CN111726630B

CN111726630B - Processing method and device based on triangular prediction unit mode

Info

Publication number: CN111726630B
Application number: CN201910305953.1A
Authority: CN
Inventors: 杨海涛; 张恋
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2019-03-18
Filing date: 2019-04-16
Publication date: 2024-03-15
Anticipated expiration: 2039-04-16
Also published as: CN111726630A

Abstract

The application provides a processing method and device based on a triangular prediction unit mode, wherein the method comprises the following steps: analyzing a code stream to obtain a first prediction parameter, wherein the first prediction parameter is used for processing a preset video processing unit; determining whether to allow processing of a plurality of coding units CU in the preset video processing unit by using a triangular prediction unit mode TPM according to the first prediction parameters, wherein the plurality of CUs comprise CUs to be processed; and when the TPM is forbidden to process the plurality of CUs in the preset video processing unit, the TPM is forbidden to process the CUs to be processed. By implementing the method and the device, the complexity of encoding and decoding can be reduced, and the encoding and decoding efficiency can be improved.

Description

Processing method and device based on triangular prediction unit mode

Technical Field

The present disclosure relates to the field of video image processing technologies, and in particular, to a processing method and apparatus based on a triangular prediction unit mode.

Background

Digital video capabilities can be incorporated into a wide variety of devices, including digital televisions, digital direct broadcast systems, wireless broadcast systems, personal Digital Assistants (PDAs), laptop or desktop computers, tablet computers, electronic book readers, digital cameras, digital recording devices, digital media players, video gaming devices, video game consoles, cellular or satellite radio telephones (so-called "smartphones"), video teleconferencing devices, video streaming devices, and the like. Digital video devices implement video compression techniques such as those described in the standards defined by MPEG-2, MPEG-4, ITU-T H.263, ITU-T H.264/MPEG-4 part 10 Advanced Video Coding (AVC), the video coding standard H.265/High Efficiency Video Coding (HEVC) standard, and extensions of such standards. Video devices may more efficiently transmit, receive, encode, decode, and/or store digital video information by implementing such video compression techniques.

Video compression techniques perform spatial (intra-picture) prediction and/or temporal (inter-picture) prediction to reduce or eliminate redundancy inherent in video sequences. For block-based video coding, a video slice (i.e., a video frame or a portion of a video frame) may be partitioned into tiles, which may also be referred to as treeblocks, coding Units (CUs), and/or coding nodes. Image blocks in a slice to be intra-coded (I) of an image are encoded using spatial prediction with respect to reference samples in neighboring blocks in the same image. Image blocks in a to-be-inter-coded (P or B) stripe of an image may use spatial prediction with respect to reference samples in neighboring blocks in the same image or temporal prediction with respect to reference samples in other reference images. An image may be referred to as a frame and a reference image may be referred to as a reference frame.

The fusion (merge) technique is an inter prediction technique, and determines motion information with minimum rate-distortion (RD) cost in a list as a motion vector predictor (motion vector predictor, MVP) of a current block by constructing a candidate motion vector list. The triangulation unit mode (triangle prediction unit mode, TPM) is a technique for inter prediction using a triangulation unit in the merge technique. However, the TPM must determine at the CU level (i.e., for each CU of the image frame) whether to use TPM techniques, resulting in higher complexity of encoding and decoding and, in some cases, lower encoding efficiency.

Disclosure of Invention

The application provides a processing method and device based on a triangular prediction unit mode, which can reduce the complexity of editing codes to a certain extent and improve the coding and decoding efficiency.

In a first aspect, the present application provides a processing method for a triangular prediction unit mode, including: analyzing a code stream to obtain a first prediction parameter, wherein the first prediction parameter is used for processing a preset video processing unit; determining whether to allow processing of a plurality of coding units CU in the preset video processing unit by using a triangular prediction unit mode TPM according to the first prediction parameters, wherein the plurality of CUs comprise CUs to be processed; and when the TPM is forbidden to process the plurality of CUs in the preset video processing unit, the TPM is forbidden to process the CUs to be processed.

In this application example, when determining that processing at a sequence level, an image level, or a tile group level is prohibited from using a TPM to process a plurality of CUs in a preset video image unit according to the maximum number of candidate motion vector lists, it may be directly determined that processing of a CU to be processed in the plurality of CUs is prohibited from using the TPM, thereby reducing complexity of encoding and decoding, and improving encoding and decoding efficiency.

In a possible implementation, the preset video processing unit includes a slice group, a frame of image or a video sequence.

In one possible implementation, when processing is allowed for a plurality of CUs in the preset video processing unit using a TPM, the method further includes: analyzing the code stream to obtain a second prediction parameter, wherein the second prediction parameter is used for processing the CU to be processed; and determining whether to use the TPM to process the CU to be processed according to the second prediction parameters.

In a possible implementation manner, the determining, according to the first prediction parameter, whether to allow processing of the plurality of CUs in the preset video processing unit using the TPM includes: when the value of the first prediction parameter is a first value, determining that the TPM is allowed to process a plurality of CUs in the preset video processing unit; and when the value of the first prediction parameter is a second value, determining to prohibit processing of a plurality of CUs in the preset video processing unit by using a TPM, wherein the first value is different from the second value.

In a possible implementation manner, the first prediction parameter is a maximum number of candidate motion vector lists corresponding to the preset video processing unit, and the determining, according to the first prediction parameter, whether to allow processing of the multiple CUs in the preset video processing unit using the TPM includes: comparing the maximum number with a first threshold; when the maximum number is greater than or equal to the first threshold, determining that the TPM is allowed to process a plurality of CUs in the preset video processing unit; and when the maximum number is smaller than the first threshold value, determining to prohibit processing of a plurality of CUs in the preset video processing unit by using the TPM.

In the present application, the first threshold is a positive integer, for example, the first threshold takes a value of 2, 3, 4, 5 or 6.

In one possible implementation, the method further includes: when a plurality of CUs in the preset video processing unit are allowed to be processed by using TPMs, the TPM identifier corresponding to the preset video processing unit is assigned to be a first value;

and when the TPM is forbidden to process the plurality of CUs in the preset video processing unit, assigning the TPM identification as a second value, wherein the first value is different from the second value.

In this application, after determining whether the preset video processing unit allows the processing using the TPM, the decoder needs to assign a value to the TPM identifier in the syntax element to mark whether the preset video processing unit uses the TPM for processing.

In a possible implementation manner, the first prediction parameter is a maximum number of candidate motion vector lists corresponding to the preset video processing unit, and the determining, according to the first prediction parameter, whether to allow processing of the multiple CUs in the preset video processing unit using the TPM includes: comparing the maximum number with a second threshold; when the maximum number is greater than or equal to the second threshold value, analyzing and obtaining TPM (tire platform module) identifiers corresponding to the preset video processing units from the code stream, and determining whether to allow the TPM to process a plurality of CUs in the preset video processing units according to the values of the TPM identifiers; when the value of the TPM identifier is a first value, allowing the TPM to process a plurality of CUs in the preset video processing unit; and when the value of the TPM identifier is a second value, prohibiting the TPM from being used for processing a plurality of CUs in the preset video processing unit, wherein the first value is different from the second value.

In this application, the second threshold is a positive integer, for example, the second threshold has a value of 2, 3, 4, 5, or 6.

In one possible implementation, the method further includes: and when the maximum number is smaller than the second threshold value, determining whether to allow the TPM to process a plurality of CUs in the preset video processing unit according to the preset value of the TPM identifier.

In the present application, the encoder and the decoder may negotiate a preset value (may also be referred to as a default value) of the TPM identifier in advance, and at this time, the code stream may not carry the value of the TPM identifier.

In one possible implementation, the method further includes: and when the code stream does not contain the value information of the TPM identifier, setting the preset value of the TPM identifier as the second value.

In the present application, when the code stream does not carry the value of the TPM identifier, the decoder may set the preset value (i.e., the default value) of the TPM identifier by itself.

In one possible implementation, when processing of the CU to be processed using the TPM is prohibited, the method further includes: and determining that the code stream does not contain TPM grammar information of the CU to be processed, wherein the TPM grammar information is used for constructing a predicted value obtained by the CU to be processed based on a TPM.

In the method, when the encoding end determines that the TPM is prohibited to process the CU to be processed, the encoding end does not carry TPM grammar information of the CU to be processed in the code stream and transmits the TPM grammar information to the decoding end, and then the decoding end can determine that the code stream does not contain the TPM grammar information of the CU to be processed when determining that the TPM is prohibited to process the CU to be processed, so that the code stream is not required to be analyzed, and the data processing amount is reduced.

In a second aspect, the present application provides a processing method based on a triangular prediction unit mode, including: obtaining the maximum number of candidate motion vector lists corresponding to a preset video processing unit; determining whether to allow processing of a plurality of coding units CUs in the preset video processing unit by using a triangular prediction unit mode TPM according to the maximum number, wherein the plurality of CUs comprise CUs to be processed; and when the TPM is forbidden to process the plurality of CUs in the preset video processing unit, the TPM is forbidden to process the CUs to be processed.

In one possible implementation, the method further includes: when the TPM is allowed to process a plurality of CUs in the preset video processing unit, determining whether to process the CUs to be processed by using the TPM according to the maximum number of candidate motion vector lists corresponding to the CUs to be processed.

In a possible implementation manner, the determining, according to the maximum number, whether to allow processing of the plurality of CUs in the preset video processing unit using the TPM includes: comparing the maximum number with a first threshold;

when the maximum number is greater than or equal to the first threshold, allowing the TPM to process a plurality of CUs in the preset video processing unit; and when the maximum number is smaller than the first threshold value, prohibiting the TPM from being used for processing the plurality of CUs in the preset video processing unit.

In a possible implementation manner, the determining, according to the maximum number, whether to allow processing of the plurality of CUs in the preset video processing unit using the TPM includes: comparing the maximum number with a second threshold; and when the maximum number is smaller than the second threshold value, determining whether to allow the TPM to process the plurality of CUs in the preset video processing unit according to rate distortion optimization.

In one possible implementation, the method further includes: when a plurality of CUs in the preset video processing unit are allowed to be processed by using TPMs, the TPM identifier corresponding to the preset video processing unit is assigned to be a first value; and when the TPM is forbidden to process the plurality of CUs in the preset video processing unit, assigning the TPM identification as a second value, wherein the first value is different from the second value.

In one possible implementation, when processing of the CU to be processed using the TPM is prohibited, the method further includes: and omitting encoding of TPM grammar information of the CU to be processed, wherein the TPM grammar information is used for constructing a predicted value of the CU to be processed, which is obtained based on a TPM.

In a third aspect, the present application provides an inter prediction apparatus, including: the analysis module is used for analyzing and obtaining a first prediction parameter from the code stream, and the first prediction parameter is used for processing a preset video processing unit; the determining module is used for determining whether to allow the processing of a plurality of coding units CU in a preset video processing unit by using a triangular prediction unit mode TPM according to the first prediction parameter, wherein the plurality of CUs comprise CUs to be processed; and when the TPM is forbidden to process the plurality of CUs in the preset video processing unit, the TPM is forbidden to process the CUs to be processed.

In a possible implementation manner, the determining module is further configured to, when processing is allowed to be performed on a plurality of CUs in the preset video processing unit by using a TPM, parse and obtain a second prediction parameter from the code stream, where the second prediction parameter is used to process the CU to be processed; and determining whether to use the TPM to process the CU to be processed according to the second prediction parameters.

In a possible implementation manner, the determining module is specifically configured to determine that the TPM is allowed to process the plurality of CUs in the preset video processing unit when the value of the first prediction parameter is a first value; and when the value of the first prediction parameter is a second value, determining to prohibit processing of a plurality of CUs in the preset video processing unit by using a TPM, wherein the first value is different from the second value.

In a possible implementation manner, when the first prediction parameter is the maximum number of candidate motion vector lists corresponding to the preset video processing unit, the determining module is specifically configured to compare the maximum number with a first threshold value, and determine whether to allow processing of multiple CUs in the preset video processing unit using a TPM; when the maximum number is greater than or equal to the first threshold value, determining that the TPM is allowed to process a plurality of CUs in the preset video processing unit; and when the maximum number is smaller than the first threshold value, prohibiting the TPM from being used for processing the plurality of CUs in the preset video processing unit.

In one possible implementation manner, the apparatus further includes: the optimizing module is used for assigning TPM identifiers corresponding to the preset video processing units to be a first value when the TPM is allowed to process a plurality of CUs in the preset video processing units; and when the TPM is forbidden to process the plurality of CUs in the preset video processing unit, assigning the TPM identification as a second value, wherein the first value is different from the second value.

In a possible implementation manner, when the first prediction parameter is the maximum number of candidate motion vector lists corresponding to the preset video processing unit, the determining module is specifically configured to compare the maximum number with a second threshold; when the maximum number is greater than or equal to the second threshold value, analyzing and obtaining TPM identifiers corresponding to the preset video processing units from the code stream, and determining whether to allow the TPM to process a plurality of CUs in the preset video processing units according to the values of the TPM identifiers; when the value of the TPM identifier is a first value, allowing the TPM to process a plurality of CUs in the preset video processing unit; and when the value of the TPM identifier is a second value, prohibiting the TPM from being used for processing a plurality of CUs in the preset video processing unit, wherein the first value is different from the second value.

In a possible implementation manner, the determining module is further configured to determine, according to a preset value of the TPM identifier, whether to allow processing of the multiple CUs in the preset video processing unit using the TPM when the maximum number is less than the second threshold.

In a possible implementation manner, the determining module is further configured to set a preset value of the TPM identifier to a second value when the code stream does not include the value information of the TPM identifier.

In a possible implementation manner, the determining module is further configured to determine that the code stream does not include TPM syntax information of the CU to be processed when processing of the encoded CU using a TPM is prohibited, where the TPM syntax information is used to construct a predicted value of the CU to be processed based on the TPM.

In a fourth aspect, the present application provides an inter prediction apparatus, including: the obtaining module is used for obtaining the maximum number of candidate motion vector lists corresponding to the preset video processing unit; a determining module, configured to determine whether to allow processing of a plurality of coding units CU in the preset video processing unit using a triangular prediction unit mode TPM according to the maximum number, where the plurality of CUs include CUs to be processed; and when the TPM is forbidden to process the plurality of coding units CU in the preset video processing unit, the TPM is forbidden to process the CU to be processed.

In a possible implementation manner, the determining module is further configured to determine, when processing is allowed to be performed on the plurality of coding units CU in the preset video processing unit using the TPM, whether to use the TPM to process the CU to be processed according to the maximum number of candidate motion vector lists corresponding to the CU to be processed.

In a possible implementation manner, the determining module is specifically configured to compare the maximum number with a first threshold value, and determine whether to allow processing of the plurality of coding units CU in the preset video processing unit using the TPM; when the maximum number is greater than or equal to the first threshold value, allowing the TPM to process a plurality of coding units CU in the preset video processing unit; and when the maximum number is smaller than the first threshold value, prohibiting the TPM from being used for processing the plurality of coding units CU in the preset video processing unit.

In a possible implementation, the determining module is specifically configured to compare the maximum number with a second threshold value; and when the maximum number is smaller than the second threshold value, determining whether to allow the TPM to process the plurality of coding units CU in the preset video processing unit according to rate distortion optimization.

In one possible implementation, the apparatus further includes: the optimizing module is used for assigning the TPM identification corresponding to the preset video processing unit to a first value when the TPM is allowed to process the plurality of coding units CU in the preset video processing unit; and when the TPM is forbidden to process the plurality of coding units CU in the preset video processing unit, assigning the TPM identification to a second value, wherein the first value is different from the second value.

In one possible implementation, the apparatus further includes: and the optimizing module is used for omitting the encoding of TPM grammar information of the CU to be processed when the CU to be processed is forbidden to be processed by using the TPM, wherein the TPM grammar information is used for constructing a predicted value of the CU to be processed, which is obtained based on the TPM.

In a fifth aspect, the present application provides a video encoder for encoding an image block, comprising: the inter-prediction apparatus according to any one of the fourth aspect, wherein the inter-prediction apparatus is configured to predict motion information of a current encoded image block based on target candidate motion information, and determine a predicted pixel value of the current encoded image block based on the motion information of the current encoded image block; an entropy encoding module for encoding an index identification of the target candidate motion information into a bitstream, the index identification indicating the target candidate motion information for the current encoded image block; a reconstruction module for reconstructing the current encoded image block based on the predicted pixel values.

In a sixth aspect, the present application provides a video decoder for decoding image blocks from a bitstream, comprising: the entropy decoding module is used for decoding an index identifier from the code stream, wherein the index identifier is used for indicating target candidate motion information of the current decoded image block; an inter-frame prediction apparatus as claimed in any one of the third aspects above, the inter-frame prediction apparatus being operable to predict motion information of a current decoded image block based on target candidate motion information indicated by the index identification, and to determine a predicted pixel value of the current decoded image block based on the motion information of the current decoded image block; a reconstruction module for reconstructing the current decoded image block based on the predicted pixel values.

In a seventh aspect, the present application provides an apparatus for decoding video data, the apparatus comprising:

a memory for storing video data in the form of a code stream;

and the video decoder is used for decoding the video data from the code stream.

In an eighth aspect, the present application provides an apparatus for encoding video data, the apparatus comprising:

a memory for storing video data, the video data comprising one or more image blocks;

And the video encoder is used for generating a code stream according to the video data.

In a ninth aspect, the present application provides a decoding apparatus, including: a non-volatile memory and a processor coupled to each other, the processor invoking program code stored in the memory to perform some or all of the steps of any of the methods of the first aspect.

In a tenth aspect, the present application provides an encoding apparatus, including: a non-volatile memory and a processor coupled to each other, the processor invoking program code stored in the memory to perform part or all of the steps of any of the methods of the second aspect.

In an eleventh aspect, the present application provides a computer readable storage medium storing program code, wherein the program code comprises instructions for performing part or all of the steps of any one of the methods of the first aspect.

In a twelfth aspect, the present application provides a computer program product for causing a computer to perform some or all of the steps of any one of the methods of the first and second aspects when the computer program product is run on the computer.

In a thirteenth aspect, the present application provides a decoding method of inter prediction, including: parsing a first identifier from a code stream, wherein the first identifier is used for determining whether a triangular prediction mode is allowed to be used in a preset video processing unit, and the preset video processing unit comprises a plurality of decoding units; and obtaining a prediction mode of a decoding unit to be processed based on the first identification, wherein the decoding unit to be processed belongs to the plurality of decoding units.

In one possible implementation manner, the preset video processing unit includes: a tile group, a frame of images or a video sequence.

In one possible implementation manner, when the first identifier is located at a slice group header in the code stream, the preset video processing unit is a slice group corresponding to the slice group header.

In one possible implementation, the method further includes: and resolving a second identifier from the slice group header, wherein the second identifier is used for indicating the maximum capacity of a preset candidate prediction mode list of the decoding unit to be processed.

In one possible implementation, when the first identifier is located in an image parameter set (picture parameter set) in the code stream, the preset video processing unit is an image corresponding to the image parameter set.

In one possible implementation, the method further includes: and resolving a third identifier from the image parameter set, wherein the third identifier is used for indicating the maximum capacity of a preset candidate prediction mode list of the decoding unit to be processed.

In one possible implementation manner, when the first identifier is located in a sequence parameter set (sequence parameter set) in the code stream, the preset video processing unit is a video sequence corresponding to the sequence parameter set.

In one possible implementation, the method further includes: and analyzing a fourth identifier from the sequence parameter set, wherein the fourth identifier is used for indicating the maximum capacity of a preset candidate prediction mode list of the decoding unit to be processed.

In one possible implementation, the preset candidate prediction mode list is a merge (merge) mode candidate prediction mode list.

In a fourteenth aspect, the present application provides a decoding method of inter prediction, including: analyzing a fifth identifier from the code stream, wherein the fifth identifier is used for indicating the maximum capacity of a preset candidate prediction mode list of the decoding unit to be processed; and obtaining a prediction mode of the decoding unit to be processed based on the maximum capacity.

In a possible implementation manner, when the maximum capacity is smaller than a preset threshold, the prediction mode of the decoding unit to be processed is not allowed to include a triangular prediction mode; or when the maximum capacity is greater than or equal to the preset threshold, the prediction mode of the decoding unit to be processed is allowed to include the triangular prediction mode.

In a possible implementation manner, the obtaining, based on the maximum capacity, a prediction mode of a decoding unit to be processed includes: when the maximum capacity is greater than or equal to the preset threshold value, a seventh identifier is analyzed from the code stream, wherein the seventh identifier is used for indicating whether the prediction mode of the decoding unit to be processed allows a triangular prediction mode to be used or not; and obtaining the prediction mode of the decoding unit to be processed based on the seventh identifier.

In a possible implementation manner, when the seventh flag is a first value, the prediction mode of the decoding unit to be processed allows to include the triangular prediction mode; when the seventh flag is a second value, the prediction mode of the decoding unit to be processed is not allowed to include the triangular prediction mode, and the first value is not equal to the second value.

In one possible implementation, when the maximum capacity is smaller than the preset threshold, it is determined that the prediction mode of the decoding unit to be processed allows the triangular prediction mode to be included.

In one possible implementation, when the maximum capacity is smaller than the preset threshold, it is determined that the prediction mode of the decoding unit to be processed is not allowed to include the triangular prediction mode.

In one possible implementation, the method further includes: setting a sixth identifier as a first value when the prediction mode of the decoding unit to be processed is allowed to include a triangular prediction mode; or when the prediction mode of the decoding unit to be processed does not allow the triangular prediction mode to be included, setting the sixth identifier as a second numerical value, wherein the first numerical value is not equal to the second numerical value.

In one possible implementation, the preset threshold includes: 2. 3, 4, 5 or 6.

In one possible implementation manner, the fifth identifier is located at a slice group header in the code stream, and the corresponding decoding unit to be processed is located in a slice group corresponding to the slice group header.

In a possible implementation manner, the fifth identifier is located in an image parameter set in the code stream, and the corresponding decoding unit to be processed is located in an image corresponding to the image parameter set.

In a possible implementation manner, the fifth identifier is located in a sequence parameter set in the code stream, and the corresponding decoding unit to be processed is located in a video sequence corresponding to the sequence parameter set.

In one possible implementation, the preset candidate prediction mode list is a fusion mode candidate prediction mode list.

It should be understood that, in the third to fourteenth aspects of the present application, the technical solutions of the first aspect and the second aspect of the present application are consistent, and the advantages obtained by each aspect and the corresponding possible embodiments are similar, and are not repeated.

Drawings

In order to more clearly describe the technical solutions in the embodiments or the background of the present application, the following description will describe the drawings that are required to be used in the embodiments or the background of the present application.

FIG. 1A is a block diagram of an example of a video encoding and decoding system 10 for implementing embodiments of the present application;

FIG. 1B is a block diagram of an example of a video coding system 40 for implementing embodiments of the present application;

FIG. 2 is a block diagram of an example structure of an encoder 20 for implementing embodiments of the present application;

FIG. 3 is a block diagram of an example architecture of a decoder 30 for implementing embodiments of the present application;

fig. 4 is a block diagram of an example of a video coding apparatus 400 for implementing an embodiment of the present application;

FIG. 5 is a block diagram of another example encoding or decoding device for implementing embodiments of the present application;

fig. 6 is a schematic diagram of a current image block in a spatial domain and a temporal domain in an embodiment of the present application;

FIG. 7 is a schematic diagram of a triangular prediction unit according to an embodiment of the present application;

FIG. 8 is a schematic diagram illustrating a partition manner of a triangle prediction unit according to an embodiment of the present application;

FIG. 9 is a flowchart of a TPM-based processing method in an embodiment of the present application;

fig. 10 is a schematic structural diagram of an inter prediction apparatus according to an embodiment of the present application;

fig. 11 is another schematic structural diagram of an inter prediction apparatus in an embodiment of the present application.

Detailed Description

Embodiments of the present application are described below with reference to the accompanying drawings in the embodiments of the present application. In the following description, reference is made to the accompanying drawings which form a part hereof and which show by way of illustration specific aspects in which embodiments of the application may be practiced. It is to be understood that the embodiments of the present application may be used in other respects and may include structural or logical changes not depicted in the drawings. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present application is defined by the appended claims. For example, it should be understood that the disclosure in connection with the described methods may be equally applicable to a corresponding apparatus or system for performing the methods, and vice versa. For example, if one or more specific method steps are described, the corresponding apparatus may comprise one or more units, such as functional units, to perform the one or more described method steps (e.g., one unit performing one or more steps, or multiple units each performing one or more of the multiple steps), even if such one or more units are not explicitly described or illustrated in the figures. On the other hand, if a specific apparatus is described based on one or more units such as a functional unit, for example, the corresponding method may include one step to perform the functionality of the one or more units (e.g., one step to perform the functionality of the one or more units, or multiple steps each to perform the functionality of one or more units, even if such one or more steps are not explicitly described or illustrated in the figures). Further, it is to be understood that features of the various exemplary embodiments and/or aspects described herein may be combined with each other, unless explicitly stated otherwise.

The technical scheme related to the embodiment of the application can be applied to the existing video coding standards (such as H.264, HEVC and the like) and future video coding standards (such as H.266). The terminology used in the description section of the present application is for the purpose of describing particular embodiments of the present application only and is not intended to be limiting of the present application. Some concepts that may be related to embodiments of the present application are briefly described below.

Video coding generally refers to processing a sequence of pictures that form a video or video sequence. In the field of video coding, the terms "picture", "frame" or "image" may be used as synonyms. Video encoding as used herein refers to video encoding or video decoding. Video encoding is performed on the source side, typically including processing (e.g., by compression) the original video picture to reduce the amount of data required to represent the video picture, thereby more efficiently storing and/or transmitting. Video decoding is performed on the destination side, typically involving inverse processing with respect to the encoder to reconstruct the video pictures. The embodiment relates to video picture "encoding" is understood to relate to "encoding" or "decoding" of a video sequence. The combination of the encoding portion and the decoding portion is also called codec (encoding and decoding).

A video sequence comprises a series of pictures (pictures) which are further divided into slices (slices) which are further divided into blocks (blocks). Video coding performs coding processing in units of blocks, and in some new video coding standards, the concept of blocks is further extended. For example, in the h.264 standard, there are Macro Blocks (MBs), which can be further divided into a plurality of prediction blocks (partition) that can be used for predictive coding. In the high performance video coding (high efficiency video coding, HEVC) standard, basic concepts such as a Coding Unit (CU), a Prediction Unit (PU), and a Transform Unit (TU) are adopted, and various block units are functionally divided and described by using a brand new tree-based structure. For example, the video coding standard divides a frame of image into Coding Tree Units (CTUs) that do not overlap with each other, and divides a CTU into a plurality of sub-nodes, where the sub-nodes may be divided into smaller sub-nodes according to a Quadtree (QT), and the smaller sub-nodes may be further divided, so as to form a quadtree structure. If the nodes are no longer partitioned, they are called CUs. A CU is a basic unit that divides and encodes an encoded image. Similar tree structures exist for PUs and TUs, which may correspond to prediction blocks, being the basic unit of predictive coding. The CU is further divided into a plurality of PUs according to a division pattern. The TU may correspond to a transform block, which is a basic unit for transforming a prediction residual. However, whether CU, PU or TU, essentially belongs to the concept of blocks (or picture blocks).

In HEVC, for example, CTUs are split into multiple CUs by using a quadtree structure denoted as coding tree. A decision is made at the CU level whether to encode a picture region using inter-picture (temporal) or intra-picture (spatial) prediction. Each CU may be further split into one, two, or four PUs depending on the PU split type. The same prediction process is applied within one PU and the relevant information is transmitted to the decoder on a PU basis. After the residual block is obtained by applying the prediction process based on the PU split type, the CU may be partitioned into Transform Units (TUs) according to other quadtree structures similar to the coding tree for the CU. In a recent development of video compression technology, a Quad tree and a binary tree (qd-tree and binary tree, QTBT) partition frames are used to partition the encoded blocks. In QTBT block structures, a CU may be square or rectangular in shape.

Herein, for convenience of description and understanding, an image block to be encoded in a current encoded image may be referred to as a current block, for example, in encoding, a block currently being encoded; in decoding, a block currently being decoded is referred to. A decoded image block in a reference image used for predicting a current block is referred to as a reference block, i.e. a reference block is a block providing a reference signal for the current block, wherein the reference signal represents pixel values within the image block. A block in the reference picture that provides a prediction signal for the current block may be referred to as a prediction block, where the prediction signal represents pixel values or sample signals within the prediction block. For example, after traversing multiple reference blocks, the best reference block is found, which will provide prediction for the current block, which is referred to as the prediction block.

In the case of lossless video coding, the original video picture may be reconstructed, i.e., the reconstructed video picture has the same quality as the original video picture (assuming no transmission loss or other data loss during storage or transmission). In the case of lossy video coding, the amount of data needed to represent a video picture is reduced by performing further compression, e.g. quantization, whereas the decoder side cannot reconstruct the video picture completely, i.e. the quality of the reconstructed video picture is lower or worse than the quality of the original video picture.

Several video coding standards of h.261 belong to the "lossy hybrid video codec" (i.e. spatial and temporal prediction in the sample domain is combined with 2D transform coding in the transform domain for applying quantization). Each picture of a video sequence is typically partitioned into non-overlapping sets of blocks, typically encoded at the block level. In other words, the encoder side typically processes, i.e. encodes, video at the block (video block) level, e.g. generates a prediction block by spatial (intra-picture) prediction and temporal (inter-picture) prediction, subtracts the prediction block from the current block (currently processed or to-be-processed block) to obtain a residual block, transforms the residual block in the transform domain and quantizes the residual block to reduce the amount of data to be transmitted (compressed), while the decoder side applies the inverse processing part of the relative encoder to the encoded or compressed block to reconstruct the current block for representation. In addition, the encoder replicates the decoder processing loop so that the encoder and decoder generate the same predictions (e.g., intra-prediction and inter-prediction) and/or reconstructions for processing, i.e., encoding, the subsequent blocks.

The system architecture to which the embodiments of the present application apply is described below. Referring to fig. 1A, fig. 1A schematically illustrates a block diagram of a video encoding and decoding system 10 to which embodiments of the present application are applied. As shown in fig. 1A, video encoding and decoding system 10 may include a source device 12 and a destination device 14, source device 12 generating encoded video data, and thus source device 12 may be referred to as a video encoding apparatus. Destination device 14 may decode encoded video data generated by source device 12, and thus destination device 14 may be referred to as a video decoding apparatus. Various implementations of source apparatus 12, destination apparatus 14, or both may include one or more processors and memory coupled to the one or more processors. The memory may include, but is not limited to RAM, ROM, EEPROM, flash memory, or any other medium that can be used to store the desired program code in the form of instructions or data structures that can be accessed by a computer, as described herein. The source device 12 and the destination device 14 may include a variety of devices including desktop computers, mobile computing devices, notebook (e.g., laptop) computers, tablet computers, set-top boxes, telephone handsets such as so-called "smart" phones, televisions, cameras, display devices, digital media players, video game consoles, vehicle mount computers, wireless communication devices, or the like.

Although fig. 1A depicts source device 12 and destination device 14 as separate devices, device embodiments may also include the functionality of both source device 12 and destination device 14, or both, i.e., source device 12 or corresponding functionality and destination device 14 or corresponding functionality. In such embodiments, the source device 12 or corresponding functionality and the destination device 14 or corresponding functionality may be implemented using the same hardware and/or software, or using separate hardware and/or software, or any combination thereof.

A communication connection may be made between source device 12 and destination device 14 via link 13, and destination device 14 may receive encoded video data from source device 12 via link 13. Link 13 may include one or more media or devices capable of moving encoded video data from source device 12 to destination device 14. In one example, link 13 may include one or more communication media that enable source device 12 to transmit encoded video data directly to destination device 14 in real-time. In this example, source apparatus 12 may modulate the encoded video data according to a communication standard, such as a wireless communication protocol, and may transmit the modulated video data to destination apparatus 14. The one or more communication media may include wireless and/or wired communication media such as a Radio Frequency (RF) spectrum or one or more physical transmission lines. The one or more communication media may form part of a packet-based network, such as a local area network, a wide area network, or a global network (e.g., the internet). The one or more communication media may include routers, switches, base stations, or other equipment that facilitate communication from source apparatus 12 to destination apparatus 14.

Source device 12 includes an encoder 20 and, alternatively, source device 12 may also include a picture source 16, a picture preprocessor 18, and a communication interface 22. In a specific implementation, the encoder 20, the picture source 16, the picture preprocessor 18, and the communication interface 22 may be hardware components in the source device 12 or may be software programs in the source device 12. The descriptions are as follows:

the picture source 16 may include or be any type of picture capture device for capturing, for example, real world pictures, and/or any type of picture or comment (for screen content encoding, some text on the screen is also considered part of the picture or image to be encoded), for example, a computer graphics processor for generating computer animated pictures, or any type of device for capturing and/or providing real world pictures, computer animated pictures (e.g., screen content, virtual Reality (VR) pictures), and/or any combination thereof (e.g., live (augmented reality, AR) pictures). Picture source 16 may be a camera for capturing pictures or a memory for storing pictures, picture source 16 may also include any type of (internal or external) interface for storing previously captured or generated pictures and/or for capturing or receiving pictures. When picture source 16 is a camera, picture source 16 may be, for example, an integrated camera, either local or integrated in the source device; when picture source 16 is memory, picture source 16 may be local or integrated memory integrated in the source device, for example. When the picture source 16 comprises an interface, the interface may for example be an external interface receiving pictures from an external video source, for example an external picture capturing device, such as a camera, an external memory or an external picture generating device, for example an external computer graphics processor, a computer or a server. The interface may be any kind of interface according to any proprietary or standardized interface protocol, e.g. a wired or wireless interface, an optical interface.

Wherein a picture can be regarded as a two-dimensional array or matrix of pixel elements. The pixels in the array may also be referred to as sampling points. The number of sampling points of the array or picture in the horizontal and vertical directions (or axes) defines the size and/or resolution of the picture. To represent color, three color components are typically employed, i.e., a picture may be represented as or contain three sample arrays. For example, in RBG format or color space, the picture includes corresponding red, green, and blue sample arrays. However, in video coding, each pixel is typically represented in a luminance/chrominance format or color space, e.g., for a picture in YUV format, comprising a luminance component indicated by Y (which may sometimes also be indicated by L) and two chrominance components indicated by U and V. The luminance (luma) component Y represents the luminance or grayscale level intensity (e.g., the same in a grayscale picture), while the two chrominance (chroma) components U and V represent the chrominance or color information components. Accordingly, a picture in YUV format includes a luminance sample array of luminance sample values (Y) and two chrominance sample arrays of chrominance values (U and V). Pictures in RGB format may be converted or transformed into YUV format and vice versa, a process also known as color transformation or conversion. If the picture is black and white, the picture may include only an array of luma samples. In the present embodiment, the picture transmitted by the picture source 16 to the picture processor may also be referred to as the original picture data 17.

A picture preprocessor 18 for receiving the original picture data 17 and performing preprocessing on the original picture data 17 to obtain a preprocessed picture 19 or preprocessed picture data 19. For example, the preprocessing performed by the picture preprocessor 18 may include truing, color format conversion (e.g., from RGB format to YUV format), toning, or denoising.

Encoder 20 (or video encoder 20) receives pre-processed picture data 19, and processes pre-processed picture data 19 using an associated prediction mode (e.g., a prediction mode in various embodiments herein) to provide encoded picture data 21 (details of the structure of encoder 20 will be described further below based on fig. 2 or fig. 4 or fig. 5). In some embodiments, encoder 20 may be configured to perform various embodiments described below to implement the application of the chroma block prediction method described herein on the encoding side.

Communication interface 22 may be used to receive encoded picture data 21 and may transmit encoded picture data 21 over link 13 to destination device 14 or any other device (e.g., memory) for storage or direct reconstruction, which may be any device for decoding or storage. Communication interface 22 may be used, for example, to encapsulate encoded picture data 21 into a suitable format, such as a data packet, for transmission over link 13.

Destination device 14 includes a decoder 30, and alternatively destination device 14 may also include a communication interface 28, a picture post-processor 32, and a display device 34. The descriptions are as follows:

communication interface 28 may be used to receive encoded picture data 21 from source device 12 or any other source, such as a storage device, such as an encoded picture data storage device. The communication interface 28 may be used to transmit or receive encoded picture data 21 via a link 13 between the source device 12 and the destination device 14, such as a direct wired or wireless connection, or via any type of network, such as a wired or wireless network or any combination thereof, or any type of private and public networks, or any combination thereof. Communication interface 28 may, for example, be used to decapsulate data packets transmitted by communication interface 22 to obtain encoded picture data 21.

Both communication interface 28 and communication interface 22 may be configured as unidirectional communication interfaces or bidirectional communication interfaces and may be used, for example, to send and receive messages to establish connections, to acknowledge and to exchange any other information related to the communication link and/or to the transmission of data, for example, encoded picture data transmissions.

Decoder 30 (or referred to as decoder 30) for receiving encoded picture data 21 and providing decoded picture data 31 or decoded picture 31 (details of the structure of decoder 30 will be described below further based on fig. 3 or fig. 4 or fig. 5). In some embodiments, decoder 30 may be configured to perform various embodiments described below to implement the application of the chroma block prediction method described herein on the decoding side.

A picture post-processor 32 for performing post-processing on the decoded picture data 31 (also referred to as reconstructed slice data) to obtain post-processed picture data 33. The post-processing performed by the picture post-processor 32 may include: color format conversion (e.g., from YUV format to RGB format), toning, truing, or resampling, or any other process, may also be used to transmit post-processed picture data 33 to display device 34.

A display device 34 for receiving the post-processed picture data 33 for displaying pictures to, for example, a user or viewer. The display device 34 may be or include any type of display for presenting reconstructed pictures, for example, an integrated or external display or monitor. For example, the display may include a liquid crystal display (liquid crystal display, LCD), an organic light emitting diode (organic light emitting diode, OLED) display, a plasma display, a projector, a micro LED display, a liquid crystal on silicon (liquid crystal on silicon, LCoS), a digital light processor (digital light processor, DLP), or any other type of display.

It will be apparent to those skilled in the art from this description that the functionality of the different units or the existence and (exact) division of the functionality of the source device 12 and/or destination device 14 shown in fig. 1A may vary depending on the actual device and application. Source device 12 and destination device 14 may comprise any of a variety of devices, including any type of handheld or stationary device, such as a notebook or laptop computer, mobile phone, smart phone, tablet or tablet computer, video camera, desktop computer, set-top box, television, camera, in-vehicle device, display device, digital media player, video game console, video streaming device (e.g., content service server or content distribution server), broadcast receiver device, broadcast transmitter device, etc., and may not use or use any type of operating system.

Encoder 20 and decoder 30 may each be implemented as any of a variety of suitable circuits, such as, for example, one or more microprocessors, digital signal processors (digital signal processor, DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), discrete logic, hardware or any combinations thereof. If the techniques are implemented in part in software, an apparatus may store instructions of the software in a suitable non-transitory computer-readable storage medium and may execute the instructions in hardware using one or more processors to perform the techniques of this disclosure. Any of the foregoing (including hardware, software, a combination of hardware and software, etc.) may be considered one or more processors.

In some cases, the video encoding and decoding system 10 shown in fig. 1A is merely an example, and the techniques of this disclosure may be applicable to video encoding settings (e.g., video encoding or video decoding) that do not necessarily involve any data communication between encoding and decoding devices. In other examples, the data may be retrieved from local memory, streamed over a network, and the like. The video encoding device may encode and store data to the memory and/or the video decoding device may retrieve and decode data from the memory. In some examples, encoding and decoding are performed by devices that do not communicate with each other, but instead only encode data to memory and/or retrieve data from memory and decode data.

Referring to fig. 1B, fig. 1B is an illustration of an example of a video coding system 40 including encoder 20 of fig. 2 and/or decoder 30 of fig. 3, according to an example embodiment. Video coding system 40 may implement a combination of the various techniques of the embodiments of the present application. In the illustrated embodiment, video coding system 40 may include an imaging device 41, an encoder 20, a decoder 30 (and/or a video codec implemented by logic circuitry 47 of a processing unit 46), an antenna 42, one or more processors 43, one or more memories 44, and/or a display device 45.

As shown in fig. 1B, the imaging device 41, the antenna 42, the processing unit 46, the logic circuit 47, the encoder 20, the decoder 30, the processor 43, the memory 44, and/or the display device 45 can communicate with each other. As discussed, although video coding system 40 is depicted with encoder 20 and decoder 30, in different examples, video coding system 40 may include only encoder 20 or only decoder 30.

In some examples, antenna 42 may be used to transmit or receive an encoded bitstream of video data. Additionally, in some examples, display device 45 may be used to present video data. In some examples, logic 47 may be implemented by processing unit 46. The processing unit 46 may comprise application-specific integrated circuit (ASIC) logic, a graphics processor, a general-purpose processor, or the like. The video coding system 40 may also include an optional processor 43, which optional processor 43 may similarly include application-specific integrated circuit (ASIC) logic, a graphics processor, a general purpose processor, or the like. In some examples, logic 47 may be implemented in hardware, such as video encoding dedicated hardware, processor 43 may be implemented in general purpose software, an operating system, or the like. In addition, the memory 44 may be any type of memory, such as volatile memory (e.g., static random access memory (Static Random Access Memory, SRAM), dynamic random access memory (Dynamic Random Access Memory, DRAM), etc.) or non-volatile memory (e.g., flash memory, etc.), and the like. In a non-limiting example, the memory 44 may be implemented by an overspeed cache. In some examples, logic circuitry 47 may access memory 44 (e.g., for implementing an image buffer). In other examples, logic 47 and/or processing unit 46 may include memory (e.g., a cache, etc.) for implementing an image buffer, etc.

In some examples, encoder 20 implemented by logic circuitry may include an image buffer (e.g., implemented by processing unit 46 or memory 44) and a graphics processing unit (e.g., implemented by processing unit 46). The graphics processing unit may be communicatively coupled to the image buffer. The graphics processing unit may include encoder 20 implemented by logic circuitry 47 to implement the various modules discussed with reference to fig. 2 and/or any other encoder system or subsystem described herein. Logic circuitry may be used to perform various operations discussed herein.

In some examples, decoder 30 may be implemented in a similar manner by logic circuit 47 to implement the various modules discussed with reference to decoder 30 of fig. 3 and/or any other decoder system or subsystem described herein. In some examples, decoder 30 implemented by logic circuitry may include an image buffer (implemented by processing unit 43 or memory 44) and a graphics processing unit (e.g., implemented by processing unit 46). The graphics processing unit may be communicatively coupled to the image buffer. The graphics processing unit may include decoder 30 implemented by logic circuit 47 to implement the various modules discussed with reference to fig. 3 and/or any other decoder system or subsystem described herein.

In some examples, antenna 42 may be used to receive an encoded bitstream of video data. As discussed, the encoded bitstream may include data related to the encoded video frame, indicators, index values, mode selection data, etc., discussed herein, such as data related to the encoded partitions (e.g., transform coefficients or quantized transform coefficients, optional indicators (as discussed), and/or data defining the encoded partitions). Video coding system 40 may also include a decoder 30 coupled to antenna 42 and used to decode the encoded bitstream. The display device 45 is used to present video frames.

It should be understood that for the example described with reference to encoder 20 in the embodiments of the present application, decoder 30 may be used to perform the reverse process. Regarding signaling syntax elements, decoder 30 may be configured to receive and parse such syntax elements and decode the associated video data accordingly. In some examples, encoder 20 may entropy encode the syntax elements into an encoded video bitstream. In such examples, decoder 30 may parse such syntax elements and decode the relevant video data accordingly.

It should be noted that, the optimization processing method for merging motion vector difference techniques described in the embodiments of the present application is mainly used in an inter-frame prediction process, where the process exists in both the encoder 20 and the decoder 30, and the encoder 20 and the decoder 30 in the embodiments of the present application may be, for example, an encoder/decoder corresponding to a video standard protocol such as h.263, h.264, HEVV, MPEG-2, MPEG-4, VP8, VP9, or a next-generation video standard protocol (such as h.266, etc.).

Referring to fig. 2, fig. 2 shows a schematic/conceptual block diagram of an example of an encoder 20 for implementing an embodiment of the present application. In the example of fig. 2, encoder 20 includes a residual calculation unit 204, a transform processing unit 206, a quantization unit 208, an inverse quantization unit 210, an inverse transform processing unit 212, a reconstruction unit 214, a buffer 216, a loop filter unit 220, a decoded picture buffer (decoded picture buffer, DPB) 230, a prediction processing unit 260, and an entropy encoding unit 270. The prediction processing unit 260 may include an inter prediction unit 244, an intra prediction unit 254, and a mode selection unit 262. The inter prediction unit 244 may include a motion estimation unit and a motion compensation unit (not shown). The encoder 20 shown in fig. 2 may also be referred to as a hybrid video encoder or a video encoder according to a hybrid video codec.

For example, the residual calculation unit 204, the transform processing unit 206, the quantization unit 208, the prediction processing unit 260 and the entropy encoding unit 270 form a forward signal path of the encoder 20, whereas for example the inverse quantization unit 210, the inverse transform processing unit 212, the reconstruction unit 214, the buffer 216, the loop filter 220, the decoded picture buffer (decoded picture buffer, DPB) 230, the prediction processing unit 260 form a backward signal path of the encoder, wherein the backward signal path of the encoder corresponds to the signal path of the decoder (see decoder 30 in fig. 3).

Encoder 20 receives picture 201 or an image block 203 of picture 201, e.g., a picture in a sequence of pictures forming a video or video sequence, through, e.g., input 202. Image block 203 may also be referred to as a current picture block or a picture block to be encoded, and picture 201 may be referred to as a current picture or a picture to be encoded (especially when distinguishing the current picture from other pictures in video encoding, such as previously encoded and/or decoded pictures in the same video sequence, i.e., a video sequence that also includes the current picture).

An embodiment of encoder 20 may comprise a partitioning unit (not shown in fig. 2) for partitioning picture 201 into a plurality of blocks, e.g. image blocks 203, typically into a plurality of non-overlapping blocks. The segmentation unit may be used to use the same block size for all pictures in the video sequence and a corresponding grid defining the block size, or to alter the block size between pictures or subsets or groups of pictures and to segment each picture into corresponding blocks.

In one example, prediction processing unit 260 of encoder 20 may be used to perform any combination of the above-described partitioning techniques.

Like picture 201, image block 203 is also or may be considered as a two-dimensional array or matrix of sampling points having sampling values, albeit of smaller size than picture 201. In other words, the image block 203 may comprise, for example, one sampling array (e.g., a luminance array in the case of a black-and-white picture 201) or three sampling arrays (e.g., one luminance array and two chrominance arrays in the case of a color picture) or any other number and/or class of arrays depending on the color format applied. The number of sampling points in the horizontal and vertical directions (or axes) of the image block 203 defines the size of the image block 203.

The encoder 20 as shown in fig. 2 is used for encoding a picture 201 block by block, for example, performing encoding and prediction for each image block 203.

The residual calculation unit 204 is configured to calculate a residual block 205 based on the picture image block 203 and the prediction block 265 (further details of the prediction block 265 are provided below), for example, by subtracting sample values of the prediction block 265 from sample values of the picture image block 203 on a sample-by-sample (pixel-by-pixel) basis to obtain the residual block 205 in a sample domain.

The transform processing unit 206 is configured to apply a transform, such as a discrete cosine transform (discrete cosine transform, DCT) or a discrete sine transform (discrete sine transform, DST), on the sample values of the residual block 205 to obtain transform coefficients 207 in the transform domain. The transform coefficients 207 may also be referred to as transform residual coefficients and represent the residual block 205 in the transform domain.

The transform processing unit 206 may be used to apply integer approximations of DCT/DST, such as the transforms specified for HEVC/H.265. Such integer approximations are typically scaled by some factor compared to the orthogonal DCT transform. To maintain the norms of the forward and inverse transformed processed residual blocks, an additional scaling factor is applied as part of the transformation process. The scaling factor is typically selected based on certain constraints, e.g., the scaling factor is a tradeoff between power of 2, bit depth of transform coefficients, accuracy, and implementation cost for shift operations, etc. For example, a specific scaling factor is specified for inverse transformation by, for example, the inverse transformation processing unit 212 on the decoder 30 side (and for corresponding inverse transformation by, for example, the inverse transformation processing unit 212 on the encoder 20 side), and accordingly, a corresponding scaling factor may be specified for positive transformation by the transformation processing unit 206 on the encoder 20 side.

The quantization unit 208 is for quantizing the transform coefficients 207, for example by applying scalar quantization or vector quantization, to obtain quantized transform coefficients 209. The quantized transform coefficients 209 may also be referred to as quantized residual coefficients 209. The quantization process may reduce the bit depth associated with some or all of the transform coefficients 207. For example, n-bit transform coefficients may be rounded down to m-bit transform coefficients during quantization, where n is greater than m. The quantization level may be modified by adjusting quantization parameters (quantization parameter, QP). For example, for scalar quantization, different scales may be applied to achieve finer or coarser quantization. Smaller quantization step sizes correspond to finer quantization, while larger quantization step sizes correspond to coarser quantization. The appropriate quantization step size may be indicated by QP. For example, the quantization parameter may be an index of a predefined set of suitable quantization steps. For example, smaller quantization parameters may correspond to fine quantization (smaller quantization step size) and larger quantization parameters may correspond to coarse quantization (larger quantization step size) and vice versa. Quantization may involve division by a quantization step size and corresponding quantization or inverse quantization, e.g., performed by inverse quantization 210, or may involve multiplication by a quantization step size. Embodiments according to some standards, such as HEVC, may use quantization parameters to determine quantization step sizes. In general, the quantization step size may be calculated based on quantization parameters using a fixed-point approximation of an equation that includes division. Additional scaling factors may be introduced for quantization and inverse quantization to recover norms of residual blocks that may be modified due to the scale used in the fixed point approximation of the equation for quantization step size and quantization parameters. In one example embodiment, the inverse transformed and inverse quantized scales may be combined. Alternatively, a custom quantization table may be used and signaled from the encoder to the decoder, e.g., in a bitstream. Quantization is a lossy operation, where the larger the quantization step size, the larger the loss.

The inverse quantization unit 210 is configured to apply inverse quantization of the quantization unit 208 on the quantized coefficients to obtain inverse quantized coefficients 211, e.g., apply an inverse quantization scheme of the quantization scheme applied by the quantization unit 208 based on or using the same quantization step size as the quantization unit 208. The dequantized coefficients 211 may also be referred to as dequantized residual coefficients 211, correspond to the transform coefficients 207, although the losses due to quantization are typically different from the transform coefficients.

The inverse transform processing unit 212 is configured to apply an inverse transform of the transform applied by the transform processing unit 206, for example, an inverse discrete cosine transform (discrete cosine transform, DCT) or an inverse discrete sine transform (discrete sine transform, DST), to obtain an inverse transform block 213 in the sample domain. The inverse transform block 213 may also be referred to as an inverse transformed inverse quantized block 213 or an inverse transformed residual block 213.

A reconstruction unit 214 (e.g., a summer 214) is used to add the inverse transform block 213 (i.e., the reconstructed residual block 213) to the prediction block 265 to obtain the reconstructed block 215 in the sample domain, e.g., to add sample values of the reconstructed residual block 213 to sample values of the prediction block 265.

Optionally, a buffer unit 216, e.g. a line buffer 216 (or simply "buffer" 216), is used to buffer or store the reconstructed block 215 and the corresponding sample values for e.g. intra prediction. In other embodiments, the encoder may be configured to use the unfiltered reconstructed block and/or the corresponding sample values stored in the buffer unit 216 for any kind of estimation and/or prediction, such as intra prediction.

For example, embodiments of encoder 20 may be configured such that buffer unit 216 is used not only to store reconstructed blocks 215 for intra prediction 254, but also for loop filter unit 220 (not shown in fig. 2), and/or such that buffer unit 216 and decoded picture buffer unit 230 form one buffer, for example. Other embodiments may be used to use the filtered block 221 and/or blocks or samples (neither shown in fig. 2) from the decoded picture buffer 230 as an input or basis for the intra prediction 254.

The loop filter unit 220 (or simply "loop filter" 220) is used to filter the reconstructed block 215 to obtain a filtered block 221, which facilitates pixel transitions or improves video quality. Loop filter unit 220 is intended to represent one or more loop filters, such as deblocking filters, sample-adaptive offset (SAO) filters, or other filters, such as bilateral filters, adaptive loop filters (adaptive loop filter, ALF), or sharpening or smoothing filters, or collaborative filters. Although loop filter unit 220 is shown in fig. 2 as an in-loop filter, in other configurations loop filter unit 220 may be implemented as a post-loop filter. The filtered block 221 may also be referred to as a filtered reconstructed block 221. Decoded picture buffer 230 may store the reconstructed encoded block after loop filter unit 220 performs a filtering operation on the reconstructed encoded block.

Embodiments of encoder 20 (and correspondingly loop filter unit 220) may be configured to output loop filter parameters (e.g., sample adaptive offset information), e.g., directly or after entropy encoding by entropy encoding unit 270 or any other entropy encoding unit, e.g., such that decoder 30 may receive and apply the same loop filter parameters for decoding.

Decoded picture buffer (decoded picture buffer, DPB) 230 may be a reference picture memory that stores reference picture data for use by encoder 20 in encoding video data. DPB 230 may be formed of any of a variety of memory devices, such as dynamic random access memory (dynamic random access memory, DRAM) (including Synchronous DRAM (SDRAM), magnetoresistive RAM (MRAM), resistive RAM (RRAM)), or other types of memory devices. DPB 230 and buffer 216 may be provided by the same memory device or separate memory devices. In a certain example, a decoded picture buffer (decoded picture buffer, DPB) 230 is used to store the filtered block 221. The decoded picture buffer 230 may further be used to store the same current picture or other previously filtered blocks, e.g., previously reconstructed and filtered blocks 221, of different pictures, e.g., previously reconstructed pictures, and may provide complete previously reconstructed, i.e., decoded pictures (and corresponding reference blocks and samples) and/or partially reconstructed current pictures (and corresponding reference blocks and samples), e.g., for inter prediction. In a certain example, if the reconstructed block 215 is reconstructed without in-loop filtering, the decoded picture buffer (decoded picture buffer, DPB) 230 is used to store the reconstructed block 215.

The prediction processing unit 260, also referred to as block prediction processing unit 260, is adapted to receive or obtain image blocks 203 (current image blocks 203 of a current picture 201) and reconstructed slice data, e.g. reference samples of the same (current) picture from the buffer 216 and/or reference picture data 231 of one or more previously decoded pictures from the decoded picture buffer 230, and to process such data for prediction, i.e. to provide a prediction block 265, which may be an inter-predicted block 245 or an intra-predicted block 255.

The mode selection unit 262 may be used to select a prediction mode (e.g., intra or inter prediction mode) and/or a corresponding prediction block 245 or 255 used as the prediction block 265 to calculate the residual block 205 and reconstruct the reconstructed block 215.

Embodiments of mode selection unit 262 may be used to select the prediction mode (e.g., from those supported by prediction processing unit 260) that provides the best match or minimum residual (minimum residual meaning better compression in transmission or storage), or that provides the minimum signaling overhead (minimum signaling overhead meaning better compression in transmission or storage), or both. The mode selection unit 262 may be adapted to determine a prediction mode based on a rate-distortion optimization (rate distortion optimization, RDO), i.e. to select the prediction mode that provides the least rate-distortion optimization, or to select a prediction mode for which the associated rate-distortion at least meets a prediction mode selection criterion.

The prediction processing performed by an instance of encoder 20 (e.g., by prediction processing unit 260) and the mode selection performed (e.g., by mode selection unit 262) will be explained in detail below.

As described above, the encoder 20 is configured to determine or select the best or optimal prediction mode from a (predetermined) set of prediction modes. The set of prediction modes may include, for example, intra prediction modes and/or inter prediction modes.

The set of intra prediction modes may include 35 different intra prediction modes, for example, a non-directional mode such as a DC (or mean) mode and a planar mode, or a directional mode as defined in h.265, or 67 different intra prediction modes, for example, a non-directional mode such as a DC (or mean) mode and a planar mode, or a directional mode as defined in h.266 under development.

In a possible implementation, the set of inter prediction modes depends on the available reference pictures (i.e. at least part of the decoded pictures stored in the DBP 230 as described above, for example) and other inter prediction parameters, e.g. on whether the entire reference picture is used or only a part of the reference picture is used, e.g. a search window area surrounding an area of the current block, to search for the best matching reference block, and/or on whether pixel interpolation like half-pixel and/or quarter-pixel interpolation is applied, e.g. the set of inter prediction modes may comprise advanced motion vector (Advanced Motion Vector Prediction, AMVP) mode and fusion (merge) mode, for example. In particular implementations, the set of inter prediction modes may include an improved control point-based AMVP mode of an embodiment of the present application, and an improved control point-based merge mode. In one example, intra-prediction unit 254 may be used to perform any combination of the inter-prediction techniques described below.

In addition to the above prediction modes, the present embodiments may also apply skip (skip) modes and/or direct modes.

The prediction processing unit 260 may be further operative to partition the image block 203 into smaller block partitions or sub-blocks, for example, by iteratively using a quad-tree (QT) partition, a binary-tree (BT) partition, or a ternary-tree (TT) partition, or any combination thereof, and to perform prediction for each of the block partitions or sub-blocks, for example, wherein the mode selection includes selecting a tree structure of the partitioned image block 203 and selecting a prediction mode applied to each of the block partitions or sub-blocks.

The inter prediction unit 244 may include a motion estimation (motion estimation, ME) unit (not shown in fig. 2) and a motion compensation (motion compensation, MC) unit (not shown in fig. 2). The motion estimation unit is used to receive or obtain a picture image block 203 (current picture image block 203 of current picture 201) and a decoded picture 231, or at least one or more previously reconstructed blocks, e.g. reconstructed blocks of one or more other/different previously decoded pictures 231, for motion estimation. For example, the video sequence may include a current picture and a previously decoded picture 31, or in other words, the current picture and the previously decoded picture 31 may be part of, or form, a sequence of pictures that form the video sequence.

For example, encoder 20 may be configured to select a reference block from a plurality of reference blocks of the same or different pictures of a plurality of other pictures, and provide the reference picture and/or an offset (spatial offset) between a position (X, Y coordinates) of the reference block and a position of a current block to a motion estimation unit (not shown in fig. 2) as an inter prediction parameter. This offset is also called Motion Vector (MV).

The motion compensation unit is used to acquire inter prediction parameters and perform inter prediction based on or using the inter prediction parameters to acquire the inter prediction block 245. The motion compensation performed by the motion compensation unit (not shown in fig. 2) may involve fetching or generating a prediction block based on motion/block vectors determined by motion estimation (possibly performing interpolation of sub-pixel accuracy). Interpolation filtering may generate additional pixel samples from known pixel samples, potentially increasing the number of candidate prediction blocks available for encoding a picture block. Upon receiving the motion vector for the PU of the current picture block, motion compensation unit 246 may locate the prediction block to which the motion vector points in a reference picture list. Motion compensation unit 246 may also generate syntax elements associated with the blocks and video slices for use by decoder 30 in decoding the picture blocks of the video slices.

Specifically, the inter prediction unit 244 may transmit a syntax element including inter prediction parameters (e.g., indication information of an inter prediction mode selected for current block prediction after traversing a plurality of inter prediction modes) to the entropy encoding unit 270. In a possible application scenario, if the inter prediction mode is only one, the inter prediction parameter may not be carried in the syntax element, and the decoding end 30 may directly use the default prediction mode for decoding. It is appreciated that the inter prediction unit 244 may be used to perform any combination of inter prediction techniques.

The intra prediction unit 254 is used to obtain, for example, a picture block 203 (current picture block) that receives the same picture and one or more previously reconstructed blocks, for example, reconstructed neighboring blocks, for intra estimation. For example, encoder 20 may be configured to select an intra-prediction mode from a plurality of (predetermined) intra-prediction modes.

Embodiments of encoder 20 may be used to select an intra-prediction mode based on optimization criteria, such as based on a minimum residual (e.g., the intra-prediction mode that provides a prediction block 255 most similar to current picture block 203) or minimum rate distortion.

The intra prediction unit 254 is further adapted to determine an intra prediction block 255 based on intra prediction parameters like the selected intra prediction mode. In any case, after the intra-prediction mode for the block is selected, the intra-prediction unit 254 is also configured to provide the intra-prediction parameters, i.e., information indicating the selected intra-prediction mode for the block, to the entropy encoding unit 270. In one example, intra-prediction unit 254 may be used to perform any combination of intra-prediction techniques.

Specifically, the intra-prediction unit 254 may transmit a syntax element including an intra-prediction parameter (such as indication information of an intra-prediction mode selected for the current block prediction after traversing a plurality of intra-prediction modes) to the entropy encoding unit 270. In a possible application scenario, if there is only one intra prediction mode, the intra prediction parameter may not be carried in the syntax element, and the decoding end 30 may directly use the default prediction mode for decoding.

The entropy encoding unit 270 is used to encode entropy encoding algorithms or schemes, such as a variable length coding (variable length coding, VLC) scheme, a Context Adaptive VLC (CAVLC) scheme, an arithmetic coding scheme, a context adaptive binary arithmetic coding (context adaptive binary arithmetic coding, CABAC), a syntax-based context adaptive binary arithmetic coding (syntax-based context-adaptive binary arithmetic coding,

SBAC), probability interval partition entropy (probability interval partitioning entropy, PIPE) coding, or other entropy coding methods or techniques are applied to a single or all of quantized residual coefficients 209, inter-prediction parameters, intra-prediction parameters, and/or loop filter parameters (or not applied) to obtain encoded picture data 21 that may be output through output 272 in the form of, for example, encoded bitstream 21. The encoded bitstream may be transmitted to video decoder 30 or archived for later transmission or retrieval by video decoder 30. Entropy encoding unit 270 may also be used to entropy encode other syntax elements of the current video slice being encoded.

Other structural variations of video encoder 20 may be used to encode the video stream. For example, the non-transform based encoder 20 may directly quantize the residual signal without a transform processing unit 206 for certain blocks or frames. In another embodiment, encoder 20 may have quantization unit 208 and inverse quantization unit 210 combined into a single unit.

In particular, in the present embodiment, the encoder 20 may be used to implement the optimization processing method for fusing motion vector difference techniques described in the embodiments below.

It should be appreciated that other structural variations of video encoder 20 may be used to encode the video stream. For example, for some image blocks or image frames, video encoder 20 may directly quantize the residual signal without processing by transform processing unit 206, and accordingly without processing by inverse transform processing unit 212; alternatively, for some image blocks or image frames, video encoder 20 does not generate residual data and accordingly does not need to be processed by transform processing unit 206, quantization unit 208, inverse quantization unit 210, and inverse transform processing unit 212; alternatively, video encoder 20 may store the reconstructed image block directly as a reference block without processing via filter 220; alternatively, quantization unit 208 and inverse quantization unit 210 in video encoder 20 may be combined together. The loop filter 220 is optional, and in the case of lossless compression encoding, the transform processing unit 206, quantization unit 208, inverse quantization unit 210, and inverse transform processing unit 212 are optional. It should be appreciated that inter-prediction unit 244 and intra-prediction unit 254 may be selectively enabled depending on the different application scenarios.

Referring to fig. 3, fig. 3 shows a schematic/conceptual block diagram of an example of a decoder 30 for implementing an embodiment of the present application. Video decoder 30 is operative to receive encoded picture data (e.g., encoded bitstream) 21, e.g., encoded by encoder 20, to obtain decoded picture 231. During the decoding process, video decoder 30 receives video data, such as an encoded video bitstream representing picture blocks of an encoded video slice and associated syntax elements, from video encoder 20.

In the example of fig. 3, decoder 30 includes entropy decoding unit 304, inverse quantization unit 310, inverse transform processing unit 312, reconstruction unit 314 (e.g., summer 314), buffer 316, loop filter 320, decoded picture buffer 330, and prediction processing unit 360. The prediction processing unit 360 may include an inter prediction unit 344, an intra prediction unit 354, and a mode selection unit 362. In some examples, video decoder 30 may perform a decoding pass that is substantially reciprocal to the encoding pass described with reference to video encoder 20 of fig. 2.

Entropy decoding unit 304 is used to perform entropy decoding on encoded picture data 21 to obtain, for example, quantized coefficients 309 and/or decoded encoding parameters (not shown in fig. 3), e.g., any or all of inter-prediction, intra-prediction parameters, loop filter parameters, and/or other syntax elements (decoded). Entropy decoding unit 304 is further configured to forward inter-prediction parameters, intra-prediction parameters, and/or other syntax elements to prediction processing unit 360. Video decoder 30 may receive syntax elements at the video stripe level and/or the video block level.

Inverse quantization unit 310 may be functionally identical to inverse quantization unit 110, inverse transform processing unit 312 may be functionally identical to inverse transform processing unit 212, reconstruction unit 314 may be functionally identical to reconstruction unit 214, buffer 316 may be functionally identical to buffer 216, loop filter 320 may be functionally identical to loop filter 220, and decoded picture buffer 330 may be functionally identical to decoded picture buffer 230.

The prediction processing unit 360 may include an inter prediction unit 344 and an intra prediction unit 354, where the inter prediction unit 344 may be similar in function to the inter prediction unit 244 and the intra prediction unit 354 may be similar in function to the intra prediction unit 254. The prediction processing unit 360 is typically used to perform block prediction and/or to obtain a prediction block 365 from the encoded data 21, as well as to receive or obtain prediction related parameters and/or information about the selected prediction mode (explicitly or implicitly) from, for example, the entropy decoding unit 304.

When a video slice is encoded as an intra-coded (I) slice, the intra-prediction unit 354 of the prediction processing unit 360 is used to generate a prediction block 365 for a picture block of the current video slice based on the signaled intra-prediction mode and data from a previously decoded block of the current frame or picture. When a video frame is encoded as an inter-coded (i.e., B or P) slice, an inter-prediction unit 344 (e.g., a motion compensation unit) of prediction processing unit 360 is used to generate a prediction block 365 for a video block of the current video slice based on the motion vector and other syntax elements received from entropy decoding unit 304. For inter prediction, a prediction block may be generated from one reference picture within one reference picture list. Video decoder 30 may construct a reference frame list based on the reference pictures stored in DPB330 using default construction techniques: list 0 and list 1.

The prediction processing unit 360 is configured to determine prediction information for a video block of a current video slice by parsing the motion vector and other syntax elements, and generate a prediction block for the current video block being decoded using the prediction information. In an example of the present application, prediction processing unit 360 uses some syntax elements received to determine a prediction mode (e.g., intra or inter prediction) for encoding video blocks of a video slice, an inter prediction slice type (e.g., B slice, P slice, or GPB slice), construction information for one or more of the reference picture lists of the slice, motion vectors for each inter-encoded video block of the slice, inter prediction state for each inter-encoded video block of the slice, and other information to decode video blocks of the current video slice. In another example of the present disclosure, the syntax elements received by video decoder 30 from the bitstream include syntax elements received in one or more of an adaptive parameter set (adaptive parameter set, APS), a sequence parameter set (sequence parameter set, SPS), a picture parameter set (picture parameter set, PPS), or a slice header.

Inverse quantization unit 310 may be used to inverse quantize (i.e., inverse quantize) the quantized transform coefficients provided in the bitstream and decoded by entropy decoding unit 304. The inverse quantization process may include using quantization parameters calculated by video encoder 20 for each video block in a video stripe to determine the degree of quantization that should be applied and likewise the degree of inverse quantization that should be applied.

The inverse transform processing unit 312 is configured to apply an inverse transform (e.g., an inverse DCT, an inverse integer transform, or a conceptually similar inverse transform process) to the transform coefficients in order to generate a residual block in the pixel domain.

A reconstruction unit 314 (e.g., a summer 314) is used to add the inverse transform block 313 (i.e., the reconstructed residual block 313) to the prediction block 365 to obtain a reconstructed block 315 in the sample domain, e.g., by adding sample values of the reconstructed residual block 313 to sample values of the prediction block 365.

Loop filter unit 320 is used (during or after the encoding cycle) to filter reconstructed block 315 to obtain filtered block 321, to smooth pixel transitions or improve video quality. In one example, loop filter unit 320 may be used to perform any combination of the filtering techniques described below. Loop filter unit 320 is intended to represent one or more loop filters, such as a deblocking filter, a sample-adaptive offset (SAO) filter, or other filters, such as a bilateral filter, an adaptive loop filter (adaptive loop filter, ALF), or a sharpening or smoothing filter, or a collaborative filter. Although loop filter unit 320 is shown in fig. 3 as an in-loop filter, in other configurations loop filter unit 320 may be implemented as a post-loop filter.

The decoded video blocks 321 in a given frame or picture are then stored in a decoded picture buffer 330 that stores reference pictures for subsequent motion compensation.

Decoder 30 is for outputting decoded picture 31, e.g., via output 332, for presentation to a user or for viewing by a user.

Other variations of video decoder 30 may be used to decode the compressed bitstream. For example, decoder 30 may generate the output video stream without loop filter unit 320. For example, the non-transform based decoder 30 may directly inverse quantize the residual signal without an inverse transform processing unit 312 for certain blocks or frames. In another embodiment, the video decoder 30 may have an inverse quantization unit 310 and an inverse transform processing unit 312 combined into a single unit.

Specifically, in the embodiment of the present application, the decoder 30 is configured to implement the optimization processing method for fusing motion vector difference techniques described in the later embodiments.

It should be appreciated that other structural variations of video decoder 30 may be used to decode the encoded video bitstream. For example, video decoder 30 may generate an output video stream without processing by filter 320; alternatively, for some image blocks or image frames, the entropy decoding unit 304 of the video decoder 30 does not decode quantized coefficients, and accordingly does not need to be processed by the inverse quantization unit 310 and the inverse transform processing unit 312. Loop filter 320 is optional; and for the case of lossless compression, the inverse quantization unit 310 and the inverse transform processing unit 312 are optional. It should be appreciated that the inter prediction unit and the intra prediction unit may be selectively enabled according to different application scenarios.

It should be understood that, in the encoder 20 and the decoder 30 of the present application, the processing result for a certain link may be further processed and then output to a next link, for example, after the links such as interpolation filtering, motion vector derivation or loop filtering, the processing result for the corresponding link is further processed by performing operations such as Clip or shift.

For example, the motion vector of the control point of the current image block derived from the motion vector of the neighboring affine encoded block, or the motion vector of the sub-block of the current image block derived therefrom, may be further processed, which is not limited in this application. For example, the range of motion vectors is constrained to be within a certain bit width. Assuming that the bit width of the allowed motion vector is bitDepth, the range of motion vectors is-2 ^bitDepth-1 ～2 ^bitDepth-1 -1. If the bitDepth is 16, the value range is-32768-32767. If the bitDepth is 18, the value range is-131072 ～ 131071. For another example, the values of the motion vectors (e.g., motion vectors MV of four 4 x 4 sub-blocks within one 8x8 image block) are constrained such that the maximum difference between the integer parts of the four 4 x 4 sub-blocks MV does not exceed N pixels, e.g., does not exceed one pixel.

The constraint can be made within a certain positioning width by the following two ways:

mode 1, the high order overflow of the motion vector is removed:

ux＝(vx+2 ^bitDepth )％2 ^bitDepth

vx＝(ux≥2 ^bitDepth-1 )？(ux-2 ^bitDepth ):ux

uy＝(vy+2 ^bitDepth )％2 ^bitDepth

vy＝(uy≥2 ^bitDepth-1 )？(uy-2 ^bitDepth ):uy

wherein vx is a horizontal component of a motion vector of an image block or a sub-block of the image block, vy is a vertical component of a motion vector of an image block or a sub-block of the image block, ux and uy are intermediate values; bitDepth represents the bit width.

For example vx has a value of-32769 and 32767 by the above formula. Because in the computer the values are stored in the form of binary complements, -32769 has a binary complement 1,0111,1111,1111,1111 (17 bits), the computer discards the high order bits for the overflow treatment, and vx has a value 0111,1111,1111,1111 and 32767, consistent with the result obtained by the formula treatment.

Method 2, clipping the motion vector as shown in the following formula:

vx＝Clip3(-2 ^bitDepth-1 ,2 ^bitDepth-1 -1,vx)

vy＝Clip3(-2 ^bitDepth-1 ,2 ^bitDepth-1 -1,vy)

where vx is the horizontal component of the motion vector of an image block or a sub-block of the image block and vy is the vertical component of the motion vector of an image block or a sub-block of the image block; wherein x, y and z correspond to three input values of MV clamping process Clip3, respectively, the definition of Clip3 is that the value of z is clamped between intervals [ x, y ]:

Referring to fig. 4, fig. 4 is a schematic structural diagram of a video decoding apparatus 400 (e.g., a video encoding apparatus 400 or a video decoding apparatus 400) provided in an embodiment of the present application. The video coding apparatus 400 is adapted to implement the embodiments described herein. In one embodiment, video coding device 400 may be a video decoder (e.g., decoder 30 of fig. 1A) or a video encoder (e.g., encoder 20 of fig. 1A). In another embodiment, video coding apparatus 400 may be one or more of the components described above in decoder 30 of fig. 1A or encoder 20 of fig. 1A.

The video coding apparatus 400 includes: an ingress port 410 and a receiving unit (Rx) 420 for receiving data, a processor, logic unit or Central Processing Unit (CPU) 430 for processing data, a transmitter unit (Tx) 440 and an egress port 450 for transmitting data, and a memory 460 for storing data. The video decoding apparatus 400 may further include a photoelectric conversion component and an electro-optical (EO) component coupled to the inlet port 410, the receiver unit 420, the transmitter unit 440, and the outlet port 450 for the outlet or inlet of optical or electrical signals.

The processor 430 is implemented in hardware and software. Processor 430 may be implemented as one or more CPU chips, cores (e.g., multi-core processors), FPGAs, ASICs, and DSPs. Processor 430 is in communication with inlet port 410, receiver unit 420, transmitter unit 440, outlet port 450, and memory 460. The processor 430 includes a coding module 470 (e.g., an encoding module 470 or a decoding module 470). The encoding/decoding module 470 implements embodiments disclosed herein to implement the chroma block prediction methods provided by embodiments of the present application. For example, the encoding/decoding module 470 implements, processes, or provides various encoding operations. Thus, substantial improvements are provided to the functionality of the video coding device 400 by the encoding/decoding module 470 and affect the transition of the video coding device 400 to different states. Alternatively, the encoding/decoding module 470 is implemented in instructions stored in the memory 460 and executed by the processor 430.

Memory 460 includes one or more disks, tape drives, and solid state drives, and may be used as an overflow data storage device for storing programs when selectively executing such programs, as well as storing instructions and data read during program execution. Memory 460 may be volatile and/or nonvolatile and may be Read Only Memory (ROM), random Access Memory (RAM), random access memory (TCAM) and/or Static Random Access Memory (SRAM).

Referring to fig. 5, fig. 5 is a simplified block diagram of an apparatus 500 that may be used as either or both of the source device 12 and the destination device 14 in fig. 1A, according to an example embodiment. The apparatus 500 may implement the techniques of this application. In other words, fig. 5 is a schematic block diagram of one implementation of an encoding device or decoding device (simply referred to as decoding device 500) of an embodiment of the present application. The decoding device 500 may include, among other things, a processor 510, a memory 530, and a bus system 550. The processor is connected with the memory through the bus system, the memory is used for storing instructions, and the processor is used for executing the instructions stored by the memory. The memory of the decoding device stores program code, and the processor may invoke the program code stored in the memory to perform the various video encoding or decoding methods described herein. To avoid repetition, a detailed description is not provided herein.

In the present embodiment, the processor 510 may be a central processing unit (Central Processing Unit, abbreviated as "CPU"), and the processor 510 may also be other general purpose processors, digital Signal Processors (DSPs), application Specific Integrated Circuits (ASICs), off-the-shelf programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The memory 530 may include a Read Only Memory (ROM) device or a Random Access Memory (RAM) device. Any other suitable type of storage device may also be used as memory 530. Memory 530 may include code and data 531 accessed by processor 510 using bus 550. The memory 530 may further include an operating system 533 and an application 535, the application 535 including at least one program that allows the processor 510 to perform the video encoding or decoding methods described herein (particularly the optimization processing methods described herein for the fused motion vector difference technique). For example, applications 535 may include applications 1 through N, which further include video encoding or decoding applications (simply video coding applications) that perform the video encoding or decoding methods described herein.

The bus system 550 may include a power bus, a control bus, a status signal bus, and the like in addition to a data bus. For clarity of illustration, the various buses are labeled in the figure as bus system 550.

Optionally, the decoding device 500 may also include one or more output devices, such as a display 570. In one example, the display 570 may be a touch sensitive display that incorporates a display with a touch sensitive unit operable to sense touch input. A display 570 may be connected to processor 510 via bus 550.

The following details the scheme of the embodiments of the present application:

among video coding and decoding techniques, a merge (merge) mode is one of techniques capable of effectively improving inter-frame coding efficiency. For the merge mode, the encoding end firstly constructs a candidate motion vector list through the motion information of the coded image blocks adjacent to the current image block in the space domain or the time domain, takes the candidate motion information with the minimum rate distortion Cost (RD Cost) in the candidate motion vector list as a motion vector predicted value (motion vector predictor, MVP) of the current image block, and then transmits an index value (marked as merge index) of the position of the optimal candidate motion information in the candidate motion vector list to the decoding end.

The positions of the adjacent image blocks and the traversing sequence thereof are predefined. The RD Cost can be calculated by the following formula (1), where J represents the RD Cost, SAD is the sum of absolute errors (sum of absolute differences, SAD) between the predicted pixel value obtained after motion estimation using the candidate motion vector predicted value, R represents the code rate, and λ represents the lagrangian multiplier.

J＝SAD+λR (1)

Further, the encoding end can perform motion search in a neighborhood with the MVP as the center to obtain an actual motion vector of the current image block, and then the encoding end transmits a difference (i.e., residual) between the MVP and the actual motion vector to the decoding end.

For example, fig. 6 is a schematic diagram of the spatial domain and the temporal domain of the current image block in the embodiment of the present application, referring to fig. 6, the spatial domain candidate motion information is from 5 spatially neighboring blocks (A0, A1, B0, B1 and B2), and if the neighboring image block is not available (i.e. the neighboring image block does not exist, the neighboring image block is not encoded, or the prediction mode adopted by the neighboring image block is not the inter prediction mode), the motion information of the neighboring image block is not added to the candidate motion vector list of the current image block. The time domain candidate motion information of the current image block is obtained by scaling Motion Vectors (MVs) of image blocks at corresponding positions in a reference frame according to sequence counts (picture order count, POCs) of the reference frame and the current frame, firstly judging whether the image block at a T position in the reference frame is available or not, and if not, selecting the image block at a C position in the reference frame.

Further, there is a special mode in the merge mode, that is, the skip mode, where the skip mode is different from the merge mode in that there is no residual error in transmission, and only the merge index is transmitted, where the merge index is used to indicate the best or target candidate motion information in the fusion candidate motion information list.

In either the merge mode or skip mode, the application has a TPM. Fig. 7 is a schematic diagram of a triangular prediction unit in an embodiment of the present application, and referring to fig. 7, a current image block is divided into two triangular prediction units, each of which selects a motion vector and a reference frame index from a unidirectional prediction candidate list. Then, one prediction value is obtained for each of the two triangular prediction units. Next, the pixels included in the hypotenuse region are weighted adaptively to obtain a predicted value. Finally, the transformation and quantization process is performed on the entire current image block.

Here, it should be noted that, fig. 8 is a schematic diagram of the partition manner of the triangular prediction unit in the embodiment of the present application, and referring to fig. 8 (1), the current image block is divided into two triangular prediction units according to the partition manner of upper left and lower right (i.e. partition from upper left to lower right), and referring to fig. 8 (2), the current image block is divided into two triangular prediction units according to the partition manner of upper right and lower left (i.e. partition from upper right to lower left).

In practice, the unidirectional prediction candidate list in the TPM may generally include 5 candidate prediction motion vectors. These candidate predicted motion vectors are from 7 surrounding neighboring image blocks (i.e., 5 spatial neighboring blocks, 2 temporal corresponding blocks) as shown in fig. 6. By searching for motion information of 7 neighboring image blocks and putting the motion information into a unidirectional prediction candidate list in order. If the number of candidates is less than 5, the supplemental motion vector 0 is added to the unidirectional prediction candidate list. When the encoding end performs encoding, a unidirectional prediction candidate list can be obtained in the above manner. Illustratively, forward predicted motion information in the unidirectional prediction candidate list is used to predict the pixel prediction value of one triangular prediction unit, and backward predicted motion information is used to predict the pixel prediction value of another triangular prediction unit. The encoding end selects the best motion vector by traversing.

After the encoding end completes the prediction of the two triangular prediction units, the encoding end carries out self-adaptive weighting on pixels included in the hypotenuse area so as to obtain the predicted value of the final current image block. For example, referring to the left image in FIG. 7, the predicted value of the pixel at the "2" position is 2/8 XP ₁ +6/8×P ₂ Wherein P is ₁ Representing the predicted value of the pixel in the upper right region of FIG. 7, P ₂ The predicted value of the pixel in the lower left region in fig. 7 is shown. Then, the two sets of predictor weighting parameters are as follows:

a first set of weighting parameters: {7/8,6/8,4/8,2/8,1/8} and {7/8,4/8,1/8} for luminance and chrominance points, respectively;

a second set of weighting parameters: {7/8,6/8,5/8,4/8,3/8,2/8,1/8} and {6/8,4/8,2/8}, for luminance and chrominance points, respectively.

Wherein a set of weighting parameters will be used for the codec implementation of the current image block. When the reference images of the two triangulation units differ or the difference between their motion vectors is greater than 16 pixels, another set of weighting parameters is selected.

Embodiments of the present application provide a processing method based on a TPM, which may be performed by the video encoder or the video decoder in the above embodiments.

Fig. 9 is a flowchart of a processing method based on a TPM according to an embodiment of the present application, and referring to fig. 9, the method includes:

s901: obtaining a first prediction parameter;

here, the above-described processing method may be performed by the above-described video encoder or video decoder. Then, the video encoder or video decoder described above may obtain the first prediction parameter by parsing the syntax element. The first prediction parameter is used for processing a preset video processing unit.

In the high-level syntax of the existing VVC draft, at present, a syntax structure mainly including a sequence level, a picture level and a tile group (tile group) level is included in addition to the CU level, and the sizes of video processing units corresponding to the respective levels are different, for example, the video processing unit at the sequence level includes a plurality of frame images, the video processing unit at the picture level may be divided into a plurality of tile groups, and the video processing unit at the tile group level may be divided into a plurality of CUs. In this embodiment of the present application, the preset video processing unit may include a tile group, a frame of image, or a video sequence, that is, the preset video processing unit may be an image block processed at a sequence level, an image level, or a tile group level.

In practical applications, the first prediction parameter may be a maximum number of candidate motion vector lists (e.g. MaxNumMergeCand) corresponding to the preset video processing unit (i.e. the current image block), and the maximum number of candidate motion vector lists may also be referred to as a maximum number of fusion MVP lists.

Then, the encoder or decoder may obtain the MaxNumMergeCand corresponding to the preset video processing unit by parsing the syntax element, such as six_minus_max_num_merge_cand, i.e. maxnummergecand=6-six_minus_max_num_merge_cand. Where six_minus_max_num_merge_cand is the difference between the maximum number of available fusion MVP lists corresponding to the current image block of 6.

The first prediction parameter may also be a TPM identifier corresponding to a preset video processing unit. Since in the embodiment of the present application, the preset video processing unit may be an image block processed at a sequence level, an image level, or a tile group level, then the TPM identifier corresponding to the preset video processing unit may be different according to the level at which the preset video processing unit is located. For example, if the preset video processing unit is an image block processed at a sequence level, the TPM identifier may be a seq_triple_enabled_flag; if the preset video processing unit is an image block processed at an image level, the TPM mark can be pic_triangle_enabled_flag; if the preset video processing unit is an image block processed at the tile group level, the TPM flag may be tile_triple_enabled_flag. Of course, the TPM identifier may also be other syntax elements, which are not specifically limited in the embodiments of the present application.

In the following embodiments, the preset video processing unit processes at a tile group (tile group) level, and the TPM is identified as a tile_triangle_enabled_flag for illustration.

It should be noted that, the encoding end may obtain the first prediction parameter by parsing a pre-configured syntax element, and the decoding end may obtain the first prediction parameter by parsing a syntax element in the bitstream.

S902: determining whether to allow processing of a plurality of CUs in a preset video processing unit by using the TPM according to the first prediction parameters;

wherein, the plurality of CUs in the preset video processing unit include CUs to be processed.

For both cases of the first prediction parameter described above, S902 may and is not limited to the following cases:

in the first case, the first prediction parameter is MaxNumMergeCand corresponding to the preset video processing unit.

Then, the encoding end or the decoding end may determine whether to allow processing of a plurality of CUs in the preset video processing unit using the TPM in the following manner.

Mode one:

at this time, at the encoding end or decoding end, S902 may include: the encoder or decoder compares the MaxNumMergeCand with a first threshold (th 1) to determine whether the CUs in the preset video processing unit allow processing using the TPM;

here, after the encoder or decoder obtains MaxNumMergeCand through S901, the MaxNumMergeCand is compared with th1, and at this time, th1 may be a positive integer, for example, th1 takes a value of 2, 3, 4, 5 or 6. If MaxNumMergeCand is more than or equal to th1, determining that the TPM is allowed to process a plurality of CUs in a preset video processing unit; if MaxNumMergeCand < th1, determining to prohibit processing of a plurality of CUs in the preset video processing unit by using the TPM.

It should be noted that, at the encoding end, the encoder compares MaxNumMergeCand with th1, if MaxNumMergeCand is greater than or equal to th1, the encoder may determine to allow the use of the TPM to process a plurality of CUs in the preset video processing unit; if MaxNumMergeCand < th1, the encoder may determine to prohibit processing of multiple CUs in the preset video processing unit using the TPM.

At the decoding end, the decoder compares MaxNumMergeCand with th1, and if MaxNumMergeCand is more than or equal to th1, the decoder can determine that the TPM is allowed to process a plurality of CUs in a preset video processing unit; if MaxNumMergeCand < th1, the decoder may determine to prohibit processing of multiple CUs in the preset video processing unit using the TPM.

Therefore, the encoding end and the decoding end can determine whether to process a plurality of CUs in the preset video processing unit by using TPM through MaxNumMergeCand, and then judgment of the preset video processing unit of the tile group level can be realized only by carrying the value information of MaxNumMergeCand in the transmission process of the code stream.

Further, after the encoder or the decoder determines whether to use the TPM to process the multiple CUs in the preset video processing unit, the TPM identifier, i.e., tile_triangle_enabled_flag, corresponding to the preset video processing unit in the syntax element may be assigned. For example, when processing is allowed for a plurality of CUs in a preset video processing unit using the TPM, the encoder or decoder may assign a tile_triangle_enabled_flag corresponding to the preset video processing unit to a first value, e.g., tile_triangle_enabled_flag=1; when the TPM is prohibited from processing the CUs in the preset video processing unit, the encoder or decoder may assign a tile_triangle_enabled_flag corresponding to the preset video processing unit to a second value, e.g., tile_triangle_enabled_flag=0. Here, the first value and the second value may also have other values, where the first value is different from the second value, and embodiments of the present application are not specifically limited.

In this way, after the encoder assigns the tile_triangle_enabled_flag corresponding to the preset video processing unit in the syntax element, the code stream may carry the value information of the tile_triangle_enabled_flag, so as to directly inform the decoding end how to process, and the decoding end may determine whether the preset video processing unit allows the TPM to process by analyzing the tile_triangle_enabled_flag.

Mode two:

at this time, at the encoding end, S902 may include: the encoder compares MaxNumMergeCand with a second threshold (th 2); if MaxNumMergeCand is more than or equal to th2, the encoder determines whether to allow the TPM to process a plurality of CUs in a preset video processing unit according to RD Cost; at this time, th2 may be a positive integer, for example, th2 takes a value of 2, 3, 4, 5 or 6.

At the decoding end, S902 may include: the decoder compares MaxNumMergeCand with th 2; if MaxNumMergeCand is greater than or equal to th2, the decoder parses the code stream to obtain tile_triple_enabled_flag corresponding to the preset video processing unit, for example, the following shows a part of syntax of the decoder:

if(MaxNumMergeCand≥th2)

tile_triangle_enabled_flag；

then, the decoder may determine whether to allow processing of the plurality of CUs in the preset video processing unit using the TPM according to the parsed value information of the tile_three_enabled_flag. When the value of the tile_triangle_enabled_flag is a first value, indicating that the TPM is allowed to be used for processing a plurality of CUs in a preset video processing unit; and if the value of the tile_triple_enabled_flag is the second value, indicating that the TPM is forbidden to process a plurality of CUs in the preset video processing unit. For example, if MaxNumMergeCand is greater than or equal to th2 and tile_triple_enabled_flag=1, the decoder determines that processing of multiple CUs in the preset video processing unit using the TPM is allowed; if MaxNumMergeCand is greater than or equal to th2 and tile_triple_enabled_flag=0, the decoder determines to prohibit processing of the plurality of CUs in the preset video processing unit using the TPM.

Further, if MaxNumMergeCand < th2, the decoder determines whether to allow processing of a plurality of CUs in the preset video processing unit using the TPM according to a preset value (i.e., default value) of tile_triangle_enabled_flag. In this case, the decoder may determine whether to allow processing of the plurality of CUs in the preset video processing unit using the TPM according to a preset value of tile_triple_enabled_flag pre-agreed with the encoder, for example, when a default value of tile_triple_enabled_flag is 1, it is determined that processing of the plurality of CUs in the preset video processing unit using the TPM is allowed, and when a default value of tile_triple_enabled_flag is 0, it is determined that processing of the plurality of CUs in the preset video processing unit using the TPM is prohibited.

In practical applications, there is a special case that if the decoder does not parse the tile_three_enabled_flag from the code stream, the decoder sets the preset value of the tile_three_enabled_flag to a second value, for example, sets tile_three_enabled_flag=0, so that when the decoder is in MaxNumMergeCand < th2, it can be determined whether to allow processing of multiple CUs in the preset video processing unit using the TPM according to the preset value of the tile_three_enabled_flag.

In the second case, the first prediction parameter is a tile_triangle_enabled_flag corresponding to the preset video processing unit.

Then, the decoding end may determine whether to allow processing of the plurality of CUs in the preset video processing unit using the TPM in the following manner.

At this time, at the decoding end, S902 may include: determining whether to allow processing of a plurality of CUs in a preset video processing unit by using a TPM according to the indication of the tile_triple_enabled_flag; when the value of the tile_triangle_enabled_flag is a first value, determining that the TPM is allowed to be used for processing a plurality of CUs in a preset video processing unit; and when the value of the tile_triangle_enabled_flag is the second value, prohibiting the TPM from processing a plurality of CUs in the preset video processing unit. For example, when tile_three_enabled_flag=1, the decoder determines that processing of a plurality of CUs in a preset video processing unit using the TPM is permitted; when tile_triple_enabled_flag=0, the decoder determines to prohibit processing of a plurality of CUs in the preset video processing unit using the TPM.

In the first method of the first case, the encoding end determines whether to allow the use of the TPM to process the multiple CUs in the preset video processing unit according to the MaxNumMergeCand, assigns a value to the tile_triple_enabled_flag, and carries the tile_triple_enabled_flag in the code stream to be transmitted to the decoding end, where the decoding end may parse the code stream to obtain the tile_triple_enabled_flag, and determine whether to allow the use of the TPM to process the multiple CUs in the preset video processing unit according to the value of the tile_triple_enabled_flag.

In the above method, the TPM identifier may also be a TPM identifier (seq_triple_enabled_flag) corresponding to a sequence level or a TPM identifier (pic_triple_enabled_flag) corresponding to an image level, that is, the preset video processing unit may be an image block of any level of the sequence level, the image level, and the tile group level, and the embodiment of the present application is not limited specifically as to which image level corresponds to the TPM identifier of the level.

S903: and when the TPM is forbidden to process the plurality of CUs in the preset video processing unit, the TPM is forbidden to process the CUs to be processed.

Here, if the encoder or the decoder determines that the processing of the CUs in the preset video processing unit using the TPM is prohibited, the encoder or the decoder may directly determine that the processing of the CUs to be processed using the TPM is prohibited. Thus, in some cases, such as when the maximum number of candidate motion vector lists is greater than 1, processing using a TPM does not provide additional performance of image processing, the encoder or decoder may directly shut down TPM processing at higher image levels than the CU level, at the sequence level, at the image level, or at the tile group level, to increase the efficiency of encoding and decoding.

Further, for the CU to be processed, when the encoder determines that the processing of the CU to be processed using the TPM is prohibited, the encoder may omit encoding of the TPM syntax information of the CU to be processed, or the encoder may set the TPM syntax information of the CU to be processed to a preset value, so that the TPM syntax information is not required to be carried in the code stream, so as to save the bit number of the code stream; accordingly, when determining that the TPM is prohibited to process the CU to be processed, the decoder can determine that the code stream does not contain TPM grammar information of the CU to be processed, and further does not analyze the TPM grammar information of the CU to be processed in the code stream, so that decoding complexity is reduced.

In the embodiment of the application, the TPM grammar information of the CU to be processed is used for constructing the predicted value obtained by the CU to be processed based on the TPM. The TPM syntax information may include: the merge_triangule_flag (used to indicate whether the current CU uses the triangle prediction unit mode), the merge_triangule_split_dir (used to indicate the partition direction of the TPM), the merge_triangule_idx0 (used to indicate that the TPM is based on the first fusion candidate index value in the motion compensation candidate list), and the merge_triangule_idx1 (used to indicate that the TPM is based on the second fusion candidate index value in the motion compensation candidate list). Of course, the TPM syntax information of the CU to be processed may also include other information, which is not specifically limited in the embodiment of the present application.

S904: when the TPM is allowed to process a plurality of CUs in the preset video processing unit, determining whether to process the CUs to be processed by using the TPM according to the second prediction parameters.

Here, if the encoder or decoder determines that the processing of a plurality of CUs in the preset video processing unit is permitted using the TPM, the encoder or decoder may determine whether to process the CUs to be processed using the TPM one by one. That is, if it is determined at a high level (such as any one of a sequence level, an image level, or a tile group level) that processing is permitted for a plurality of CUs in a preset video processing unit using a TPM, at this time, an encoder or a decoder cannot directly determine that all CUs to be processed are processed using the TPM, but further needs to determine whether or not each of the CUs to be processed is processed using the TPM one by one. Then, the encoder may determine whether to process the CU to be processed using the TPM according to the second prediction parameter (i.e., maxNumMergeCand corresponding to the CU) one by one according to the first and/or second methods in the first case of S902. Accordingly, the decoding end may determine whether to process the CU to be processed using the TPM according to the second prediction parameter (i.e., the MaxNumMergeCand or the merge_trie_flag corresponding to the CU) one by one according to the method in the first case and/or the second case. The principle of the specific determination process is similar to that of step S902, and will not be described here again.

Illustratively, the decoder is shown below for part of the syntax of the CU to be processed:

merge_triangle_flag[x0][y0]；

if(merge_triangle_flag[x0][y0]){

merge_triangle_split_dir[x0][y0]；

merge_triangle_idx0[x0][y0]；

merge_triangle_idx1[x0][y0]；

}else if(MaxNumMergeCand>1)；

merge_idx[x0][y0]；

in the embodiment of the application, when determining that the processing at the sequence level, the image level or the block group level is prohibited to use the TPM to process the plurality of CUs in the preset video image unit according to the maximum number of the candidate motion vector list, it may be directly determined that the processing at the TPM to be processed in the plurality of CUs is prohibited to be used, thereby reducing complexity of encoding and decoding and improving encoding and decoding efficiency.

Based on the same inventive concept as the above method, the present application also provides an inter prediction apparatus, which can be applied to the above decoder 30.

Fig. 10 is a schematic structural diagram of an inter prediction apparatus in an embodiment of the present application, and referring to fig. 10, the inter prediction apparatus 1000 may include: the parsing module 1001 is configured to parse the code stream to obtain a first prediction parameter, where the first prediction parameter is used to process a preset video processing unit; a determining module 1002, configured to determine whether to allow processing of a plurality of coding units CU in a preset video processing unit using a triangular prediction unit mode TPM according to a first prediction parameter, where the plurality of CUs include CUs to be processed; and when the TPM is forbidden to process the plurality of CUs in the preset video processing unit, the TPM is forbidden to process the CUs to be processed.

In a possible implementation, the preset video processing unit comprises a slice group, a frame of images or a video sequence.

In a possible implementation manner, the determining module 1002 is further configured to, when processing is allowed to be performed on a plurality of CUs in the preset video processing unit using the TPM, parse and obtain a second prediction parameter from the code stream, where the second prediction parameter is used to process the CU to be processed; and determining whether to process the CU to be processed by using the TPM according to the second prediction parameters.

In a possible implementation manner, the determining module 1002 is specifically configured to determine that the TPM is allowed to process the plurality of CUs in the preset video processing unit when the value of the first prediction parameter is the first value; and when the value of the first prediction parameter is a second value, determining to prohibit processing of a plurality of CUs in the preset video processing unit by using the TPM, wherein the first value is different from the second value.

In one possible implementation, when the first prediction parameter is the maximum number of candidate motion vector lists corresponding to the preset video processing unit, the determining module 1002 is specifically configured to compare the maximum number with a first threshold, and determine whether to allow processing of the multiple CUs in the preset video processing unit using the TPM; wherein when the maximum number is greater than or equal to a first threshold, determining that the TPM is allowed to be used for processing a plurality of CUs in the preset video processing unit; and when the maximum number is smaller than the first threshold value, prohibiting the TPM from being used for processing the plurality of CUs in the preset video processing unit.

In one possible implementation, referring to fig. 10, shown by a dashed line, the apparatus 1000 further includes: an optimizing module 1003, configured to assign, when processing is allowed to be performed on a plurality of CUs in a preset video processing unit by using a TPM, a TPM identifier corresponding to the preset video processing unit to a first value; when the TPM is forbidden to process the plurality of CUs in the preset video processing unit, the TPM identification is assigned to a second value, and the first value is different from the second value.

In one possible implementation manner, when the first prediction parameter is the maximum number of candidate motion vector lists corresponding to the preset video processing unit, the determining module 1002 is specifically configured to compare the maximum number with the second threshold; when the maximum number is greater than or equal to a second threshold value, analyzing and obtaining TPM (tire platform module) identifiers corresponding to the preset video processing units from the code stream, and determining whether to allow the TPM to process a plurality of CUs in the preset video processing units according to the values of the TPM identifiers; when the value of the TPM identifier is a first value, allowing the TPM to process a plurality of CUs in a preset video processing unit; and when the value of the TPM identifier is a second value, prohibiting the TPM from being used for processing a plurality of CUs in the preset video processing unit, wherein the first value is different from the second value.

In a possible implementation, the determining module 1002 is further configured to determine, according to the preset value of the TPM identifier, whether to allow processing of the plurality of CUs in the preset video processing unit using the TPM when the maximum number is less than the second threshold. .

In a possible implementation manner, the determining module 1002 is further configured to set the preset value of the TPM identifier to the second value when the code stream does not include the value information of the TPM identifier.

In a possible implementation manner, the determining module 1002 is further configured to determine that the code stream does not include TPM syntax information of the CU to be processed, where the TPM is used to construct a predicted value of the CU to be processed based on the TPM when the processing of the encoded CU using the TPM is prohibited.

It should be noted that, the parsing module 1001, the determining module 1002, and the optimizing module 1003 may be applied to an inter prediction process at the decoding end. Specifically, at the decoding end, these modules may be applied to the inter prediction unit 344 in the prediction processing unit 360 of the aforementioned decoder 30.

It should be further noted that, the specific implementation process of the parsing module 1001, the determining module 1002, and the optimizing module 1003 may refer to the detailed description of the embodiment of fig. 9, and for brevity of the description, the description is omitted here.

Based on the same inventive concept as the above method, the present application also provides an inter prediction apparatus, which may be applied to the above encoder 20.

Fig. 11 is another schematic structural diagram of an inter prediction apparatus in an embodiment of the present application, and referring to fig. 11, the inter prediction apparatus 1100 may include: an obtaining module 1101, configured to obtain a maximum number of candidate motion vector lists corresponding to a preset video processing unit; a determining module 1102, configured to determine whether to allow processing of a plurality of coding units CU in a preset video processing unit using a triangular prediction unit mode TPM according to a maximum number, where the plurality of CUs include CUs to be processed; and when the TPM is forbidden to process the plurality of coding units CU in the preset video processing unit, the TPM is forbidden to process the CU to be processed.

In a possible implementation manner, the determining module 1102 is further configured to determine, when the TPM is allowed to process the plurality of coding units CU in the preset video processing unit, whether to process the CU to be processed using the TPM according to the maximum number of candidate motion vector lists corresponding to the CU to be processed.

In a possible implementation manner, the determining module 1102 is specifically configured to compare the maximum number with a first threshold value, and determine whether to allow the TPM to process the plurality of coding units CU in the preset video processing unit; when the maximum number is larger than or equal to a first threshold value, the TPM is allowed to process a plurality of coding units CU in the preset video processing unit; when the maximum number is smaller than the first threshold, the TPM is prohibited from processing the plurality of coding units CU in the preset video processing unit.

In one possible implementation, the determining module 1102 is specifically configured to compare the maximum number with a second threshold; when the maximum number is smaller than the second threshold, it is determined whether to allow processing of the plurality of coding units CU in the preset video processing unit using the TPM according to the rate-distortion optimization.

In one possible implementation, referring to the dashed line in fig. 11, the apparatus 1100 further includes: an optimizing module 1103, configured to assign a TPM identifier corresponding to a preset video processing unit to a first value when processing is allowed to be performed on a plurality of coding units CU in the preset video processing unit using the TPM; when the TPM is prohibited from being used for processing the plurality of coding units CU in the preset video processing unit, the TPM identification is assigned to a second value, and the first value is different from the second value.

In one possible implementation, the optimizing module 1103 is configured to omit encoding of TPM syntax information of the CU to be processed when processing of the CU to be processed using the TPM is prohibited, where the TPM syntax information is used to construct a predicted value of the CU to be processed based on the TPM.

It should be noted that the obtaining module 1101, the determining module 1102 and the optimizing module 1103 may be applied to an inter prediction process at the encoding end. Specifically, at the encoding end, these modules may be applied to the inter prediction unit 244 in the prediction processing unit 260 of the encoder 20 described above.

It should be further noted that, the specific implementation processes of the obtaining module 1101, the determining module 1102 and the optimizing module 1103 may refer to the detailed description of the embodiment of fig. 9, and are not repeated herein for brevity of the description.

Those of skill in the art will appreciate that the functions described in connection with the various illustrative logical blocks, modules, and algorithm steps described in connection with the disclosure herein may be implemented as hardware, software, firmware, or any combination thereof. If implemented in software, the functions described by the various illustrative logical blocks, modules, and steps may be stored on a computer readable medium or transmitted as one or more instructions or code and executed by a hardware-based processing unit. Computer-readable media may include computer-readable storage media corresponding to tangible media, such as data storage media, or communication media including any medium that facilitates transfer of a computer program from one place to another (e.g., according to a communication protocol). In this manner, a computer-readable medium may generally correspond to (1) a non-transitory tangible computer-readable storage medium, or (2) a communication medium, such as a signal or carrier wave. Data storage media may be any available media that can be accessed by one or more computers or one or more processors to retrieve instructions, code and/or data structures for implementing the techniques described herein. The computer program product may include a computer-readable medium.

By way of example, and not limitation, such computer-readable storage media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer. Also, any connection is properly termed a computer-readable medium. For example, if the instructions are transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital Subscriber Line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. It should be understood, however, that the computer-readable storage medium and data storage medium do not include connections, carrier waves, signals, or other transitory media, but are actually directed to non-transitory tangible storage media. Disk and disc, as used herein, includes Compact Disc (CD), laser disc, optical disc, digital Versatile Disc (DVD), and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

The instructions may be executed by one or more processors, such as one or more Digital Signal Processors (DSPs), general purpose microprocessors, application Specific Integrated Circuits (ASICs), field programmable logic arrays (FPGAs), or other equivalent integrated or discrete logic circuitry. Thus, the term "processor" as used herein may refer to any of the foregoing structure or any other structure suitable for implementation of the techniques described herein. Additionally, in some aspects, the functions described by the various illustrative logical blocks, modules, and steps described herein may be provided within dedicated hardware and/or software modules configured for encoding and decoding, or incorporated in a combination codec. Moreover, the techniques may be fully implemented in one or more circuits or logic elements.

The techniques of this disclosure may be implemented in a wide variety of devices or apparatuses including a wireless handset, an Integrated Circuit (IC), or a set of ICs (e.g., a chipset). The various components, modules, or units are described in this application to emphasize functional aspects of the devices for performing the disclosed techniques but do not necessarily require realization by different hardware units. Indeed, as described above, the various units may be combined in a codec hardware unit in combination with suitable software and/or firmware, or provided by an interoperable hardware unit (including one or more processors as described above).

In the foregoing embodiments, the descriptions of the embodiments are emphasized, and for parts of one embodiment that are not described in detail, reference may be made to related descriptions of other embodiments.

The foregoing is merely illustrative of specific embodiments of the present application, and the scope of the present application is not limited thereto, and any changes or substitutions easily contemplated by those skilled in the art within the technical scope of the present application should be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A processing method based on a triangular prediction unit mode, comprising:

analyzing a code stream to obtain a first identifier, wherein the first identifier is used for determining whether a triangular prediction mode is allowed to be used in a preset video processing unit, and the preset video processing unit is a video sequence;

analyzing a fourth identifier from the sequence parameter set, wherein the fourth identifier is used for indicating the maximum capacity of a preset candidate prediction mode list of a decoding unit to be processed, and the preset candidate prediction mode list is a fusion mode candidate prediction mode list;

determining whether to allow processing of a plurality of coding units CU in the preset video processing unit by using a triangular prediction unit mode TPM according to the first identification, wherein the plurality of CUs comprise CUs to be processed;

When the maximum capacity is greater than or equal to a preset threshold, the prediction mode of the decoding unit to be processed is allowed to comprise a triangular prediction mode;

and when the TPM is forbidden to process the plurality of CUs in the preset video processing unit, the TPM is forbidden to process the CUs to be processed.

2. The method according to claim 1, wherein the prediction mode of the decoding unit to be processed is not allowed to include a triangular prediction mode when the maximum capacity is less than a preset threshold.

3. Method according to claim 1 or 2, characterized in that based on the maximum capacity, a prediction mode of the decoding unit to be processed is obtained.

4. The method according to any one of claims 1 to 2, wherein the preset threshold is 2.

5. The method according to any one of claims 1 to 2, wherein the TPM syntax information of the CU to be processed is decoded, the TPM syntax information being used to construct a predicted value obtained by the CU to be processed based on a TPM, wherein the TPM syntax information may include: for indicating whether the current CU uses the triangle prediction unit mode, for indicating a partition direction of the TPM, for indicating a first one of the fusion candidate index values in the TPM-based motion compensation candidate list, and for indicating a second one of the fusion candidate index values in the TPM-based motion compensation candidate list.

6. A processing method based on a triangular prediction unit mode, comprising:

obtaining the maximum number of candidate motion vector lists corresponding to a preset video processing unit;

determining whether to allow processing of a plurality of coding units CUs in the preset video processing unit by using a triangular prediction unit mode TPM according to the maximum number, wherein the plurality of CUs comprise CUs to be processed;

7. The method of claim 6, wherein the predetermined video processing unit is a video sequence.

8. The method according to claim 6 or 7, characterized in that the method further comprises:

when the TPM is allowed to process a plurality of CUs in the preset video processing unit, determining whether to process the CUs to be processed by using the TPM according to the maximum number of candidate motion vector lists corresponding to the CUs to be processed.

9. The method of claim 6 or 7, wherein the determining whether to allow processing of the plurality of CUs in the preset video processing unit using the TPM according to the maximum number comprises:

Comparing the maximum number with a first threshold;

when the maximum number is greater than or equal to the first threshold, allowing the TPM to process a plurality of CUs in the preset video processing unit;

and when the maximum number is smaller than the first threshold value, prohibiting the TPM from being used for processing the plurality of CUs in the preset video processing unit.

10. The method of claim 9, wherein the first threshold is 2.

11. The method according to any one of claims 6 to 7, further comprising:

when the TPM is allowed to process a plurality of CUs in the preset video processing unit, the TPM identifier corresponding to the preset video processing unit is assigned to be a first value.

12. The method of claim 11, wherein the TPM identification corresponding to the preset video processing unit is written into a bitstream.

13. The method of claim 8, wherein when processing the CU to be processed using a TPM is prohibited, the method further comprises:

omitting encoding of TPM grammar information of the CU to be processed, wherein the TPM grammar information is used for constructing a predicted value of the CU to be processed, the predicted value being obtained based on a TPM, and the TPM grammar information can comprise: for indicating whether the current CU uses the triangle prediction unit mode, for indicating a partition direction of the TPM, for indicating a first one of the fusion candidate index values in the TPM-based motion compensation candidate list, and for indicating a second one of the fusion candidate index values in the TPM-based motion compensation candidate list.

14. An inter prediction apparatus, comprising:

the analysis module is used for analyzing and obtaining a first identifier from the code stream, wherein the first identifier is used for determining whether the use of a triangular prediction mode is allowed in a preset video processing unit, and the preset video processing unit is a video sequence;

the determining module is used for determining whether to allow the processing of a plurality of coding units CU in a preset video processing unit by using a triangular prediction unit mode TPM according to the first identification, wherein the plurality of CUs comprise CUs to be processed;

15. The apparatus of claim 14, wherein the determining module is further configured to disallow the prediction mode of the decoding unit to be processed to include a triangular prediction mode when the maximum capacity is less than a preset threshold.

16. The apparatus according to any one of claims 14 or 15, wherein a prediction mode of the decoding unit to be processed is obtained based on the maximum capacity.

17. The apparatus according to any one of claims 14 or 15, wherein the preset threshold is 2.

18. The apparatus of claim 14, wherein the determining module is further configured to decode TPM syntax information of the CU to be processed, the TPM syntax information being used to construct a predicted value obtained by the CU to be processed based on a TPM, wherein the TPM syntax information may include: for indicating whether the current CU uses the triangle prediction unit mode, for indicating a partition direction of the TPM, for indicating a first one of the fusion candidate index values in the TPM-based motion compensation candidate list, and for indicating a second one of the fusion candidate index values in the TPM-based motion compensation candidate list.

19. An inter prediction apparatus, comprising:

the obtaining module is used for obtaining the maximum number of candidate motion vector lists corresponding to the preset video processing unit;

a determining module, configured to determine whether to allow processing of a plurality of coding units CU in the preset video processing unit using a triangular prediction unit mode TPM according to the maximum number, where the plurality of CUs include CUs to be processed; and when the TPM is forbidden to process the plurality of coding units CU in the preset video processing unit, the TPM is forbidden to process the CU to be processed.

20. The apparatus of claim 19, wherein the predetermined video processing unit is a video sequence.

21. The apparatus according to claim 19 or 20, wherein the determining module is further configured to determine, when processing is allowed for the plurality of coding units CU in the preset video processing unit using the TPM, whether to use the TPM to process the CU to be processed according to a maximum number of candidate motion vector lists corresponding to the CU to be processed.

22. The apparatus according to claim 19 or 20, wherein the determining module is configured to compare the maximum number with a first threshold value, and determine whether to allow processing of the plurality of coding units CU in the preset video processing unit using a TPM; when the maximum number is greater than or equal to the first threshold value, allowing the TPM to process a plurality of coding units CU in the preset video processing unit; and when the maximum number is smaller than the first threshold value, prohibiting the TPM from being used for processing the plurality of coding units CU in the preset video processing unit.

23. The apparatus of claim 22, wherein the first threshold is 2.

24. The apparatus according to any one of claims 19 to 20, further comprising: and the optimizing module is used for assigning the TPM identification corresponding to the preset video processing unit to a first value when the TPM is allowed to process the plurality of coding units CU in the preset video processing unit.

25. The apparatus of claim 24, wherein the apparatus further comprises: and writing the TPM identifier corresponding to the preset video processing unit into the code stream.

26. The apparatus of claim 19, wherein the apparatus further comprises: the optimizing module is configured to omit encoding of TPM syntax information of the CU to be processed when the CU to be processed is prohibited from being processed by using a TPM, where the TPM syntax information is used to construct a predicted value of the CU to be processed, which is obtained based on the TPM, where the TPM syntax information may include: for indicating whether the current CU uses the triangle prediction unit mode, for indicating a partition direction of the TPM, for indicating a first one of the fusion candidate index values in the TPM-based motion compensation candidate list, and for indicating a second one of the fusion candidate index values in the TPM-based motion compensation candidate list.

27. A video encoder for encoding image blocks, comprising:

the inter-prediction apparatus of any of claims 19 to 26, wherein the inter-prediction apparatus is configured to predict motion information of a current encoded image block based on target candidate motion information, and determine a predicted pixel value of the current encoded image block based on the motion information of the current encoded image block;

an entropy encoding module for encoding an index identification of the target candidate motion information into a bitstream, the index identification indicating the target candidate motion information for the current encoded image block;

a reconstruction module for reconstructing the current encoded image block based on the predicted pixel values.

28. A video decoder for decoding image blocks from a bitstream, comprising:

the entropy decoding module is used for decoding an index identifier from the code stream, wherein the index identifier is used for indicating target candidate motion information of the current decoded image block;

the inter-prediction apparatus according to any one of claims 14 to 18, the inter-prediction apparatus being configured to predict motion information of a current decoded image block based on target candidate motion information indicated by the index identification, determine a predicted pixel value of the current decoded image block based on the motion information of the current decoded image block;

A reconstruction module for reconstructing the current decoded image block based on the predicted pixel values.

29. A video codec device, comprising: a non-volatile memory and a processor coupled to each other, the processor invoking program code stored in the memory to perform the method as described in any of claims 1-13.