Video encoding and decoding method and device and storage medium

Abstract

According to one aspect of the present disclosure, a video decoding method is provided. In the method, encoded information of a current block of a video is received from an encoded video bitstream, the encoded information indicating that the current block is an intra block copy (IBC) block; the current block is divided into at least two partitions based on a geometric partition mode (GPM); deriving an intra prediction mode of a sub-block from one of the at least two partitions as an intra prediction mode of a pixel located at a position of a reference sub-block of a reference block, the reference sub-block corresponding to the sub-block of the current block, the position of the sub-block in the current block is the same as the position of the reference sub-block in the reference block, and the reference block is referenced by a block vector of the IBC block; storing the intra prediction mode of the sub-block of the current block; determining an adjacent block of the current block as an IBC block; and constructing a most probable mode (MPM) list for the neighboring block using the stored intra prediction mode.

Description

Incorporation by Reference

[0001] This application is a divisional application of Chinese patent application 202280005605.2 filed on September 6, 2022, which claims priority to U.S. Patent Application No. 17 / 901,547 filed on September 1, 2022, "ON PROPAGATING INTRA PREDICTION MODE INFORMATION OF IBC BLOCK BY USING BLOCK VECTOR", which claims priority to U.S. Provisional Application No. 63 / 261,251 filed on September 15, 2021, "On Propagating Intra Prediction Mode Information of IBC Block By Using BlockVector". The disclosures of these prior applications are incorporated herein by reference in their entirety. Technical Field

[0002] This disclosure describes embodiments generally related to video coding. Background Art

[0003] 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.

[0004] An uncompressed digital image and / or video may include a series of pictures, each picture having a spatial dimension of, for example, 20×1080 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), such as 60 pictures per second or 60 Hz. Uncompressed images and / or videos have specific bit rate requirements. For example, 1080p60 4:2:0 video (20x1080 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.

[0005] 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 of this article takes video encoding / decoding as an example, the same technology can be applied to the encoding / decoding of images in a similar manner without departing from the spirit of this application. 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 television distribution applications. The achievable compression ratio reflects that higher allowed / tolerable distortion can produce higher compression ratios.

[0006] Video encoders and decoders may utilize several broad categories of techniques including, for example: motion compensation, transform processing, quantization, and entropy coding and decoding.

[0007] Video coding techniques may include techniques known as intra-frame coding. In intra-frame coding, sample values ​​are represented without reference to samples or other data of previously reconstructed reference pictures. In some video codecs, pictures are spatially subdivided into sample blocks. When all sample blocks are encoded in intra-frame mode, the picture may be an intra-frame picture. Intra-frame pictures and their derivatives (e.g., independent decoder refresh pictures) may be used to reset the decoder state, and may therefore be used as the first picture in an encoded video bitstream and video session, or as a static image. Samples of intra-frame blocks may be used for transformation, and transform coefficients may be quantized before entropy coding and decoding. Intra-frame prediction may 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 needed to represent the block after entropy coding and decoding at a given quantization step size.

[0008] Traditional intra-frame coding, such as that used in MPEG-2 generation codecs, does 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 obtained during encoding and / or decoding of data blocks, where the surrounding sample data and / or metadata are obtained during spatially adjacent encoding / decoding and before the decoding order. This technique was later referred to as "intra-frame prediction" technology. It should be noted that, at least in some cases, intra-frame prediction only uses reference data in the picture currently being reconstructed, and does not use reference data from reference pictures.

[0009] Intra-frame prediction can take many different forms. When more than one such technique may be used in a given video coding technique, the particular technique used may be encoded in the particular intra-frame prediction mode that uses the particular technique. In some cases, an intra-frame prediction mode may have sub-modes and / or parameters, and these sub-modes and / or parameters may be encoded separately or contained in a mode codeword that defines the prediction mode used. Which codeword is used for a given mode / sub-mode / parameter combination can affect the coding efficiency gain through intra-frame prediction, and therefore the entropy coding and decoding technique used to convert the codeword into a bitstream.

[0010] H.264 introduced certain intra prediction modes, which were improved in H.265 and further improved in newer codecs such as the Joint Exploration Model (JEM), Versatile Video Coding (VVC), and Benchmark Set (BMS). A prediction block can be formed by using neighboring sample values ​​of samples that are already available. Sample values ​​of neighboring samples are copied into the prediction block in a certain direction. A reference to the direction used can be encoded in the bitstream, or can itself be predicted.

[0011] Reference Figure 1A , the lower right shows a set of eight known prediction directions among the 33 possible prediction directions defined by H.265 (corresponding to 33 angular modes in 35 internal modes). The point (101) where the arrows converge represents the sample being predicted. The arrows represent the direction based on which the sample is predicted. For example, arrow (102) indicates that sample (101) is predicted based on one or more samples at the upper right that are at an angle of 45 degrees to the horizontal direction. Similarly, arrow (103) indicates that sample (101) is predicted based on one or more samples at the lower left that are at an angle of 22.5 degrees to the horizontal direction.

[0012] 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 marked by "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, in block (104), sample S44 is the fourth sample 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. Further, reference samples following a similar numbering scheme are shown. The reference samples are marked 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.

[0013] Intra-picture prediction may be achieved by copying reference sample values ​​from neighboring samples indicated by a signaled prediction direction. For example, assume that the encoded video bitstream includes signaling for this block indicating a prediction direction consistent with arrow (102), i.e., predicting samples from the upper right sample at a 45 degree angle to the horizontal. In this case, samples S41, S32, S23, and S14 are predicted from the same R05. Sample S44 is then predicted from reference sample R08.

[0014] In some cases, to calculate a reference sample, especially when the direction is not divisible by 45 degrees, the values ​​of multiple reference samples may be combined, for example by interpolation.

[0015] As video coding technology has developed, the number of possible directions has increased. In H.264 (2003), nine different directions could be represented. In H.265 (2013), the number increased to 33. Currently, JEM / VVC / BMS, up to 65 directions can be supported. Experiments have been conducted to identify the most likely directions, and certain techniques in entropy coding and decoding are used to represent those possible directions with a small number of bits, accepting certain costs for less likely directions. In addition, the direction itself can sometimes be predicted based on the neighboring directions used in adjacent, already decoded blocks.

[0016] Figure 1B is a schematic diagram (110) depicting 65 intra prediction directions according to JEM to illustrate the increase in the number of prediction directions over time.

[0017] The mapping of the intra-prediction direction bits representing directions in the coded video bitstream may vary from one video coding technique to another. For example, the mapping may range from a simple direct mapping of codewords to a complex adaptive scheme including 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 occur than other directions. Since the goal of video compression is to reduce redundancy, in a well-functioning video coding technique, those unlikely directions will be represented using a larger number of bits than more likely directions.

[0018] Image and / or video encoding and decoding may be performed using inter-picture prediction with motion compensation. Motion compensation may be a lossy compression technique, and may involve a technique in which a block of sample data from a previously reconstructed picture or portion thereof (reference picture) is used to predict a newly reconstructed picture or picture portion 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 under reconstruction. The MV may have two dimensions, X and Y, or three dimensions, where the third dimension is an indication of the reference picture in use (the latter may indirectly be a temporal dimension).

[0019] In some video compression techniques, the MV applicable to a certain area of ​​sample data can be predicted from other MVs, such as those MVs related to another area of ​​sample data that is spatially adjacent to the area being reconstructed and that precede the MV in decoding order. Doing so can significantly reduce the amount of data required to encode the MV, thereby eliminating redundancy and increasing compression. MV prediction can work effectively, for example, because when encoding an input video signal derived from a camera (called natural video), there is a statistical likelihood that areas larger than the area to which a single MV can be applied move in similar directions, and therefore, in some cases, similar motion vectors derived from MVs of adjacent areas can be used for prediction. This results in the MV found for a given area being similar or identical to the MV predicted from the surrounding MVs, and after entropy coding and decoding, this can be represented with fewer bits than would be used if the MV were encoded directly. 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 bitstream). In other cases, MV prediction itself may be lossy, for example due to rounding errors when calculating predictors from several surrounding MVs.

[0020] Various MV prediction mechanisms are described in H.265 / HEVC (ITU-T Rec. H.265, "High Efficiency Video Coding", December 2016). Among the many MV prediction mechanisms provided by H.265, reference Figure 2 Described is a technique hereinafter referred to in the related art as "spatial merging".

[0021] refer to Figure 2, the current block (201) includes samples that have been discovered by the encoder during the motion search process that can be predicted from a previous block of the same size that has been spatially shifted. Instead of encoding the MV directly, the MV can be derived from metadata associated with one or more reference pictures, such as from the most recent (in decoding order) reference picture, using the MV associated with any of the five surrounding samples denoted A0, A1 and B0, B1, B2 (202 to 206, respectively). In H.265, MV prediction can use a predictor from the same reference picture that a neighboring block is using. Summary of the invention

[0022] Aspects of the present disclosure provide methods and apparatus for video encoding / decoding.In some examples, an apparatus for video decoding includes a processing circuit.

[0023] 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 of a video is received from an encoded video code stream, the encoded information indicating that the current block is an intra-block copy (IBC) block; the current block is divided into at least two partitions based on a geometric partition mode (GPM); the intra-prediction mode of a subblock from one of the at least two partitions is derived as an intra-prediction mode of a pixel located at a position of a reference subblock of a reference block, the reference subblock corresponds to the subblock of the current block, the position of the subblock in the current block is the same as the position of the reference subblock in the reference block, and the reference block is referenced by a block vector of the IBC block; the intra-prediction mode of the subblock of the current block is stored; a neighboring block of the current block is determined to be an IBC block; and a most probable mode (MPM) list is constructed for the neighboring block using the stored intra-prediction mode of the subblock of the current block.

[0024] According to another aspect of the present disclosure, a device is provided. The device includes a processing circuit. The processing circuit can be configured to perform any of the methods for video encoding / decoding.

[0025] Aspects of the present disclosure also provide a non-transitory computer-readable medium storing instructions, which, when executed by a computer for video decoding, cause the computer to perform any one of the methods for video encoding / decoding.

[0026] Aspects of the present disclosure further provide a computer storage medium on which a code stream formed by a computer program is stored. When the computer program is executed by a computer, the computer executes the video decoding method.

[0027] Aspects of the present disclosure also provide a non-volatile computer-readable storage medium storing instructions, characterized in that when the instructions are executed by at least one processor, the at least one processor executes the video encoding method, generates a video code stream and stores it. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Further features, properties and various advantages of the disclosed subject matter will become more apparent from the following detailed description and accompanying drawings, in which:

[0029] Figure 1A is a schematic illustration of an exemplary subset of intra-prediction modes.

[0030] Figure 1B is a diagram of exemplary intra prediction directions.

[0031] Figure 2 is a schematic illustration of a current block and its surrounding spatial merging candidates in an example.

[0032] Figure 3 is a schematic illustration of a simplified block diagram of a communication system (300) according to an embodiment.

[0033] Figure 4 is a schematic illustration of a simplified block diagram of a communication system (400) according to an embodiment.

[0034] Figure 5 is a schematic illustration of a simplified block diagram of a decoder according to an embodiment.

[0035] Figure 6 is a schematic illustration of a simplified block diagram of an encoder according to an embodiment.

[0036] Figure 7 A block diagram of an encoder according to another embodiment is shown.

[0037] Figure 8 A block diagram of a decoder according to another embodiment is shown.

[0038] Fig. 9 Exemplary positions of spatial merging candidates according to another embodiment are shown.

[0039] Fig.10 An exemplary redundancy check of spatial merging candidates is shown.

[0040] Fig.11 A schematic illustration of motion vector scaling for temporal merging candidates according to an embodiment is shown.

[0041] Fig.12 Exemplary candidate positions for temporal merging candidates according to an embodiment are shown.

[0042] Fig.13 An exemplary angular distribution of a geometric partitioning pattern (GPM) is shown according to an embodiment.

[0043] Fig.14 Exemplary partition lines of a GPM are shown, according to an embodiment.

[0044] Fig.15 An exemplary diagram of intra prediction modes propagating intra block copy (IBC) blocks is shown.

[0045] Fig.16 An exemplary diagram of propagating intra prediction modes for blocks encoded with IBC and intra modes in GPM is shown.

[0046] Fig.17 A flow chart outlining an exemplary decoding process according to some embodiments of the present disclosure is shown.

[0047] Fig.18 A flowchart outlining an exemplary encoding process according to some embodiments of the present disclosure is shown.

[0048] Fig.19 is a schematic illustration of a computer system according to an embodiment. DETAILED DESCRIPTION

[0049] Figure 3 3 is a simplified block diagram of a communication system (300) according to an embodiment disclosed in the present application. The communication system (300) includes a plurality of terminal devices, which can communicate with each other through, for example, a network (350). For example, the communication system (300) includes a first terminal device (310) and a second terminal device (320) interconnected through the network (350). Figure 3 In an embodiment of the present invention, the first terminal device (310) and the second terminal device (320) perform unidirectional data transmission. For example, the first terminal device (310) may encode video data (e.g., a video picture stream collected by the terminal device (310)) for transmission to the second 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 second 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.

[0050] In another embodiment, the communication system (300) includes a third terminal device (330) and a fourth terminal device (340) that perform bidirectional transmission of encoded video data, which can occur during a video conference, for example. For bidirectional data transmission, each of the third terminal device (330) and the fourth terminal device (340) can encode video data (e.g., a video picture stream collected by the terminal device) to transmit to the other terminal device of the third terminal device (330) and the fourth terminal device (340) through a network (350). Each of the third terminal device (330) and the fourth terminal device (340) can also receive the encoded video data transmitted by the other terminal device of the third terminal device (330) and the fourth terminal device (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.

[0051] exist Figure 3 In the embodiment of the present invention, the first terminal device (310), the second terminal device (320), the third terminal device (330) and the fourth terminal device (340) may be servers, personal computers and smart phones, 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 first terminal device (310), the second terminal device (320), the third terminal device (330) and the fourth terminal device (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 the present application, unless explained below, the architecture and topology of the network (350) may be irrelevant to the operation disclosed in the present application.

[0052] As an example, Figure 4 The video encoder and video decoder are shown in a streaming environment. The subject matter disclosed in this application is equally applicable to other video-enabled applications, including, for example, video conferencing, digital TV, storing compressed video on digital media including CDs, DVDs, memory sticks, etc.

[0053] 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 4 The client subsystem (406) and the client subsystem (408) in the video transmission system 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 transmission 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.

[0054] 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).

[0055] Figure 5is a block diagram of a video decoder (510) according to an embodiment disclosed in the present application. The video decoder (510) may be provided in an electronic device (530). The electronic device (530) may include a receiver (531) (e.g., a receiving circuit). The video decoder (510) may be used to replace Figure 4 A video decoder (410) of an embodiment.

[0056] The receiver (531) may receive one or more encoded video sequences to be decoded by the video decoder (510); in the same or another embodiment, one encoded video sequence is received at a time, wherein the decoding of each encoded video sequence is independent of the 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).

[0057] 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.

[0058] The parser (520) may perform entropy decoding / parsing operations on the video sequence received from the buffer memory (515), thereby creating symbols (521).

[0059] 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.

[0060] 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.

[0061] 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).

[0062] In some cases, the output samples of the scaler / inverse transform unit (551) may belong to an intra-coded block; that 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) generates surrounding blocks of the same size and shape as the block being reconstructed using reconstructed information extracted from a current picture buffer (558). 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.

[0063] 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.

[0064] 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 encoded video sequence (also referred to as the encoded video bitstream) and available to the loop filter unit (556) as symbols (521) from the parser (520). However, in other embodiments, the video compression techniques may also be responsive to meta-information obtained during decoding of a previous (in decoding order) portion of an encoded picture or encoded video sequence, as well as to previously reconstructed and loop filtered sample values.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] 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.

[0069] Figure 6 6 is a block diagram of a video encoder (603) according to an embodiment disclosed in the present application. The video encoder (603) is provided in an electronic device (620). The electronic device (620) includes a transmitter (640) (e.g., a transmission circuit). The video encoder (603) can be used to replace Figure 4 A video encoder (403) in an embodiment.

[0070] 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).

[0071] 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.

[0072] 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.

[0073] In some embodiments, the video encoder (603) operates in an encoding loop. As a simple description, in embodiments, the encoding 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 (because in the video compression technology considered in this application, any compression between the symbols and the encoded video code stream is lossless). 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, eg due to channel errors) is also used in some related techniques.

[0074] The operation of the "local" decoder (633) can be combined with the above Figure 5 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).

[0075] At this point, it can be observed that any decoder technology other than the parsing / entropy decoding present in the decoder must also be present in the corresponding encoder in substantially the same functional form. For this reason, the present application focuses on decoder operation. The description of encoder technology can be simplified because 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.

[0076] 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.

[0077] 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.

[0078] 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).

[0079] The controller (650) may manage encoding operations of the source encoder (630), including, for example, setting parameters and subgroup parameters for encoding video data.

[0080] 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.

[0081] 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).

[0082] 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:

[0083] 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.

[0084] 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.

[0085] 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.

[0086] 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.

[0087] 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.

[0088] 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.

[0089] 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 partitioned 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.

[0090] 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.

[0091] In addition, merge mode technology can be used in inter-picture prediction to improve coding efficiency.

[0092] 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.

[0093] Figure 7 is a diagram of a video encoder (703) according to another embodiment disclosed in the present application. The video encoder (703) is used to receive a processed block (e.g., a prediction block) of sample values ​​in a current video picture in a video picture sequence, 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 used to replace Figure 4A video encoder (403) in an embodiment.

[0094] 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.

[0095] 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.

[0096] 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.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] The entropy encoder (725) is used to format the code stream to produce an encoded block. The entropy encoder (725) generates various information 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 code stream. It should be noted that according to the disclosed subject matter, when the block is encoded in the inter-frame mode or the merge sub-mode of the bidirectional prediction mode, there is no residual information.

[0101] Figure 8FIG. 8 is a diagram of a video decoder (810) according to another embodiment disclosed in the present application. 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.

[0102] exist Figure 8 In one 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.

[0103] 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).

[0104] 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.

[0105] 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.

[0106] The residual decoder (873) is used to perform inverse quantization to extract dequantized transform coefficients, and process the dequantized transform coefficients to convert the residual 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).

[0107] 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.

[0108] It should be noted that the video encoders (403), (603) and (703) and the video decoders (410), (510) and (810) may be implemented using any suitable technology. In an embodiment, the video encoders (403), (603) and (703) and the video decoders (410), (510) and (810) may be implemented using one or more integrated circuits. In another embodiment, the video encoders (403), (603) and (703) and the video decoders (410), (510) and (810) may be implemented using one or more processors that execute software instructions.

[0109] The present disclosure includes embodiments directed to deriving and propagating intra prediction modes of intra block copied (IBC) blocks via block vectors (BVs) using reconstructed intra copied blocks.

[0110] ITU-T VCEG (Q6 / 16) and ISO / IEC MPEG (JTC 1 / SC 29 / WG 11) published the H.265 / HEVC (High Efficiency Video Codec) standard in 2013 (version 1), 2014 (version 2), 2015 (version 3), and 2016 (version 4). In 2015, the two standards organizations jointly formed the JVET (Joint Video Exploration Team) to explore the potential of developing the next video codec standard beyond HEVC. In October 2017, the two standards organizations issued a Joint Call for Proposals on Video Compression with Capability beyond HEVC (CfP). 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 the 360 ​​video category were submitted. In April 2018, all CfP responses received were evaluated at the 122nd MPEG / 10th JVET meeting. As a result of this meeting, JVET officially launched the standardization process for the next generation video codec beyond HEVC, the new standard was named Versatile Video Codec (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) published the VVC video codec standard (version 1).

[0111] In inter prediction, for each inter-predicted codec unit (CU), the codec feature of VVC requires motion parameters, such as for the generation of samples for inter prediction. Motion parameters may include motion vectors, reference picture indexes, reference picture list usage indexes, 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 significant residual coefficients, encoded motion vector increments, and / or reference picture indexes may not be required. When a CU is encoded in merge mode, the motion parameters of the CU may be obtained from neighboring CUs. Neighboring CUs may include spatial candidates and temporal candidates, as well as additional scheduling (or additional candidates) such as those introduced in VVC. Merge mode may be applied to any inter-predicted CU, not just to skip mode. An alternative to merge mode is explicit transmission of motion parameters, where motion vectors, corresponding reference picture indexes for each reference picture list, reference picture list usage flags, and / or other required information may be explicitly signaled per CU.

[0112] In VVC, the VVC Test Model (VTM) reference software may include a number of new and revised inter-frame prediction codec tools, which may include one or more of the following: (1) Extended combined forecast; (2) Merged Motion Vector Difference (MMVD) (3) AMVP mode with symmetric MVD signaling (4) Prediction of affine motion compensation (5) Sub-block based temporal motion vector prediction (SbTMVP) (6) Adaptive Motion Vector Resolution (AMVR) (7) Sports field storage: 1 / 16 th Luma sample MV storage and 8×8 motion field compression (8) Bidirectional prediction with CU-level weights (BCW) (9) Bidirectional Optical Flow (BDOF) (10) Decoder-side motion vector correction (DMVR) (11) Combined Inter and Intra Prediction (CIIP) (12) Geometric Partitioning Model (GPM)

[0113] The merge candidate list may be constructed by including five types of candidates, such as in VTM 4. The merge candidate list may be constructed in the following order: 1) Spatial MVP from spatially neighboring CUs, 2) Time MVP from the same CU, 3) History-based MVP from FIFO table, 4) Average MVP of pairs, and 5) Zero MV.

[0114] The size of the merge list may be signaled in the slice header. The maximum allowed size of the merge list may be 6, such as in VTM 4. For each CU coded 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 the other bins may use bypass encoding and decoding.

[0115] In spatial candidate derivation, such as in VVC, the derivation of spatial merge candidates may be the same or similar to the derivation of spatial merge candidates in HEVC. Fig. 9 The maximum number of merge candidates (eg, four merge candidates) is selected from the candidates in the illustrated positions. Fig. 9 As shown, the current block (901) may include 0 , A1 , B 0 , B 1 and B 2 The order of deriving spatial merging candidates may be B 1 , A 1 , B 0 , A 0 and B 2 . Only when position A 0 , B 0 , B 1 or A 1 Position B is considered only when any CU (or block) at position B is unavailable (for example, because the CU belongs to another slice or tile) or is already intra-coded. 2 . At add position A 1 After selecting the candidates (or blocks) at the end, the remaining candidates (or blocks) can be added for redundancy check. Redundancy check can ensure that candidates with the same motion information are excluded from the merge list, thereby improving the encoding and decoding efficiency. In order to reduce the computational complexity, redundancy check can not consider all possible candidate pairs. Instead, only Fig.10 For example, redundancy check can be applied to 5 candidate pairs, such as A 1 and B 1 The candidate pairs and A 1 and A 0 Candidate pairs. 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, only if the corresponding candidate B 1 When the same motion information is not included, candidate B 0 can be added to the merge list.

[0116] In temporal candidate derivation, only one candidate can be added to the merge list. Fig.11 As shown, when deriving temporal merge candidates for the current CU (1114), the 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.11As illustrated by the dashed line (1102) in FIG. 1 , a scaled motion vector for a temporal merge candidate may be obtained, which 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 (e.g., Curr_ref) (1106) of the current picture and the current picture (e.g., Curr_pic) (1108). td may be defined as the POC difference between the reference picture (e.g., Col_ref) (1110) of the co-located picture 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.

[0117] Candidate C 0 With C 1 Select the location of the time candidate between Fig.12 For example, if position C 0 If the CU at position C is not available, is intra-coded, or is outside the current row of the CTU, then position C can be used 1 Otherwise, position C can be used in the derivation of temporal merge candidates. 0 .

[0118] GPM can be applied to inter prediction. GPM can be applied only to CUs of certain sizes, such as CUs with a size of 8×8 or larger. GPM can be signaled, for example, using a CU-level flag and acts as a merge mode. Other merge modes may include a normal merge mode, an MMVD mode, a CIIP mode, and / or a sub-block merge mode.

[0119] When using GPM, the CU can be divided into two geometric partitions using one of multiple partitioning methods. The partitioning methods can be distinguished by angles and edges. In an embodiment, 64 different partitioning methods can be applied in GPM. The 64 different partitioning methods can be distinguished by 24 angles relative to the center of the CU (these angles are non-uniformly quantized between 0° and 360°) and up to 4 edges. Fig.13 Twenty-four exemplary angles applied in the GPM are shown. Fig.14Four exemplary possible partition edges associated with an angle indexed as 3 in the CU (1402) are shown, where each of the partition edges can be associated with a corresponding distance index. The distance index can indicate a distance relative to the center of the CU (1402). In GPM, each geometric partition in the CU can be inter-predicted using a corresponding motion vector. In addition, only single prediction is allowed for each partition. For example, each partition can have one motion vector and one reference index. The constraint of allowing only single-prediction motion for each partition can ensure that only two motion-compensated predictions are required for each CU, which also applies to traditional dual prediction.

[0120] If GPM is used for the current CU, a signal indicating a geometric partition index and two merge indexes (one for each partition) may be further signaled. The maximum GPM candidate size may be signaled, for example, explicitly signaled at the slice level. The maximum GPM candidate size may specify a syntactic binarization of the GPM merge index. After predicting each of the two geometric partitions, a blending process with adaptive weights may be used to adjust sample values ​​along the edges of the geometric partitions. Thus, a prediction signal for the entire CU may be generated after the blending process. Transform and quantization processes may be further applied to the entire CU in other prediction modes. Further, the motion field of the CU predicted using GPM may be stored.

[0121] The implementation cost of IBC may be high for the entire reconstructed area of ​​the current picture. For example, a disadvantage of the IBC concept in HEVC is that additional memory is required in the decoded picture buffer (DPB). Therefore, external memory is usually used in the hardware implementation of IBC. Additional external memory access may be accompanied by increased memory bandwidth.

[0122] In some embodiments, it may be necessary to reduce implementation costs. For example, VVC can use fixed memory, which can significantly reduce memory bandwidth requirements and hardware complexity by implementing IBC using on-chip memory. In addition, the block vector (BV) encoding and decoding of IBC can adopt the concept of merged lists for inter-frame prediction. The IBC list construction process can consider the BVs of two spatial neighbors and five history-based BVs (HBVPs), where the first HBVP is compared with the spatial candidates (e.g., the BVs of two spatial candidates) only when the first HBVP is added to the candidate list (or IBC list).

[0123] To further improve compression efficiency, such as in VVC, template matching (TM) with motion correction at the decoder side can be used. In TM mode, motion is corrected by constructing a template from adjacent reconstructed samples on the left and above, and the closest match between the template in the current picture and the reference frame can be determined.

[0124] TM can be applied to GPM. When encoding a CU in GPM, it can be determined whether to apply TM to correct each motion of the geometric partition. When TM is selected, the template can be constructed using the neighboring samples on the left and above, and the motion can be further corrected by finding the best match between the current template and the reference area with the same template pattern in the reference frame. The corrected motion can be used to perform motion compensation for the geometric partition and can be further stored in the motion field.

[0125] GPM can be applied to support inter-frame and intra-frame prediction to enhance codec performance beyond VVC. For example, in addition to the motion vectors from the merge candidate list of each geometric partition in the CU to which GPM is applied, a predefined intra-frame prediction mode can also be selected for (or about) the geometric partition line. The intra-frame prediction mode or the inter-frame prediction mode can be determined for each geometric partition based on a flag. When inter-frame prediction is selected, a single prediction signal can be generated by the MV from the merge candidate list. Otherwise, if the intra-frame prediction mode is selected, a single prediction signal can be generated from adjacent samples, which are predicted from the specified index of the intra-frame prediction mode. The possible changes in the intra-frame prediction mode can be restricted by the geometric shape. Finally, the two single prediction signals can be mixed in the same way as ordinary GPM.

[0126] In order to reduce complexity and signaling overhead, changes in possible intra-frame prediction modes can be studied (or defined). For example, the impact of changes in possible intra-frame prediction modes on a GPM with inter-frame and intra-frame prediction is studied for two exemplary configurations. The first configuration only tries parallel and perpendicular intra-directional modes for (or about) geometric partition lines. In addition to parallel and perpendicular intra-angular modes for (or about) geometric partition lines, planar modes are also tested in the second configuration. Two or three possible intra-frame prediction modes are tested for geometric partitions in a GPM with inter-frame and intra-frame prediction.

[0127] In template-based intra mode derivation (TIMD), such as in JVET-V0098, for each intra mode in the MPM, the sum of absolute transform differences (SATD) between the prediction and reconstructed samples of the template area of ​​the current CU can be calculated, and the intra mode with the minimum SATD cost can be selected for the current CU. In contrast to selecting only one intra mode with the minimum SATD cost, such as in JVET-W0123, the first two modes with the minimum SATD cost derived by TIMD can also be selected for the current CU. The two selected modes can further use weight fusion, and the weighted intra prediction can be used as the intra predictor of the current CU. Among the two selected modes, if the cost of the selected intra mode with the minimum SATD cost is greater than half the cost of the other selected intra mode, fusion can be applied. Otherwise, only the intra mode with the minimum SATD cost can be selected. If fusion is applied, weight values ​​can be derived from the SATD costs of the two modes.

[0128] During the generation of the MPM list, if the adjacent CU is encoded as an inter CU (i.e., the CU is encoded in an inter prediction mode), the intra prediction mode of the adjacent CU may be derived as a planar mode by default. In order to improve the accuracy of the MPM list, an intra mode propagation method for inter CUs may be applied in the construction of the MPM list. For example, in JVET-V0098, the intra prediction mode of the inter CU may be propagated via the motion vector and reference picture associated with the inter CU, and the propagated intra prediction mode of the inter CU may be used in the construction of the MPM list. It should be noted that the intra mode propagation of the inter CU may only be applied to the derivation of the TIMD mode.

[0129] In order to improve the accuracy of MPM list construction, the propagated intra mode of the adjacent inter CU can be used for TIMD mode. The propagated intra mode of the adjacent inter CU can be derived from the motion vector and reference picture of the adjacent inter CU. However, when the adjacent CU is encoded as IBC prediction mode, the plane mode can still be used for MPM list construction.

[0130] In the present disclosure, the intra prediction mode can be derived by using the block vector (BV) of IBC, and the intra prediction mode information can be stored for the purpose of intra mode propagation. For example, when the current block is predicted by IBC, the propagated intra mode of the current block can be derived from the intra mode of the reference block of the current block. The reference block can be indicated (or referenced) by the BV of IBC. When the neighboring block of the current block is an IBC block (or predicted by IBC), the propagated intra mode of the current block can be used to construct the MPM list of the neighboring block. Therefore, when the neighboring block is encoded with IBC, the intra prediction mode of the reference block of the current block can be a candidate for the construction of the MPM list of the neighboring block.

[0131] In an embodiment, the propagated intra-mode may be stored for the smallest block (also referred to as the smallest sub-block or sub-block) of the current block that has been IBC-coded, such as in a 4×4 luma block (or sub-block) of the current block. Thus, the corresponding propagated intra-mode of each sub-block of the current block may be stored. The propagated intra-mode of the current block may be derived from the intra-mode of a reference block of the current block. The reference block may be indicated (or referenced) by the BV of the IBC.

[0132] In an embodiment, the intra mode information of an IBC block (or a block predicted by IBC) may be propagated from a reference block pointed to by the BV of the IBC. Fig.15 An exemplary diagram of intra prediction mode propagation via an IBC block of a BV is shown. Fig.15 As shown, a BV (1502) can be applied to an IBC block (or current block) (1504) to locate a reference block (1506) of the current block (1504) in a reconstructed picture (not shown). In order to obtain an intra-frame prediction mode from the reference block (1506), the reference block (1506) pointed to by the BV (1502) can be divided into multiple minimum units (or sub-blocks), such as 4×4 units. For each minimum unit in the reference block (1506), for example (1508), a corresponding intra-frame prediction mode can be derived from a sample located in the corresponding minimum unit (or corresponding sub-block). The sample can be located at a center position or a corner position of the minimum unit (or sub-block). For example, the sample can be an upper left sample of the minimum unit. When the reference block is encoded, the intra-frame prediction mode of the minimum unit of the reference block can be further stored. The stored intra prediction mode of the minimum unit of the reference block (1506) may be propagated to the current block (1504), and the reference block (1506) may be a co-located CU of the current block (1504).

[0133] Still refer to Fig.15In some embodiments, the current block (1504) may be divided into a plurality of sub-blocks (e.g., (1510)). Each of the plurality of sub-blocks may have the same size as the minimum unit of the reference block (1506). Therefore, each of the sub-blocks of the current block (1504) may have a corresponding minimum unit in the reference block (1506). The position of the sub-blocks in the current block may be the same as the position of the corresponding minimum unit (or sub-block) in the reference block. For example, the sub-block (1510) is at the first row and third column of the current block (1504), and the minimum unit (1508) is at the first row and third column of the reference block (1506). Therefore, the sub-block (1510) of the current block (1504) may correspond to the minimum unit (1508) in the reference block (1506). Therefore, each of the sub-blocks of the current block (1504) may have a corresponding propagated intra-mode derived from the minimum unit corresponding to the corresponding sub-block in the reference block (1506). For example, the sub-block (1510) may have a propagated intra-mode that may be derived from the intra-mode of the minimum unit (1508) in the reference block (1506).

[0134] It should be noted that an intra prediction mode (IPM) map (1512) may be formed based on a reconstructed picture (not shown). The IMP map (1512) may include a plurality of sub-regions (e.g., (1514)). Each of the sub-regions may correspond to a respective intra mode associated with the reconstructed picture (not shown).

[0135] In an embodiment, the center position of each minimum unit (e.g., 4×4 unit) within the reference block (1506) may be applied to derive the co-located corresponding intra-frame prediction mode of the current block (1504). Therefore, the intra-frame prediction mode of the sub-block (e.g., (1510)) in the current block (1504) may be determined as the intra-frame mode of the pixel (or sample) located at the center position of the minimum unit (e.g., (1508)) corresponding to the sub-block of the reference block (1506). The center position of the minimum unit (or 4×4 unit) may be at one of the second row and second column of the minimum unit, the second row and third column of the minimum unit, the third row and second column of the minimum unit, or the third row and third column of the minimum unit. Exemplary illustrations of the center position may be shown in FIG. Fig.15, as shown in the minimum unit (1508) of . As shown in the minimum unit (1508), the center position can be one of the positions marked as (1, 1), (1, 2), (2, 1) or (2, 2). The position marked as (1, 1) can correspond to the center position at the second row and the second column of the minimum unit (1508). The position marked as (2, 1) can correspond to the center position at the second row and the third column of the minimum unit (1508). The position marked as (1, 2) can correspond to the center position at the third row and the second column of the minimum unit (1508). The position marked as (2, 2) can correspond to the center position at the third row and the third column of the minimum unit (1508). Therefore, the propagated intra-frame prediction mode of the sub-block (1510) can be derived from the intra-frame prediction mode of the pixel at the center position of the minimum unit (1508).

[0136] In an embodiment, the corner position (such as the upper left, upper right, lower left or lower right position) of each minimum unit (or 4×4 unit) (1508) may be applied to derive the co-located corresponding intra prediction mode. Fig.15 As shown, the upper left position may be labeled as (0, 0), the upper right position may be labeled as (3, 0), the lower left position may be labeled as (0, 3), and the lower right position may be labeled as (3, 3). Therefore, the propagated intra-prediction mode of the sub-block (1510) may be derived from the intra-prediction mode of the pixel at one of the corner positions of the minimum unit (1508).

[0137] In an embodiment, when a coded CU (or current block) is coded with IBC and intra mode in GPM, the intra prediction mode of the reference block may be propagated only to the sub-blocks of the current block within the geometric partition with IBC mode. Fig.16 As shown, the current block (1604) can be partitioned into a first partition (1614) and a second partition (1616) by GPM. The first partition (1614) can be predicted by intra prediction, and the second partition (1616) can be predicted by IBC. Therefore, the intra prediction mode of the reference block (1606) of the current block (1604) can be propagated only to the sub-blocks of the second partition (1616). Therefore, the intra mode of the minimum unit (1608) in the reference block (1606) can be propagated to the corresponding sub-block (1610) of the second partition (1616) in the current block (1604). The intra mode of the minimum unit (1612) in the reference block (1606) may not be propagated to the corresponding sub-block (1618) of the first partition (1614) in the current block (1604).

[0138] Fig.17 A flow chart outlining an exemplary decoding process (1700) according to some embodiments of the present disclosure is shown. Fig.18A 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 (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.

[0139] 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.

[0140] The process (e.g., (1700) and (1800)) can be used in the reconstruction and / or encoding of the block 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 function of a video encoder (403), a processing circuit that performs the function of a video decoder (410), a processing circuit that performs the function of a video decoder (510), a processing circuit that performs the function of a video encoder (603), and the like. 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)).

[0141] like Fig.17 As shown, the process (1700) may start at (S1701) and proceed to (S1710). At (S1710), encoded information of a current block in a current picture of a video may be received from an encoded video code stream. The encoded information may indicate that the current block is an IBC block.

[0142] At (1720), an intra prediction mode of a subblock of the current block may be derived based on a reference subblock in a reference block. The reference subblock may correspond to a subblock of the current block and may be pointed to by a block vector of an IBC block.

[0143] At (1730), the intra prediction modes of the sub-blocks of the current block may be further stored.

[0144] At (1740), it may be determined that a neighboring block of the current block is an IBC block.

[0145] At (1750), an MPM list may be constructed for neighboring blocks of the current block using the stored intra prediction modes.

[0146] The intra prediction mode of the subblock may be derived as an intra mode of a pixel located at a center position of the reference subblock of the reference block, where the center position may be at a second row and a second column of the reference subblock.

[0147] The intra prediction mode of the subblock may be derived as an intra mode of a pixel located at a center position of the reference subblock of the reference block, where the center position may be at a second row and a third column of the reference subblock.

[0148] The intra prediction mode of the subblock may be derived as an intra mode of a pixel located at a center position of the reference subblock of the reference block, where the center position may be at a third row and a second column of the reference subblock.

[0149] The intra prediction mode of the subblock may be derived as an intra mode of a pixel located at a center position of a reference subblock of the reference block, where the center position may be at a third row and a third column of the reference subblock.

[0150] The intra prediction mode of the subblock may be derived as an intra mode of a pixel located at one of an upper right position, an upper left position, a lower left position, or a lower right position of the reference subblock of the reference block.

[0151] In some embodiments, the current block may be partitioned into a first partition and a second partition based on a geometric partition mode (GPM). The first partition may be predicted by IBC, and the second partition may be predicted by intra prediction. The sub-block may be located in the first partition predicted by IBC.

[0152] In some embodiments, the sub-blocks of the current block may be 4×4 pixel units.

[0153] In some embodiments, the intra prediction mode of the sub-block may be determined as a candidate prediction mode in an MPM list of a neighboring block of the current block, where the neighboring block may be predicted by IBC.

[0154] After (S1750), the process proceeds to (S1799) and terminates.

[0155] The process (1700) may be varied as appropriate. One or more steps in the process (1700) may be modified and / or omitted. One or more additional steps may be added. Any suitable order of implementation may be used.

[0156] like Fig.18As shown, the process (1800) may start at (S1801) and proceed to (S1810). At (S1810), an intra prediction mode of a subblock of a current block in a current picture may be derived based on a reference subblock in a reference block. The reference subblock may correspond to a subblock of the current block. The current block may be an IBC block. The reference block may be pointed to by a block vector of the IBC block.

[0157] At (S1820), the intra prediction modes of the subblocks of the current block may be stored.

[0158] At (S1830), it may be determined that a neighboring block of the current block is an IBC block.

[0159] At (S1840), an MPM list may be constructed for neighboring blocks of the current block using the stored intra prediction modes.

[0160] At (S1850), codec information of the current block may be generated. The codec information may indicate that the current block is predicted by IBC, and that intra prediction information of a subblock of the current block is based on a corresponding reference subblock of a reference block of the current block.

[0161] The process then proceeds to (S1899) and terminates.

[0162] The process (1800) may be varied as appropriate. One or more steps in the process (1800) may be modified and / or omitted. One or more additional steps may be added. Any suitable order of implementation may be used.

[0163] 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 system (1900) is shown that is suitable for implementing certain embodiments of the disclosed subject matter.

[0164] 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.

[0165] 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.

[0166] Fig.19The components shown for the computer system (1900) are exemplary in nature and are not intended to limit the scope of use or functionality of the computer software implementing the 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 system (1900).

[0167] The computer system (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 devices 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).

[0168] 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).

[0169] The computer system (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 can 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).

[0170] The computer system (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) or similar media (1921) including CD / DVD, a thumb drive (1922), a removable hard drive or solid state drive (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.

[0171] 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.

[0172] The computer system (1900) may also include an interface to one or more communication networks. For example, 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. The network also includes 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 ports or peripheral buses (1949) (e.g., a USB port of the computer system (1900)); other systems are typically integrated into the core of the computer system (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 system (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.

[0173] The above-mentioned human-machine interface devices, human-accessible storage devices, and network interfaces may be connected to the core (1940) of the computer system (1900).

[0174] 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.

[0175] 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.

[0176] 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.

[0177] 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. Appendix A: Acronyms JEM: Joint Exploration Model VVC: versatile video coding BMS: Benchmark set MV: Motion Vector HEVC: High Efficiency Video Coding SEI: Supplementary Enhancement Information VUI: Video Usability Information GOPs: Groups of Pictures TUs: Transform Units PUs: Prediction Units CTUs: Coding Tree Units CTBs: Coding Tree Blocks PBs: Prediction Blocks HRD: Hypothetical Reference Decoder SNR: Signal Noise Ratio CPUs: Central Processing Units GPUs: Graphics Processing Units CRT: Cathode Ray Tube LCD: Liquid-Crystal Display OLED: Organic Light-Emitting Diode CD: Compact Disc DVD: Digital Video Disc ROM: Read-Only Memory RAM: Random Access Memory ASIC: Application-Specific Integrated Circuit PLD: Programmable Logic Device LAN: Local Area Network GSM: Global System for Mobile communications LTE: Long-Term Evolution CANBus: Controller Area Network Bus USB: Universal Serial Bus PCI: Peripheral Component Interconnect FPGA: Field Programmable Gate Areas SSD: solid-state drive IC:Integrated Circuit CU: Coding Unit

[0178] 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 encoded information of a current block in a current picture of a video from an encoded video code stream, wherein the encoded information indicates that the current block is an intra-block copy (IBC) block; the current block is divided into at least two partitions based on a geometric partition mode (GPM); deriving an intra prediction mode of a subblock from one of the at least two partitions as an intra prediction mode of a pixel located at a position of a reference subblock of a reference block, the reference subblock corresponding to the subblock of the current block, the position of the subblock in the current block being the same as the position of the reference subblock in the reference block, the reference block being referenced by a block vector of the IBC block; storing the intra prediction mode of the subblock of the current block; Determining that an adjacent block of the current block is an IBC block; and A most probable mode (MPM) list is constructed for the neighboring block using the stored intra prediction mode of the subblock of the current block.

2. The method according to claim 1, characterized in that The sub-block of the current block is a 4×4 pixel unit.

3. The method according to claim 1, characterized in that The method further comprises: The intra prediction mode of the subblock is indicated as a candidate prediction mode in the MPM list of the neighboring block of the current block, the neighboring block being predicted by the IBC.

4. The method according to any one of claims 1 to 3, characterized in that: The position is a center position at any of the following: (i) the second row and the second column of the reference sub-block; (ii) the second row and the third column of the reference sub-block; (iii) the third row and the second column of the reference sub-block; and (iv) the third row and the third column of the reference sub-block.

5. The method according to any one of claims 1 to 3, characterized in that: The sub-block of the current block is a 4×4 luminance block.

6. The method according to any one of claims 1 to 3, characterized in that: The at least two partitions include a first partition and a second partition, the first partition is predicted by IBC, and the second partition is predicted by intra prediction; the subblock is located in the first partition predicted by the IBC.

7. The method according to any one of claims 1 to 3, characterized in that: The reference block is located in a geometric partition of the current block.

8. A video encoding method, characterized in that: The method comprises: determining an intra prediction mode of a subblock of a current block as an intra prediction mode of a pixel located at a position of a reference subblock of a reference block, the reference subblock corresponding to the subblock of the current block, the position of the subblock in the current block being the same as the position of the reference subblock in the reference block, the reference block being referenced by a block vector of an IBC block; the current block being divided into at least two partitions based on a geometric partition mode (GPM); Determine that an adjacent block of the current block is an IBC block; constructing a most probable mode (MPM) list for the neighboring block using the intra prediction mode of the subblock of the current block; and The sub-block of the current block is encoded based on the MPM list.

9. The method according to claim 8, characterized in that The sub-block of the current block is a 4×4 pixel unit.

10. The method according to claim 8, characterized in that The method further comprises: The intra prediction mode of the subblock is indicated as a candidate prediction mode in the MPM list of the neighboring block of the current block, the neighboring block being predicted by the IBC.

11. The method according to any one of claims 8 to 10, characterized in that: The position is a center position at any of the following: (i) the second row and the second column of the reference sub-block; (ii) the second row and the third column of the reference sub-block; (iii) the third row and the second column of the reference sub-block; and (iv) the third row and the third column of the reference sub-block.

12. The method according to any one of claims 8 to 10, characterized in that: The at least two partitions include a first partition and a second partition, the first partition is predicted by IBC, and the second partition is predicted by intra prediction; the subblock is located in the first partition predicted by the IBC.

13. The method according to any one of claims 8 to 10, characterized in that The reference block is located in a geometric partition of the current block.

14. A video encoding and decoding device, characterized in that: include: processor and memory, The memory is used to store program instructions; The processor is used to call the program instructions stored in the memory to implement the method according to any one of claims 1 to 13.

15. A computer storage medium, characterized in that A code stream formed by a computer program is stored thereon, and when the computer program is executed by a computer, the computer executes the video decoding method according to any one of claims 1 to 7.

16. A non-volatile computer-readable storage medium storing instructions, characterized in that: When the instruction is executed by at least one processor, the at least one processor executes the video encoding method according to any one of claims 8 to 13 to generate and store a video code stream.

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