WO2023020560A1

WO2023020560A1 - Video coding and decoding method and apparatus, electronic device and storage medium

Info

Publication number: WO2023020560A1
Application number: PCT/CN2022/113182
Authority: WO
Inventors: 包佳晶
Original assignee: 百果园技术(新加坡)有限公司; 包佳晶
Priority date: 2021-08-20
Filing date: 2022-08-18
Publication date: 2023-02-23
Also published as: CN113613008A

Abstract

Disclosed in the present application are a video coding and decoding method and apparatus, an electronic device, and a storage medium. The coding method comprises: dividing a video frame comprising a luma component, a chroma component, and an Alpha component into a plurality of coding units (CUs), wherein the plurality of CUs comprise a luma coding block, a chroma coding block, and an Alpha coding block; and performing coding compression processing on the luma coding block, the chroma coding block, and the Alpha coding block respectively, and inputting the coding compression result and a related syntax element into a bitstream for transmission, the related syntax element comprising a syntax element corresponding to the Alpha coding block.

Description

Video encoding and decoding method, device, electronic equipment and storage medium

This application claims the priority of the Chinese patent application with application number 202110962461.7 submitted to the China Patent Office on August 20, 2021, the entire content of which is incorporated in this application by reference.

technical field

The embodiments of the present application relate to the technical field of video processing, for example, to a video encoding and decoding method, device, electronic equipment, and storage medium.

Background technique

The mainstream video compression standards deal with data in YUV format. The data in YUV format is encoded and then transmitted to the decoding end. After decoding by the decoding end, the data in YUV format is also obtained. Then the display device or post-processing part converts the YUV data Convert to RGB data for display and presentation.

There is no problem with the above-mentioned video transmission technology for ordinary video, but for video in RGBA (RGBA is a color space representing red (Red), green (Green), blue (Blue) and alpha (Alpha)) format, when using When the above video transmission technology is processed, the Alpha channel information will be lost, and only the RGB channel will be transcoded, compressed, and transcoded into YUV data. The lack of Alpha information makes it impossible to perform subsequent background removal, Alpha blending processing, and template processing.

Contents of the invention

The present application provides a video encoding and decoding method, device, electronic equipment, and storage medium to encode and decode videos containing Alpha data, save the transmission bandwidth of Alpha data, and improve the efficiency of encoding and decoding videos with Alpha data .

The embodiment of the present application provides a video coding method, including:

Divide a video frame comprising a luma component, a chrominance component, and an alpha Alpha component into a plurality of coding units CU, wherein the plurality of CUs include a luma encoding block, a chrominance encoding block, and an Alpha encoding block;

Perform encoding and compression processing on the luma encoding block, the chrominance encoding block, and the Alpha encoding block, and input the encoding and compression results and related syntax elements into a code stream for transmission, and the related syntax elements include the The syntax element corresponding to the Alpha code block.

The embodiment of the present application also provides a video decoding method, including:

Receiving a video code stream of a video frame to be decoded, the video code stream to be decoded includes a luma bit stream, a chrominance bit stream, an Alpha Alpha bit stream and related syntax elements;

According to the relevant syntax elements, the luminance bitstream, chrominance bitstream, and Alpha bitstream are respectively decoded to obtain reconstructed video frames comprising luminance data, chrominance data, and Alpha data.

The embodiment of the present application also provides a video encoding device, including:

A CU division module configured to divide a video frame comprising a luma component, a chrominance component, and an alpha Alpha component into a plurality of coding units CU, wherein the plurality of CUs include a luma encoding block, a chrominance encoding block, and an Alpha encoding block;

The CU encoding module is configured to perform encoding and compression processing on the luminance encoding block, the chrominance encoding block and the Alpha encoding block respectively, and input the encoding and compression results and related syntax elements into a code stream for transmission, and the related The syntax elements include syntax elements corresponding to the Alpha coding block.

The embodiment of the present application also provides a video decoding device, including:

The code stream receiving module is configured to receive the video code stream of the video frame to be decoded, the video code stream to be decoded includes a luma bit stream, a chrominance bit stream, an Alpha Alpha bit stream and related syntax elements;

The decoding module is configured to decode the luminance bit stream, chrominance bit stream, and Alpha bit stream respectively according to the relevant syntax elements, to obtain reconstructed video frames including luminance data, chrominance data, and Alpha data.

An embodiment of the present application also provides an electronic device, including a memory, a processor, and a computer program stored on the memory and operable on the processor, and the processor implements the method provided by any of the above-mentioned embodiments when executing the program .

The embodiment of the present application also provides a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the method provided in any of the above-mentioned embodiments is implemented.

Description of drawings

FIG. 1 is a flow chart of a video encoding method embodiment provided in Embodiment 1 of the present application;

FIG. 2 is a flowchart of a video decoding method embodiment provided in Embodiment 2 of the present application;

FIG. 3 is a structural block diagram of a video coding device embodiment provided in Embodiment 3 of the present application;

FIG. 4 is a structural block diagram of a video decoding device embodiment provided in Embodiment 4 of the present application;

FIG. 5 is a schematic structural diagram of an electronic device provided in Embodiment 5 of the present application.

Detailed ways

The application will be described below in conjunction with the accompanying drawings and embodiments. It should be understood that the embodiments described here are only used to explain the present application, but not to limit the present application. In addition, it should be noted that, for the convenience of description, only some structures related to the present application are shown in the drawings but not all structures.

Embodiment one

FIG. 1 is a flow chart of a video coding method embodiment provided in Embodiment 1 of the present application. This embodiment can be used in a scenario where a video stream containing alpha channel (Alpha channel) data is coded. Among them, the Alpha channel data is used to represent the additional information of the transparency of multiple pixels in a frame of image, and the transparency characteristics of the Alpha channel can be used to create rich image effects. For example: a bitmap that uses 16 bits per pixel to store, for each pixel in the picture, 5 bits may represent red (R), 5 bits may represent green (G), and 5 bits may represent blue Color (B), the last bit is Alpha. In this case, the alpha channel data is either transparent or opaque, because the value of the alpha bit has two different possibilities of representing 0 or 1. As another example, a bitmap stored with 32 bits per pixel, R, G, B, and Alpha are represented by 8 bits respectively. In this case, Alpha channel data can not only represent transparency and opacity, but also It can represent 256 levels of translucency, because the Alpha channel has 8 bits and can have 256 different data representation possibilities.

This embodiment can be applied to an encoder, as shown in Figure 1, this embodiment can include the following steps:

Step 110, divide the video frame comprising the luma component, the chrominance component and the Alpha Alpha component into a plurality of coding units (Coding Unit, CU), wherein the plurality of CUs include a luma coding block, a chrominance coding block and an Alpha Alpha code block.

In this embodiment, each coding block is a CU.

In this embodiment, the video frame to be encoded may include a luma component, a chroma component, and an Alpha component, and the encoder may be an encoder capable of encoding the luma component, the chroma component, and the Alpha component. In one embodiment, a video frame comprising a luminance component, a chrominance component and an Alpha component can be obtained in the following manner: RGB data and Alpha data in the video frame are extracted from a video frame in the RGBA image format to be encoded ; Converting the RGB data into YUV data; Embedding the Alpha data in the YUV data to generate a video frame comprising a brightness component, a chrominance component and an Alpha Alpha component.

The video stream to be encoded may be a video stream in RGBA format, and each video frame in the video stream is also an image in RGBA format. Among them, RGBA data is a color space representing red (Red), green (Green), blue (Blue) and transparency information (Alpha), and RGB is a color standard in the industry. G), the change of the three color channels of blue (B) and their mutual superposition to obtain different colors.

For a video frame in RGBA format, the pixel value in each pixel point is an RGBA value, that is, the pixel value of each pixel point includes an R component pixel value, a G component pixel value, a B component pixel value, and an Alpha component pixel value. By separating the RGBA pixel value of each pixel, the RGB pixel value and Alpha component pixel value of each pixel can be obtained.

Then for the RGB pixel value of each pixel, it can be converted into a YUV value, where the Y channel data represents the brightness, that is, the grayscale value; the U and V two channel data represent the chroma, which can be used to specify the color of the pixel .

In one embodiment, the following formula can be used to convert the RGB color data of each pixel into YUV data:

Y＝0.299R+0.587G+0.114B

U=-0.1687R-0.3313G+0.5B+128

V=0.5R-0.4187G-0.0813B+128

After obtaining the YUV data of each pixel, the Alpha channel data of each pixel can be combined with the YUV data of the pixel to finally generate a YUVA (YUV+Alpha) video frame.

For video frames in YUVA format, it can be divided into multiple CUs according to the set division mechanism. Wherein, there may be different segmentation mechanisms according to different video frame contents or encoding standards. For example, in High Efficiency Video Coding (HEVC) (also known as H.265 and MPEG-H Part 2), the video frame can first be divided into multiple coding tree units (Coding Tree Unit, CTU) , these coding tree units are blocks of a predefined size (eg, 64 pixels by 64 pixels). CTU includes brightness pixels, chroma pixels and Alpha pixels. An encoding tree can then be employed to divide each CTU into blocks and recursively subdivide these blocks until a configuration that supports further encoding is obtained. For example, the luma component of a frame can be subdivided until each luma block (i.e. luma coding block) includes a relatively uniform luma value; the chrominance component of a frame can also be subdivided until each chrominance block (i.e. Chroma encoding block) includes relatively uniform color values; the Alpha component of the frame can also be subdivided until each Alpha block (ie, Alpha encoding block) includes relatively uniform transparency values.

Step 120: Perform encoding and compression processing on the luminance encoding block, the chrominance encoding block, and the Alpha Alpha encoding block, and input the encoding and compression results and related syntax elements into the code stream for transmission, and the related syntax elements Include syntax elements corresponding to the Alpha coding block.

In this embodiment, based on the HEVC video coding technical standard in the related art, on the basis of luminance data and chrominance data, the Alpha channel data is introduced, and the entire encoding process adds the processing of the Alpha channel data, so that the While the Alpha channel data is compressed, the synchronous processing of the Alpha channel data, luminance data and chrominance data is guaranteed.

Based on the HEVC video coding standard in the related art, the coding and compression process may include the following processing stages: prediction processing, transform and quantization processing, entropy coding processing, inverse transform and quantization processing, filtering processing, reconstruction processing, and the like. The encoding and compression process may include the following process: first, the video encoder divides the input video image into non-overlapping coding units; then predictive coding is performed on the coding units, mainly using the spatial correlation and temporal correlation of the video, respectively using frame Intra-prediction and inter-frame prediction remove redundant information in space-time domain, so as to obtain the predicted image block; then the predicted image block is made difference with the original image block to obtain the prediction residual block, and then the discrete cosine transform (Discrete Cosine Transform, DCT) and quantization to obtain quantized DCT coefficients; finally, entropy coding is performed on the quantized DCT coefficients to obtain compressed code streams.

In this embodiment, after the Alpha channel data is added, in the prediction processing stage, multiple prediction units (Prediction Unit, PU) divided according to multiple CUs may include a luma prediction block (Prediction Block, PB), color Degree PB and AlphaPB, also includes related syntax elements. Then perform intra-frame prediction and inter-frame prediction on the luma PB, chroma PB, and Alpha PB respectively to determine the optimal prediction blocks corresponding to the luma PB, chroma PB, and Alpha PB respectively; finally calculate the luma PB and its corresponding optimal The residual signal between prediction blocks, the residual signal between chrominance PB and its corresponding optimal prediction block, and the residual signal between Alpha PB and its corresponding optimal prediction block are used as the processing results of prediction processing.

Exemplarily, multiple CUs are divided into multiple PUs, and multiple PUs include luma PB, chroma PB and Alpha PB, each luma encoding block may be divided into multiple luma PB, and each chrominance encoding block Divide into multiple chroma PBs, and divide each Alpha coding block into multiple Alpha PBs.

After dividing the PB, perform intra-frame prediction and inter-frame prediction on each luma PB, each chroma PB, and each Alpha PB to determine the optimal PB corresponding to each luma PB and the optimal PB corresponding to each chroma PB. Excellent PB and the optimal PB corresponding to each Alpha PB.

After determining the optimal PB, calculate the residual signal between each brightness PB and the optimal PB corresponding to each brightness PB, and the difference between each chroma PB and the optimal PB corresponding to each chroma PB and the residual signal between each Alpha PB and its corresponding optimal PB of each Alpha PB.

The process of the optimal prediction mode for each PB can be described as: Based on a mode selection criterion, traverse possible candidate modes, calculate the encoding cost of each candidate mode under the current criterion, and select the candidate mode with the smallest encoding cost as Optimal forecasting model.

After the prediction process, the residual signal of the prediction block is obtained. In order to compress the statistical redundancy of the residual signal, the residual signal needs to be transformed and quantized. In the transform processing stage, the residual signal corresponding to the luma prediction block, the residual signal corresponding to the chroma prediction block and the residual signal corresponding to the Alpha prediction block are divided into multiple transform units TU, and the multiple PUs may include luma transform blocks ( Transform Block, TB), chroma transform block TB and Alpha transform block TB, and also includes related syntax elements. Then DCT transform processing and quantization processing are performed on the luma TB, chroma TB, and Alpha TB respectively to obtain the quantization parameters corresponding to the luma transform block, the quantization parameters corresponding to the chroma transform block, and the quantization parameters corresponding to the Alpha transform block.

Exemplarily, after calculating the residual signal between each luminance PB and the optimal PB corresponding to each luminance PB, each chroma PB and the optimal PB corresponding to each chroma PB, After the residual signal between each Alpha PB and the optimal PB corresponding to each Alpha PB, the multiple residual signals calculated according to multiple brightness PBs are transformed into multiple brightness TBs , converting multiple residual signals calculated according to multiple chroma PBs into multiple chrominance TBs, and transforming multiple residual signals calculated according to multiple Alpha PBs into multiple Alpha TBs.

After the TB is obtained, discrete cosine transform processing and quantization processing are performed on each luma TB, each chroma TB, and each Alpha TB, respectively, to obtain quantization parameters corresponding to each luma TB, quantization parameters corresponding to each chroma TB, and Quantization parameters corresponding to each Alpha TB.

Wherein, the process of transformation processing and quantization processing can be as follows: DCT transformation is performed on TB to obtain direct current (Direct Current, DC) coefficients and alternating current (Alternating Current, AC) coefficients, and then the DC coefficients are subjected to Hadamard product (Hadamard) transformation, The transformed DC and AC coefficients are then quantized. Quantization reduces the bit rate through many-to-one mapping. There are mainly uniform quantization, non-uniform quantization and adaptive quantization. According to the optimal quantizer design criterion: the boundary value of the optimal quantization interval is the average of two adjacent optimal quantization values, and the optimal quantization value is the mean value of the quantization interval.

In the entropy encoding processing stage, entropy encoding is performed on the quantization parameters corresponding to luma TB, quantization parameters corresponding to chroma TB, and quantization parameters corresponding to Alpha TB, so that the result of entropy encoding is output in the form of bit stream. In this embodiment, descriptive sentences for Alpha data are also added to the entropy coding syntax generated in the entropy coding stage, so as to ensure that the decoding end can correctly decode and restore the alpha data.

In an example, the entropy coding syntax may include: a sequence parameter set (Sequence Paramater Set, sps) including an Alpha component, as shown in the following table:

"enable_alpha_flag" is the new sps about Alpha data.

In another example, the entropy encoding syntax may further include: a residual entropy syntax including an Alpha component, and the newly added residual entropy syntax of the Alpha component is shown in the following table:

In the above table, the "..." part is the entropy coding syntax in the related art, and the entropy coding syntax may include description information for chrominance data and luminance data.

In this embodiment, when encoding and compressing the CU, the Alpha data and the YUV data are encoded and compressed synchronously. The bandwidth occupation of Alpha data, thereby improving the compression efficiency of the video.

Embodiment two

FIG. 2 is a flowchart of a video decoding method embodiment provided in Embodiment 2 of the present application. This embodiment can be used in a scenario where a video code stream containing alpha data is decoded. May include the following steps:

Step 210, receiving a video code stream of a video frame to be decoded, the video code stream to be decoded includes a luma bit stream, a chrominance bit stream, an Alpha bit stream and related syntax elements.

Step 220: Decode the luminance bit stream, chrominance bit stream, and Alpha bit stream respectively according to the relevant syntax elements to obtain reconstructed video frames including luminance data, chrominance data, and Alpha data.

The video decoding process is exactly the opposite of the encoding process. When decoding, the code stream is first entropy decoded to obtain the quantized coefficients after scanning, and then through inverse scanning, inverse quantization and inverse transformation to obtain the decoded residual coefficients, and then A decoded reconstructed image is obtained through motion compensation, and the reconstructed image includes luminance data, chrominance data and Alpha data.

After the decoder outputs video frames containing luminance data, chrominance data and Alpha data, the display device or post-processing part can convert the luminance data and chrominance data into RGB data, and then combine the RGB data and Alpha data into RGBA data display for users to use.

In this embodiment, by decoding the video code stream including luminance bit stream, chrominance bit stream, Alpha bit stream and related syntax elements, the Alpha data in the code stream can be obtained, which is convenient for subsequent background removal and Alpha mixing. processing and template processing etc.

Embodiment three

Fig. 3 is a structural block diagram of a video encoding device embodiment provided in Embodiment 3 of the present application, which may include the following modules: CU division module 310, configured to divide video frames containing luminance components, chrominance components, and alpha Alpha components into a plurality of coding units CU, wherein the plurality of CUs include a luma coding block, a chrominance coding block, and an Alpha Alpha coding block; Perform encoding and compression processing with the Alpha encoding block, and input the encoding and compression result and related syntax elements into a code stream for transmission, and the related syntax elements include syntax elements corresponding to the Alpha encoding block.

In an embodiment, the encoding and compression processing includes prediction processing, and the CU encoding module 320 may include the following submodules: a prediction processing submodule configured to divide the multiple CUs into multiple prediction units PU, so that The plurality of PUs include a luma prediction block, a chroma prediction block, and an Alpha prediction block; intra-frame prediction and inter-frame prediction are respectively performed on the luma prediction block, the chroma prediction block, and the Alpha prediction block to determine the The optimal prediction block corresponding to the luminance prediction block, the optimal prediction block corresponding to the chroma prediction block, and the optimal prediction block corresponding to the Alpha prediction block; The residual signal between the optimal prediction block, the residual signal between the chroma prediction block and the optimal prediction block corresponding to the chroma prediction block, and the Alpha prediction block corresponding to the Alpha prediction block The residual signal between optimally predicted blocks of .

In one embodiment, the encoding and compression processing further includes transform and quantization processing; the CU encoding module 320 may include the following submodules: a transform and quantization submodule, configured to convert the residual signal corresponding to the luma prediction block, the chroma prediction The residual signal corresponding to the block and the residual signal corresponding to the Alpha prediction block are divided into a plurality of transformation units TU, and the plurality of TUs include a luma transformation block, a chrominance transformation block, and an Alpha transformation block; The chroma transform block and the Alpha transform block perform DCT transform processing and quantization processing to obtain quantization parameters corresponding to the luma transform block, quantization parameters corresponding to the chroma transform block, and quantization parameters corresponding to the Alpha transform block.

In one embodiment, the encoding and compression processing further includes entropy encoding processing; the CU encoding module 320 may include the following submodules: an entropy encoding submodule, configured to perform quantization parameters corresponding to the luma transformation block, chrominance The quantization parameters corresponding to the transform block and the quantization parameters corresponding to the Alpha transform block are entropy encoded, and the entropy encoded result is output in the form of a bit stream.

In an embodiment, the relevant syntax elements include entropy coding syntax generated in the entropy coding stage; the entropy coding syntax includes: a sequence parameter including an Alpha component, and a residual entropy syntax including an Alpha component.

In one embodiment, the device also includes a video frame acquisition module, configured to extract the RGB data and Alpha data in the video frame from the video frame of the RGBA image format to be encoded; convert the RGB data into YUV data; embedding the Alpha data in the YUV data to generate a video frame comprising a brightness component, a chrominance component and an Alpha Alpha component.

It should be noted that the above-mentioned video coding device provided in the embodiment of the present application can execute the video coding method provided in the first embodiment of the present application, and has corresponding functional modules and effects for executing the method.

Embodiment four

FIG. 4 is a structural block diagram of a video decoding device embodiment provided in Embodiment 4 of the present application, which may include the following modules: a code stream receiving module 410, configured to receive a video code stream of a video frame to be decoded, and the video code stream to be decoded The code stream includes a luminance bit stream, a chrominance bit stream, an Alpha Alpha bit stream, and related syntax elements; the decoding module 420 is configured to, respectively, perform operations on the luminance bit stream, the chrominance bit stream, and the Alpha bit stream according to the related syntax elements. The stream is decoded to obtain a reconstructed video frame including luminance data, chrominance data, and Alpha data.

It should be noted that the above-mentioned video decoding device provided in the embodiment of the present application can execute the video decoding method provided in the second embodiment of the present application, and has corresponding functional modules and effects for executing the method.

Embodiment five

FIG. 5 is a schematic structural diagram of an electronic device provided in Embodiment 5 of the present application. As shown in FIG. 5 , the electronic device includes a processor 510, a memory 520, an input device 530, and an output device 540; The quantity can be one or more, and a processor 510 is taken as an example in FIG. Take the bus connection as an example.

The memory 520, as a computer-readable storage medium, can be configured to store software programs, computer-executable programs and modules, such as program instructions/modules corresponding to the methods in the embodiments of the present application. The processor 510 executes various functional applications and data processing of the electronic device by running software programs, instructions and modules stored in the memory 520 , that is, implements the above-mentioned method.

The memory 520 may mainly include a program storage area and a data storage area, wherein the program storage area may store an operating system and an application program required by at least one function; the data storage area may store data created according to the use of the terminal, and the like. In addition, the memory 520 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other non-volatile solid-state storage devices. In some examples, memory 520 may include memory located remotely from processor 510, and such remote memory may be connected to the electronic device through a network. Examples of the aforementioned networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

The input device 530 can be configured to receive input numbers or character information, and generate key signal input related to user settings and function control of the electronic device. The output device 540 may include a display device such as a display screen.

Embodiment six

Embodiment 6 of the present application further provides a storage medium containing computer-executable instructions, and the computer-executable instructions are used to execute the method in any embodiment of the present application when executed by a processor of the server.

Through the above description about the implementation manners, those skilled in the art can clearly understand that the present application can be implemented by means of software and general hardware, and of course can also be implemented by means of hardware. Based on this understanding, the technical solution of the present application can be embodied in the form of software products, and the computer software products can be stored in computer-readable storage media, such as computer floppy disks, read-only memory (Read-Only Memory, ROM), Random access memory (Random Access Memory, RAM), flash memory (FLASH), hard disk or optical disc, etc., including at least one instruction to make a computer device (which can be a personal computer, server, or network device, etc.) execute multiple The method described in an example.

In the embodiment of the above-mentioned device, the multiple units and modules included are only divided according to the functional logic, but are not limited to the above-mentioned division, as long as the corresponding functions can be realized; in addition, the specific names of the multiple functional units It is only for the convenience of distinguishing each other, and is not used to limit the protection scope of the present application.

Claims

A method of video encoding, comprising:

Divide a video frame comprising a luma component, a chrominance component, and an alpha Alpha component into a plurality of coding units CU, wherein the plurality of CUs include a luma encoding block, a chrominance encoding block, and an Alpha encoding block;

Perform encoding and compression processing on the luma encoding block, the chrominance encoding block, and the Alpha encoding block, and input the encoding and compression results and related syntax elements into a code stream for transmission, and the related syntax elements include the The syntax element corresponding to the Alpha code block.
The method according to claim 1, wherein the encoding and compression processing includes prediction processing, and performing encoding and compression processing on the brightness encoding block, the chrominance encoding block and the Alpha encoding block respectively includes:

dividing the plurality of CUs into a plurality of prediction units PU, the plurality of PUs including a luma prediction block, a chroma prediction block, and an Alpha prediction block;

Intra-frame prediction and inter-frame prediction are respectively performed on the luma prediction block, the chroma prediction block, and the Alpha prediction block, so as to determine the optimal prediction block corresponding to the luma prediction block and the corresponding optimal prediction block of the chroma prediction block. The optimal prediction block of and the optimal prediction block corresponding to the Alpha prediction block;

respectively calculating the residual signal between the luma prediction block and the optimal prediction block corresponding to the luma prediction block, and the residual error between the chroma prediction block and the optimal prediction block corresponding to the chroma prediction block signal and a residual signal between the Alpha prediction block and the optimal prediction block corresponding to the Alpha prediction block.
The method according to claim 2, wherein said encoding and compression processing further comprises transform and quantization processing;

respectively calculating the residual signal between the luma prediction block and the optimal prediction block corresponding to the luma prediction block, the residual signal between the chroma prediction block and the optimal prediction block corresponding to the chroma prediction block After the difference signal and the residual signal between the Alpha prediction block and the optimal prediction block corresponding to the Alpha prediction block, it also includes:

Divide the residual signal corresponding to the luma prediction block, the residual signal corresponding to the chroma prediction block and the residual signal corresponding to the Alpha prediction block into a plurality of transform units TU, the plurality of TUs including luma transform block, chroma transform block, and alpha transform block;

Perform discrete cosine transform processing and quantization processing on the luma transform block, chroma transform block, and Alpha transform block, respectively, to obtain quantization parameters corresponding to the luma transform block, quantization parameters corresponding to the chroma transform block, and alpha transform block corresponding quantization parameters.
The method according to claim 3, wherein the encoding compression process further comprises an entropy encoding process;

After obtaining the quantization parameter corresponding to the luma transformation block, the quantization parameter corresponding to the chroma transformation block, and the quantization parameter corresponding to the Alpha transformation block, it further includes: the quantization parameter corresponding to the luma transformation block, the chroma transformation block Entropy encoding is performed on the corresponding quantization parameters and the quantization parameters corresponding to the Alpha transformation block, and the entropy encoding result is output in the form of a bit stream.
The method according to claim 4, wherein the relevant syntax elements include entropy coding syntax generated in the entropy coding stage; the entropy coding syntax includes: sequence parameters including Alpha components, and residual entropy syntax including Alpha components.
The method according to any one of claims 1-5, wherein the video frame comprising a luminance component, a chrominance component and an Alpha component is obtained in the following manner:

Extract RGB data and Alpha data in the video frame from the video frame of the RGBA image format to be encoded;

Converting the RGB data into YUV data;

Embedding the Alpha data into the YUV data to generate a video frame including a brightness component, a chrominance component, and an Alpha component.
A method for video decoding, comprising:

Receiving a video code stream of a video frame to be decoded, the video code stream to be decoded includes a luma bit stream, a chrominance bit stream, an Alpha Alpha bit stream and related syntax elements;

Decode the luminance bit stream, chrominance bit stream, and Alpha bit stream respectively according to the relevant syntax elements to obtain reconstructed video frames including luminance data, chrominance data, and Alpha data.
A device for video encoding, comprising:

A CU division module configured to divide a video frame comprising a luma component, a chrominance component, and an alpha Alpha component into a plurality of coding units CU, wherein the plurality of CUs include a luma encoding block, a chrominance encoding block, and an Alpha encoding block;

The CU encoding module is configured to perform encoding and compression processing on the luminance encoding block, the chrominance encoding block and the Alpha encoding block respectively, and input the encoding and compression results and related syntax elements into a code stream for transmission, and the related The syntax elements include syntax elements corresponding to the Alpha coding block.
A video decoding device, the device comprising:

The code stream receiving module is configured to receive the video code stream of the video frame to be decoded, the video code stream to be decoded includes a luma bit stream, a chrominance bit stream, an Alpha Alpha bit stream and related syntax elements;

The decoding module is configured to decode the luminance bit stream, chrominance bit stream, and Alpha bit stream respectively according to the relevant syntax elements, to obtain reconstructed video frames including luminance data, chrominance data, and Alpha data.
An electronic device, comprising a memory, a processor, and a computer program stored in the memory and operable on the processor, when the processor executes the program, the method according to any one of claims 1-7 is implemented.
A computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the method according to any one of claims 1-7 is implemented.