Video decoding method, video encoding method, device, computer equipment and storage medium

Abstract

Embodiments of the present application provide a method, apparatus, computer equipment and storage medium for video decoding. In the method, encoded information of a current block and adjacent blocks of the current block in a current picture is received from an encoded video code stream. A merge candidate list of the current block is generated based on the adjacent blocks of the current block. The merge candidate list of the current block is divided into a plurality of subgroups. Each of the plurality of subgroups includes one or more merge candidates. One or more merge candidates are sorted in each subgroup by a corresponding template matching (TM) cost associated with each of the one or more merge candidates. The current block is reconstructed based on the merge candidate selected from the merge candidate list of the current block.

Description

[0001] Cross-references

[0002] This application claims priority to U.S. Patent Application No. 17 / 945,006, “GROUPING BASED ADAPTIVE REORDERING OF MERGE CANDIDATE,” filed on September 14, 2022, which claims priority to U.S. Provisional Application No. 63 / 252,602, “Grouping Based Adaptive Reordering of Merge Candidate,” filed on October 5, 2021. The disclosures of the prior applications are incorporated herein by reference in their entirety. Technical Field

[0003] This disclosure describes embodiments generally related to video coding. Background Art

[0004] The background description provided herein is intended to present the background of the present application as a whole. The extent to which the work of the presently named inventors described in the background section and various aspects of this specification is performed does not indicate that it is prior art at the time of filing this application, and it is never explicitly or implicitly admitted that it is prior art for this application.

[0005] An uncompressed digital image and / or video may include a series of pictures, each picture having a spatial dimension of, for example, 1920×1080 luma samples and associated chroma samples. The series of pictures has a fixed or variable picture rate (also informally referred to as a frame rate), for example, 60 pictures per second or 60 Hz. Uncompressed images and / or videos have specific bit rate requirements. For example, 1080p60 4:2:0 video (1920x1080 luma sample resolution, 60 Hz frame rate) with 8 bits per sample requires close to 1.5 Gbit / s of bandwidth. One hour of such video would require over 600 GB of storage space.

[0006] One purpose of image and / or video encoding and decoding is to reduce the redundant information of input image and / or video signal by compression. Video compression can help reduce the requirements of the above-mentioned bandwidth and / or storage space, and in some cases can reduce it by two or more orders of magnitude. Although the description herein uses video encoding / decoding as an illustrative example, the same technology can be applied to image encoding / decoding in a similar manner without departing from the spirit of the present disclosure. Lossless and lossy compression, as well as a combination of the two, can be adopted. Lossless compression refers to the technology of reconstructing an exact copy of the original signal from the compressed original signal. When lossy compression is used, the reconstructed signal may not be exactly the same as the original signal, but the distortion between the original signal and the reconstructed signal is small enough so that the reconstructed signal can be used for the intended application. Lossy compression is widely used in video. The amount of distortion allowed depends on the application. For example, users of some consumer streaming applications can tolerate higher distortion than users of TV applications. The achievable compression ratio reflects that higher allowed / tolerable distortion can produce higher compression ratios.

[0007] Video encoders and decoders may utilize techniques from several broad categories including, for example, motion compensation, transform processing, quantization, and entropy coding and decoding.

[0008] Video codec techniques may include techniques known as intra-frame coding. In intra-frame coding, sample values ​​are represented without reference to samples or other data from previously reconstructed reference pictures. In some video codecs, pictures are spatially subdivided into blocks of samples. When all sample blocks are encoded in intra-frame mode, the picture may be an intra-frame picture. Intra-frame pictures and their derivatives (such as independent decoder refresh pictures) can be used to reset the decoder state, and can therefore be used as the first picture in an encoded video stream and video session, or as a still image. Samples of intra-frame blocks can be exposed to transformation, and transform coefficients can be quantized before entropy coding and decoding. Intra-frame prediction can be a technique for minimizing sample values ​​in the pre-transform domain. In some cases, the smaller the DC value after transformation, and the smaller the AC coefficient, the fewer bits are required to represent the entropy coded block at a given quantization step size.

[0009] Traditional intra-frame codecs, such as those used in MPEG-2 generation codecs, do not use intra-frame prediction. However, some newer video compression techniques include techniques that attempt to make predictions based on, for example, surrounding sample data and / or metadata that is obtained during encoding / decoding of a block of data. Such techniques are hereinafter referred to as "intra-frame prediction" techniques. Note that, in at least some cases, intra-frame prediction uses only reference data from the current picture being reconstructed, and not reference data from reference pictures.

[0010] There can be many different forms of intra-frame prediction. When more than one such technique can be used in a given video codec technique, the technique used can be encoded in the intra-frame prediction mode. In some cases, the intra-frame prediction mode can have sub-modes and / or parameters, where these sub-modes and / or parameters can be encoded separately or included in the mode codeword, which defines the prediction mode used. For a given mode, the sub-mode and / or parameter combination to use the codeword may have an impact on the coding efficiency gain through intra-frame prediction, and the same is true for the entropy coding and decoding technique that converts the codeword into the codestream.

[0011] Some mode of intra prediction was introduced with H.264, improved in H.265, and further improved in newer codecs such as joint exploration model (JEM), versatile video coding (VVC), and benchmark set (BMS). The predictor block can be formed using the values ​​of neighboring samples of samples that are already available. The sample values ​​of neighboring samples are copied into the predictor block according to the direction. The reference to the direction in use can be encoded in the bitstream, or it can be predicted itself.

[0012] Reference Figure 1A , a subset of nine known prediction directions from the 33 possible prediction directions defined in H.265 (corresponding to the 33 angular modes of the 35 intra modes) is depicted in the lower right. The point (101) where the arrows converge represents the sample being predicted. The arrows represent the direction in which the sample is being predicted. For example, arrow (102) indicates that sample (101) is predicted based on one or more samples at an angle of 45 degrees to the horizontal direction at the upper right. Similarly, arrow (103) indicates that sample (101) is predicted based on one or more samples at an angle of 22.5 degrees to the horizontal direction at the lower left.

[0013] Still reference Figure 1A, a square block (104) including 4×4 samples is shown in the upper left (indicated by the thick dashed line). The square block (104) includes 16 samples, each of which is labeled with "S" and its position in the Y dimension (e.g., row index) and its position in the X dimension (e.g., column index). For example, sample S21 is the second sample in the Y dimension (starting from the top) and the first sample in the X dimension (starting from the left). Similarly, sample S44 is the fourth sample in the block (104) in both the X dimension and the Y dimension. Since the block is a 4×4 size sample, S44 is located in the lower right corner. Reference samples following a similar numbering scheme are also shown. Reference samples are labeled with "R" and their Y position (e.g., row index) and X position (e.g., column index) relative to the block (104). In H.264 and H.265, the prediction samples are adjacent to the block being reconstructed, so there is no need to use negative values.

[0014] Intra-picture prediction can be performed by copying reference sample values ​​from neighboring samples indicated by a signaled prediction direction. For example, assume that the encoded video bitstream includes signaling that indicates, for this block, a prediction direction consistent with arrow (102), i.e., predicting samples based on a prediction sample to the upper right at a 45 degree angle to the horizontal. In this case, samples S41, S32, S23, and S14 are predicted based on the same reference sample R05. Sample S44 is predicted based on reference sample R08.

[0015] In some cases, for example by interpolation, the values ​​of multiple reference samples may be combined in order to calculate the reference sample, particularly when the direction is not divisible by 45 degrees.

[0016] As video coding techniques have evolved, the number of possible directions has increased. In H.264 (2003), nine different directions could be represented. This increased to 33 in H.265 (2013). Currently, JEM / VVC / BMS can support up to 65 directions. Experiments have been done to identify the most likely directions, and certain techniques in entropy coding are used to represent those possible directions using a small number of bits, accepting some penalty for less likely directions. Additionally, the direction itself can sometimes be predicted based on neighboring directions used in adjacent, already decoded blocks.

[0017] Figure 1B A schematic diagram (110) depicting 65 intra prediction directions according to JEM is shown to illustrate the increasing number of prediction directions over time.

[0018] The mapping of the intra-frame prediction direction bits representing the direction in the coded video bitstream can vary depending on the video coding technology. The mapping can range from a simple direct mapping to codewords to complex adaptive schemes involving the most likely mode and similar techniques. However, in most cases, there may be certain directions in the video content that are statistically less likely to appear than certain other directions. Since the goal of video compression is to reduce redundancy, in a well-working video codec, those unlikely directions will be represented by a larger number of bits than more likely directions.

[0019] Inter prediction with motion compensation may be used for image and / or video encoding and decoding. Motion compensation may be a lossy compression technique and may involve a technique where a block of sample data from a previously reconstructed picture or part of a reconstructed picture (reference picture) is used for prediction of a newly reconstructed picture or part of a picture after being spatially shifted in a direction indicated by a motion vector (hereinafter MV). In some cases, the reference picture may be the same as the picture currently being reconstructed. The MV may have two dimensions, X and Y, or three dimensions, where the third dimension indicates the reference picture in use (the latter may indirectly be a temporal dimension).

[0020] In some video compression techniques, the MV applied to a region of sample data can be predicted based on other MVs, such as those MVs associated with another region of sample data that is spatially adjacent to the region being reconstructed and that precede the MV in decoding order. Doing so can greatly reduce the amount of data required to encode the MV, thereby eliminating redundant information and increasing the amount of compression. MV prediction can be done effectively, for example, when encoding an input video signal derived from a camera (called natural video), there is a statistical probability that regions larger than the region to which a single MV applies will move in a similar direction, so in some cases, similar motion vectors derived from MVs of neighboring regions can be used for prediction. This results in the MV found for a given region being similar or identical to the MV predicted from the surrounding MVs, and after entropy coding, it can be represented with fewer bits than the number of bits used when the MV is directly encoded. In some cases, MV prediction can be an example of lossless compression of a signal (i.e., MV) derived from the original signal (i.e., sample stream). In other cases, MV prediction itself may be lossy, for example due to rounding errors when calculating predicted values ​​based on several surrounding MVs.

[0021] H.265 / HEVC (ITU-T Rec. H.265, "High Efficiency Video Coding", December 2016) describes various MV prediction mechanisms. Among the various MV prediction mechanisms provided by H.265, a technique referred to below as "spatial merging" is described in conjunction with FIG. 2 .

[0022] Referring to Figure 2, the current block (201) includes samples found by the encoder during motion search, which can be predicted based on the previous block that has been spatially moved by the same size. The MV is not encoded directly, but is derived from metadata associated with one or more reference pictures, such as the most recent (in decoding order) reference picture, by using the MV associated with any of the five surrounding samples. The five surrounding samples are represented by A0, A1 and B0, B1, B2 (from 202 to 206). In H.265, MV prediction can use the prediction value of the same reference picture being used by the neighboring blocks. Summary of the invention

[0023] Various aspects of the embodiments of the present application provide methods and apparatus for video encoding / decoding. In some examples, the apparatus for decoding a video includes a processing circuit.

[0024] According to one aspect of the present disclosure, a video decoding method performed in a video decoder is provided. In the method, encoded information of a current block in a current picture and neighboring blocks of the current block are received from an encoded video code stream; a merge candidate list of the current block is generated according to the neighboring blocks of the current block; the merge candidate list of the current block is divided into a plurality of subgroups, each of the plurality of subgroups includes one or more merge candidates, wherein the one or more merge candidates are sorted in each subgroup by a corresponding template matching TM cost associated with each of the one or more merge candidates; and the current block is reconstructed according to the merge candidate selected from the merge candidate list of the current block.

[0025] In the method, the plurality of subgroups in the merge candidate list are reordered according to a corresponding TM cost value associated with each of the plurality of subgroups.

[0026] In order to reorder multiple subgroups in a merge candidate list, the corresponding TM cost value associated with each of the multiple subgroups is first determined; and the multiple subgroups in the merge candidate list are reordered according to the ascending order of the TM cost values ​​associated with the multiple subgroups, so that the first subgroup of the multiple subgroups in the reordered merge candidate list is associated with the minimum TM cost value among the TM cost values.

[0027] In order to determine a corresponding TM cost associated with each of the multiple subgroups, multiple template matching TM cost values ​​of the one or more merge candidates in a first subgroup of the multiple subgroups are determined, each of the template matching TM cost values ​​being associated with a difference between an adjacent neighboring sample of the current block and an adjacent neighboring sample of a corresponding merge candidate in the first subgroup; and the one or more merge candidates in the first subgroup of the multiple subgroups are reordered according to an ascending order of the multiple TM cost values ​​of the one or more merge candidates in the first subgroup, so that a first merge candidate in the reordered first subgroup has a minimum TM cost value.

[0028] In one example, the TM cost value associated with the first subgroup of the plurality of subgroups is determined as the minimum TM cost value among the plurality of TM cost values ​​of the one or more merge candidates in the first subgroup.

[0029] In one example, the TM cost value associated with the first subgroup of the plurality of subgroups is determined as a median TM cost value of the plurality of TM cost values ​​of the one or more merge candidates in the first subgroup.

[0030] In one example, the TM cost value associated with the first subgroup of the plurality of subgroups is determined as a median TM cost value of a plurality of minimum TM cost values ​​among the plurality of TM cost values ​​of the one or more merge candidates in the first subgroup.

[0031] In one example, the TM cost value associated with the first subgroup of the plurality of subgroups is determined as an average of first two smallest TM cost values ​​of the plurality of TM cost values ​​of the one or more merge candidates in the first subgroup.

[0032] In the method, the merge candidate list of the current block is generated based on at least one of the following: spatial motion vector MV prediction values ​​of spatial neighboring blocks of the neighboring blocks of the current block; temporal MV prediction values ​​of co-located blocks of the current block; history-based MV prediction values ​​from a first-in-first-out FIFO table; pairwise average MV prediction values; zero MV; non-adjacent MV prediction values ​​of non-adjacent spatial neighboring blocks of the neighboring blocks of the current block; or non-adjacent temporal MV prediction values ​​of the current block.

[0033] Based on the merge candidate list including the non-adjacent MV prediction values ​​and the non-adjacent time MV prediction values, the merge candidate list is divided into a first subgroup including a first group of the non-adjacent MV prediction values, and the first group of the non-adjacent MV prediction values ​​are positioned along the angle of π / 4, the angle of π / 2, the angle of 3π / 4, the angle of π, and the angle of 5π / 4 relative to the horizontal axis; and the merge candidate list is divided into a second subgroup including a second group of the non-adjacent MV prediction values, and the second group of the non-adjacent MV prediction values ​​are positioned along the angle of π / 4, the angle of 3π / 8, the angle of π / 2, the angle of 5π / 8, the angle of 3π / 4, the angle of 7π / 8, the angle of π, the angle of 9π / 8, and the angle of 5π / 4 relative to the horizontal axis.

[0034] The merge candidate list is divided into a third subset including the non-contiguous temporal MV prediction values.

[0035] In some examples, the merge candidate list is divided into the plurality of sub-groups such that each of the plurality of sub-groups includes one of the same number of merge candidates, a predefined number of merge candidates, or the same type of merge candidates.

[0036] According to another aspect of the present disclosure, a device is provided, wherein the device comprises a processing circuit, and the processing circuit is used to execute any of the video encoding / decoding methods.

[0037] Aspects of the present disclosure provide a non-volatile computer-readable storage medium storing instructions. When the instructions are executed by a computer used for video decoding, the computer performs any of the video encoding / decoding methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Other features, properties and various advantages of the disclosed subject matter will become more apparent from the following detailed description and accompanying drawings, in which:

[0039] Figure 1A is a schematic diagram of an exemplary subset of intra prediction modes.

[0040] Figure 1B A diagram of exemplary intra prediction directions.

[0041] FIG2 is a schematic diagram of an exemplary current block and its surrounding spatial merging candidates.

[0042] Figure 3 is a schematic diagram of a simplified block diagram of a communication system (300) according to an embodiment.

[0043] Figure 4 is a schematic diagram of a simplified block diagram of a communication system (400) according to an embodiment.

[0044] Figure 5 is a schematic diagram of a simplified block diagram of a decoder according to an embodiment.

[0045] Figure 6 is a schematic diagram of a simplified block diagram of an encoder according to an embodiment.

[0046] Figure 7 A block diagram of an encoder according to another embodiment is shown.

[0047] Figure 8 A block diagram of a decoder according to another embodiment is shown.

[0048] Fig. 9 Exemplary positions of spatial merging candidates in another embodiment are shown.

[0049] Fig.10 An exemplary redundancy check of spatial merging candidates is shown.

[0050] Fig.11 A schematic diagram showing motion vector scaling for temporal merging candidates according to an embodiment is shown.

[0051] Fig.12 Exemplary candidate positions of temporal merging candidates according to an embodiment are shown.

[0052] Fig.13 An exemplary template matching procedure according to an embodiment is shown.

[0053] Fig.14 An exemplary pattern of non-adjacent spatial merging candidates according to an embodiment is shown.

[0054] Fig.15 An exemplary derivation of sub-block based merge candidates according to an embodiment is shown.

[0055] Fig.16 An exemplary pattern of non-adjacent spatial merging candidates according to an embodiment is shown.

[0056] Fig.17 A flow chart outlining an exemplary decoding process according to some embodiments of the present disclosure is shown.

[0057] Fig.18 A flow chart outlining an exemplary encoding process according to some embodiments of the present disclosure is shown.

[0058] Fig.19 is a schematic diagram of a computer device according to an embodiment. DETAILED DESCRIPTION

[0059] Figure 33 is an exemplary simplified block diagram of a communication system (300). The communication system (300) includes a plurality of terminal devices that can communicate with each other via, for example, a network (350). For example, the communication system (300) includes a first pair of terminal devices (310) and a terminal device (320) interconnected via the network (350). Figure 3 In an embodiment, the terminal device (310) and the terminal device (320) perform unidirectional data transmission. For example, the terminal device (310) may encode video data (e.g., a video picture stream collected by the terminal device (310)) for transmission to another terminal device (320) via the network (350). The encoded video data is transmitted in the form of one or more encoded video code streams. The terminal device (320) may receive the encoded video data from the network (350), decode the encoded video data to restore the video data, and display the video picture based on the restored video data. Unidirectional data transmission is more common in applications such as media services.

[0060] In another embodiment, the communication system (300) includes a second pair of terminal devices (330) and (340) that perform bidirectional transmission of encoded video data, such as during a video conference. For bidirectional data transmission, each of the terminal devices (330) and (340) can encode video data (such as a video picture stream collected by the terminal device) for transmission to the other of the terminal devices (330) and (340) via a network (350). Each of the terminal devices (330) and (340) can also receive the encoded video data transmitted by the other of the terminal devices (330) and (340), and can decode the encoded video data to restore the video data, and can display the video picture on an accessible display device based on the restored video data.

[0061] exist Figure 3In the embodiment of the present invention, the terminal device (310), the terminal device (320), the terminal device (330) and the terminal device (340) may be a server, a personal computer and a smart phone, respectively, but the principles disclosed in the present application may not be limited thereto. The embodiments disclosed in the present application are applicable to laptop computers, tablet computers, media players and / or dedicated video conferencing equipment. The network (350) represents any number of networks that transmit encoded video data between the terminal devices (310), the terminal devices (320), the terminal devices (330) and the terminal devices (340), including, for example, wired (wired) and / or wireless communication networks. The communication network (350) may exchange data in circuit switching and / or packet switching channels. The network may include a telecommunications network, a local area network, a wide area network and / or the Internet. For the purpose of this discussion, unless explained below, the architecture and topology of the network (350) may be irrelevant to the operation disclosed in the present application.

[0062] As an example, Figure 4 The video encoder and video decoder in a streaming environment are shown. The subject matter disclosed in this application is equally applicable to other video-enabled applications including, for example, video conferencing, digital TV, streaming servers, and storing compressed video on digital media including CDs, DVDs, memory sticks, etc.

[0063] The streaming system may include an acquisition subsystem (413), which may include a video source (401) such as a digital camera, which creates an uncompressed video picture stream (402). In an embodiment, the video picture stream (402) includes samples taken by a digital camera. Compared to the encoded video data (404) (or the encoded video bitstream), the video picture stream (402) is depicted as a thick line to emphasize the high data volume of the video picture stream, and the video picture stream (402) can be processed by an electronic device (420), which includes a video encoder (403) coupled to the video source (401). The video encoder (403) may include hardware, software, or a combination of hardware and software to implement or implement various aspects of the disclosed subject matter as described in more detail below. Compared to the video picture stream (402), the encoded video data (404) (or the encoded video bitstream (404)) is depicted as a thin line to emphasize the lower amount of data of the encoded video data (404) (or the encoded video bitstream (404)), which can be stored on the streaming server (405) for future use. One or more streaming client subsystems, such as Figure 4The client subsystem (406) and the client subsystem (408) in the streaming server (405) can access the streaming server (405) to retrieve the copy (407) and the copy (409) of the encoded video data (404). The client subsystem (406) may include, for example, a video decoder (410) in the electronic device (430). The video decoder (410) decodes the incoming copy (407) of the encoded video data and generates an output video picture stream (411) that can be presented on a display (412) (e.g., a display screen) or another presentation device (not depicted). In some streaming systems, the encoded video data (404), the video data (407), and the video data (409) (e.g., a video bitstream) can be encoded according to certain video encoding / compression standards. Examples of these standards include ITU-T H.265. In an embodiment, the video coding standard under development is informally referred to as Versatile Video Coding (VVC), and the present application can be used in the context of the VVC standard.

[0064] It should be noted that the electronic device (420) and the electronic device (430) may include other components (not shown). For example, the electronic device (420) may include a video decoder (not shown), and the electronic device (430) may also include a video encoder (not shown).

[0065] Figure 5 is an exemplary block diagram of a video decoder (510). The video decoder (510) may be provided in an electronic device (530). The electronic device (530) may include a receiver (531) (eg, a receiving circuit). The video decoder (510) may be used to replace Figure 4 A video decoder (410) of an embodiment.

[0066] The receiver (531) may receive one or more encoded video sequences to be decoded by the video decoder (510). In one embodiment, the encoded video sequences are received one at a time, wherein the decoding of each encoded video sequence is independent of the decoding of other encoded video sequences. The encoded video sequence may be received from a channel (501), which may be a hardware / software link to a storage device storing the encoded video data. The receiver (531) may receive the encoded video data as well as other data, such as encoded audio data and / or auxiliary data streams that may be forwarded to their respective consuming entities (not shown). The receiver (531) may separate the encoded video sequence from the other data. To prevent network jitter, a buffer memory (515) may be coupled between the receiver (531) and the entropy decoder / parser (520) (hereinafter referred to as "parser (520)"). In some applications, the buffer memory (515) is part of the video decoder (510). In other cases, the buffer memory (515) may be provided external to the video decoder (510) (not shown). In other cases, a buffer memory (not shown) is provided outside the video decoder (510) to prevent network jitter, for example, and another buffer memory (515) may be configured inside the video decoder (510) to handle broadcast timing, for example. When the receiver (531) receives data from a storage / forward device with sufficient bandwidth and controllability or from an isochronous network, it may not be necessary to configure the buffer memory (515), or the buffer memory may be made smaller. Of course, in order to use on a service packet network such as the Internet, a buffer memory (515) may also be required, and the buffer memory may be relatively large and have an adaptive size, and may be at least partially implemented in an operating system or a similar element (not shown) outside the video decoder (510).

[0067] The video decoder (510) may include a parser (520) to reconstruct symbols (521) from the encoded video sequence. The types of symbols include information used to manage the operation of the video decoder (510) and potential information used to control a display device such as a display device (512) (e.g., a display screen) that is not part of the electronic device (530) but can be coupled to the electronic device (530), such as Figure 5As shown in . The control information for the display device may be a parameter set fragment (not indicated) of Supplemental Enhancement Information (SEI message) or Video Usability Information (VUI). The parser (520) may parse / entropy decode the received coded video sequence. The encoding of the coded video sequence may be performed according to a video coding technique or standard, and may follow various principles, including variable length coding, Huffman coding, arithmetic coding with or without context sensitivity, and the like. The parser (520) may extract a subgroup parameter set of at least one subgroup of the subgroups of pixels in the video decoder from the coded video sequence based on at least one parameter corresponding to the group. The subgroup may include a Group of Pictures (GOP), a picture, a tile, a slice, a macroblock, a Coding Unit (CU), a block, a Transform Unit (TU), a Prediction Unit (PU), and the like. The parser (520) may also extract information from the encoded video sequence, such as transform coefficients, quantizer parameter values, motion vectors, and so on.

[0068] The parser (520) may perform entropy decoding / parsing operations on the video sequence received from the buffer memory (515), thereby creating symbols (521).

[0069] Depending on the type of coded video picture or portion of coded video picture (e.g., inter- and intra-pictures, inter- and intra-blocks) and other factors, the reconstruction of the symbol (521) may involve multiple different units. Which units are involved and how they are involved may be controlled by subgroup control information parsed by the parser (520) from the coded video sequence. For the sake of brevity, such subgroup control information flow between the parser (520) and the multiple units below is not described.

[0070] In addition to the functional blocks already mentioned, the video decoder (510) can be conceptually subdivided into several functional units as described below. In a practical embodiment operating under commercial constraints, many of these units interact closely with each other and can be integrated with each other. However, for the purpose of describing the disclosed subject matter, the conceptual subdivision into the following functional units is appropriate.

[0071] The first unit is a sealer / inverse transform unit (551). The sealer / inverse transform unit (551) receives quantized transform coefficients as symbols (521) from the parser (520) and control information, including which transform method to use, block size, quantization factor, quantization scaling matrix, etc. The sealer / inverse transform unit (551) can output a block including sample values, which can be input into an aggregator (555).

[0072] In some cases, the output samples of the scaler / inverse transform unit (551) may belong to an intra-coded block. An intra-coded block is a block that does not use predictive information from a previously reconstructed picture, but may use predictive information from a previously reconstructed portion of the current picture. Such predictive information may be provided by an intra-picture prediction unit (552). In some cases, the intra-picture prediction unit (552) uses reconstructed information extracted from the current picture buffer (558) to generate surrounding blocks of the same size and shape as the block being reconstructed. For example, the current picture buffer (558) buffers a partially reconstructed current picture and / or a fully reconstructed current picture. In some cases, the aggregator (555) adds the prediction information generated by the intra-prediction unit (552) to the output sample information provided by the scaler / inverse transform unit (551) on a per-sample basis.

[0073] In other cases, the output samples of the scaler / inverse transform unit (551) may belong to an inter-frame coded and potentially motion compensated block. In this case, the motion compensated prediction unit (553) may access the reference picture memory (557) to extract samples for prediction. After the extracted samples are motion compensated according to the symbols (521), these samples may be added to the output of the scaler / inverse transform unit (551) (in this case referred to as residual samples or residual signals) by the aggregator (555) to generate output sample information. The acquisition of the predicted samples by the motion compensated prediction unit (553) from the address in the reference picture memory (557) may be controlled by a motion vector, and the motion vector is provided to the motion compensated prediction unit (553) in the form of the symbols (521), for example, including X, Y and reference picture components. Motion compensation may also include interpolation of sample values ​​extracted from the reference picture memory (557) when using sub-sample accurate motion vectors, motion vector prediction mechanisms, and the like.

[0074] The output samples of the aggregator (555) may be employed by various loop filtering techniques in a loop filter unit (556). The video compression techniques may include in-loop filter techniques controlled by parameters included in the coded video sequence (also referred to as the coded video bitstream) and available to the loop filter unit (556) as symbols (521) from the parser (520). The video compression techniques may also be responsive to meta-information obtained during decoding of a coded picture or a previous (in decoding order) portion of the coded video sequence, and to previously reconstructed and loop filtered sample values.

[0075] The output of the loop filter unit (556) may be a sample stream that may be output to a display device (512) and stored in a reference picture memory (557) for subsequent inter-picture prediction.

[0076] Once fully reconstructed, certain coded pictures may be used as reference pictures for future prediction. For example, once the coded picture corresponding to the current picture is fully reconstructed, and the coded picture is identified as a reference picture (e.g., by the parser (520)), the current picture buffer (558) may become part of the reference picture memory (557), and a new current picture buffer may be reallocated before starting to reconstruct a subsequent coded picture.

[0077] The video decoder (510) may perform decoding operations according to a predetermined video compression technique, such as in the ITU-T H.265 standard. The encoded video sequence may conform to the syntax specified by the video compression technique or standard used in the sense that the encoded video sequence follows the syntax of the video compression technique or standard and the profile recorded in the video compression technique or standard. Specifically, the profile may select certain tools from all the tools available in the video compression technique or standard as the only tools available for use under the profile. For compliance, the complexity of the encoded video sequence is also required to be within the range defined by the hierarchy of the video compression technique or standard. In some cases, the hierarchy limits the maximum picture size, the maximum frame rate, the maximum reconstruction sampling rate (measured in, for example, mega samples per second), the maximum reference picture size, etc. In some cases, the limits set by the hierarchy may be further limited by the Hypothetical Reference Decoder (HRD) specification and the metadata of the HRD buffer management signaled in the encoded video sequence.

[0078] In an embodiment, the receiver (531) may receive additional (redundant) data along with the encoded video. The additional data may be part of the encoded video sequence. The additional data may be used by the video decoder (510) to properly decode the data and / or more accurately reconstruct the original video data. The additional data may be in the form of, for example, temporal, spatial or signal-to-noise ratio (SNR) enhancement layers, redundant slices, redundant pictures, forward error correction codes, etc.

[0079] Figure 6 603 is an exemplary block diagram of a video encoder (603). The video encoder (603) is disposed in an electronic device (620). The electronic device (620) includes a transmitter (640) (eg, a transmission circuit). The video encoder (603) may be used to replace Figure 4 A video encoder (403) in an embodiment.

[0080] The video encoder (603) can be used to obtain the video source (601) (not Figure 6 In another embodiment, the video source (601) is a part of the electronic device (620) to receive video samples, and the video source can collect video images to be encoded by the video encoder (603). In another embodiment, the video source (601) is a part of the electronic device (620).

[0081] The video source (601) may provide a source video sequence in the form of a digital video sample stream to be encoded by the video encoder (603), wherein the digital video sample stream may have any suitable bit depth (e.g., 8-bit, 10-bit, 12-bit, ...), any color space (e.g., BT.601 Y CrCB, RGB, ...), and any suitable sampling structure (e.g., Y CrCb 4:2:0, Y CrCb 4:4:4). In a media service system, the video source (601) may be a storage device storing previously prepared videos. In a video conferencing system, the video source (601) may be a camera that captures local image information as a video sequence. The video data may be provided as a plurality of separate pictures that are given motion when viewed sequentially. The pictures themselves may be constructed as a spatial pixel array, wherein each pixel may include one or more samples depending on the sampling structure, color space, etc. used. The relationship between pixels and samples may be easily understood by those skilled in the art. The following description focuses on samples.

[0082] According to an embodiment, the video encoder (603) may encode and compress pictures of a source video sequence into an encoded video sequence (643) in real time or under any other time constraints required by the application. Implementing an appropriate encoding speed is a function of the controller (650). In some embodiments, the controller (650) controls other functional units as described below and is functionally coupled to these units. For the sake of simplicity, coupling is not indicated in the figure. The parameters set by the controller (650) may include rate control related parameters (picture skipping, quantizer, lambda value of rate distortion optimization technology, etc.), picture size, group of pictures (GOP) layout, maximum motion vector search range, etc. The controller (650) can be used to have other suitable functions that are related to the video encoder (603) optimized for a certain system design.

[0083] In some embodiments, the video encoder (603) operates in a coding loop. As a simple description, in embodiments, the coding loop may include a source encoder (630) (e.g., responsible for creating symbols, such as a symbol stream, based on an input picture to be encoded and a reference picture) and a (local) decoder (633) embedded in the video encoder (603). The decoder (633) reconstructs the symbols to create sample data in a manner similar to how the (remote) decoder creates sample data. The reconstructed sample stream (sample data) is input to a reference picture memory (634). Since the decoding of the symbol stream produces bit-accurate results that are independent of the decoder location (local or remote), the contents of the reference picture memory (634) are also bit-accurate between the local encoder and the remote encoder. In other words, the reference picture samples "seen" by the prediction part of the encoder are exactly the same as the sample values ​​that the decoder will "see" when using the prediction during decoding. This basic principle of reference picture synchronization (and the drift that occurs when synchronization cannot be maintained, such as due to channel errors) is also used in some related technologies.

[0084] The operation of the "local" decoder (633) can be combined with the above Figure 4 The "remote" decoder described in detail for the video decoder (510) is identical. However, additional brief reference is made to Figure 5 , when symbols are available and the entropy encoder (645) and parser (520) are capable of losslessly encoding / decoding the symbols into an encoded video sequence, the entropy decoding portion of the video decoder (510), including the buffer memory (515) and the parser (520), may not be fully implemented in the local decoder (633).

[0085] In some instances, in addition to the parsing / entropy decoding present in the decoder, the decoder technology is present in the corresponding encoder in the same or substantially the same functional form. Accordingly, the application focuses on the decoder operation. The description of the encoder technology can be simplified because the encoder technology is mutually inverse to the decoder technology described comprehensively. A more detailed description is only needed in certain areas and is provided below.

[0086] During operation, in some embodiments, the source encoder (630) may perform motion compensated predictive coding. The motion compensated predictive coding predictively encodes an input picture with reference to one or more previously encoded pictures from a video sequence designated as "reference pictures." In this manner, the encoding engine (632) encodes the differences between pixel blocks of the input picture and pixel blocks of a reference picture that may be selected as a prediction reference for the input picture.

[0087] The local video decoder (633) may decode the encoded video data of the picture that may be designated as the reference picture based on the symbol created by the source encoder (630). The operation of the encoding engine (632) may be a lossy process. When the encoded video data is available at the video decoder ( Figure 6 When the video sequence is decoded at a remote location (not shown), the reconstructed video sequence may typically be a copy of the source video sequence with some errors. The local video decoder (633) replicates the decoding process that may be performed by the video decoder on the reference picture and may cause the reconstructed reference picture to be stored in the reference picture cache (634). In this way, the video encoder (603) may store a copy of the reconstructed reference picture locally that has common content (absent transmission errors) with the reconstructed reference picture to be obtained by the remote video decoder.

[0088] The predictor (635) may perform a prediction search for the encoding engine (632). That is, for a new picture to be encoded, the predictor (635) may search the reference picture memory (634) for sample data (as candidate reference pixel blocks) or certain metadata, such as reference picture motion vectors, block shapes, etc., that may serve as appropriate prediction references for the new picture. The predictor (635) may operate pixel-by-pixel based on sample blocks to find a suitable prediction reference. In some cases, based on the search results obtained by the predictor (635), it may be determined that the input picture may have prediction references taken from a plurality of reference pictures stored in the reference picture memory (634).

[0089] The controller (650) may manage encoding operations of the source encoder (630), including, for example, setting parameters and subgroup parameters for encoding video data.

[0090] The outputs of all the above functional units may be entropy encoded in an entropy encoder (645). The entropy encoder (645) performs lossless compression on the symbols generated by the various functional units according to techniques such as Huffman coding, variable length coding, arithmetic coding, etc., thereby converting the symbols into a coded video sequence.

[0091] The transmitter (640) may buffer the encoded video sequence created by the entropy encoder (645) in preparation for transmission over a communication channel (660), which may be a hardware / software link to a storage device where the encoded video data will be stored. The transmitter (640) may combine the encoded video data from the video encoder (603) with other data to be transmitted, such as encoded audio data and / or ancillary data streams (source not shown).

[0092] The controller (650) may manage the operation of the video encoder (603). During encoding, the controller (650) may assign a certain coded picture type to each coded picture, but this may affect the coding techniques that can be applied to the corresponding picture. For example, a picture may generally be assigned to any of the following picture types:

[0093] An intra picture (I picture) may be a picture that can be encoded and decoded without using any other picture in the sequence as a prediction source. Some video codecs allow different types of intra pictures, including, for example, Independent Decoder Refresh ("IDR") pictures. Those skilled in the art are aware of the variations of I pictures and their corresponding applications and features.

[0094] A predictive picture (P picture) may be a picture that can be encoded and decoded using intra prediction or inter prediction, which uses at most one motion vector and a reference index to predict sample values ​​for each block.

[0095] Bidirectional predictive pictures (B pictures), which can be pictures that can be encoded and decoded using intra prediction or inter prediction, which uses up to two motion vectors and reference indices to predict the sample values ​​of each block. Similarly, multiple predictive pictures can use more than two reference pictures and associated metadata for reconstruction of a single block.

[0096] The source picture may typically be spatially subdivided into blocks of samples (e.g., blocks of 4×4, 8×8, 4×8, or 16×16 samples), and coded block by block. These blocks may be predictively coded with reference to other (already coded) blocks, which are determined according to the coding allocation applied to the block's corresponding picture. For example, blocks of an I picture may be non-predictively coded, or the blocks may be predictively coded (spatial prediction or intra prediction) with reference to already coded blocks of the same picture. Blocks of pixels of a P picture may be predictively coded by spatial prediction with reference to one previously coded reference picture or by temporal prediction. Blocks of a B picture may be predictively coded by spatial prediction with reference to one or two previously coded reference pictures or by temporal prediction.

[0097] The video encoder (603) may perform encoding operations according to a predetermined video encoding technique or standard, such as ITU-T H.265 Recommendation. In operation, the video encoder (603) may perform various compression operations, including predictive encoding operations that exploit temporal and spatial redundancy in an input video sequence. Thus, the encoded video data may conform to the syntax specified by the video encoding technique or standard used.

[0098] In an embodiment, the transmitter (640) may transmit additional data when transmitting the encoded video. The source encoder (630) may include such data as part of the encoded video sequence. The additional data may include other forms of redundant data such as temporal / spatial / SNR enhancement layers, redundant pictures and slices, SEI messages, VUI parameter set fragments, etc.

[0099] The captured video may be taken as a plurality of source pictures (video pictures) in a temporal sequence. Intra-picture prediction (often simplified to intra-prediction) exploits spatial correlations in a given picture, while inter-picture prediction exploits (temporal or other) correlations between pictures. In an embodiment, a particular picture being encoded / decoded is divided into blocks, and the particular picture being encoded / decoded is referred to as the current picture. When a block in the current picture is similar to a reference block in a reference picture that was previously encoded in the video and is still buffered, the block in the current picture may be encoded by a vector called a motion vector. The motion vector points to a reference block in a reference picture, and in the case where multiple reference pictures are used, the motion vector may have a third dimension that identifies the reference picture.

[0100] In some embodiments, bidirectional prediction techniques may be used in inter-picture prediction. According to the bidirectional prediction technique, two reference pictures are used, for example, a first reference picture and a second reference picture that are both before the current picture in the video in decoding order (but may be in the past and future in display order, respectively). A block in the current picture may be encoded by a first motion vector pointing to a first reference block in the first reference picture and a second motion vector pointing to a second reference block in the second reference picture. Specifically, the block may be predicted by a combination of the first reference block and the second reference block.

[0101] In addition, merge mode technology can be used in inter-picture prediction to improve coding efficiency.

[0102] According to some embodiments disclosed in the present application, predictions such as inter-picture prediction and intra-picture prediction are performed in blocks. For example, according to the HEVC standard, pictures in a video picture sequence are divided into coding tree units (CTUs) for compression, and the CTUs in the pictures have the same size, such as 64×64 pixels, 32×32 pixels, or 16×16 pixels. In general, a CTU includes three coding tree blocks (CTBs), which are a luminance CTB and two chrominance CTBs. Furthermore, each CTU can be split into one or more coding units (CUs) using a quadtree. For example, a 64×64 pixel CTU can be split into a 64×64 pixel CU, or 4 32×32 pixel CUs, or 16 16×16 pixel CUs. In an embodiment, each CU is analyzed to determine the prediction type for the CU, such as an inter-prediction type or an intra-prediction type. In addition, depending on temporal and / or spatial predictability, the CU is split into one or more prediction units (PUs). Typically, each PU includes a luminance prediction block (PB) and two chrominance PBs. In an embodiment, the prediction operation in encoding (encoding / decoding) is performed in units of prediction blocks. Taking the luminance prediction block as an example of a prediction block, the prediction block includes a matrix of pixel values ​​(e.g., luminance values), such as 8×8 pixels, 16×16 pixels, 8×16 pixels, 16×8 pixels, and the like.

[0103] Figure 7 is an exemplary diagram of a video encoder (703). The video encoder (703) is configured to receive a processed block (e.g., a prediction block) of sample values ​​within a current video picture in a sequence of video pictures and encode the processed block into an encoded picture that is part of an encoded video sequence. In this embodiment, the video encoder (703) is configured to replace Figure 4 A video encoder (403) in an embodiment.

[0104] In an HEVC embodiment, a video encoder (703) receives a matrix of sample values ​​for a processing block, such as a prediction block of 8×8 samples. The video encoder (703) uses, for example, rate-distortion (RD) optimization to determine whether to use intra mode, inter mode, or bidirectional prediction mode to encode the processing block. When encoding the processing block in intra mode, the video encoder (703) may use intra prediction techniques to encode the processing block into an encoded picture; and when encoding the processing block in inter mode or bidirectional prediction mode, the video encoder (703) may use inter prediction or bidirectional prediction techniques to encode the processing block into an encoded picture, respectively. In some video encoding techniques, the merge mode may be an inter-picture prediction submode, in which a motion vector is derived from one or more motion vector predictors without the aid of an encoded motion vector component external to the predictor. In some other video encoding techniques, there may be a motion vector component applicable to the subject block. In an embodiment, the video encoder (703) includes other components, such as a mode decision module (not shown) for determining the processing block mode.

[0105] exist Figure 7 In an embodiment of the present invention, the video encoder (703) includes: Figure 7 Shown are an inter-frame encoder (730), an intra-frame encoder (722), a residual calculator (723), a switch (726), a residual encoder (724), a general controller (721), and an entropy encoder (725) coupled together.

[0106] The inter-frame encoder (730) is used to receive samples of a current block (e.g., a processing block), compare the block with one or more reference blocks in a reference picture (e.g., blocks in a previous picture and a subsequent picture), generate inter-frame prediction information (e.g., redundant information description according to an inter-frame coding technique, motion vectors, merge mode information), and calculate an inter-frame prediction result (e.g., a predicted block) based on the inter-frame prediction information using any suitable technique. In some embodiments, the reference picture is a decoded reference picture decoded based on the encoded video information.

[0107] The intra-frame encoder (722) is used to receive samples of a current block (e.g., a processing block), compare the block with an encoded block in the same picture in some cases, generate quantization coefficients after transformation, and in some cases also generate intra-frame prediction information (e.g., intra-frame prediction direction information according to one or more intra-frame coding techniques). In an embodiment, the intra-frame encoder (722) also calculates an intra-frame prediction result (e.g., a predicted block) based on the intra-frame prediction information and a reference block in the same picture.

[0108] The general controller (721) is used to determine the general control data and control other components of the video encoder (703) based on the general control data. In an embodiment, the general controller (721) determines the mode of the block and provides a control signal to the switch (726) based on the mode. For example, when the mode is intra mode, the general controller (721) controls the switch (726) to select the intra mode result for use by the residual calculator (723) and controls the entropy encoder (725) to select intra prediction information and add the intra prediction information to the bitstream; and when the mode is inter mode, the general controller (721) controls the switch (726) to select the inter prediction result for use by the residual calculator (723) and controls the entropy encoder (725) to select the inter prediction information and add the inter prediction information to the bitstream.

[0109] The residual calculator (723) is used to calculate the difference (residual data) between the received block and the prediction result selected from the intra-frame encoder (722) or the inter-frame encoder (730). The residual encoder (724) is used to operate based on the residual data to encode the residual data to generate a transform coefficient. In an embodiment, the residual encoder (724) is used to convert the residual data from the time domain to the frequency domain and generate a transform coefficient. The transform coefficient is then processed by quantization to obtain a quantized transform coefficient. In various embodiments, the video encoder (703) also includes a residual decoder (728). The residual decoder (728) is used to perform an inverse transform and generate decoded residual data. The decoded residual data can be used appropriately by the intra-frame encoder (722) and the inter-frame encoder (730). For example, the inter-frame encoder (730) can generate a decoded block based on the decoded residual data and the inter-frame prediction information, and the intra-frame encoder (722) can generate a decoded block based on the decoded residual data and the intra-frame prediction information. The decoded blocks are appropriately processed to generate a decoded picture, and in some embodiments, the decoded picture may be buffered in a memory circuit (not shown) and used as a reference picture.

[0110] The entropy encoder (725) is used to format the bitstream to generate an encoded block. The entropy encoder (725) generates various information in the bitstream according to a suitable standard such as the HEVC standard. In an embodiment, the entropy encoder (725) is used to obtain general control data, selected prediction information (such as intra-frame prediction information or inter-frame prediction information), residual information, and other suitable information in the bitstream. It should be noted that according to the disclosed subject matter, when a block is encoded in an inter-frame mode or a merge sub-mode of a bidirectional prediction mode, there is no residual information.

[0111] Figure 8is an example diagram of a video decoder (810). The video decoder (810) is used to receive an encoded image as part of an encoded video sequence and decode the encoded image to generate a reconstructed picture. In an embodiment, the video decoder (810) is used to replace Figure 4 A video decoder (410) of an embodiment.

[0112] exist Figure 8 In an embodiment, the video decoder (810) includes Figure 8 An entropy decoder (871), an inter-frame decoder (880), a residual decoder (873), a reconstruction module (874) and an intra-frame decoder (872) coupled together are shown in FIG.

[0113] The entropy decoder (871) may be used to reconstruct certain symbols from the encoded picture, which represent syntax elements constituting the encoded picture. Such symbols may include, for example, a mode for encoding the block (e.g., intra mode, inter mode, bidirectional prediction mode, a merged sub-mode of the latter two, or another sub-mode), prediction information (e.g., intra prediction information or inter prediction information) that may identify certain samples or metadata for prediction by the intra decoder (872) or the inter decoder (880), respectively, residual information in the form of, for example, quantized transform coefficients, and the like. In an embodiment, when the prediction mode is inter or bidirectional prediction mode, the inter prediction information is provided to the inter decoder (880); and when the prediction type is an intra prediction type, the intra prediction information is provided to the intra decoder (872). The residual information may be inverse quantized and provided to the residual decoder (873).

[0114] The inter-frame decoder (880) is used to receive the inter-frame prediction information and generate an inter-frame prediction result based on the inter-frame prediction information.

[0115] The intra-frame decoder (872) is used to receive intra-frame prediction information and generate a prediction result based on the intra-frame prediction information.

[0116] The residual decoder (873) is used to perform inverse quantization to extract dequantized transform coefficients, and process the dequantized transform coefficients to convert residual information from the frequency domain to the spatial domain. The residual decoder (873) may also require some control information (to obtain the quantizer parameter QP), and this information can be provided by the entropy decoder (871) (the data path is not indicated because this is only low-volume control information).

[0117] The reconstruction module (874) is used to combine the residual output by the residual decoder (873) with the prediction result (which can be output by the inter-frame prediction module or the intra-frame prediction module) in the spatial domain to form a reconstructed block, which can be part of a reconstructed picture, which in turn can be part of a reconstructed video. It should be noted that other suitable operations such as deblocking operations can be performed to improve visual quality.

[0118] It should be noted that the video encoder (403), video encoder (603) and video encoder (703) and video decoder (410), video decoder (510) and video decoder (810) may be implemented using any suitable technology. In an embodiment, the video encoder (403), video encoder (603) and video encoder (703) and video decoder (410), video decoder (510) and video decoder (810) may be implemented using one or more integrated circuits. In another embodiment, the video encoder (403), video encoder (603) and video encoder (703) and video decoder (410), video decoder (510) and video decoder (810) may be implemented using one or more processors that execute software instructions.

[0119] The present disclosure includes embodiments involving dividing a merge candidate type or a merge candidate group into multiple subgroups. The merge candidate types can be divided based on the characteristics of the merge candidates. Further, the merge candidates within each subgroup can be reordered. For example, multiple merge candidate types can also be reordered based on relative template matching costs. For example, based on the characteristics of the merge candidates within each subgroup, each merge candidate type can be divided into two or more subgroups, and the merge candidates within each subgroup can be adaptively reordered. Adaptive reordering can also be applied to the merge candidate types based on the relative template matching cost of each merge candidate type.

[0120] ITU-T VCEG (Q6 / 16) and ISO / IEC MPEG (JTC 1 / SC 29 / WG 11) released the H.265 / HEVC (High Efficiency Video Coding) standard in 2013 (version 1), 2014 (version 2), 2015 (version 3), and 2016 (version 4). In 2015, the two standards organizations jointly formed JVET (Joint Video Exploration Team) to explore the potential of developing the next video coding standard beyond HEVC. In October 2017, the two standards organizations issued a joint call for proposals (CfP) for video compression with capabilities beyond HEVC. As of February 15, 2018, 22 CfP responses for standard dynamic range (SDR), 12 CfP responses for high dynamic range (HDR), and 12 CfP responses for 360 video categories have been submitted. In April 2018, at the 122nd MPEG meeting / 10th JVET meeting, all received CfP replies were evaluated. As a result of this meeting, JVET officially launched the standardization process for the next generation of video coding beyond HEVC. The new standard was named Versatile Video Coding (VVC), and JVET was renamed the Joint Video Experts Group. In 2020, ITU-T VCEG (Q6 / 16) and ISO / IEC MPEG (JTC 1 / SC 29 / WG 11) released the VVC video coding standard (version 1).

[0121] In inter prediction, for each inter prediction coding unit (CU, coding unit), the coding feature of VVC requires motion parameters, for example, for inter prediction sample generation. Motion parameters may include motion vectors, reference picture indices, reference picture list usage indices, and / or additional information. Motion parameters may be signaled explicitly or implicitly. When a CU is encoded in skip mode, the CU may be associated with one PU, and valid residual coefficients, encoded motion vector increments, and / or reference picture indices may not be required. When a CU is encoded in merge mode, motion parameters for the CU may be obtained from neighboring CUs. Neighboring CUs may include spatial and temporal candidates, as well as additional scheduling (or additional candidates) introduced, for example, in VVC. Merge mode may be applied to any inter prediction CU, not just to skip mode. An alternative to merge mode is explicit transmission of motion parameters, where motion vectors, corresponding reference picture indices for each reference picture list, reference picture list usage flags, and / or other required information may be explicitly signaled for each CU.

[0122] In VVC, the VVC Test model (VTM) reference software may include some new and improved inter-frame prediction coding tools, which may include one or more of the following:

[0123] (1) Extended Merger Forecast

[0124] (2) Merge motion vector difference (MMVD)

[0125] (3) AMVP mode with symmetric MVD signaling

[0126] (4) Affine Motion Compensated Prediction

[0127] (5) Subblock-based temporal motion vector prediction (SbTMVP)

[0128] (6) Adaptive motion vector resolution (AMVR)

[0129] (7) Sports field storage: 1 / 16 th Luma sample MV storage and 8×8 motion field compression

[0130] (8) Bi-prediction with CU-level weights (BCW)

[0131] (9) Bi-directional optical flow (BDOF)

[0132] (10) Decoder side motion vector refinement (DMVR)

[0133] (11) Combined inter and intra prediction (CIIP)

[0134] (12) Geometric partitioning mode (GPM)

[0135] For example, in VTM 4, the merge candidate list may be constructed by including five types of candidates. The merge candidate list may be constructed in the following order:

[0136] (1) Spatial MVP from spatially neighboring CUs,

[0137] (2) Time MVP from the same CU,

[0138] (3) History-based MVP from FIFO table,

[0139] (4) Pairwise average MVP, and

[0140] (5) Zero MV.

[0141] The size of the merge list may be signaled in the slice header. For example, in VTM 4, the maximum size allowed for the merge list may be 6. For each CU encoded in merge mode, the index of the best merge candidate may be encoded, for example using truncated unary binarization. The first bin of the merge index may be encoded with context, and bypass coding may be used for the other bins.

[0142] In spatial candidate derivation, for example, the derivation of spatial merge candidates in VVC may be the same or similar to the derivation of spatial merge candidates in HEVC. Fig. 9 The maximum number of merge candidates (for example, four merge candidates) is selected from the candidates at the illustrated position. Fig. 9 As shown, the current block (901) may include neighboring blocks (902) to (906) located at positions A0, A1, B0, B1, and B2, respectively. The order of derivation of spatial merge candidates may be B1, A1, B0, A0, and B2. Position B2 may be considered only when any CU (or block) at position A0, B0, B1, or A1 is unavailable (for example, because the CU belongs to another slice or tile) or when intra coding is performed. After adding the candidate (or block) at position A1, a redundancy check may be performed on the addition of the remaining candidates (or blocks). The redundancy check may ensure that candidates with the same motion information are excluded from the merge list, thereby improving coding efficiency. In order to reduce computational complexity, the redundancy check may not consider all possible candidate pairs. Instead, only pairs with the same motion information may be considered. Fig.10 . For example, redundancy check can be applied to 5 candidate pairs, such as candidate pairs of A1 and B1 and candidate pairs of A1 and A0. A candidate can be added to the merge list only if the corresponding candidate for redundancy check does not include the same motion information. For example, candidate B0 can be added to the merge list only if the corresponding candidate B1 does not include the same motion information.

[0143] In temporal candidate derivation, only one candidate can be added to the merge list. Fig.11As shown, when deriving a temporal merge candidate for the current CU (1114), a scaled motion vector can be derived based on the co-located CU (1104) belonging to the co-located reference picture (1112). The reference picture list used to derive the co-located CU (1104) can be explicitly signaled in the slice header. Fig.11 As shown in the dashed line (1102) in FIG. 1 , a scaled motion vector for a temporal merge candidate may be obtained, where it is scaled from the motion vector of the co-located CU (1104) using picture order count (POC) distances tb and td. tb may be defined as the POC difference between the reference picture of the current picture (e.g., Curr_ref) (1106) and the current picture (e.g., Curr_pic) (1108). td may be defined as the POC difference between the reference picture of the co-located picture (e.g., Col_ref) (1110) and the co-located picture (e.g., Col_pic) (1112). The reference picture index of the temporal merge candidate may be set equal to zero.

[0144] like Fig.12 As shown, the position of the temporal candidate can be selected between candidates C0 and C1. For example, if the CU at position C0 is not available, intra-coded, or outside the current row of the CTU, position C1 can be used. Otherwise, position C0 can be used to derive a temporal merge candidate.

[0145] To further improve compression efficiency, enhanced compression tools beyond the capabilities of VVC are needed.

[0146] In an example, template matching (TM) for correcting motion at the decoding end may be provided. In TM mode, motion is corrected by constructing a template from left and top adjacent reconstructed samples and finding the closest match between the templates in the current picture and the reference picture.

[0147] like Fig.13As shown, the current block (or CU) (1304) may be included in the current frame (1306). Neighboring samples at the top and / or left side of the adjacent current CU (1304) may form a current template (1308) of the current CU (1304). A better (or improved) MV may be obtained by searching around the initial motion (1302) of the current CU (1304) within a search range of [-8, +8] pixels in a reference frame (1310). A better MV may be determined based on a reference block indicated by a better MV in the reference frame (1310), wherein the difference (or TM cost) between the reference template (1312) of the reference block and the current template (1308) of the current block (1304) is minimized in the search range. For example, the search step size may be determined by an adaptive motion vector range (AMVR) mode, and the TM may be cascaded with a bidirectional matching process.

[0148] In an example, non-contiguous spatial merge candidates may be provided.Non-contiguous spatial merge candidates may be inserted into a regular merge candidate list after a temporal MV predictor (TMVP). Fig.14 An exemplary pattern (1400) of spatial merging candidates is shown in FIG. Fig.14 As shown, the mode (1400) may include neighboring spatial merge candidates 1 to 5 and non-neighboring spatial merge candidates 6 to 23 for the current coding block (1402). The distance between the non-neighboring spatial merge candidates and the current coding block (1402) may be based on the width and / or height of the current coding block (1402).

[0149] Adaptive reordering of merge candidates based on template matching (ARMC) may be provided. ARMC may be applied to conventional merge mode, template matching (TM) merge mode, and affine merge mode (excluding SbTMVP candidates). For TM merge mode, the merge candidates may be reordered before the correction process. After constructing the merge candidate list, the merge candidates may be divided into several subgroups. The subgroup size of each subgroup may be set to any number, such as 5. The merge candidates in each subgroup may be reordered in ascending order according to the cost value based on template matching. For simplicity, the merge candidates in the last but not the first subgroup may not be reordered. For sub-block-based merge candidates with a sub-block size equal to Wsub*Hsub, the template above may include several sub-templates of size Wsub×1, and the template on the left may include several sub-templates of size 1×Hsub. Wsub may be the width of the sub-block, and Hsub may be the height of the sub-block.

[0150] Fig.15 An exemplary derivation of sub-block based merge candidates can be shown. Fig.15 As shown, the current block (1502) may be included in the current picture (1504). The current block (1502) may include sub-blocks A to G in the first row and the first column. The current block (1502) may include a template (1506) adjacent to the top and left sides of the current block (1502). The current block (1502) may include a co-located block (1508) in the reference picture (1510). The co-located block (1508) may include sub-blocks A to G in the first row and the first column, and the sub-blocks A to G correspond to the sub-blocks A to G in the current block (1502). Motion information (e.g., affine motion vectors) of the sub-blocks A to G in the first row and the first column of the current block (1502) may be used to derive reference samples of a sub-template (or sub-reference template) of the co-located block (1508). For example, the motion information of sub-blocks A, E, F, and G of the current block (1502) may be applied to derive reference samples of sub-templates at left positions of sub-blocks A, E, F, and G of the adjacent co-located block (1508). The sub-templates at the left of sub-blocks A, E, F, and G of the adjacent co-located block (1508) may form the left reference template of the co-located block (1508). The motion information of sub-blocks A, B, C, and D of the current block (1502) may be applied to derive reference samples of sub-templates at top positions of sub-blocks A, B, C, and D of the adjacent co-located block (1508). The sub-templates at the top of sub-blocks A, B, C, and D of the adjacent co-located block (1508) may further form the upper reference template of the co-located block (1508).

[0151] Non-neighboring candidates and HMVP candidates can be placed behind neighboring candidates and TMVP candidates in a merge candidate list based on a predefined traversal order, such as in ECM and EE2. A template-matching based merge candidate list construction (TM-MCLC) can be provided to place non-neighboring candidates and HMVP candidates behind neighboring candidates and TMVP candidates in a merge candidate list in ascending order of template matching cost. All available non-neighboring motion vector predictors (MVP) and history-based motion vector predictors (HMVP) can be collected in a group. The TM cost associated with each candidate in the group can be derived in a manner similar to ARMC. Further, all candidates in the group can be sorted in ascending order based on the corresponding TM cost. Finally, non-neighboring candidates and HMVP candidates can be placed in a merge candidate list based on ascending order of template matching cost. Neighboring MVP in ECM software such as TM-MCLC can be further extended with more spatial and non-neighboring time locations. An exemplary pattern (1600) of the location of the MVP of the current block (1608) may be as follows: Fig.16 As shown. Fig.16 As shown, the pattern (1600) may include 18 non-adjacent spatial MVP positions in ECM-2.0 (1602), an additional (or newly added) 32 non-adjacent spatial positions (or MVPs) (1604), and 12 non-adjacent temporal positions (or MVPs) (1606), wherein the non-adjacent temporal MVP positions may be positioned in the same reference frame as the adjacent TMVPs.

[0152] Based on the TM cost value, the ARMC based on the MV candidate type can be used to reorder the merge candidates in candidate types such as TMVP, NA-MVP, etc. Then, when constructing the merge candidate list, M candidates can be selected from the reordered candidates based on the candidate type. M can vary with the candidate type. For example, for the TMVP type, M=1, and for the NA-MVP type, M=9. Some candidate types can add more merge candidates for reordering and selection. For example, TMVP candidates derived from different collocated positions can be reordered together, and a candidate can be selected from the reordered TMVP candidates, and the collocated positions include the lower right and center positions.

[0153] Still reference Fig.16, a total of 62 merge candidates can be applied to the construction of the non-adjacent spatial merge candidate list. The 62 merge candidates are put into groups by sorting the corresponding TM costs in ascending order. Therefore, a complex sorting operation is required to sort the 62 merge candidates. In addition, extended merge candidates can be provided in the merge candidate list above the ECM software to further improve the compression efficiency. After adding the extended merge candidates, the size of the merge candidate list can quickly increase, and the entropy encoding of large merge candidate indexes may not be very efficient.

[0154] In the present disclosure, a merge candidate list of a current block may be generated based on available merge candidates. For example, non-adjacent spatial merge candidates and / or other merge candidates of the current block may be included to generate a merge candidate list. Non-adjacent spatial merge candidates and / or other merge candidates may be divided into more than one subgroup.

[0155] For each subgroup, the merge candidates within the corresponding subgroup may be sorted in order (such as ascending order) based on a parameter (e.g., a cost value). For example, the merge candidates within each subgroup may be sorted in ascending order based on the corresponding TM costs of the merge candidates. The subgroups may be further reordered in the merge candidate list to generate a reordered merge candidate list. In the example, the subgroups may be reordered in ascending order based on a feature parameter (e.g., a feature cost value) in the merge candidate list. The feature cost value of the subgroup may be the minimum TM cost of the subgroup, the median TM cost of the subgroup, the average TM cost of the subgroup, etc.

[0156] In an embodiment, non-adjacent spatial merging candidates may be Fig.16 The non-adjacent spatial merge candidates shown. The non-adjacent spatial merge candidates can be classified (or divided) into multiple subgroups, for example, 3 subgroups. The first subgroup may include the non-adjacent spatial MVP (or candidate) at position (1602). Fig.16 As shown, the non-adjacent space MVP can be positioned at an angle of π / 4, an angle of π / 2, an angle of 3π / 4, an angle of π, and an angle of 5π / 4 relative to the horizontal axis (e.g., the X axis). The second subgroup can include the non-adjacent space MVP newly added at the position (1604). Fig.16 As shown, the newly added non-adjacent MVP can be positioned at an angle of π / 4, an angle of 3π / 8, an angle of π / 2, an angle of 5π / 8, an angle of 3π / 4, an angle of 7π / 8, an angle of π, an angle of 9π / 8, and an angle of 5π / 4 relative to the horizontal axis. For example, the third subgroup can include a non-adjacent time MVP at position (1606).

[0157] All merge candidates of each subgroup may be sorted in an order such as ascending order based on the TM costs of the merge candidates in the corresponding subgroup. The corresponding TM cost value of each merge candidate may be determined based on the difference between the current template (or adjacent neighboring sample) of the current block and the reference template (or adjacent neighboring sample) of the corresponding merge candidate. Fig.13 An exemplary current template and a reference template are shown. The TM cost may be calculated based on one of mean square error (MSE), mean absolute difference (MAD), sum of absolute difference (SAD), sum of absolute transformed difference (SATD), partial SAD, etc.

[0158] In an embodiment, the subset of candidates in the merge candidate list may be placed in the merge candidate list in a predefined order. The predefined order may be signaled in the bitstream, for example in an SPS, PPS, picture header and / or slice header.

[0159] In an embodiment, the candidate subgroups in the merge candidate list may be reordered in the merge candidate list. The subgroups may be reordered according to the corresponding TM cost (or characteristic TM cost) of each subgroup.

[0160] In the example, the minimum TM cost of each subgroup can be used to determine the order of constructing the non-adjacent spatial merge candidate list. Therefore, the corresponding minimum TM cost of each subgroup can be determined first. The subgroups can be reordered in ascending order based on the minimum TM cost. For example, Fig.16 As shown, the non-adjacent spatial merge candidate list may include three subgroups. When the minimum TM cost of the third subgroup is less than the minimum TM cost of the second subgroup, and the minimum TM cost of the second subgroup is less than the minimum TM cost of the first subgroup, the three subgroups may be placed in the order of subgroup #3 < subgroup #2 < subgroup #1, which means that the third subgroup may be placed first in the non-adjacent spatial merge candidate list. In the non-adjacent spatial merge candidate list, the second subgroup may be placed after the third subgroup, and the first subgroup may be placed after the second subgroup.

[0161] In an example, the median TM cost of each subgroup may be used to determine the order of non-contiguous spatial merge candidate list construction. The subgroups may be reordered in an order such as ascending order based on the median TM cost of each subgroup.

[0162] In an example, if the size of the subgroup is greater than 1, the average of the TM costs of each subgroup, such as the first two smallest TM costs, may be applied to determine the order of non-adjacent spatial merge candidate list construction. The subgroups may be reordered in an order, such as ascending order, based on the average of the first two smallest TM costs of each subgroup.

[0163] In an example, a median TM cost in a subset of TM costs of each subgroup may be applied to determine the order of non-adjacent spatial merge candidate list construction, wherein the median TM cost in the subset of TM costs may be, for example, the median TM cost in a subset of the first n smallest TM costs. In an example, if the size of the subgroup is greater than 2, the median TM cost in the subset of TM costs is used. n may be a positive integer equal to or greater than 2. The subgroups may be reordered in an order such as ascending order based on the median TM cost of the first n smallest TM costs of each subgroup.

[0164] In the present disclosure, a merge candidate list of the current block may be further constructed based on at least one of (1) spatial motion vector (MV) prediction values ​​of spatial neighboring blocks of the current block, (2) temporal MV prediction values ​​of co-located blocks of the current block, (3) history-based MV prediction values ​​from a first-in-first out (FIFO) table, (4) pairwise average MV prediction values, or (5) zero MV.

[0165] The merge candidates in the merge candidate list may be further divided into more than one group (or subgroup). For example, the merge candidates in the merge candidate list may be divided into multiple groups based on the same number of merge candidates, a predefined number of merge candidates, or merge candidates of the same type (or attribute). For example, a first group may be formed based on a first type of merge candidate, such as a spatial MV prediction value of a spatial neighboring block from a neighboring block of a current block. A second group may be formed based on a second type of merge candidate, such as a temporal MV prediction value of a co-located block from a current block.

[0166] Before the merge candidate list is constructed, a TM program may be performed on the merge candidates in the merge candidate list (e.g., all merge candidates) to obtain the TM cost of the merge candidates. The order in which the merge candidate list of each group is constructed may be determined according to the corresponding TM cost of each group. For example, the TM cost of the merge candidate in each group may be determined first. Based on the TM cost of the merge candidate, the merge candidates in each group are reordered. The groups may also be further reordered in the merge candidate list in order (such as ascending order) based on the corresponding TM cost (or characteristic TM cost) of each group.

[0167] In an embodiment, the minimum TM cost of each group may be applied to determine the order in which the merge candidate list is constructed. Therefore, the corresponding minimum TM cost of each group may be determined first. The groups may be reordered in ascending order based on the minimum TM cost. For example, the merge candidates in the merge candidate list may be divided into three groups. When the minimum TM cost of the third group is less than the minimum TM cost of the second group, and the minimum TM cost of the second group is less than the minimum TM cost of the first group, the third group may be placed in the merge candidate list first. In the merge candidate list, the second group may be placed after the third group, and the first group may be placed after the second group.

[0168] In an embodiment, the median TM cost of each group may be applied to determine the order of merge candidate list construction. The groups may be reordered in an order such as ascending order based on the median TM cost of each group.

[0169] In an embodiment, if the size of the groups is greater than 1, the average of the first two smallest TM costs of each group may be applied to determine the order of merge candidate list construction. The groups may be reordered in an order such as ascending based on the average of the first two smallest TM costs of each group.

[0170] In an embodiment, the median TM cost of a subset of the first n smallest TM costs of each group may be applied to determine the order of construction of the merge candidate list. For example, if the size of the groups is greater than 2, the median TM cost of the subset of TM costs may be applied. n may be a positive integer equal to or greater than 2. The groups may be reordered in an order such as ascending order based on the median TM cost of the first n smallest TM costs of each group.

[0171] Fig.17 A flow chart outlining an exemplary decoding process (1700) is shown according to some embodiments of the present disclosure. Fig.18 A flow chart outlining an exemplary encoding process (1800) according to some embodiments of the present disclosure is shown. The proposed process can be used alone or in combination in any order. Further, each of the process (or embodiment), encoder, and decoder can be implemented by a processing circuit system (e.g., one or more processors or one or more integrated circuits). In one example, one or more processors execute a program stored in a non-volatile computer-readable medium.

[0172] The operations of the processes (eg, (1700) and (1800)) may be combined or arranged in any number or order as desired. In an embodiment, two or more of the operations of the processes (eg, (1700) and (1800)) may be performed in parallel.

[0173] The process (e.g., (1700) and (1800)) can be used to reconstruct and / or encode a block so as to generate a prediction block for the block under reconstruction. In various embodiments, the process (e.g., (1700) and (1800)) is performed by a processing circuit, such as a processing circuit in a terminal device (310), (320), (330), and (340); a processing circuit that performs the functions of a video encoder (403); a processing circuit that performs the functions of a video decoder (410); a processing circuit that performs the functions of a video decoder (510); a processing circuit that performs the functions of a video encoder (603), etc. In some embodiments, the process (e.g., (1700) and (1800)) is implemented in software instructions, so when the processing circuit executes the software instructions, the processing circuit performs the process (e.g., (1700) and (1800)).

[0174] like Fig.17 As shown, the process (1700) may start from (S1701) and proceed to (S1710). In (S1710), encoded information of a current block and neighboring blocks of the current block in a current picture may be received from an encoded video code stream.

[0175] In (S1720), a merge candidate list of the current block may be generated according to neighboring blocks of the current block.

[0176] In (S1730), the merge candidate list of the current block may be divided into a plurality of subgroups. Each of the plurality of subgroups may include one or more merge candidates. The one or more merge candidates may be sorted within each subgroup according to a corresponding TM cost associated with each of the one or more merge candidates.

[0177] In (S1740), the current block may be reconstructed according to the merge candidate selected from the merge candidate list of the current block.

[0178] In the process ( 1700 ), the plurality of subgroups in the merge candidate list may be further reordered according to the respective TM cost value associated with each of the plurality of subgroups.

[0179] In order to reorder the multiple subgroups in the merge candidate list, a TM cost value associated with each of the multiple subgroups may be first determined. The multiple subgroups in the merge candidate list may be further reordered based on the ascending order of the TM cost values ​​associated with the multiple subgroups. Therefore, the first subgroup in the multiple subgroups in the reordered merge candidate list may be associated with the minimum TM cost value in the TM cost values.

[0180] In order to determine a corresponding TM cost value associated with each of the plurality of subgroups, a plurality of TM cost values ​​of one or more merge candidates in a first subgroup of the plurality of subgroups may be determined. Each of the TM cost values ​​may be associated with a difference between an adjacent neighboring sample of the current block and an adjacent neighboring sample of a corresponding merge candidate in the first subgroup. The one or more merge candidates in the first subgroup of the plurality of subgroups may be reordered based on an ascending order of the plurality of TM cost values ​​of the one or more merge candidates in the first subgroup, so that the reordered first merge candidate in the first subgroup has a minimum TM cost value.

[0181] In an embodiment, the TM cost value associated with a first subgroup among the plurality of subgroups may be determined as a minimum TM cost value among a plurality of TM cost values ​​of one or more merge candidates in the first subgroup.

[0182] In an embodiment, the TM cost value associated with a first subgroup of the plurality of subgroups may be determined as a median TM cost value among a plurality of TM cost values ​​of one or more merge candidates in the first subgroup.

[0183] In one embodiment, the TM cost value associated with a first subgroup of the plurality of subgroups may be determined as a median TM cost value among a plurality of minimum TM cost values ​​among a plurality of TM cost values ​​of one or more merge candidates in the first subgroup.

[0184] In an embodiment, the TM cost value associated with a first subgroup of the plurality of subgroups may be determined as an average of first two minimum TM cost values ​​of the plurality of TM cost values ​​of the one or more merge candidates in the first subgroup.

[0185] In process (1700), a merge candidate list for the current block may be generated based on at least one of a spatial motion vector (MV) prediction value of a spatial neighboring block from a neighboring block of the current block, a temporal MV prediction value from a co-located block of the current block, a history-based MV prediction value from a first-in-first-out (FIFO) table, a pairwise average MV prediction value, a zero MV, a non-neighboring MV prediction value of a non-neighboring spatial neighboring block from a neighboring block of the current block, or a non-neighboring temporal MV prediction value of the current block.

[0186] According to a merge candidate list including non-adjacent MV prediction values ​​and non-adjacent time MV prediction values, the merge candidate list is divided into a first subgroup including a first group of non-adjacent MV prediction values, the first group of non-adjacent MV prediction values ​​are positioned at an angle of π / 4, an angle of π / 2, an angle of 3π / 4, an angle of π, and an angle of 5π / 4 relative to the horizontal axis. The merge candidate list can also be divided into a second subgroup including a second group of non-adjacent MV prediction values, the second group of non-adjacent MV prediction values ​​are positioned at an angle of π / 4, an angle of 3π / 8, an angle of π / 2, an angle of 5π / 8, an angle of 3π / 4, an angle of 7π / 8, an angle of π, an angle of 9π / 8, and an angle of 5π / 4 relative to the horizontal axis.

[0187] The merge candidate list may be further divided into a third subgroup including non-contiguous temporal MV prediction values.

[0188] In some embodiments, the merge candidate list may be divided into a plurality of sub-groups such that each of the plurality of sub-groups may include one of the same number of merge candidates, a predefined number of merge candidates, or the same type of merge candidates.

[0189] After (S1740), the process proceeds to (S1799) and terminates.

[0190] The process (1700) may be modified as appropriate. One or more steps in the process (1700) may be improved and / or omitted. Additional one or more steps may be added. Any suitable order of implementation may be used.

[0191] like Fig.18 As shown, the process (1800) may start from (S1801) and proceed to (S1810). In (S1810), a merge candidate list of the current block may be generated according to neighboring blocks of the current block in the current picture.

[0192] In (S1820), the merge candidate list of the current block may be divided into a plurality of sub-groups, wherein each of the plurality of sub-groups may include one or more merge candidates.

[0193] In (S1830), the plurality of subgroups in the merge candidate list may be reordered according to a corresponding TM cost value associated with each of the plurality of subgroups.

[0194] In (S1840), prediction information of the current block may be generated according to the merge candidate selected from the reordered merge candidate list of the current block.

[0195] Then, the process proceeds to (S1899) and terminates.

[0196] The process (1800) may be modified as appropriate. One or more steps in the process (1800) may be improved and / or omitted. Additional one or more steps may be added. Any suitable order of implementation may be used.

[0197] The above techniques may be implemented as computer software via computer-readable instructions and physically stored in one or more computer-readable media. Fig.19 A computer device (1900) is shown that is suitable for implementing certain embodiments of the disclosed subject matter.

[0198] The computer software may be encoded in any suitable machine code or computer language, and may be assembled, compiled, linked, or the like to create a code comprising instructions, which may be directly executed by one or more computer central processing units (CPUs), graphics processing units (GPUs), etc., or executed by decoding, microcode, or the like.

[0199] The instructions may be executed on various types of computers or components thereof, including, for example, personal computers, tablets, servers, smartphones, gaming devices, IoT devices, etc.

[0200] Fig.19 The components shown for the computer device (1900) are exemplary in nature and are not intended to limit the scope of use or functionality of computer software implementing embodiments of the present application. The configuration of the components should not be interpreted as having any dependency or requirement on any component or combination of components shown in the exemplary embodiment of the computer device (1900).

[0201] The computer device (1900) may include certain human-computer interface input devices. Such human-computer interface input devices may respond to input from one or more human users through tactile input (e.g., keyboard input, sliding, data glove movement), audio input (e.g., sound, applause), visual input (e.g., gestures), and olfactory input (not shown). The human-computer interface device may also be used to capture certain media that are not necessarily directly related to human conscious input, such as audio (e.g., speech, music, ambient sound), images (e.g., scanned images, photographic images obtained from a still image camera), and videos (e.g., two-dimensional video, three-dimensional video including stereoscopic video).

[0202] The human-computer interface input device may include one or more of the following (only one of which is drawn): keyboard (1901), mouse (1902), touchpad (1903), touch screen (1910), data gloves (not shown), joystick (1905), microphone (1906), scanner (1907), camera (1908).

[0203] The computer device (1900) may also include certain human-computer interface output devices. Such human-computer interface output devices may stimulate one or more human user senses through, for example, tactile output, sound, light, and smell / taste. Such human-computer interface output devices may include tactile output devices (e.g., tactile feedback through a touch screen (1910), a data glove (not shown), or a joystick (1905), but there may also be tactile feedback devices that are not used as input devices), audio output devices (e.g., speakers (1909), headphones (not shown)), visual output devices (e.g., screens (1910) including cathode ray tube screens, liquid crystal screens, plasma screens, organic light emitting diode screens, each of which has or does not have a touch screen input function, each of which has or does not have a tactile feedback function - some of which may output two-dimensional visual output or output of more than three dimensions through means such as stereoscopic picture output; virtual reality glasses (not shown), holographic displays, and smoke boxes (not shown)) and printers (not shown).

[0204] The computer device (1900) may also include human-accessible storage devices and their associated media, such as optical media including high-density read-only / rewritable compact disks (CD / DVD ROM / RW) (1920) with CD / DVD or similar media (1921), thumb drives (1922), removable hard disk drives or solid state drives (1923), traditional magnetic media such as tapes and floppy disks (not shown), special-purpose ROM / ASIC / PLD-based devices such as security software protectors (not shown), and the like.

[0205] Those skilled in the art should also understand that the term "computer-readable media" used in connection with the disclosed subject matter does not include transmission media, carrier waves, or other transient signals.

[0206] The computer device (1900) may also include an interface (1955) to one or more communication networks (1954). The network may be wireless, wired, or optical. The network may also be a local area network, a wide area network, a metropolitan area network, an in-vehicle network, an industrial network, a real-time network, a delay-tolerant network, and the like. Examples of networks may include local area networks such as Ethernet, wireless local area networks, cellular networks (GSM, 3G, 4G, 5G, LTE, etc.), television wired or wireless wide area digital networks (including cable television, satellite television, and terrestrial broadcast television), in-vehicle and industrial networks (including CANBus), and the like. Some networks typically require an external network interface adapter for connecting to some universal data port or peripheral bus (1949) (e.g., a USB port of the computer device (1900)); other systems are typically integrated into the core of the computer device (1900) by connecting to a system bus as described below (e.g., an Ethernet interface integrated into a PC computer system or a cellular network interface integrated into a smart phone computer system). By using any of these networks, the computer device (1900) can communicate with other entities. The communication can be one-way, for receiving only (e.g., wireless television), one-way for sending only (e.g., CAN bus to certain CAN bus devices), or two-way, such as to other computer systems via a local or wide area digital network. Each of the above networks and network interfaces can use certain protocols and protocol stacks.

[0207] The above-mentioned human-machine interface devices, human-accessible storage devices, and network interfaces may be connected to the core (1940) of the computer device (1900).

[0208] The core (1940) may include one or more central processing units (CPUs) (1941), graphics processing units (GPUs) (1942), dedicated programmable processing units in the form of field programmable gate arrays (FPGAs) (1943), hardware accelerators for specific tasks (1944), etc. These devices, as well as read-only memory (ROM) (1945), random access memory (1946), internal mass storage (e.g., internal non-user accessible hard disk drives, solid-state drives, etc.) (1947), etc., may be connected via a system bus (1948). In some computer systems, the system bus (1948) may be accessed in the form of one or more physical plugs so that it may be expanded by additional central processing units, graphics processing units, etc. Peripheral devices may be directly attached to the core's system bus (1948) or connected via a peripheral bus (1949). The architecture of the peripheral bus includes PCI, USB, etc. In one example, the screen (1910) may be connected to a graphics adapter (1950). The architecture of the peripheral bus includes PCI, USB, etc.

[0209] The CPU (1941), GPU (1942), FPGA (1943) and accelerator (1944) can execute certain instructions, which can be combined to form the above-mentioned computer code. The computer code can be stored in ROM (1945) or RAM (1946). Transition data can also be stored in RAM (1946), while permanent data can be stored in, for example, internal mass storage (1947). Fast storage and retrieval of any memory device can be achieved by using a cache memory, which can be closely associated with one or more CPUs (1941), GPUs (1942), mass storage (1947), ROM (1945), RAM (1946), etc.

[0210] The computer readable medium may have computer code thereon for performing various computer-implemented operations. The medium and computer code may be specially designed and constructed for the purpose of this application, or may be medium and code well known and available to those skilled in the art of computer software.

[0211] As an example and not a limitation, a computer system having an architecture (1900), in particular a core (1940), can be provided as a processor (including a CPU, a GPU, an FPGA, an accelerator, etc.) to execute software contained in one or more tangible computer-readable media. Such a computer-readable medium can be a medium associated with the above-mentioned user-accessible mass storage, as well as a specific memory of the core (1940) having non-volatility, such as a core internal mass storage (1947) or a ROM (1945). Software implementing various embodiments of the present application can be stored in such a device and executed by the core (1940). Depending on specific needs, the computer-readable medium may include one or more storage devices or chips. The software can enable the core (1940), in particular the processor therein (including a CPU, a GPU, an FPGA, etc.) to perform a specific process or a specific part of a specific process described herein, including defining a data structure stored in the RAM (1946) and modifying such a data structure according to a software-defined process. Additionally or alternatively, the computer system may provide functionality hardwired in logic or otherwise contained in circuitry (e.g., accelerator (1944)) that may operate in place of or in conjunction with software to perform a particular process or a particular portion of a particular process described herein. Where appropriate, references to software may include logic and vice versa. Where appropriate, references to computer-readable media may include circuitry (e.g., an integrated circuit (IC)) storing the executing software, circuitry containing the executing logic, or both. The present application includes any suitable combination of hardware and software.

[0212] Appendix: Acronyms

[0213] JEM: Joint Development Model

[0214] VVC: Next Generation Video Coding

[0215] BMS: Benchmark Collection

[0216] MV: Motion Vector

[0217] HEVC: High Efficiency Video Coding

[0218] SEI: Supplemental Enhancement Information

[0219] VUI: Video Availability Information

[0220] GOPs: Group of Pictures

[0221] TUs: Transformation Units

[0222] PUs: prediction units

[0223] CTUs: Coding Tree Units

[0224] CTBs: Coding Tree Blocks

[0225] PBs: prediction blocks

[0226] HRD: Hypothesized Reference Decoder

[0227] SNR: Signal to Noise Ratio

[0228] CPUs: Central Processing Units

[0229] GPUs: Graphics Processing Units

[0230] CRT: cathode ray tube

[0231] LCD: Liquid crystal display

[0232] OLED: Organic Light Emitting Diode

[0233] CD: Compact Disc DVD: Digital Video Disc

[0234] ROM: Read Only Memory

[0235] RAM: Random Access Memory

[0236] ASIC: Application-Specific Integrated Circuit

[0237] PLD: Programmable Logic Device

[0238] LAN: Local Area Network

[0239] GSM: Global System for Mobile Communications

[0240] LTE: Long Term Evolution

[0241] CANBus: Controller Area Network Bus

[0242] USB: Universal Serial Bus

[0243] PCI: Peripheral Component Interconnect

[0244] FPGA: Field Programmable Gate Array

[0245] SSD: Field Programmable Gate Array

[0246] IC: Integrated Circuit

[0247] CU: Coding Unit

[0248] Although the present application has described a number of exemplary embodiments, various changes, arrangements and various equivalent substitutions of the embodiments are within the scope of the present application. Therefore, it should be understood that those skilled in the art can design a variety of systems and methods, which, although not explicitly shown or described herein, embody the principles of the present application and are therefore within the spirit and scope of the present application.

Claims

1. A video decoding method, characterized in that: The method comprises: Receiving, from an encoded video bitstream, encoded information of a current block in a current picture and adjacent blocks of the current block; Generate a merge candidate list of the current block according to the encoded information of the adjacent block, wherein the merge candidate list includes a non-adjacent motion vector MV prediction value; The non-adjacent MV prediction values ​​are divided into a plurality of subgroups, wherein: The first subset includes at least a plurality of non-adjacent spatial MV prediction values ​​located along an angle of π / 4 relative to the horizontal axis; The second subgroup includes at least a plurality of non-adjacent spatial MV prediction values ​​located along an angle of π / 2 relative to the horizontal axis; The third subgroup includes at least a plurality of non-adjacent temporal MV prediction values ​​located along an angle of 3π / 2 relative to the horizontal axis; For each non-neighboring MV prediction value, determine a template matching TM cost value of the non-neighboring MV prediction value based on a difference between a template of a sub-block in the current block and a sub-reference template of the non-neighboring MV prediction value, wherein the multiple sub-reference templates constitute a left reference template and a top reference template of a co-located block in a reference picture; Based on the TM cost value of each non-neighboring MV prediction value, within each subgroup, the plurality of non-neighboring MV prediction values ​​are sorted in ascending order; For each of the sorted subgroups, further performing: determining a TM cost value of each subgroup based on the TM cost value of each non-adjacent MV prediction value, and re-sorting the first subgroup, the second subgroup, and the third subgroup in ascending order based on the TM cost value of each subgroup; and, The current block is reconstructed according to the non-neighboring MV prediction values ​​selected from the sorted merge candidate list.

2. The method according to claim 1, characterized in that The determining of the TM cost value of each subgroup based on the TM cost value of each non-adjacent MV prediction value includes: The minimum TM cost value among the multiple TM cost values ​​in the sub-group is determined as the TM cost value of the sub-group.

3. The method according to claim 1, characterized in that The determining of the TM cost value of each subgroup based on the TM cost value of each non-adjacent MV prediction value includes: A median TM cost value of the plurality of TM cost values ​​in the subgroup is determined as the TM cost value of the subgroup.

4. The method according to claim 1, characterized in that: The determining of the TM cost value of each subgroup based on the TM cost value of each non-adjacent MV prediction value includes: A median TM cost value of a plurality of minimum TM cost values ​​among a plurality of TM cost values ​​in the sub-group is determined as the TM cost value of the sub-group.

5. The method according to claim 1, characterized in that: The determining of the TM cost value of each subgroup based on the TM cost value of each non-adjacent MV prediction value includes: The average of the first two smallest TM cost values ​​among the multiple TM cost values ​​in the sub-group is determined as the TM cost value of the sub-group.

6. A video encoding method, characterized in that: include: Setting information of a current block and adjacent blocks of the current block in a current picture; Generate a merge candidate list of the current block according to the information of the neighboring blocks, wherein the merge candidate list includes non-neighboring motion vector MV prediction values; The non-adjacent MV prediction values ​​are divided into a plurality of subgroups, wherein: The first subset includes at least a plurality of non-adjacent spatial MV prediction values ​​located along an angle of π / 4 relative to the horizontal axis; The second subgroup includes at least a plurality of non-adjacent spatial MV prediction values ​​located along an angle of π / 2 relative to the horizontal axis; The third subgroup includes at least a plurality of non-adjacent temporal MV prediction values ​​located along an angle of 3π / 2 relative to the horizontal axis; For each non-neighboring MV prediction value, determine a template matching TM cost value of the non-neighboring MV prediction value based on a difference between a template of a sub-block in the current block and a sub-reference template of the non-neighboring MV prediction value, wherein the multiple sub-reference templates constitute a left reference template and a top reference template of a co-located block in a reference picture; Based on the TM cost value of each non-neighboring MV prediction value, within each subgroup, the plurality of non-neighboring MV prediction values ​​are sorted in ascending order; For each of the sorted subgroups, further performing: determining a TM cost value of each subgroup based on the TM cost value of each non-adjacent MV prediction value, and re-sorting the first subgroup, the second subgroup, and the third subgroup in ascending order based on the TM cost value of each subgroup; and, The current block is encoded according to the non-neighboring MV prediction values ​​selected from the sorted merge candidate list.

7. A video decoding device, characterized in that: include: The processing circuit is configured to: Receiving, from an encoded video bitstream, encoded information of a current block in a current picture and adjacent blocks of the current block; Generate a merge candidate list of the current block according to the encoded information of the adjacent block, wherein the merge candidate list includes a non-adjacent motion vector MV prediction value; The non-adjacent MV prediction values ​​are divided into a plurality of subgroups, wherein: The first subset includes at least a plurality of non-adjacent spatial MV prediction values ​​located along an angle of π / 4 relative to the horizontal axis; The second subgroup includes at least a plurality of non-adjacent spatial MV prediction values ​​located along an angle of π / 2 relative to the horizontal axis; The third subgroup includes at least a plurality of non-adjacent temporal MV prediction values ​​located along an angle of 3π / 2 relative to the horizontal axis; For each non-neighboring MV prediction value, determine a template matching TM cost value of the non-neighboring MV prediction value based on a difference between a template of a sub-block in the current block and a sub-reference template of the non-neighboring MV prediction value, wherein the multiple sub-reference templates constitute a left reference template and a top reference template of a co-located block in a reference picture; Based on the TM cost value of each non-neighboring MV prediction value, within each subgroup, the plurality of non-neighboring MV prediction values ​​are sorted in ascending order; For each of the sorted subgroups, further performing: determining a TM cost value of each subgroup based on the TM cost value of each non-adjacent MV prediction value, and re-sorting the first subgroup, the second subgroup, and the third subgroup in ascending order based on the TM cost value of each subgroup; and, The current block is reconstructed according to the non-neighboring MV prediction values ​​selected from the sorted merge candidate list.

8. The device according to claim 7, characterized in that The processing circuit is configured to: The minimum TM cost value among the multiple TM cost values ​​in the sub-group is determined as the TM cost value of the sub-group.

9. The device according to claim 7, characterized in that The processing circuit is configured to: A median TM cost value of the plurality of TM cost values ​​in the subgroup is determined as the TM cost value of the subgroup.

10. A video encoding device, characterized in that: include: The processing circuit is configured to: Setting information of a current block and adjacent blocks of the current block in a current picture; Generate a merge candidate list of the current block according to the information of the neighboring blocks, wherein the merge candidate list includes non-neighboring motion vector MV prediction values; The non-adjacent MV prediction values ​​are divided into a plurality of subgroups, wherein: The first subset includes at least a plurality of non-adjacent spatial MV prediction values ​​located along an angle of π / 4 relative to the horizontal axis; The second subgroup includes at least a plurality of non-adjacent spatial MV prediction values ​​located along an angle of π / 2 relative to the horizontal axis; The third subgroup includes at least a plurality of non-adjacent temporal MV prediction values ​​located along an angle of 3π / 2 relative to the horizontal axis; For each non-neighboring MV prediction value, determine a template matching TM cost value of the non-neighboring MV prediction value based on a difference between a template of a sub-block in the current block and a sub-reference template of the non-neighboring MV prediction value, wherein the multiple sub-reference templates constitute a left reference template and a top reference template of a co-located block in a reference picture; Based on the TM cost value of each non-neighboring MV prediction value, within each subgroup, the plurality of non-neighboring MV prediction values ​​are sorted in ascending order; For each of the sorted subgroups, further performing: determining a TM cost value of each subgroup based on the TM cost value of each non-adjacent MV prediction value, and re-sorting the first subgroup, the second subgroup, and the third subgroup in ascending order based on the TM cost value of each subgroup; and, The current block is encoded according to the non-neighboring MV prediction values ​​selected from the sorted merge candidate list.

11. A method for processing a bit stream, characterized in that: The bit stream is stored on a non-volatile computer-readable storage medium, wherein the bit stream is decoded according to the video decoding method according to any one of claims 1 to 5, or the bit stream is generated by the video encoding method according to claim 6.

12. A non-volatile computer readable medium, characterized in that: Instructions are stored, and when the instructions are executed by a computer, the computer is caused to execute the method according to any one of claims 1 to 6.

13. A computer device, characterized in that: include: Processor and memory; The memory stores computer codes, and when the computer codes are executed by the processor, the processor executes the method according to any one of claims 1 to 6.

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