries in the PMPM list are derived using the in-frame mode of the left (L), top (A), bottom left (BL), top right (AR), and top left (AL) adjacent blocks of the CU 402, As shown in Figure 3. The SMPM list is generated from patterns near (eg, close in angle or index value) of the directional patterns included in the PMPM list.

For example, if the first entry in the PMPM list is in-frame mode 12, and the maximum offset is 4, then in-frame modes 11, 10, 9, 8, 13, 14, 15, and 16 are added to the SMPM list, respectively , provided that this in-frame mode is not already included in the two MPM lists. That is, all patterns that add or subtract 4 indices from the in-frame pattern index 12 are added to the list, as long as such patterns are not duplicates of patterns already in the list.

The maximum offset used for the 6 main MPMs in JVET-K0081 is {4, 3, 3, 2, 2, 1}. If the program does not populate the 16 entries in the SMPM list, the remaining entries are filled from the default list of in-frame modes. The video encoder may signal a syntax element indicating whether the intra-frame prediction mode for the block is from the PMPM list or the SMPM list.

The content of this case describes different techniques for improving the construction of MPM lists consisting of PMPM lists and SMPM lists. In particular, the present disclosure describes techniques for constructing a general list of most probable patterns and then constructing lists of primary and secondary most probable patterns from the general list of most probable patterns. The primary and secondary most probable mode lists may include intra-prediction modes from neighboring blocks and intra-prediction mode offsets for the intra-prediction modes of neighboring blocks.

General MPM list construction

First, a general MPM (GMPM) list can be defined with N entries, where the ith entry of the GMPM list is denoted as GMPM[i]. The first entry of the GMPM list is the flat mode. That is, index 0 of the GMPM list (eg, GMPM[0]) indicates the plane intra-frame mode. For example, as shown in FIG. 3, the intra-frame mode of the adjacent blocks to the left (L), upper (A), lower left (BL), upper right (AR) and upper left (AL) of the current decoding block can be denoted as MPM(L), MPM(A), MPM(BL), MPM(AR), and MPM(AL), respectively.

If MPM(j) is available and has not been included in the GMPM list, the video encoder 200 and the video decoder 300 are configured to use the intra-frame modes MPM(L), MPM(A), MPM(BL), MPM( AR) and MPM (AL) are added to the GMPM list to construct the GMPM list. If neighboring block j has an associated intra-frame prediction mode, then the intra-frame mode MPM(j) is available. For example, if adjacent blocks are coded using intra-frame prediction, the adjacent blocks may have associated intra-frame prediction modes. In other examples, neighboring blocks may have an associated intra-frame prediction mode even though intra-frame prediction is not used for coding.

Video encoder 200 and video decoder 300 may offset the first Na available directions between MPM(L), MPM(A), MPM(BL), MPM(AR), and MPM(AL) intra-frame prediction modes In-frame mode to derive the remaining entries in the GMPM list, where Na is less than the left (L), upper (A), lower left (BL), upper right (AR), and upper left (AL) adjacent blocks the numerical value of the quantity. For example, Na can be less than 5.

In-frame modes other than MPM(L), MPM(A), MPM(BL), MPM(AR) and MPM(AL) included in the GMPM list are denoted as GMPM[p]=MPM(j), where 1≦P≦Nb, Nb is less than or equal to 5, and j is one of L, A, BL, AR, and AL. If p is less than the predefined value q, the maximum offset is set to M1; otherwise, the maximum offset is set to M2. If the proposed procedure does not fill N entries in the GMPM list, the remaining entries are filled from the preset list. The first Np entries in the GMPM list are set as the PMPM list, and the remaining (N–Np) entries in the GMPM list are set as the SMPM list.

As an example, if the first entry in the PMPM list is in-frame mode 12, and the maximum offset is 4, then in-frame modes 11, 10, 9, 8, 13, 14, 15, and 16 are each added to SMPM list, provided that this in-frame mode is not already included in both MPM lists. That is, all patterns that add or subtract 4 indices from the in-frame pattern index 12 are added to the list, as long as such patterns are not duplicates of patterns already in the list. In another example, if the first entry of the PMPM list is in-frame mode 12, and the maximum offset is 3, then in-frame modes 11, 10, 9, 13, 14, and 15 are each added to the SMPM list , provided that this in-frame mode is not already included in the two MPM lists. That is, all patterns that add or subtract 3 indices from the in-frame pattern index 12 are added to the list, provided that such patterns are not duplicates of patterns already in the list.

In one example, N=22, Np=6, Na=2, q=3, M1=4 and M2=3. In this example, the size of the GMPM list is 22 entries, with the first 6 entries being the PMPM list and the last 16 entries being the SMPM list. The first two available directional in-frame modes in MPM(L), MPM(A), MPM(BL), MPM(AR) and MPM(AL) are shifted to derive around the two available directional in-frame modes The orientation of the in-frame mode. Nearby in this context means adding or subtracting M1 or M2 indices from the indices of the available directional intra-frame modes. If GMPM[1] and GMPM[2] are in non-DC mode, the maximum offset is 4 for GMPM[1] and GMPM[2]. If GMPM[1] is in DC mode, and GMPM[2] and GMPM[3] are in non-DC mode, then the maximum offset is 4 for GMPM[2] and 3 for GMPM[3]. If GMPM[2] is in DC mode, and GMPM[1] and GMPM[3] are in non-DC mode, then the maximum offset is 4 for GMPM[1] and 3 for GMPM[3]. For example, if GMPM[1]=20 and GMPM[3]=40, then patterns 16, 17, 18, 19, 21, 22, 23, and 24 offset from GMPM[1] and offset from GMPM[3] The modes 37, 38, 39, 41, 42 and 43 will be added to the GMPM list.

MPM index decoding

In one example for VVC, the video decoder 300 may be configured to decode and parse the plane flag first to decide whether the intra-frame mode for the CU is the first entry of the PMPM list. If the plane flag does not indicate a plane mode, the video decoder 300 may be configured to decode and parse the index value (eg, a syntax element for indicating the index value) to determine which entry of the PMPM list is selected. Note that parsed index values 0, 1, 2, 3, and 4 correspond to entries 1, 2, 3, 4, and 5 of the PMPM list, respectively, and parsed for index values 0, 1, The bins of 2, 3, and 4 are 0, 10, 110, 1110, and 1111, respectively.

New decoding tools called In-Frame Sub-Partition (ISP) mode and Multiple Auxiliary Line (MRL) mode have been integrated into VVC. ISP mode and normal in-frame mode share the same PMPM list. The MRL mode applies to the in-frame modes in the PMPM list, except for the first entry (ie, the planar mode). Since the general in-frame mode, ISP mode and MRL mode all share the same non-planar PMPM entry, that is, the 1st, 2nd, 3rd, 4th, and 5th entries of the PMPM list, it is necessary to use the normal in-frame Mode-conditioned context decoding of mode, ISP mode, and MRL mode will improve the decoding efficiency when signaling the PMPM index. Thus, in accordance with the techniques of this disclosure, video encoder 200 and video decoder 300 may be configured to decode the first bin of a non-planar PMPM index using three context models as follows: If (ISP mode): Code the first bin of the non-planar PMPM index with context index 0. Otherwise, if (MRL mode): Code the first bin of the non-planar PMPM index with context index 1. Otherwise (normal intra-frame mode): use context index 2 to code the first bin of the non-planar PMPM index.

When using the techniques of this case, the order of the if-else can be changed to other combinations. An example is as follows: If (MRL mode): The first bin of the non-planar PMPM index is coded with context index 0. Else, if (ISP mode): Code the first bin of the non-planar PMPM index with context index 1. Otherwise (normal intra-frame mode): use context index 2 to code the first bin of the non-planar PMPM index.

example

As before, two MPM lists may be used: one is a primary MPM (PMPM) list with 6 entries, and the other is a secondary MPM (SMPM) list with 16 entries. According to the techniques of the present disclosure, the video encoder 200 and the video decoder 300 can construct a general MPM list with 22 entries, wherein the first 6 entries in the general MPM list are included in the PMPM list, and the 22 entries are included in the PMPM list. The remaining entries are set as SMPM lists. The first entry in the general MPM list (eg, sequential first entry) is the flat mode. The rest of the entries consist of in-frame modes of the left (L), upper (A), lower left (BL), upper right (AR) and upper left (AL) adjacent blocks (as shown in Figure 3), from adjacent The first two available direction modes of the block are composed of the direction mode offset and the default mode. If the CU block is rectangular and oriented vertically, that is, when the height is greater than the width, the order of adjacent blocks checked for available intra-frame prediction modes is A, L, BL, AR, AL. Otherwise, the order is L, A, BL, AR, AL.

The maximum offset of the directional pattern of adjacent blocks depends on the entry point of the directional pattern in the general MPM list. If the available direction mode of the adjacent block is in the second or third entry (note that the first entry is the plane mode), the maximum offset is set to 4; otherwise, the maximum offset is set to 3. For example, the ith entry of a general MPM list is denoted as GMPM[i]. GMPM[0]=Planar Mode. If GMPM[1] is in DC mode, and GMPM[2] and GMPM[3] are in directional mode, the maximum offset is 4 for GMPM[2] and 3 for GMPM[3]. Suppose GMPM[2]=20 and GMPM[3]=40. then 16, 17, 18, 19, 21, 22, 23, and 24 offset from GMPM[2] and 37, 38, 39, 41, 42, and 43 offset from GMPM[3] are added to the GMPM list .

Video decoder 300 may first decode and parse the plane flag to determine whether the intra-frame mode for the CU is the first entry in the PMPM list. If the plane flag does not indicate that the plane mode is to be used, the video decoder 300 decodes and parses the index value for the non-plane mode of the PMPM list to determine which entry of the PMPM list to select. Note that the parsed index values 0, 1, 2, 3, 4 for non-planar mode correspond to the 1st, 2nd, 3rd, 4th, 5th entries of the PMPM list, and for index values 0, 1, The parsed bins for 2, 3, and 4 are 0, 10, 110, 1110, 1111, respectively. Video encoder 200 and video decoder 300 may be configured to use 3 context models to code the first bin for the non-planar mode index in the PMPM list as follows: If(ISP): The first bin is decoded with context index 0. Otherwise, if(MRL): decode the first bin with context index 1. Otherwise (in normal frame): decode the first bin with context index 2.

In summary, in one example of the present disclosure, video decoder 300 may be configured to decode a current block of video data using intra-frame prediction. Video decoder 300 may be configured to construct a general most probable mode list containing N entries, where the N entries of the general most probable mode list are intra-frame prediction modes, and where the planar mode is the order in the general most probable mode list first entry. The video decoder 300 may also construct the primary most probable mode list from the first Np entries in the general most probable mode list, where Np is less than N, and construct the secondary most probable mode list from the remaining (N-Np) entries in the general most probable mode list List of most likely patterns. Then, the video decoder 300 can use the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data, and use the current intra-frame prediction mode for the current video data The blocks are decoded to produce decoded blocks of video data. In one example, N is 22 and Np is 6.

In one example, in order to determine the current intra-frame prediction mode, the video decoder 300 may also be configured to decode an index of the primary most probable mode list or the secondary most probable mode list, where the index indicates the primary most probable mode list or The non-planar intra-frame prediction mode in the second most probable mode list. The video decoder 300 may determine the current intra-frame prediction mode for the current block of video data based on the index.

In another example, in order to decode the index of the primary most probable mode list or the secondary most probable mode list, the video decoder 300 may also determine the first index to be used for the index based on the coding tool used for the current block. A context for entropy decoding of one bin, and the context is used to entropy decode the first bin of the index. In one example, the coding tool is one of a general intra-frame prediction mode, an intra-frame subpartition mode, or a multiple auxiliary line mode.

In another example of the subject matter, in order to construct the general most probable mode list, the video decoder 300 may be configured to: add the corresponding intra-frame prediction modes from the corresponding neighboring blocks of the current video data block to the and adding to the general most probable mode list a plurality of intra-frame prediction modes offset from corresponding intra-frame prediction modes from corresponding neighboring blocks. In one example, video decoder 300 may convert corresponding frames from corresponding neighboring blocks of the current block of video data based on the fact that the corresponding intra-frame prediction mode is available and has not been added to the general most probable mode list Intra-prediction modes are added to the list of general most probable modes.

In another example, in order to determine the current intra-frame prediction mode for the current block of video data using the primary most probable mode list or the secondary most probable mode list, the video decoder 300 may be configured to: Decode the syntax elements of the current MPM list from either the primary MPM list or the secondary MPM list; decode the index into the current MPM list; and determine the current message based on the index to the current MPM list. In-box prediction mode.

Reciprocally, the video encoder 200 is also configured to encode the current block of video data using intra-frame prediction. The video encoder 200 may be configured to construct a general most probable mode list containing N entries, wherein the N entries of the general most probable mode list are intra-frame prediction modes, and wherein the planar mode is in the general most probable mode list Order first entry. The video encoder 200 may also construct the primary most probable mode list from the first Np entries in the general most probable mode list, where Np is less than N, and construct the secondary most probable mode list from the remaining (N-Np) entries in the general most probable mode list List of most likely patterns. The video encoder 200 may also use the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data, and use the current intra-frame prediction mode for the current video data area. The blocks are encoded to produce encoded blocks of video data. In one example, N is 22 and Np is 6.

In one example of the subject matter, the video encoder 200 may be configured to encode an index of the primary most probable mode list or the secondary most probable mode list, wherein the index indicates the primary most probable mode list or the secondary most probable mode list The non-planar intra-frame prediction mode in .

In another example of the content of the present case, in order to encode the index of the primary most probable mode list or the secondary most probable mode list, the video encoder 200 may be configured to: for entropy encoding the first bin of the index; and using the context to entropy encode the first bin of the index. In one example, the coding tool is one of a general intra-frame prediction mode, an intra-frame subpartition mode, or a multiple auxiliary line mode.

In another example, in order to construct the general most probable mode list, the video encoder 200 may also be configured to add corresponding intra-frame prediction modes from corresponding neighboring blocks of the current video data block to the general most probable mode list. and adding a plurality of intra-frame prediction modes offset from corresponding intra-frame prediction modes from corresponding neighboring blocks to the general most probable mode list. The video encoder 200 may add a corresponding intra-frame prediction mode from a corresponding neighboring block of the current video data block based on the corresponding intra-frame prediction mode is available and has not been added to the general most probable mode list to the general list of most probable patterns.

4A and 4B are conceptual diagrams illustrating an example quadtree binary tree (QTBT) structure 130 and corresponding coding tree unit (CTU) 132 . Solid lines indicate quad-tree separation, and dashed lines indicate binary-tree separation. In each split (ie, non-leaf) node of the binary tree, a flag is signaled to indicate which split type is used (ie, horizontal or vertical), where in this example 0 indicates horizontal split and 1 indicates vertical separation. For quadtree split, since the quadtree node splits the block horizontally and vertically into 4 subblocks of equal size, there is no need to indicate the split type. Accordingly, video encoder 200 can encode, and video decoder 300 can decode, syntax elements (such as separation information) for region tree level (ie, solid lines) of QTBT structure 130 ), and syntax elements (such as separation information) for the prediction tree level (ie, dashed line) of the QTBT structure 130 . Video encoder 200 may encode video data, such as prediction and transform data, for the CU represented by the terminal leaf node of QTBT structure 130, and video decoder 300 may decode the video data.

In general, the CTU 132 of FIG. 4B may be associated with parameters that define the size of the blocks corresponding to nodes of the QTBT structure 130 at the first and second levels. Such parameters may include CTU size (representing the size of the CTU 132 in the sample), minimum quadtree size (MinQTSize, which represents the minimum allowed quad-leaf node size), maximum binary tree size (MaxBTSize, which represents the maximum allowed binary tree root node size) size), the maximum binary tree depth (MaxBTDepth, which represents the maximum allowed binary tree depth), and the minimum binary tree size (MinBTSize, which represents the minimum allowed binary leaf node size).

The root node of the QTBT structure corresponding to the CTU may have four child nodes at the first level of the QTBT structure, and each child node may be partitioned according to quadtree partitioning. That is, the nodes of the first level are leaf nodes (no children) or have four children. An instance of the QTBT structure 130 represents such a node as including a parent node and child nodes with solid-line branches. If the nodes of the first level are not larger than the maximum allowable binary tree root node size (MaxBTSize), the nodes can be further divided via the corresponding binary tree. The binary tree separation of a node can be iterated until the node resulting from the separation reaches the minimum allowable binary leaf node size (MinBTSize) or the maximum allowable binary tree depth (MaxBTDepth). An example of the QTBT structure 130 represents such a node as having dashed lines for branches. A binary leaf node, called a coding unit (CU), is used for prediction (eg, intra- or inter-picture prediction) and transform without any further partitioning. As discussed above, CUs may also be referred to as "video blocks" or "blocks."

In one example of a QTBT partition structure, the CTU size is set to 128x128 (a luma sample and two corresponding 64x64 chroma samples), MinQTSize is set to 16x16, MaxBTSize is set to 64x64, MinBTSize (for both width and height) is set to 4, and MaxBTDepth is set to 4. Quadtree partitioning is first applied to the CTU to generate quad-leaf nodes. A quad-leaf node can have a size from 16x16 (ie MinQTSize) to 128x128 (ie CTU size). If the leaf quadtree node is 128x128, then since the size exceeds MaxBTSize (ie, 64x64 in this example), the leaf quadtree node will not be further separated by the binary tree. Otherwise, the leaf quadtree node will be further split by the binary tree. Therefore, the quad-leaf node is also the root node for the binary tree and has a binary tree depth of 0. When the binary tree depth reaches MaxBTDepth (4 in this instance), no further separation is allowed. A binary tree node with a width equal to MinBTSize (4 in this example) means that no further vertical separation (ie, division of width) is allowed for that binary tree node. Similarly, a binary tree node with a height equal to MinBTSize means that no further horizontal separation (ie, division of heights) is allowed for that binary tree node. As mentioned earlier, the leaf nodes of the binary tree are called CUs and are further processed according to prediction and transformation without further partitioning.

5 is a block diagram illustrating an exemplary video encoder 200 that may perform the techniques disclosed herein. FIG. 5 is provided for purposes of explanation and should not be considered limiting of the techniques broadly illustrated and described in the context of this case. For explanatory purposes, the content of this case describes a video encoder 200 according to the techniques of VVC (ITU-T H.266 under development) and HEVC (ITU-T H.265). However, the techniques of the present disclosure may be performed by video encoding devices configured to other video coding standards.

In the example of FIG. 5, the video encoder 200 includes a video data memory 230, a mode selection unit 202, a residual generation unit 204, a transform processing unit 206, a quantization unit 208, an inverse quantization unit 210, an inverse transform processing unit 212, a Configuration unit 214 , filter unit 216 , decoded picture buffer (DPB) 218 , and entropy encoding unit 220 . Video data memory 230, mode selection unit 202, residual generation unit 204, transform processing unit 206, quantization unit 208, inverse quantization unit 210, inverse transform processing unit 212, reconstruction unit 214, filter unit 216, DPB 218 and Any or all of entropy encoding units 220 may be implemented in one or more processors or in processing circuitry. For example, the elements of video encoder 200 may be implemented as one or more circuits or logic elements, as part of a hardware circuit system, or as part of a processor, ASIC or FPGA. Furthermore, video encoder 200 may include additional or alternative processors or processing circuitry to perform these and other functions.

The video data memory 230 may store video data to be encoded by the components of the video encoder 200 . Video encoder 200 may receive video data stored in video data memory 230 from, for example, video source 104 (FIG. 1). DPB 218 may act as a reference picture memory that stores reference video data for use in prediction of subsequent video data by video encoder 200 . Video data memory 230 and DPB 218 may be formed from any of a variety of memory devices, such as dynamic random access memory (DRAM) (including synchronous DRAM (SDRAM)), magnetoresistive RAM (MRAM), resistive RAM ( RRAM), or other types of memory devices. Video data memory 230 and DPB 218 may be provided by the same memory device or by separate memory devices. In various examples, video data memory 230 may be on-chip with other components of video encoder 200 (as shown), or off-chip relative to those components.

In the context of this case, references to video data memory 230 should not be construed as limited to memory internal to video encoder 200 (unless so specifically described), or to memory external to video encoder 200 (unless so specifically described). Rather, references to video data memory 230 should be understood as reference memory that stores video data received by video encoder 200 for encoding (eg, video data for the current block to be encoded). The memory 106 of FIG. 1 may also provide temporary storage of outputs from the various units of the video encoder 200 .

The various elements of FIG. 5 are illustrated to aid in understanding the operations performed by the video encoder 200 . The units may be implemented as fixed function circuits, programmable circuits, or a combination thereof. Fixed-function circuits represent circuits that provide specific functions and are preset with respect to operations that can be performed. Programmable circuits represent circuits that can be programmed to perform various tasks and provide flexible functionality in operations that can be performed. For example, the programmable circuit may execute software or firmware that causes the programmable circuit to operate in a manner defined by the instructions of the software or firmware. Fixed-function circuits can execute software instructions (eg, to receive parameters or output parameters), but the types of operations performed by fixed-function circuits are generally immutable. In some examples, one or more of the cells may be different circuit blocks (fixed function or programmable), and in some examples, one or more of the cells may be integrated circuits .

The video encoder 200 may include an arithmetic logic unit (ALU), an elementary functional unit (EFU), a digital circuit, an analog circuit, and/or a programmable core formed of programmable circuits. In examples in which the operations of video encoder 200 are performed using software executed by programmable circuitry, memory 106 (FIG. 1) may store instructions (eg, object code) for the software received and executed by video encoder 200, Or another memory (not shown) in the video encoder 200 may store such instructions.

The video data memory 230 is configured to store the received video data. The video encoder 200 may obtain a picture of the video data from the video data memory 230 and provide the video data to the residual generation unit 204 and the mode selection unit 202 . The video data in the video data memory 230 may be the original video data to be encoded.

Mode selection unit 202 includes motion estimation unit 222 , motion compensation unit 224 and intra-frame prediction unit 226 . The mode selection unit 202 may include additional functional units to perform video prediction according to other prediction modes. As examples, mode selection unit 202 may include a palette unit, an intra-block copy unit (which may be part of motion estimation unit 222 and/or motion compensation unit 224), an affine unit, a linear model (LM) unit, and the like.

Mode selection unit 202 typically coordinates multiple encoding passes to test combinations of encoding parameters and resulting rate-distortion values for such combinations. Coding parameters may include partitioning of the CTU into CUs, prediction mode for the CU, transform type for the residual data of the CU, quantization parameters for the residual data of the CU, and the like. The mode selection unit 202 may finally select a combination of encoding parameters that has a better rate-distortion value than the other tested combinations.

The video encoder 200 may partition the pictures obtained from the video data memory 230 into a series of CTUs, and encapsulate one or more CTUs in slices. The mode selection unit 202 may divide the CTUs of the picture according to a tree structure such as the above-described QTBT structure or quad-tree structure of HEVC. As described above, the video encoder 200 may form one or more CUs by partitioning the CTUs according to the tree structure. Such CUs may also be commonly referred to as "video blocks" or "blocks."

Typically, mode selection unit 202 also controls its elements (eg, motion estimation unit 222, motion compensation unit 224, and intra-frame prediction unit 226) to generate data for the current block (eg, the current CU, or in HEVC, PUs and TUs) the overlapping portion of the prediction block). To perform inter-frame prediction on the current block, motion estimation unit 222 may perform a motion search to identify motion in one or more reference pictures (eg, one or more previously coded pictures stored in DPB 218 ). One or more closely matched reference blocks. Specifically, the motion estimation unit 222 may, for example, according to the sum of absolute differences (SAD), the sum of squared differences (SSD), the mean absolute difference (MAD), the mean square error (MSD), etc. A value for the degree of similarity to the current block. Motion estimation unit 222 may typically perform these calculations using sample-by-sample differences between the current block and the reference block under consideration. Motion estimation unit 222 may identify the reference block with the lowest value resulting from these calculations, which indicates the reference block that most closely matches the current block.

Motion estimation unit 222 may form one or more motion vectors (MVs) that define the position of the reference block in the reference picture relative to the position of the current block in the current picture. Motion estimation unit 222 may then provide the motion vector to motion compensation unit 224 . For example, for uni-directional inter-frame prediction, motion estimation unit 222 may provide a single motion vector, while for bi-directional inter-frame prediction, motion estimation unit 222 may provide two motion vectors. Subsequently, motion compensation unit 224 may use the motion vector to generate a prediction block. For example, the motion compensation unit 224 may use the motion vector to obtain the data of the reference block. As another example, if the motion vector has fractional sampling precision, motion compensation unit 224 may interpolate the values used for the prediction block according to one or more interpolation filters. Additionally, for bi-directional inter-frame prediction, motion compensation unit 224 may obtain data for two reference blocks identified by corresponding motion vectors and combine the obtained data, such as via sample-by-sample averaging or weighted averaging .

As another example, for intra-frame prediction or intra-frame prediction coding, intra-frame prediction unit 226 may generate a predicted block from samples adjacent to the current block. For example, for directional mode, intra-frame prediction unit 226 may typically mathematically combine the values of adjacent samples and fill in the calculated values in the defined direction across the current block to produce the predicted block . As another example, for DC mode, intra-frame prediction unit 226 may calculate an average of adjacent samples for the current block and generate a prediction block to include the resulting average for each sample of the prediction block.

In accordance with the techniques described above, intra-frame prediction unit 226 may be configured to construct a general most probable mode list containing N entries, wherein the N entries of the general most probable mode list are intra-frame prediction modes, and wherein the plane The pattern is the sequential first entry in the list of general most probable patterns; construct the list of primary most likely patterns from the first Np entries in the list of general most probable patterns, where Np is less than N; from the remainder of the list of general most probable patterns (N -Np) entries to construct the secondary most probable mode list; use the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current video data block; and use the current intra-frame prediction mode to encode the current block of video data to generate an encoded block of video data.

Mode selection unit 202 provides the prediction block to residual generation unit 204 . Residual generation unit 204 receives the original uncoded version of the current block from video data memory 230 and the prediction block from mode selection unit 202 . The residual generation unit 204 calculates the sample-by-sample difference between the current block and the prediction block. The resulting sample-by-sample difference defines the residual block for the current block. In some examples, residual generation unit 204 may also determine the difference between the sample values in the residual block to generate the residual block using residual differential pulse coding modulation (RDPCM). In some examples, residual generation unit 204 may be formed using one or more subtractor circuits that perform binary subtraction.

In examples in which mode selection unit 202 partitions the CU into PUs, each PU may be associated with a luma prediction unit and a corresponding chroma prediction unit. Video encoder 200 and video decoder 300 may support PUs having various sizes. As noted above, the size of the CU may represent the size of the CU's luma coding block, and the size of the PU may represent the size of the PU's luma prediction unit. Assuming the size of a particular CU is 2Nx2N, video encoder 200 may support PU sizes of 2Nx2N or NxN for intra-frame prediction, and 2Nx2N, 2NxN, Nx2N, NxN, or similar symmetric PUs for inter-frame prediction size. Video encoder 200 and video decoder 300 may also support asymmetric partitioning for PU sizes of 2NxnU, 2NxnD, nLx2N, and nRx2N for inter-frame prediction.

In examples in which mode selection unit 202 does not further partition the CU into PUs, each CU may be associated with a luma coding block and a corresponding chroma coding block. As previously described, the size of the CU may represent the size of the luma coding block of the CU. The video encoder 200 and the video decoder 300 may support a CU size of 2Nx2N, 2NxN or Nx2N.

For other video coding techniques (such as intra-block copy mode coding, affine mode coding, and linear model (LM) mode coding, to name a few), mode selection unit 202 uses corresponding unit to generate a prediction block for the current block being encoded. In some examples (such as palette mode coding), mode selection unit 202 may not generate predicted blocks, but instead generate syntax elements indicating how the blocks are to be reconstructed based on the selected palette . In such a mode, mode selection unit 202 may provide the syntax elements to entropy encoding unit 220 for encoding.

As mentioned above, the residual generation unit 204 receives video data for the current block and the corresponding prediction block. Subsequently, the residual generating unit 204 generates a residual block for the current block. To generate the residual block, the residual generation unit 204 calculates a sample-by-sample difference between the prediction block and the current block.

Transform processing unit 206 applies one or more transforms to the residual block to generate a block of transform coefficients (referred to herein as a "transform coefficient block"). Transform processing unit 206 may apply various transforms to the residual blocks to form blocks of transform coefficients. For example, transform processing unit 206 may apply a discrete cosine transform (DCT), a directional transform, a Karhunen-Loeve transform (KLT), or a conceptually similar transform to the residual block. In some examples, transform processing unit 206 may perform various transforms on the residual block, eg, primary transforms and secondary transforms (such as rotational transforms). In some examples, transform processing unit 206 does not apply a transform to the residual block.

Quantization unit 208 may quantize the transform coefficients in the transform coefficient block to generate a quantized transform coefficient block. Quantization unit 208 may quantize the transform coefficients of the block of transform coefficients according to a quantization parameter (QP) value associated with the current block. Video encoder 200 (eg, via mode selection unit 202 ) may adjust the degree of quantization applied to the transform coefficient block associated with the current block by adjusting the QP value associated with the CU. Quantization may cause a loss of information, and thus, the quantized transform coefficients may have lower precision than the original transform coefficients produced by transform processing unit 206 .

Inverse quantization unit 210 and inverse transform processing unit 212 may apply inverse quantization and inverse transform, respectively, to the quantized transform coefficient block to reconstruct a residual block from the transform coefficient block. Reconstruction unit 214 may generate a reconstructed block corresponding to the current block (albeit potentially with some degree of distortion) based on the reconstructed residual block and the predicted block generated by mode selection unit 202 . For example, reconstruction unit 214 may add samples of the reconstructed residual block to corresponding samples from the prediction block generated by mode selection unit 202 to generate a reconstructed block.

Filter unit 216 may perform one or more filter operations on the reconstructed block. For example, filter unit 216 may perform a deblocking operation to reduce blocking artifacts along the edges of the CU. In some instances, the operations of filter unit 216 may be skipped.

Video encoder 200 stores the reconstructed blocks in DPB 218 . For example, in instances in which the operations of filter unit 216 are not performed, reconstruction unit 214 may store the reconstructed block into DPB 218 . In examples in which the operations of filter unit 216 are performed, filter unit 216 may store the filtered reconstructed block into DPB 218 . Motion estimation unit 222 and motion compensation unit 224 may fetch reference pictures formed from reconstructed (and potentially filtered) blocks from DPB 218 for inter-frame prediction of blocks of subsequently encoded pictures. Additionally, intra-prediction unit 226 may use the reconstructed blocks of the current picture in DPB 218 to intra-predict other blocks in the current picture.

In general, entropy encoding unit 220 may entropy encode syntax elements received from other functional elements of video encoder 200 . For example, entropy encoding unit 220 may entropy encode the quantized block of transform coefficients from quantization unit 208. As another example, entropy encoding unit 220 may entropy encode prediction syntax elements from mode selection unit 202 (eg, motion information for inter-frame prediction or intra-frame mode information for intra-frame prediction). Entropy encoding unit 220 may perform one or more entropy encoding operations on syntax elements, which are another example of video data, to generate entropy encoded data. For example, entropy encoding unit 220 may perform context self-adjusting variable length coding (CAVLC) operations, CABAC operations, variable-to-variable (V2V) length coding operations, syntax-based context self-adjusting binary arithmetic coding (SBAC) ) operation, a probability interval partitioning entropy (PIPE) decoding operation, an exponential Golomb encoding operation, or another type of entropy encoding operation on the data. In some examples, entropy encoding unit 220 may operate in a bypass mode in which syntax elements are not entropy encoded.

Video encoder 200 may output a bitstream that includes entropy-encoded syntax elements needed to reconstruct blocks of slices or pictures. Specifically, the entropy encoding unit 220 may output a bitstream.

The above operations are described with respect to blocks. Such descriptions should be understood as operations for luma coded blocks and/or chroma coded blocks. As previously described, in some examples, the luma coding blocks and the chroma coding blocks are the luma and chroma components of a CU. In some examples, the luma coding blocks and the chroma coding blocks are the luma and chroma components of the PU.

In some examples, operations performed with respect to luma coded blocks need not be repeated for chroma coded blocks. As one example, the operations for identifying motion vectors (MVs) and reference pictures for luma coded blocks need not be repeated to identify MVs and reference pictures for chroma blocks. Rather, the MVs for luma coded blocks may be scaled to determine the MVs for chroma blocks, and the reference pictures may be the same. As another example, the intra-frame prediction procedure may be the same for luma coded blocks and chroma coded blocks.

Video encoder 200 represents an example of a device configured to encode video data, the device comprising: memory configured to store video data; and one or more processing units implemented and configured in circuitry is: constructs a general most probable mode list containing N entries, where the N entries of the general most probable mode list are intra-frame prediction modes, and where the planar mode is the sequential first entry in the general most probable mode list; from First Np entries in the general most probable pattern list construct the primary most probable pattern list, where Np is less than N; construct the secondary most probable pattern list from the remaining (N-Np) entries in the general most probable pattern list; use the main most probable pattern list a list of possible modes or a list of second most probable modes to determine the current intra-frame prediction mode for the current block of video data; and encoding the current block of video data using the current intra-frame prediction mode to generate an encoded Video data block.

6 is a block diagram illustrating an exemplary video decoder 300 that may perform the techniques of the present disclosure. FIG. 6 is provided for purposes of explanation and is not intended to limit the techniques generally illustrated and described in the context of this document. For explanatory purposes, the present disclosure describes the video decoder 300 in terms of VVC (ITU-T H.266 under development) and HEVC (ITU-T H.265) techniques. However, the techniques of this disclosure may be performed by video coding devices configured for other video coding standards.

In the example of FIG. 6, video decoder 300 includes coded picture buffer (CPB) memory 320, entropy decoding unit 302, prediction processing unit 304, inverse quantization unit 306, inverse transform processing unit 308, reconstruction unit 310, Filter unit 312 and decoded picture buffer (DPB) 314 . Any or all of CPB memory 320, entropy decoding unit 302, prediction processing unit 304, inverse quantization unit 306, inverse transform processing unit 308, reconstruction unit 310, filter unit 312, and DPB 314 may be one or more of implemented in a processor or in processing circuitry. For example, the elements of video decoder 300 may be implemented as one or more circuits or logic elements, as part of hardware circuitry, or as part of a processor, ASIC or FPGA. Furthermore, video decoder 300 may include additional or alternative processors or processing circuitry to perform these and other functions.

Prediction processing unit 304 includes motion compensation unit 316 and intra-frame prediction unit 318 . Prediction processing unit 304 may include additional units that perform predictions according to other prediction modes. As examples, prediction processing unit 304 may include a palette unit, an intra-block copy unit (which may form part of motion compensation unit 316), an affine unit, a linear model (LM) unit, and the like. In other examples, video decoder 300 may include more, fewer, or different functional elements.

CPB memory 320 may store video data, such as an encoded video bitstream, to be decoded by the components of video decoder 300 . For example, video data stored in CPB memory 320 may be obtained from computer readable medium 110 (FIG. 1). CPB memory 320 may include a CPB that stores encoded video data (eg, syntax elements) from the encoded video bitstream. In addition, CPB memory 320 may store video data other than syntax elements of the coded picture, such as temporary data used to represent outputs from various units of video decoder 300 . DPB 314 typically stores decoded pictures, which video decoder 300 may output and/or use as reference video data when decoding subsequent data or pictures of the encoded video bitstream. CPB memory 320 and DPB 314 may be formed from any of a variety of memory devices, such as DRAM, including SDRAM, MRAM, RRAM, or other types of memory devices. CPB memory 320 and DPB 314 may be provided by the same memory device or by separate memory devices. In various examples, CPB memory 320 may be on-chip with other components of video decoder 300, or off-chip relative to those components.

Additionally or alternatively, in some examples, video decoder 300 may obtain decoded video data from memory 120 (FIG. 1). That is, memory 120 may utilize CPB memory 320 to store data as discussed above. Likewise, memory 120 may store instructions to be executed by video decoder 300 when some or all of the functions of video decoder 300 are implemented in software to be executed by the processing circuitry of video decoder 300 .

The various units illustrated in FIG. 6 are illustrated to aid in understanding the operations performed by the video decoder 300 . The units may be implemented as fixed function circuits, programmable circuits, or a combination thereof. Similar to FIG. 5, fixed function circuits represent circuits that provide specific functions and are preset with respect to operations that can be performed. Programmable circuits represent circuits that can be programmed to perform various tasks and provide flexible functionality in operations that can be performed. For example, the programmable circuit may execute software or firmware that causes the programmable circuit to operate in a manner defined by the instructions of the software or firmware. Fixed-function circuits may execute software instructions (eg, to receive parameters or output parameters), but the type of operations performed by fixed-function circuits is generally immutable. In some examples, one or more of the cells may be different circuit blocks (fixed function or programmable), and in some examples, one or more of the cells may be integrated circuits .

Video decoder 300 may include ALUs, EFUs, digital circuits, analog circuits, and/or programmable cores formed from programmable circuits. In instances where the operations of video decoder 300 are performed by software executing on programmable circuitry, on-chip or off-chip memory may store instructions (eg, object code) for the software that video decoder 300 receives and executes.

Entropy coding unit 302 may receive encoded video data from the CPB and entropy decode the video data to reproduce syntax elements. Prediction processing unit 304, inverse quantization unit 306, inverse transform processing unit 308, reconstruction unit 310, and filter unit 312 may generate decoded video data based on syntax elements extracted from the bitstream.

Typically, video decoder 300 reconstructs pictures on a block-by-block basis. Video decoder 300 may perform reconstruction operations on each block individually (where the block currently being reconstructed (ie, decoded) may be referred to as the "current block").

Entropy decoding unit 302 may entropy decode syntax elements used to define the quantized transform coefficients of the quantized transform coefficient block, as well as transform information such as quantization parameters (QPs) and/or transform mode indications. Inverse quantization unit 306 may use the QP associated with the quantized transform coefficient block to determine the degree of quantization and, likewise, the degree of inverse quantization for inverse quantization unit 306 to apply. Inverse quantization unit 306 may, for example, perform a bitwise left shift operation to inverse quantize the quantized transform coefficients. Inverse quantization unit 306 may thus form transform coefficient blocks comprising transform coefficients.

After inverse quantization unit 306 forms the transform coefficient block, inverse transform processing unit 308 may apply one or more inverse transforms to the transform coefficient block to generate a residual block associated with the current block. For example, the inverse transform processing unit 308 may apply an inverse DCT, an inverse integer transform, an inverse Karhunen-Loeve transform (KLT), an inverse rotation transform, an inverse directional transform, or another inverse transform to the coefficient-of-change block.

In addition, prediction processing unit 304 generates prediction blocks from prediction information syntax elements entropy decoded by entropy decoding unit 302 . For example, motion compensation unit 316 may generate a prediction block if the prediction information syntax element indicates that the current block is inter-frame predicted. In this case, the prediction information syntax element may indicate the reference picture in DPB 314 from which the reference block is to be obtained, and is used to identify that the reference block is in reference to the current block's position in the current picture The motion vector of the position in the picture. Motion compensation unit 316 may generally perform an inter-frame prediction procedure in a manner substantially similar to that described with respect to motion compensation unit 224 (FIG. 5).

As another example, if the prediction information syntax element indicates that the current block is intra-predicted, intra-prediction unit 318 may generate the prediction block according to the intra-prediction mode indicated by the prediction information syntax element. Again, intra-frame prediction unit 318 may generally perform the intra-frame prediction procedure in a manner substantially similar to that described with respect to intra-frame prediction unit 226 (FIG. 5). In-frame prediction unit 318 may obtain data from DPB 314 for adjacent samples of the current block.

In accordance with the techniques described above, intra-frame prediction unit 318 may be configured to construct a general most probable mode list containing N entries, wherein the N entries of the general most probable mode list are intra-frame prediction modes, and wherein the planar mode is general Sequential first entry in the list of most probable patterns; construct the list of primary most likely patterns from the first Np entries in the list of general most probable patterns, where Np is less than N; from the remainder in the list of general most probable patterns (N-Np) entries to construct a secondary most probable mode list; use the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data; and use the current intra-frame prediction mode to The current video data block is decoded to generate a decoded video data block.

The reconstruction unit 310 may reconstruct the current block using the prediction block and the residual block. For example, reconstruction unit 310 may reconstruct the current block by adding samples of the residual block to corresponding samples of the prediction block.

Filter unit 312 may perform one or more filter operations on the reconstructed block. For example, filter unit 312 may perform a deblocking operation to reduce blocking artifacts along the edges of the reconstructed block. The operations of filter unit 312 are not necessarily performed in all instances.

Video decoder 300 may store the reconstructed blocks in DPB 314 . For example, in instances in which the operations of filter unit 312 are not performed, reconstruction unit 310 may store the reconstructed block into DPB 314 . In examples in which the operations of filter unit 312 are performed, filter unit 312 may store the filtered reconstructed block into DPB 314 . As discussed above, DPB 314 may provide reference information, such as the current picture for intra-frame prediction and samples of previously decoded pictures for subsequent motion compensation, to prediction processing unit 304 . Furthermore, video decoder 300 may output decoded pictures (eg, decoded video) from DPB 314 for subsequent presentation on a display device, such as display device 118 of FIG. 1 .

In this manner, video decoder 300 represents an example of a video decoding apparatus including: memory configured to store video data; and one or more processing units implemented and configured in circuitry is: constructs a general most probable mode list containing N entries, where the N entries of the general most probable mode list are intra-frame prediction modes, and where the planar mode is the sequential first entry in the general most probable mode list; from First Np entries in the general most probable pattern list construct the primary most probable pattern list, where Np is less than N; construct the secondary most probable pattern list from the remaining (N-Np) entries in the general most probable pattern list; use the main most probable pattern list a list of possible modes or a list of second most probable modes to determine the current intra-frame prediction mode for the current block of video data; and decoding the current block of video data using the current intra-frame prediction mode to generate a decoded Video data block.

7 is a flowchart illustrating an exemplary method for encoding a current block in accordance with the techniques of this disclosure. The current block may include the current CU. Although described with respect to video encoder 200 (FIGS. 1 and 5), it should be understood that other devices may be configured to perform a method similar to that of FIG.

In this example, video encoder 200 initially predicts the current block (350). For example, the video encoder 200 may form a predicted block for the current block. Subsequently, video encoder 200 may calculate a residual block for the current block (352). To calculate the residual block, the video encoder 200 may calculate the difference between the original unencoded block and the predicted block for the current block. Then, video encoder 200 may transform the residual block and quantize the transform coefficients of the residual block (354). Next, video encoder 200 may scan the residual block for the quantized transform coefficients (356). During or after the scan, video encoder 200 may entropy encode the transform coefficients (358). For example, video encoder 200 may use CAVLC or CABAC to encode transform coefficients. Video encoder 200 may then output entropy encoded data for the block (360).

8 is a flowchart illustrating an exemplary method for decoding a current block of video material in accordance with the techniques of this disclosure. The current block may include the current CU. Although described with respect to video decoder 300 (FIGS. 1 and 6), it should be understood that other devices may be configured to perform a method similar to that of FIG.

Video decoder 300 may receive entropy-encoded data for the current block (such as entropy-encoded prediction information and entropy-encoded data for transform coefficients of residual blocks corresponding to the current block) ( 370). Video decoder 300 may entropy decode the entropy encoded data to determine prediction information for the current block and reproduce transform coefficients for the residual block (372). Video decoder 300 may predict the current block (374), eg, calculate a predicted block for the current block using an intra-frame or inter-frame prediction mode indicated by the prediction information for the current block. Video decoder 300 may then inverse scan (376) the reproduced transform coefficients to create blocks of quantized transform coefficients. Subsequently, video decoder 300 may inverse quantize the transform coefficients and apply an inverse transform to the transform coefficients to generate a residual block (378). Video decoder 300 may finally decode the current block by combining the prediction block and the residual block (380).

9 is a flowchart illustrating another exemplary method for encoding a current block in accordance with the techniques of this disclosure. The techniques of FIG. 9 may be performed by one or more structural units of video encoder 200 , including intra-frame prediction unit 226 of FIG. 5 .

In one example of the present disclosure, video encoder 200 is configured to encode a current block of video data using intra-frame prediction. The video encoder 200 may be configured to construct a general most probable mode list containing N entries, where the N entries of the general most probable mode list are intra-frame prediction modes, and where the planar mode is the order in the general most probable mode list First entry (500). The video encoder 200 may also construct the primary most probable mode list from the first Np entries in the general most probable mode list, where Np is less than N (502), and from the remaining (N-Np) entries in the general most probable mode list Constructs a list of secondary most probable patterns (504). Video encoder 200 may also use the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data (506), and use the current intra-frame prediction mode to determine the current intra-frame prediction mode. The video data block is encoded to generate an encoded video data block (508). In one example, N is 22 and Np is 6.

In one example of the subject matter, the video encoder 200 may be configured to encode an index of the primary most probable mode list or the secondary most probable mode list, wherein the index indicates the primary most probable mode list or the secondary most probable mode list List of non-planar intra-frame prediction modes.

In another example of the content of the present case, in order to encode the index of the primary most probable mode list or the secondary most probable mode list, the video encoder 200 may be configured to: for entropy encoding the first bin of the index; and using the context to entropy encode the first bin of the index. In one example, the coding tool is one of a general intra-frame prediction mode, an intra-frame subpartition mode, or a multiple auxiliary line mode.

In another example, in order to construct the general most probable mode list, the video encoder 200 is also configured to: add the corresponding intra-frame prediction modes from corresponding neighboring blocks of the current video data block to the general most probable mode list and adding a plurality of intra-frame prediction modes offset from corresponding intra-frame prediction modes from corresponding neighboring blocks to the general most probable mode list. The video encoder 200 may predict corresponding intra-frame predictions from corresponding neighboring blocks of the current block of video data based on the corresponding intra-frame prediction modes being available and not yet added to the general most probable mode list The pattern is added to the general list of most probable patterns.

10 is a flowchart illustrating another exemplary method for decoding a current block in accordance with the techniques of this disclosure. The techniques of FIG. 10 may be performed by one or more structural units of video decoder 300 , including intra-frame prediction unit 318 of FIG. 6 .

In one example of the subject matter, video decoder 300 may be configured to decode the current block of video data using intra-frame prediction. Video decoder 300 may be configured to construct a general most probable mode list containing N entries, where the N entries of the general most probable mode list are intra-frame prediction modes, and where the planar mode is the order in the general most probable mode list First entry (600). The video decoder 300 may also construct the primary most probable mode list from the first Np entries in the general most probable mode list, where Np is less than N (602), and from the remaining (N-Np) entries in the general most probable mode list Constructs a list of second most probable modes (604). Then, video decoder 300 may use the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data (606), and use the current intra-frame prediction mode to The current block of video data is decoded to generate a decoded block of video data (608). In one example, N is 22 and Np is 6.

In one example, in order to determine the current intra-frame prediction mode, the video decoder 300 may also be configured to: decode an index of the primary most probable mode list or the secondary most probable mode list, where the index indicates the primary most probable mode The non-planar intra-frame prediction modes in the list or the LLM list. The video decoder 300 may determine the current intra-frame prediction mode for the current block of video data based on the index.

In another example, in order to decode the index of the primary most probable mode list or the secondary most probable mode list, the video decoder 300 may also decide to use the first index for the index based on the coding tool used for the current block. A context for entropy decoding of one bin, and the context is used to entropy decode the first bin of the index. In one example, the coding tool is one of a general intra-frame prediction mode, an intra-frame subpartition mode, or a multiple auxiliary line mode.

In another example of the subject matter, in order to construct the general most probable mode list, the video decoder 300 may be configured to: add the corresponding intra-frame prediction modes from the corresponding neighboring blocks of the current video data block to the and adding to the general most probable mode list a plurality of intra-frame prediction modes offset from corresponding intra-frame prediction modes from corresponding neighboring blocks. In one example, video decoder 300 may convert corresponding blocks from corresponding neighboring blocks of the current block of video data to In-frame prediction mode is added to the list of general most probable modes.

In another example, in order to use the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data, the video decoder 300 may be configured to: decoding the syntax elements of the current most probable mode list of the most probable mode list or the second most probable mode list; decoding the index into the current most probable mode list; and determining the current intra-frame prediction mode according to the index of the current most probable mode list .

Additional aspects of the content of this case are described below.

Aspect 1A - A method of decoding video data, the method comprising the steps of: constructing a general most probable mode list comprising N entries, wherein the N entries of the general most probable mode list are intra-frame prediction modes ; construct a primary most probable pattern list from the first Np entries in this general most probable pattern list, where Np is less than N; construct a secondary most probable pattern list from the remaining (N-Np) entries in this general most probable pattern list ; and use the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data.

Aspect 2A - The method of Aspect 1A, wherein N is 22 and Np is 6.

Aspect 3A—The method of any one of Aspects 1A and 2A, wherein constructing the general most probable mode list comprises: adding a planar mode as a sequential first entry in the general most probable mode list; adding the corresponding intra-frame prediction modes of corresponding neighboring blocks of the data block to the general most probable mode list; and from the corresponding intra-frame prediction modes from the corresponding neighboring blocks The offset intra-frame prediction mode is added to the list of general most probable modes.

Aspect 4A—The method of Aspect 3A, wherein adding the corresponding intra-frame prediction modes from the corresponding neighboring blocks of the current block of video data to the general MPM list comprises: If the corresponding intra-frame prediction modes are available and have not been added to the general most probable mode list, then the corresponding information from the corresponding neighboring blocks of the current video data block is In-box prediction modes are added to this list of general most probable modes.

Aspect 5A—The method of any of Aspects 1A-4A, further comprising the step of: determining a non-planar mode for indicating the list of primary most probable modes based on a coding tool for the current block The index of the decoding context.

Aspect 6A—The method of Aspect 5A, wherein the coding tool is one of general intra-frame prediction, sub-partitioning, or multiple auxiliary lines.

Aspect 7A—The method of any of Aspects 1A-6A, wherein decoding comprises decoding.

Aspect 8A - The method of any of Aspects 1A-7A, wherein decoding comprises encoding.

Aspect 9A - An apparatus for decoding video data, the apparatus comprising one or more means for performing the method according to any of Aspects 1A-8A.

Aspect 10A - The apparatus of Aspect 9A, wherein the one or more components comprise one or more processors implemented in circuitry.

Aspect 11A - The apparatus of any of Aspects 9A and 10A, further comprising memory for storing the video data.

Aspect 12A - The apparatus of any of Aspects 9A-11A, further comprising a display configured to display the decoded video data.

Aspect 13A - The apparatus of any of Aspects 9A-12A, wherein the apparatus comprises one or more of a camera, a computer, a mobile device, a broadcast receiver device, or a set-top box.

Aspect 14A - The apparatus of any of Aspects 9A-13A, wherein the apparatus includes a video decoder.

Aspect 15A - The apparatus of any of Aspects 9A-14A, wherein the apparatus comprises a video encoder.

Aspect 16A - A computer-readable storage medium having instructions stored thereon that, when executed, cause one or more processors to perform the method according to any of Aspects 1A-8A.

Aspect 1B - A method of decoding video data, the method comprising the steps of: constructing a general MPC list comprising N entries, wherein the N entries of the general MPM list are intra-frame prediction modes, and where the flat mode is the sequential first entry in the general most probable mode list; construct the main most probable mode list from the first Np entries in the general most probable mode list, where Np is less than N; from the general most probable mode list The remaining (N-Np) entries in the list construct a secondary most probable mode list; use either the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data ; and decoding the current block of video data using the current intra-frame prediction mode to generate a decoded block of video data.

Aspect 2B—the method of Aspect 1B, wherein determining the current intra-frame prediction mode further comprises: decoding an index to the primary most probable mode list or the secondary most probable mode list, wherein the index indicates the primary most probable mode list a non-planar intra-frame prediction mode in the list of possible modes or the list of second most probable modes; and determining the current intra-frame prediction mode for the current block of video data based on the index.

Aspect 3B—The method of Aspect 2B, wherein decoding the index of the primary most probable mode list or the secondary most probable mode list comprises: determining, based on a coding tool for the current block A context for entropy decoding the first bin of the index; and using the context to entropy decode the first bin of the index.

Aspect 4B—The method of Aspect 3B, wherein the coding tool is one of a normal intra-frame prediction mode, an intra-frame sub-partition mode, or a multiple auxiliary line mode.

Aspect 5B—The method of Aspect 1B, wherein N is 22 and Np is 6.

Aspect 6B—The method of Aspect 1B, wherein constructing the general most probable mode list comprises: adding to the general most probable mode corresponding intra-frame prediction modes from corresponding neighboring blocks of the current block of video data and adding to the general most probable mode list a plurality of intra-frame prediction modes offset from the corresponding intra-frame prediction modes from the corresponding neighboring blocks.

Aspect 7B—The method of Aspect 6B, wherein adding the corresponding intra-frame prediction modes from the corresponding neighboring blocks of the current block of video data to the general MPM list comprises: The corresponding information from the corresponding neighboring blocks of the current block of video data are combined based on the corresponding intra-frame prediction modes that are available and have not been added to the general most probable mode list In-box prediction modes are added to this list of general most probable modes.

Aspect 8B—The method of Aspect 1B, wherein using the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data comprises: decoding the syntax element of the current most probable mode list of the primary most probable mode list or the secondary most probable mode list; decoding the index of the current most probable mode list; and according to the index of the current most probable mode list Determines the current in-frame prediction mode.

Aspect 9B—The method of Aspect 1B, further comprising the step of: displaying a picture including the decoded block of video data.

Aspect 10B - An apparatus configured to decode video data, the apparatus comprising: a memory configured to store a current block of video data; and an or a circuit implemented in circuitry and in communication with the memory a plurality of processors, the one or more processors configured to: construct a general most probable mode list comprising N entries, wherein the N entries of the general most probable mode list are intra-frame prediction modes, and wherein the plane pattern is the first entry in the order of the general most probable pattern list; construct the main most likely pattern list from the first Np entries in the general most probable pattern list, where Np is less than N; from the general most probable pattern list The remaining (N-Np) entries construct a secondary most probable mode list; use the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data; and use The current intra-frame prediction mode is used to decode the current block of video data to generate a decoded block of video data.

Aspect 11B—the apparatus of Aspect 10B, wherein to determine the current intra-frame prediction mode, the one or more processors are also configured to: a decoding an index, wherein the index indicates a non-planar intra-frame prediction mode in the primary most probable mode list or the secondary most probable mode list; and determining the current information for the current block of video data based on the index In-box prediction mode.

Aspect 12B—the apparatus of Aspect 11B, wherein in order to decode the index of the primary most probable mode list or the secondary most probable mode list, the one or more processors are also configured to: the coding tool of the current block to determine the context for entropy decoding the first bin of the index; and

The first bin of the index is entropy decoded using the context.

Aspect 13B—the device of Aspect 12B, wherein the coding tool is one of a normal intra-frame prediction mode, an intra-frame subpartition mode, or a multiple helpline mode.

Aspect 14B—the device of Aspect 10B, wherein N is 22 and Np is 6.

Aspect 15B—the apparatus of Aspect 10B, wherein to construct the general most probable mode list, the one or more processors are also configured to: combine corresponding data from corresponding neighboring blocks of the current block of video data adding the intra-frame prediction modes of The general most probable mode list.

Aspect 16B—the apparatus of Aspect 15B, wherein in order to add the corresponding intra-frame prediction modes from the corresponding neighboring blocks of the current block of video data to the general most probable mode list, The one or more processors are also configured to: based on the corresponding intra-frame prediction modes are available and have not been added to the general most probable mode list, to the current video data block from the The corresponding intra-frame prediction modes of the corresponding neighboring blocks are added to the general most probable mode list.

Aspect 17B—the apparatus of Aspect 10B, wherein in order to use the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data, the one or The plurality of processors are also configured to: decode a syntax element indicating a current most probable mode list from the primary most probable mode list or the secondary most probable mode list; decode an index to the current most probable mode list; and determining the current intra-frame prediction mode according to the index of the current most probable mode list.

Aspect 18B—The device of Aspect 10B, further comprising: a display configured to display a picture including the decoded block of video data.

Aspect 19B - An apparatus configured to decode video material, the apparatus comprising: means for constructing a general most probable mode list comprising N entries, wherein the N entries of the general most probable mode list are information In-box prediction mode, and where the planar mode is the ordinal first entry in the general most probable mode list; means for constructing the primary most probable mode list from the first Np entries in the general most probable mode list, where Np less than N; a member for constructing a secondary most probable mode list from the remaining (N-Np) entries in the general most probable mode list; for using the primary most probable mode list or the secondary most probable mode list to means for determining a current intra-frame prediction mode for a current block of video data; and means for decoding the current block of video data using the current intra-frame prediction mode to generate a decoded block of video data member.

Aspect 20B—the apparatus of Aspect 19B, wherein the means for determining the current intra-frame prediction mode further comprises: means for decoding an index to the primary most probable mode list or the secondary most probable mode list means, wherein the index indicates a non-planar intra-frame prediction mode in the primary most probable mode list or the secondary most probable mode list; and for determining the current information for the current block of video data based on the index The building blocks of the in-box prediction mode.

Aspect 21B—the apparatus of Aspect 20B, wherein the means for decoding the index of the primary most probable mode list or the secondary most probable mode list comprises: based on the decoding for the current block means for determining a context for entropy decoding the first bin of the index; and means for entropy decoding the first bin of the index using the context.

Aspect 22B - A non-transitory computer-readable storage medium storing instructions that, when executed, cause one or more processors configured to decode video data to: construct a structure comprising N entries , where the N entries of the general most probable mode list are intra-frame prediction modes, and where the planar mode is the sequential first entry in the general most probable mode list; from the general most probable mode list First Np entries in the pattern list construct the primary most probable pattern list, where Np is less than N; construct the secondary most probable pattern list from the remaining (N-Np) entries in this general most probable pattern list; use the primary most probable pattern list a mode list or the second most probable mode list to determine the current intra-frame prediction mode for the current block of video data; and decoding the current block of video data using the current intra-frame prediction mode to generate a Decoded video data block.

Aspect 23B—the non-transitory computer-readable storage medium of Aspect 22B, wherein in order to determine the current in-frame prediction mode, the instructions also cause the one or more processors to: decoding an index of the list of possible modes or the list of secondary most probable modes, wherein the index indicates a non-planar intra-frame prediction mode in the list of primary most probable modes or the list of secondary most probable modes; and determining based on the index the current intra-frame prediction mode for the current block of video data.

Aspect 24B—the non-transitory computer-readable storage medium according to Aspect 23B, wherein the instructions also cause the one or a plurality of processors: determine a context for entropy decoding the first bin of the index based on the coding tool for the current block; and use the context to perform the entropy decoding on the first bin of the index Entropy decoding.

Aspect 25B - an apparatus configured to encode video data, the apparatus comprising: a memory configured to store a current block of video data; and an or a circuit implemented in circuitry and in communication with the memory a plurality of processors, the one or more processors configured to: construct a general most probable mode list comprising N entries, wherein the N entries of the general most probable mode list are intra-frame prediction modes, and wherein the plane pattern is the first entry in the order of the general most probable pattern list; construct the main most likely pattern list from the first Np entries in the general most probable pattern list, where Np is less than N; from the general most probable pattern list The remaining (N-Np) entries construct a secondary most probable mode list; use the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data; and use The current intra-frame prediction mode encodes the current block of video data to generate an encoded block of video data.

Aspect 26B—the apparatus of Aspect 25B, wherein the one or more processors are also configured to: encode an index to the primary most probable mode list or the secondary most probable mode list, wherein the index indicates the primary most probable mode list The most probable mode list or the non-planar intra-frame prediction modes in the second most probable mode list.

Aspect 27B—the apparatus of Aspect 26B, wherein in order to encode the index of the primary most probable mode list or the secondary most probable mode list, the one or more processors are also configured to: The coding tool of the current block determines a context for entropy encoding the first bin of the index; and uses the context to entropy encode the first bin of the index.

Aspect 28B—the device of Aspect 27B, wherein the coding tool is one of a normal intra-frame prediction mode, an intra-frame subpartition mode, or a multiple helpline mode.

Aspect 29B—the device of Aspect 25B, wherein N is 22 and Np is 6.

Aspect 30B—the apparatus of Aspect 25B, wherein to construct the general most probable mode list, the one or more processors are also configured to: adding the intra-frame prediction modes of The general most probable mode list.

Aspect 31B—the device of Aspect 25B, wherein in order to add the corresponding intra-frame prediction modes from the corresponding neighboring blocks of the current video data block to the general most probable mode list, The one or more processors are also configured to: based on the corresponding intra-frame prediction modes are available and have not been added to the general most probable mode list, to the current video data block from the The corresponding intra-frame prediction modes of the corresponding neighboring blocks are added to the general most probable mode list.

Aspect 32B—the apparatus of aspect 25B, further comprising: a camera configured to capture a picture including the current block of video data.

Aspect 1C - A method of decoding video data, the method comprising the steps of: constructing a general most probable mode list comprising N entries, wherein the N entries of the general most probable mode list are intra-frame prediction modes, and where the flat mode is the sequential first entry in the general most probable mode list; construct the main most probable mode list from the first Np entries in the general most probable mode list, where Np is less than N; from the general most probable mode list The remaining (N-Np) entries in the list construct a secondary most probable mode list; use either the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data ; and decoding the current block of video data using the current intra-frame prediction mode to generate a decoded block of video data.

Aspect 2C—the method of aspect 1C, wherein determining the current intra-frame prediction mode further comprises: decoding an index to the primary most probable mode list or the secondary most probable mode list, wherein the index indicates the primary most probable mode list a non-planar intra-frame prediction mode in the list of possible modes or the list of second most probable modes; and determining the current intra-frame prediction mode for the current block of video data based on the index.

Aspect 3C—The method of Aspect 2C, wherein decoding the index of the primary most probable mode list or the secondary most probable mode list comprises: determining, based on a coding tool for the current block A context for entropy decoding the first bin of the index; and using the context to entropy decode the first bin of the index.

Aspect 4C—The method of Aspect 3C, wherein the coding tool is one of a normal intra-frame prediction mode, an intra-frame subpartition mode, or a multiple auxiliary line mode.

Aspect 5C - The method of any of Aspects 1C-4C, wherein N is 22 and Np is 6.

Aspect 6C—The method of any of Aspects 1C-5C, wherein constructing the general most probable mode list comprises: converting corresponding intra-frame prediction modes from corresponding neighboring blocks of the current block of video data adding to the general most probable mode list; and adding to the general most probable mode list a plurality of intra-frame prediction modes offset from the corresponding intra-frame prediction modes from the corresponding neighboring blocks middle.

Aspect 7C—The method of Aspect 6C, wherein adding the corresponding intra-frame prediction modes from the corresponding neighboring blocks of the current block of video data to the general MPM list comprises: The corresponding information from the corresponding neighboring blocks of the current block of video data are combined based on the corresponding intra-frame prediction modes that are available and have not been added to the general most probable mode list In-box prediction modes are added to this list of general most probable modes.

Aspect 8C—The method of any of Aspects 1C-7C, wherein the current in-frame prediction for the current block of video data is determined using the primary most probable mode list or the secondary most probable mode list Modes include: decoding a syntax element indicating a current most probable mode list from the primary most probable mode list or the secondary most probable mode list; decoding an index to the current most probable mode list; and according to the current most probable mode list The index of the mode list determines the current intra-frame prediction mode.

Aspect 9C—The method of any of Aspects 1C-8C, further comprising the step of displaying a picture including the decoded block of video data.

Aspect 10C - an apparatus configured to decode video data, the apparatus comprising: a memory configured to store a current block of video data; and an or a circuit implemented in circuitry and in communication with the memory a plurality of processors, the one or more processors configured to: construct a general most probable mode list comprising N entries, wherein the N entries of the general most probable mode list are intra-frame prediction modes, and wherein the plane pattern is the first entry in the order of the general most probable pattern list; construct the main most likely pattern list from the first Np entries in the general most probable pattern list, where Np is less than N; from the general most probable pattern list The remaining (N-Np) entries construct a secondary most probable mode list; use the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data; and use The current intra-frame prediction mode is used to decode the current block of video data to generate a decoded block of video data.

Aspect 11C—the apparatus of aspect 10C, wherein to determine the current intra-frame prediction mode, the one or more processors are also configured to: decoding an index, wherein the index indicates a non-planar intra-frame prediction mode in the primary most probable mode list or the secondary most probable mode list; and determining the current information for the current block of video data based on the index In-box prediction mode.

Aspect 12C—the apparatus of Aspect 11C, wherein in order to decode the index of the primary most probable mode list or the secondary most probable mode list, the one or more processors are also configured to: the coding tool for the current block of video data to determine the context for entropy decoding of the first bin of the index; and

The first bin of the index is entropy decoded using the context.

Aspect 13C—the device of Aspect 12C, wherein the coding tool is one of a normal intra-frame prediction mode, an intra-frame subpartition mode, or a multiple helpline mode.

Aspect 14C - The device of any of Aspects 10C-13C, wherein N is 22 and Np is 6.

Aspect 15C—The apparatus of any of Aspects 10C-14C, wherein to construct the general most probable mode list, the one or more processors are also configured to: convert corresponding data from the current block of video data adding corresponding intra-frame prediction modes of adjacent blocks to the general most likely mode list; and a plurality of signals offset from the corresponding intra-frame prediction modes from the corresponding adjacent blocks In-box prediction modes are added to this list of general most probable modes.

Aspect 16C—the apparatus of Aspect 15C, wherein in order to add the corresponding intra-frame prediction modes from the corresponding neighboring blocks of the current block of video data to the general most probable mode list, The one or more processors are also configured to: based on the corresponding intra-frame prediction modes are available and have not been added to the general most probable mode list, to the current video data block from the The corresponding intra-frame prediction modes of the corresponding neighboring blocks are added to the general most probable mode list.

Aspect 17C—The apparatus of any of Aspects 10C-16C, wherein in order to use the primary most probable mode list or the secondary most probable mode list to determine within the current frame for the current block of video data a prediction mode, the one or more processors are also configured to: decode a syntax element indicating a current most probable mode list from the primary most probable mode list or the secondary most probable mode list; the current most probable mode decoding the index of the list; and determining the current intra-frame prediction mode according to the index of the current most probable mode list.

Aspect 18C - The apparatus of any of Aspects 10C-17C, further comprising: a display configured to display a picture including the decoded block of video data.

Aspect 19C - an apparatus configured to encode video data, the apparatus comprising: a memory configured to store a current block of video data; and an or a circuit implemented in circuitry and in communication with the memory a plurality of processors, the one or more processors configured to: construct a general most probable mode list comprising N entries, wherein the N entries of the general most probable mode list are intra-frame prediction modes, and wherein the plane pattern is the first entry in the order of the general most probable pattern list; construct the main most likely pattern list from the first Np entries in the general most probable pattern list, where Np is less than N; from the general most probable pattern list The remaining (N-Np) entries construct a secondary most probable mode list; use the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data; and use The current intra-frame prediction mode encodes the current block of video data to generate an encoded block of video data.

Aspect 20C—the apparatus of Aspect 19C, wherein the one or more processors are also configured to: encode an index to the primary most probable mode list or the secondary most probable mode list, wherein the index indicates the primary most probable mode list The most probable mode list or the non-planar intra-frame prediction modes in the second most probable mode list.

Aspect 21C—the apparatus of aspect 20C, wherein in order to encode the index of the primary most probable mode list or the secondary most probable mode list, the one or more processors are also configured to: The coding tool of the current block of video data determines a context for entropy encoding the first bin of the index; and uses the context to entropy encode the first bin of the index.

Aspect 22C—the device of Aspect 21C, wherein the coding tool is one of a normal intra-frame prediction mode, an intra-frame subpartition mode, or a multiple helpline mode.

Aspect 23C - The device of any of Aspects 19C-22C, wherein N is 22 and Np is 6.

Aspect 24C—The apparatus of any one of Aspects 19C-23C, wherein to construct the general most likely mode list, the one or more processors are also configured to: convert corresponding data from the current block of video data adding corresponding intra-frame prediction modes of adjacent blocks to the general most likely mode list; and a plurality of signals offset from the corresponding intra-frame prediction modes from the corresponding adjacent blocks In-box prediction modes are added to this list of general most probable modes.

Aspect 25C—the apparatus of any of Aspects 19C-24C, wherein in order to add the corresponding intra-frame prediction modes from the corresponding neighboring blocks of the current block of video data to the general In the list of most probable modes, the one or more processors are also configured to: based on the corresponding intra-frame prediction modes are available and have not been added to the list of general most probable modes. The corresponding intra-frame prediction modes of the corresponding neighboring blocks of the data block are added to the general most probable mode list.

Aspect 26C—The apparatus of any of Aspects 19C-25C, further comprising: a camera configured to capture a picture including the current block of video data.

It is recognized that, depending on the example, certain acts or events of any of the techniques described herein may be performed in a different order, may be added, combined, or omitted entirely (eg, not all described acts or events are technology is necessary). Furthermore, in some instances, actions or events may be performed concurrently rather than sequentially, eg, via multi-threaded processing, interrupt processing, or multiple processors.

In one or more examples, the functions described can be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium and executed by a hardware-based processing unit. Computer-readable media may include computer-readable storage media, which correspond to tangible media, such as data storage media, or communication media, including, for example, in accordance with communication protocols that facilitate the transfer of computer programs from one place to another any media in place. In this manner, computer-readable media may generally correspond to (1) non-transitory tangible computer-readable storage media, or (2) communication media such as a signal or carrier wave. Data storage media can be any available media that can be accessed by one or more computers or one or more processors to obtain instructions, code and/or data structures for implementing the techniques described in this context. The computer program product may include a computer-readable medium.

By way of example and not limitation, such computer-readable storage media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, flash memory, or capable of Store the desired code in the form of instructions or data structures and any other medium that can be accessed by the computer. Also, any connection is properly termed a computer-readable medium. For example, if coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies (eg, infrared, radio, and microwave) are used to transmit commands from a website, server, or other remote source, coaxial cable, fiber optic cable, or Fiber optic cable, twisted pair, DSL, or wireless technologies (eg, infrared, radio, and microwave) are included in the definition of media. It should be understood, however, that computer-readable storage media and data storage media do not include connections, carrier waves, signals, or other transitory media, but are instead directed to non-transitory, tangible storage media. As used herein, magnetic and optical discs include compact discs (CDs), laser discs, optical discs, digital versatile discs (DVDs), floppy discs, and blu-ray discs, where magnetic discs generally reproduce data magnetically, while optical discs use lasers to reproduce data Optically reproduce material. Combinations of the above should also be included within the scope of computer-readable media.

Instructions may be executed by one or more processors, such as one or more DSPs, general purpose microprocessors, ASICs, FPGAs, or other equivalent integrated or individual logic circuitry. Accordingly, the terms "processor" and "processing circuitry" as used herein may represent any of the foregoing structures or any other structure suitable for implementing the techniques described herein. Additionally, in some aspects, the functionality described herein may be provided within dedicated hardware and/or software modules configured for encoding and decoding, or incorporated into a combined transcoder. Furthermore, the techniques may be implemented entirely in one or more circuits or logic elements.

The techniques disclosed herein can be implemented in a wide variety of devices or devices, including a wireless handset, an integrated circuit (IC), or a set of ICs (eg, a chip set). Various elements, modules, or units are described in this context to emphasize functional aspects of devices configured to perform the disclosed techniques, but do not necessarily require implementation via distinct hardware units. Rather, various units may be combined in a transcoder hardware unit, as previously described, or by a collection of interoperable hardware units (including one or more processors as previously described) in combination with appropriate software and/or or firmware.

Various examples have been described. These and other examples are within the scope of the appended claims.

100: Video Encoding and Decoding Systems 102: Source Device 104: Video source 106: Memory 108: Output interface 110: Computer-readable media 112: Storage Devices 114: file server 116: destination device 118: Display device 120: memory 122: Input interface 130: Quadtree Binary Tree (QTBT) Structure 132: Decoding Tree Unit (CTU) 200: Video encoder 202: Mode selection unit 204: Residual generation unit 206: Transform processing unit 208: Quantization unit 210: Inverse Quantization Unit 212: Inverse transform processing unit 214: Refactoring Unit 216: Filter unit 218: Decoded Picture Buffer (DPB) 220: Entropy coding unit 222: Motion Estimation Unit 224: Motion Compensation Unit 226: In-frame prediction unit 230: Video data memory 300: Video Decoder 302: Entropy decoding unit 304: Prediction Processing Unit 306: Inverse Quantization Unit 308: Inverse transform processing unit 310: Refactoring Unit 312: Filter unit 314: Decoded Picture Buffer (DPB) 316: Motion Compensation Unit 318: In-frame prediction unit 320: CPB memory 350: Steps 352: Steps 354: Steps 356: Steps 358: Steps 360: Steps 370: Steps 372: Steps 374: Steps 376: Steps 378: Steps 380: Steps 400:CU 402:CU 500: Steps 502: Step 504: Step 506: Steps 508: Steps 600: Steps 602: Step 604: Step 606: Steps 608: Steps A: Above AL: top left AR: top right BL: Bottom left L: left

1 is a block diagram illustrating an exemplary video encoding and decoding system that may implement the techniques of the present disclosure.

2 is a conceptual diagram illustrating an example of a neighboring block for deriving the most likely pattern list.

3 is a conceptual diagram illustrating another example of neighboring blocks for deriving the most likely pattern list.

4A and 4B are conceptual diagrams illustrating an example quadtree binary tree (QTBT) structure and corresponding coding tree unit (CTU).

5 is a block diagram illustrating an exemplary video encoder that may perform the techniques of the present disclosure.

6 is a block diagram illustrating an exemplary video decoder that may perform the techniques of the present disclosure.

7 is a flowchart illustrating an exemplary method for encoding a current block in accordance with the techniques of this disclosure.

8 is a flowchart illustrating an exemplary method for decoding a current block in accordance with the techniques of this disclosure.

9 is a flowchart illustrating another exemplary method for encoding a current block in accordance with the techniques of this disclosure.

10 is a flowchart illustrating another exemplary method for decoding a current block in accordance with the techniques of this disclosure.

Domestic storage information (please note in the order of storage institution, date and number) none Foreign deposit information (please note in the order of deposit country, institution, date and number) none

600: Steps

602: Step

604: Step

606: Steps

608: Steps

Claims (32)

A method for decoding video information, the method comprising the following steps: constructs a general most probable mode list containing N entries, wherein the N entries of the general most probable mode list are intra-frame prediction modes, and wherein a planar mode is an order first in the general most probable mode list entry; constructs a primary most probable mode list from a first Np entries in the general most probable mode list, where Np is less than N; construct a secondary most probable mode list from a remaining (N-Np) entries in the general most probable mode list; using the primary most probable mode list or the secondary most probable mode list to determine a current intra-frame prediction mode for a current block of video data; and The current block of video data is decoded using the current intra-frame prediction mode to generate a decoded block of video data. The method of claim 1, wherein the step of determining the current intra-frame prediction mode also includes the following steps: decoding an index of the PML list or the LMP list, wherein the index indicates a non-planar intra-frame prediction mode in the LMP list or the LPM list; and The current intra-frame prediction mode for the current block of video data is determined based on the index. The method of claim 2, wherein the step of decoding the index of the primary most probable mode list or the secondary most probable mode list comprises the steps of: determining a context for entropy decoding of a first bin of the index based on a coding tool for the current block of video data; and The first bin of the index is entropy decoded using the context. The method of claim 3, wherein the coding tool is one of a general intra-frame prediction mode, an intra-frame subpartition mode, or a multiple auxiliary line mode. The method of claim 1, wherein N is 22 and Np is 6. The method of claim 1, wherein the step of constructing the list of general most probable patterns comprises the steps of: adding corresponding intra-frame prediction modes from corresponding neighboring blocks of the current block of video data to the general most probable mode list; and A plurality of intra-frame prediction modes offset from the corresponding intra-frame prediction modes from the corresponding neighboring blocks are added to the general most probable mode list. The method of claim 6, wherein the step of adding the corresponding intra-frame prediction modes from the corresponding neighboring blocks of the current block of video data to the general most probable mode list comprises the steps of: The corresponding information from the corresponding neighboring blocks of the current block of video data are combined based on the corresponding intra-frame prediction modes that are available and have not been added to the general most probable mode list In-box prediction modes are added to this list of general most probable modes. The method of claim 1, wherein the step of using the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data comprises the steps of: decoding a syntax element indicating a current most probable mode list from the primary most probable mode list or the secondary most probable mode list; decoding an index into the current list of most probable patterns; and The current intra-frame prediction mode is determined according to the index of the current most probable mode list. The method of claim 1, further comprising the step of: displaying a picture including the decoded block of video data. An apparatus configured to decode video data, the apparatus comprising: a memory configured to store a current block of video data; and One or more processors implemented in circuitry and in communication with the memory, the one or more processors configured to: constructs a general most probable mode list containing N entries, wherein the N entries of the general most probable mode list are intra-frame prediction modes, and wherein a planar mode is an order first in the general most probable mode list entry; constructs a primary most probable mode list from a first Np entries in the general most probable mode list, where Np is less than N; construct a secondary most probable mode list from a remaining (N-Np) entries in the general most probable mode list; using the primary most probable mode list or the secondary most probable mode list to determine a current intra-frame prediction mode for a current block of video data; and The current block of video data is decoded using the current intra-frame prediction mode to generate a decoded block of video data. The apparatus of claim 10, wherein in order to determine the current intra-frame prediction mode, the one or more processors are also configured to: decoding an index of the PML list or the LMP list, wherein the index indicates a non-planar intra-frame prediction mode in the LMP list or the LPM list; and The current intra-frame prediction mode for the current block of video data is determined based on the index. The apparatus of claim 11, wherein in order to decode the index of the primary most probable mode list or the secondary most probable mode list, the one or more processors are also configured to: determining a context for entropy decoding of a first bin of the index based on a coding tool for the current block of video data; and The first bin of the index is entropy decoded using the context. The apparatus of claim 12, wherein the coding tool is one of a normal intra-frame prediction mode, an intra-frame sub-partition mode, or a multiple auxiliary line mode. The apparatus of claim 10, wherein N is 22 and Np is 6. The apparatus of claim 10, wherein to construct the general most probable mode list, the one or more processors are also configured to: adding corresponding intra-frame prediction modes from corresponding neighboring blocks of the current block of video data to the general most probable mode list; and A plurality of intra-frame prediction modes offset from the corresponding intra-frame prediction modes from the corresponding neighboring blocks are added to the general most probable mode list. The apparatus of claim 15, wherein in order to add the corresponding intra-frame prediction modes from the corresponding neighboring blocks of the current block of video data to the general most probable mode list, the one or more a processor is also configured to: based on the corresponding intra-frame prediction modes are available and have not been added to the general most probable mode list, the corresponding neighbors from the current video data block The corresponding intra-frame prediction modes of the block are added to the list of general most probable modes. The apparatus of claim 10, wherein in order to use the primary most probable mode list or the secondary most probable mode list to determine the current intra-frame prediction mode for the current block of video data, the one or more processors is also configured as: decoding a syntax element indicating a current most probable mode list from the primary most probable mode list or the secondary most probable mode list; decoding an index into the current list of most probable patterns; and The current intra-frame prediction mode is determined according to the index of the current most probable mode list. An apparatus according to claim 10, further comprising: A display configured to display a picture including the decoded block of video data. An apparatus configured to decode video data, the apparatus comprising: Means for constructing a general most probable mode list containing N entries, wherein the N entries of the general most probable mode list are intra-frame prediction modes, and wherein a planar mode is in the general most probable mode list a sequential first entry; means for constructing a primary most probable mode list from a first Np entries in the general most probable mode list, where Np is less than N; means for constructing a secondary most probable mode list from a remaining (N-Np) entries in the general most probable mode list; means for using the primary most probable mode list or the secondary most probable mode list to determine a current intra-frame prediction mode for a current block of video data; and Means for decoding the current block of video data using the current intra-frame prediction mode to generate a decoded block of video data. The apparatus of claim 19, wherein the means for determining the current intra-frame prediction mode further comprises: means for decoding an index of the primary most probable mode list or the secondary most probable mode list, wherein the index indicates a non-planar frame in the primary most probable mode list or the secondary most probable mode list intra-prediction mode; and Means for determining the current intra-frame prediction mode for the current block of video data based on the index. The apparatus of claim 20, wherein the means for decoding the index of the primary most probable mode list or the secondary most probable mode list comprises: means for determining a context for entropy decoding a first bin of the index based on a coding tool for the current block of video data; and Means for entropy decoding the first bin of the index using the context. A non-transitory computer-readable storage medium storing instructions that, when executed, cause one or more processors configured to decode video data to: constructs a general most probable mode list containing N entries, wherein the N entries of the general most probable mode list are intra-frame prediction modes, and wherein a planar mode is an order first in the general most probable mode list entry; constructs a primary most probable mode list from a first Np entries in the general most probable mode list, where Np is less than N; construct a secondary most probable mode list from a remaining (N-Np) entries in the general most probable mode list; using the primary most probable mode list or the secondary most probable mode list to determine a current intra-frame prediction mode for a current block of video data; and The current block of video data is decoded using the current intra-frame prediction mode to generate a decoded block of video data. The non-transitory computer-readable storage medium of claim 22, wherein in order to determine the current in-frame prediction mode, the instructions also cause the one or more processors to: decoding an index of the PML list or the LMP list, wherein the index indicates a non-planar intra-frame prediction mode in the LMP list or the LPM list; and The current intra-frame prediction mode for the current block of video data is determined based on the index. The non-transitory computer-readable storage medium of claim 23, wherein the instructions also cause the one or more processors to decode the index of the primary most probable mode list or the secondary most probable mode list Do the following: determining a context for entropy decoding of a first bin of the index based on a coding tool for the current block of video data; and The first bin of the index is entropy decoded using the context. An apparatus configured to encode video data, the apparatus comprising: a memory configured to store a current block of video data; and One or more processors implemented in circuitry and in communication with the memory, the one or more processors configured to: constructs a general most probable mode list containing N entries, wherein the N entries of the general most probable mode list are intra-frame prediction modes, and wherein a planar mode is an order first in the general most probable mode list entry; construct a list of major most probable modes from a first Np entries in the general list of most probable modes, where Np is less than N; construct a secondary most probable mode list from a remaining (N-Np) entries in the general most probable mode list; using the primary most probable mode list or the secondary most probable mode list to determine a current intra-frame prediction mode for a current block of video data; and The current block of video data is encoded using the current intra-frame prediction mode to generate an encoded block of video data. The apparatus of claim 25, wherein the one or more processors are also configured to: encode an index to the primary most probable mode list or the secondary most probable mode list, wherein the index indicates the primary most probable mode A non-planar intra-frame prediction mode in the list or the LLM list. The apparatus of claim 26, wherein in order to encode the index of the primary most probable mode list or the secondary most probable mode list, the one or more processors are also configured to: determining a context for entropy encoding a first bin of the index based on a coding tool for the current block of video data; and The first bin of the index is entropy encoded using the context. The apparatus of claim 27, wherein the coding tool is one of a normal intra-frame prediction mode, an intra-frame sub-partition mode, or a multiple auxiliary line mode. The apparatus of claim 25, wherein N is 22 and Np is 6. The apparatus of claim 25, wherein to construct the general most probable mode list, the one or more processors are also configured to: adding corresponding intra-frame prediction modes from corresponding neighboring blocks of the current block of video data to the general most probable mode list; and A plurality of intra-frame prediction modes offset from the corresponding intra-frame prediction modes from the corresponding neighboring blocks are added to the general most probable mode list. The apparatus of claim 25, wherein in order to add the corresponding intra-frame prediction modes from the corresponding neighboring blocks of the current block of video data to the general most probable mode list, the one or more a processor is also configured to: based on the corresponding intra-frame prediction modes are available and have not been added to the general most probable mode list, the corresponding neighbors from the current video data block The corresponding intra-frame prediction modes of the block are added to the list of general most probable modes. An apparatus according to claim 25, further comprising: a camera configured to capture a picture including the current video data block.

Images