Image prediction method, encoder, decoder, and storage medium

Abstract

To provide a picture prediction method, encoder, decoder and storage medium that use a Matrix-based Intra Prediction (MIP) mode.SOLUTION: An encoder sets a value of an MIP mode parameter as indicating the use of the MIP mode and writes it into a bitstream; determines the MIP mode of a current block; determines, based on the MIP mode, prediction values for luma and chroma components corresponding to the current block; and writes the MIP mode of the current block into the bitstream. The decoder parses the bitstream and determines an MIP mode parameter of the current block; if the MIP mode parameter value indicates that the current block uses the MIP mode to determine an intra prediction value of the current block, parses the bitstream, determines the MIP mode of the current block and prediction values of luma and chroma components corresponding to the current block based on the MIP mode; and decodes the current block based on the prediction values.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] [Cross - Reference to Related Applications] This application is filed based on and claims the priority of a U.S. Provisional Patent Application with Application No. 62 / 871,177, filed on July 7, 2019, and the title of the invention being "Method, Apparatus, and System for Encoding and Decoding Video Data". Herein, all the contents of the U.S. Provisional Patent Application are incorporated herein by reference. Embodiments of this application relate to the field of video encoding / decoding technology, particularly to image prediction methods, encoders, decoders, and storage media.

Background Art

[0002] In the reference software test platform of Versatile Video Coding (VVC), a new intra - coding technology, namely Matrix - based Intra Prediction (MIP), has been proposed. MIP is an intra - prediction technology based on neural networks, that is, it uses a multi - layer neural network to predict the luminance value of the current block based on adjacent reconstructed luminance blocks. Specifically, similar to the conventional intra - mode, when performing intra - prediction using the MIP mode, the input predicted by MIP is also the data of the adjacent luminance blocks in the upper 1 row and the left 1 column of the current block, and the output is the predicted value of the luminance component of the current block. The specific prediction process can be divided into three steps: downsampling, matrix - vector multiplication, and interpolation.

[0003] However, due to the higher complexity of the MIP mode, the MIP technology improves the encoding / decoding performance while also significantly increasing the storage space and overall time required for the encoding / decoding process, thereby reducing the encoding / decoding efficiency.

Summary of the Invention

Problems to be Solved by the Invention

[0004] The embodiments of this application provide an image prediction method, an encoder, a decoder, and a storage medium, which can reduce complexity, decrease the memory space and overall time required for the encoding / decoding process, and effectively improve encoding / decoding efficiency in ensuring encoding / decoding performance. [Means for solving the problem]

[0005] The technical solution of the embodiment of this application is realized as follows.

[0006] In a first aspect, an embodiment of the present application provides an image prediction method, which is applied to an encoder, and the method is If the current block uses MIP mode to determine the intra-predicted value of the current block, the value of the MIP mode parameter is set to indicate the use of MIP mode and written to the bitstream. The MIP mode of the current block is determined, and based on the MIP mode, the predicted values ​​of the luminance component and chromaticity component corresponding to the current block are determined. This includes writing the MIP mode of the current block to the bitstream.

[0007] In a second aspect, an embodiment of the present application provides an image prediction method, which is applied to a decoder, and the method is Analyze the bitstream to determine the MIP mode parameters of the current block, If the value of the MIP mode parameter indicates that the current block uses the MIP mode to determine the intra-predicted value of the current block, the bitstream is analyzed to determine the MIP mode of the current block, and the predicted values ​​of the luminance component and chromaticity component corresponding to the current block are determined based on the MIP mode. This includes decoding the current block based on the predicted value.

[0008] In a third aspect, an embodiment of the present application provides an encoder comprising a setting unit, a first determination unit, and an encoding unit. The setting unit is configured to write the value of the MIP mode parameter to the bitstream, indicating that the MIP mode should be used, when the current block uses MIP mode to determine the intra-predicted value of the current block. The first determination unit is configured to determine the MIP mode of the current block and to determine predicted values ​​of the luminance component and chromaticity component corresponding to the current block based on the MIP mode. The encoding unit is configured to write the MIP mode of the current block to the bitstream.

[0009] In a fourth aspect, an embodiment of the present application provides an encoder comprising a first processor and a first memory storing instructions that can be executed by the first processor, and when the instructions are executed by the first processor, the image prediction method described above is realized.

[0010] In a fifth aspect, an embodiment of the present application provides a decoder comprising a decoding unit and a second determination unit, The decoding unit is configured to analyze the bitstream to determine the MIP mode parameter of the current block, and to analyze the bitstream to determine the MIP mode of the current block if the value of the MIP mode parameter indicates that the current block uses the MIP mode to determine the intra-predicted value of the current block. The second determination unit is configured to determine predicted values ​​of the luminance component and chromaticity component corresponding to the current block based on the MIP mode, The decoding unit is further configured to decode the current block based on the predicted value.

[0011] In the sixth aspect, an embodiment of the present application provides a decoder comprising a second processor and a second memory storing instructions that can be executed by the second processor, and when the instructions are executed by the second processor, the image prediction method described above is realized.

[0012] In the seventh aspect, an embodiment of the present application provides a computer-readable storage medium on which a program is stored and applied to an encoder and decoder, and when the computer program is executed by a first processor, the image prediction method described above is realized, or when it is executed by a second processor, the image prediction method described above is realized. [Effects of the Invention]

[0013] Embodiments of the present invention provide an image prediction method, an encoder, a decoder, and a storage medium. When the current block uses MIP mode to determine its intra-predicted value, the encoder writes the value of the MIP mode parameter to the bitstream, indicating the use of MIP mode, determines the MIP mode of the current block, determines the predicted values ​​of the luminance and chromaticity components corresponding to the current block based on the MIP mode, and writes the MIP mode of the current block to the bitstream. The decoder analyzes the bitstream to determine the MIP mode parameter of the current block. When the value of the MIP mode parameter indicates that the current block uses MIP mode to determine its intra-predicted value, the decoder analyzes the bitstream to determine the MIP mode of the current block, determines the predicted values ​​of the luminance and chromaticity components corresponding to the current block based on the MIP mode, and decodes the current block based on the predicted values. In other words, in the embodiment of the present invention, when the encoder performs intraprediction on the current block, if it decides that the current block will use MIP mode, it can obtain the intrapredicted value of the current block using MIP mode, set the MIP mode parameters, write them to the bitstream, and transmit them to the decoding side. The decoder analyzes the bitstream to obtain the MIP mode parameters, and if the MIP mode parameters indicate that the current block will use MIP mode, the decoder can determine the intrapredicted value of the current block using MIP mode. As can be seen from the above, the image prediction method according to the present invention can use a grammar unit to indicate in the bitstream whether the current block will use MIP mode, thereby simplifying the image prediction process, reducing complexity in ensuring encoding / decoding performance, decreasing the memory space and overall time required for the encoding / decoding process, and effectively improving encoding / decoding efficiency. [Brief explanation of the drawing]

[0014] [Figure 1] Figure 1 is a schematic diagram illustrating the distribution of 67 prediction modes in intra-prediction. [Figure 2] FIG. 2 is a schematic flowchart for encoding in the MIP mode. [Figure 3] FIG. 3 is a schematic distribution diagram of the upper adjacent luminance block and the left adjacent luminance block of the current block. [Figure 4] FIG. 4 is a schematic distribution diagram for determining the DM mode. [Figure 5] FIG. 5 is a schematic structural diagram of a video encoding system. [Figure 6] FIG. 6 is a schematic structural diagram of a video decoding system. [Figure 7] FIG. 7 is a schematic implementation flowchart 1 of an image prediction method. [Figure 8] FIG. 8 is a schematic implementation flowchart 2 of an image prediction method. [Figure 9] FIG. 9 is a schematic structural diagram 1 of an encoder according to an embodiment of the present application. [Figure 10] FIG. 10 is a schematic structural diagram 2 of an encoder according to an embodiment of the present application. [Figure 11] FIG. 11 is a schematic structural diagram 1 of a decoder according to an embodiment of the present application. [Figure 12] FIG. 12 is a schematic structural diagram 2 of a decoder according to an embodiment of the present application.

DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, the technical solutions of the embodiments of the present application will be clearly and completely described with reference to the drawings of the embodiments of the present application. As can be understood, the specific embodiments described here are only for interpreting the related application and do not limit the application. Also, as further described, for the convenience of explanation, only the parts related to the related application are shown in the drawings.

[0016] Currently, the Recommendations on Communications (ITU-T) and the International Organization for Standardization (ISO) / International Electrotechnical Commission (IEC) have launched a standardization project called General-Purpose Video Coding (VVC) to develop a new generation video coding standard. Its purpose is to improve VVC performance by approximately 50% compared to the latest H.265 / HEVC standard when coding high-quality video with one or more features among high resolution, high frame rate, high bit depth, high dynamic range, wide color gamut, and omnidirectional viewing angle. JVET is responsible for this standardization project and has verified that it can achieve high compression efficiency when coding high-quality video in various intra-predictive and inter-predictive modes, and therefore will be adopted in the VVC working draft.

[0017] In video images, VVC accepts the Affine Linear Weighted Intra Prediction technique proposed by the Joint Video Experts Team (JVET)-N0217, renaming it Matrix-Based Intra Prediction, or MIP, which adds a different number of matrix-based intra prediction modes to the intra luminance prediction process depending on differences in intra luminance coding block sizes.

[0018] To capture finer edge directions in natural video, the 33 intra-luminance prediction angle modes defined in the video compression standard (HEVC, High Efficiency Video Coding) in VVC are expanded to 65. Figure 1 is a schematic diagram of the distribution of the 67 prediction modes in intra-prediction. As shown in Figure 1, arrows 2 to 66 indicate the 65 intra-angle prediction modes. In addition, there are two non-angle modes, namely the stepped planar mode (number 0) and the DC mode (number 1). Therefore, the intra-prediction process in VVC includes two non-angle modes and 65 angle modes, and these 67 prediction modes are referred to as the conventional modes of intra-prediction.

[0019] MIP is an intra-prediction technique based on neural networks, specifically, it uses a multi-layer neural network to predict the luminance value of the current block based on adjacent reconstructed pixels. Specifically, the MIP technique divides luminance coding blocks into three types based on their size, setting the size of the luminance coding block as W × H, where W is the width parameter and H is the height parameter. Based on the size of the luminance coding block, the luminance coding block can be divided into three types. A luminance coding block of size 4x4 is designated as the first type of luminance block, luminance coding blocks of sizes 8x4, 4x8, and 8x8 are designated as the second type of luminance block, and luminance coding blocks of other sizes are designated as the third type of luminance block.

[0020] For these three types of intra-luminance coding blocks, MIP technology adds M MIP modes to the 67 conventional intra-prediction modes, with M=16 for the first type of luminance block, M=8 for the second type of luminance block, and M=6 for the third type of luminance block.

[0021] Specifically, the MIP technology is applied only to intra-luminance prediction. Similar to the conventional mode, the input for MIP prediction is the data from the top row and left column of the current block, and the output is the predicted value of the current block. The prediction process is divided into three steps: averaging, matrix-vector multiplication, and interpolation. That is, by performing these three steps on the reconstructed luminance values ​​of adjacent pixel points in the top row and left column of the input, the predicted value of the luminance component of the current block can be obtained.

[0022] Figure 2 is a schematic flowchart of the encoding process in MIP mode. As shown in Figure 2, brightness prediction in MIP mode is specifically implemented as follows.

[0023] In the first step, an averaging operation is performed on the upper adjacent reference points of the current block to create the vector bdry. topWe obtain the values, sum them up to get N values, and perform an average operation on the left neighbor reference point of the current block to create the vector bdry left The values ​​are obtained and totaled to obtain N values. If the current brightness number is of type 1, then N=2, and if the current brightness number is of type 2 or type 3, then N=4. Vector bdry top and vector bdry left This creates a new vector bdry red The configuration is then performed to carry out subsequent operations.

[0024] In the second step, the corresponding matrix A is determined by the mode number k of the MIP mode. k and offset amount b k The following formula (1) is used to calculate and obtain predicted values ​​for a portion of the current block, indicated by the crossing lines in Figure 2.

number

[0025] In the third step, the remaining predicted value Predred in the current block is obtained by linear interpolation.

[0026] Currently, the implementation process for encoding blocks requires that the intra-prediction writes the specific encoding mode to be used into the compressed bitstream. This allows the decoding side to analyze the mode information and determine which mode to use, whether it is a conventional mode or an MIP mode, and if it is a conventional mode, which specific conventional mode, or if it is an MIP mode, which specific MIP mode.

[0027] In VVC intra-prediction, the rate distortion cost (RDcost) of 67 conventional modes and M MIP modes is compared for each luminance coding block, and the optimal mode is selected from the 67 conventional modes and M MIP modes for coding. To save bit overhead, VVC uses intra-mode coding techniques based on the Most Probable Modes List (MPM). Furthermore, since the extended reference line technique and the intra sub-partitioning technique (ISP) are used only for the mode in the MPM list, if both extendrefflag and ispflag are 0, that is, if a 0 reference line is used and sub-partitioning is not performed, there is no need to encode mpmflag, and the position in the MPM list for the optimal mode is encoded directly.

[0028] Furthermore, regarding the construction of the MPM list and MIPMPM list, in VVC luminance intra prediction, if the currently selected optimal mode for a block is the conventional mode, it is necessary to construct an MPM list containing six most probable conventional modes. If the currently selected optimal mode for a block is the MIP mode, it is necessary to construct an MIPMPM list containing three most probable MIP modes.

[0029] Figure 3 is a schematic diagram of the distribution of the luminance blocks adjacent to the upper and left sides of the current block. As shown in Figure 3, both of the above lists are derived based on the optimal modes of the luminance blocks adjacent to the upper (A) and left (L) sides of the current block shown in Figure 3.

[0030] Specifically, regarding the construction of the MPM list, in VVC intra prediction, if the current block's optimal mode is the conventional mode, it is necessary to construct the MPM list. In the process of constructing the MPM list, it is first necessary to obtain the conventional mode ABOVE corresponding to the optimal mode of the upper adjacent luminance block and the conventional mode LEFT corresponding to the optimal mode of the left adjacent luminance block.

[0031] Furthermore, regarding the construction of the MIPMPM list, in VVC intra prediction, if the current optimal mode for a block is MIP mode, it is necessary to construct the MIPMPM list. In the process of constructing the MIPMPM list, it is first necessary to obtain the MIP mode ABOVE_MIP corresponding to the optimal mode of the upper adjacent luminance block and the MIP mode LEFT_MIP corresponding to the optimal mode of the left adjacent luminance block.

[0032] Furthermore, after obtaining LEFT_MIP and ABOVE_MIP, a MIPMPM list containing three most probable MIPMPM modes is constructed based on the following method, where the numbers in MIPMPM are MIP mode numbers, the number range is 0 to (M-1), the first type of luminance block number is 0 to 15, the second type of luminance block number is 0 to 7, and the third type of luminance block number is 0 to 5. If LEFT_MIP is available (not -1), put LEFT_MIP into MIPMPMlist, If ABOVE_MIP is available (not -1), then ABOVE_MIP will pass the redundancy check and be added to MIPMPMlist. If LEFT_MIP is unavailable (-1) and ABOVE_MIP is unavailable (-1), the default list is added based on the current block type, passing redundancy checks, until MIPMPMlist is full. Furthermore, in the VVC chromaticity intra-prediction process, there is a direct mode (DM) that utilizes the relationships between components. This direct mode uses the intra-prediction mode of the center position of the luminance coding block at the same position corresponding to the current block to perform intra-prediction of the current chromaticity block. Figure 4 is a schematic distribution diagram that determines the DM mode. As shown in Figure 4, since the MIP technology is applied only to luminance coding blocks, if the intra-prediction mode of the CR position in Figure 4 is the MIP mode, it is necessary to map the MIP mode to the conventional mode using the "MIP-conventional mapping table" to perform intra-prediction of the current chromaticity block.

[0033] Due to the computational load and memory costs required for MIP technology, it is difficult to implement MIP mode on devices with lower computing or memory capabilities. Consequently, it is impossible to effectively transmit and control MIP mode in the latest VVC working draft designs, and therefore it is difficult to implement in flexible encoding / decoding and dynamic video streams.

[0034] To address the above-mentioned shortcomings, in the embodiments of the present invention, when the encoder performs intra-prediction on the current block, if it decides that the current block should use MIP mode, it can obtain the intra-predicted value of the current block using MIP mode, set the MIP mode parameters, write them to the bitstream, and transmit them to the decoder. The decoder can analyze the bitstream to obtain the MIP mode parameters, and if the MIP mode parameters indicate that the current block should use MIP mode, the decoder can determine the intra-predicted value of the current block using MIP mode. That is, in the present invention, the VVC bitstream transmits one or more grammar elements to enable or disable MIP mode. The grammar elements may be located in the video sequence layer, picture layer and / or sub-picture layer, or in data units in the slice / tile / brick layer, where a sub-picture refers to an area covering a portion of a picture. As can be seen from the above, the image prediction method according to the present invention can use a grammar unit to indicate whether the current block in the bitstream uses MIP mode, thereby simplifying the image prediction process for MIP mode, reducing complexity in ensuring encoding / decoding performance, decreasing the memory space and overall time required for the encoding / decoding process, and effectively improving encoding / decoding efficiency.

[0035] Figure 5 is a schematic diagram of the video coding system structure. As shown in Figure 5, the video coding system 100 comprises a transform and quantization module 101, an intra estimation module 102, an intra prediction module 103, a motion compensation module 104, a motion estimation module 105, an inverse transform and inverse quantization module 106, a filter control analysis module 107, a deblocking filtering and sample adaptive offset (SAO) filtering module 108, a header information coding and context-based adaptive binary arithmetic coding (CABAC). Figure 6 is a schematic diagram of the structure of the video decoding system, and as shown in Figure 6, the video decoding system 200 includes components such as a Coding) encoding module 109 and a decoded image cache module 110. The video image undergoes processing in the video encoding system 100, including a transformation and quantization module 101, an intra estimation module 102, an intra prediction module 103, a motion compensation module 104, a motion estimation module 105, a deblocking filtering and SAO filtering module 108, and a header information encoding and CABAC module 109. After processing, the bitstream of the video image is output, which is then input to the video decoding system 200. The video decoding system 200 then undergoes processing in the header information decoding and CABAC decoding module 201, an inverse transformation and inverse quantization module 202, an intra prediction module 203, and a motion compensation module 204, ultimately restoring the original video image.

[0036] The image prediction method according to the present invention can influence the entropy coding process and the entropy decoding process in the coding / decoding process. For example, the image prediction method according to the present invention can be applied to position 109 in the structure of the video coding system shown in Figure 5, and also to position 201 in the structure of the video decoding system shown in Figure 6.

[0037] The technical proposal of the embodiment of this application will be clearly and completely described below with reference to the drawings of the embodiment of this application.

[0038] One embodiment of the present invention provides an image prediction method applied to an encoder, and Figure 7 is a schematic implementation flowchart 1 of the image prediction method, and as shown in Figure 7, the method by which the encoder performs image prediction in the present invention may include the following steps.

[0039] In step 101, if the current block uses MIP mode to determine the intra-predicted value of the current block, the value of the MIP mode parameter is set to indicate that MIP mode should be used and written to the bitstream.

[0040] In embodiments of the present invention, when determining the intra-predicted value of the current block using MIP mode for the current block, the encoder can write the value of the MIP mode parameter to the bitstream, indicating that MIP mode is to be used. The current block can represent the block currently to be encoded or the block currently to be decoded; specifically, in the present invention, when the encoder is encoding, the current block is the block to be encoded.

[0041] Furthermore, in the embodiment of the present invention, when the encoder encodes the current block, it can first select the optimal encoding method in conventional mode and MIP mode.

[0042] In the embodiments of this invention, during the intra-prediction process of the VVC, one optimal mode can be selected from the conventional mode and the MIP mode for any one luminance coding block to perform coding. The conventional modes include Planar mode (number 0), DC mode (number 1), and 67 intra-prediction modes, including 65 types of angle modes.

[0043] Furthermore, in the embodiments of the present invention, when the encoder selects the optimal mode, it can compare the Rdcost of 67 conventional modes and M MIP modes with respect to the current block, thereby selecting the optimal mode and encoding based on the comparison results. The value of M also differs depending on the size type of the current block. Specifically, if the current block is a first type of luminance block, i.e., the size of the current block is 4×4, then M=16; if the current block is a second type of luminance block, i.e., the size of the current block is 8×4, 4×8, or 8×8, then M=8; and if the current block is a third type of luminance block, i.e., the size of the current block is any other, then M=6.

[0044] To be understood, in embodiments of the present application, if the encoder decides to use MIP mode to determine the intra-predicted value of the current block, the encoder may write a value of the MIP mode parameter to the bitstream to indicate the use of MIP mode. That is, the encoder may use a grammar unit to indicate whether the current block uses MIP mode, i.e., the MIP mode parameter is used to indicate whether the current block uses MIP mode.

[0045] Exemplary, in an embodiment of the present invention, after deciding to use MIP mode to determine the intra-predicted value of the current block, the encoder may set the value of the MIP mode parameter to 1 and write it to the bitstream, thereby indicating that the current block will use MIP mode.

[0046] Furthermore, in embodiments of the present invention, if the encoder decides not to use MIP mode to determine the intra-predicted value of the current block, the encoder may write to the bitstream a value of the MIP mode parameter that indicates that MIP mode will not be used.

[0047] Exemplary, in an embodiment of the present invention, after the encoder has decided not to use MIP mode to determine the intra-predicted value of the current block, it may set the value of the MIP mode parameter to 0 and write it to the bitstream, thereby indicating that the current block does not use MIP mode.

[0048] Furthermore, in the embodiments of the present invention, after the encoder has completed setting the values ​​of the MIP mode parameters, it may indicate the MIP mode parameters in one or more grammar units in the bitstream. That is, after the encoder has completed setting the MIP mode parameters depending on whether the current block uses MIP mode, it may indicate the MIP mode parameters in one or more grammar units in the bitstream.

[0049] To be understood, in the embodiments of the present application, the grammar unit indicating the MIP mode parameters may be contained in one or more data units in the bitstream described below: a data unit containing the current block, a slice header information data unit, an image header information data unit, an image layer parameter set, a sequence parameter set, and an adaptive parameter set.

[0050] In the embodiments of this application, one or more data units in the bitstream, including the data unit containing the current block, the slice header information data unit, the image header information data unit, the image layer parameter set, the sequence parameter set, and the adaptive parameter set, can represent MIP mode parameters, and therefore, MIP mode parameters set by the encoder can be adapted to them.

[0051] For example, in this application, when an encoder writes MIP mode parameters to a Sequence Parameter Set (SPS), the MIP mode parameters can be indicated by sps_mip_enable_flag, and therefore, the decoder can determine the MIP mode parameters sps_mip_enable_flag after analyzing the data units of the Sequence Parameter Set in the bitstream.

[0052] Exemplary, in this application, when an encoder writes MIP mode parameters to a Picture Parameter Set (PPS), the MIP mode parameters can be indicated by pps_mip_enable_flag, and therefore, the decoder can determine the MIP mode parameters pps_mip_enable_flag after analyzing the data units of the Picture Parameter Set in the bitstream.

[0053] For example, in this application, when an encoder writes MIP mode parameters to an Adaptive parameter set (APS), the MIP mode parameters can be indicated by aps_mip_enable_flag, and therefore, the decoder can determine the MIP mode parameters aps_mip_enable_flag after analyzing the data units of the Adaptive parameter set in the bitstream.

[0054] For example, in this application, when the encoder writes MIP mode parameters to the slice header information data unit, the MIP mode parameters can be indicated by slice_mip_enable_flag, and therefore the decoder can determine the MIP mode parameters slice_mip_enable_flag after analyzing the data unit of the slice header information data unit in the bitstream.

[0055] In step 102, the MIP mode of the current block is determined, and based on the MIP mode, predicted values ​​for the luminance and chromaticity components corresponding to the current block are determined.

[0056] In the embodiments of the present invention, when determining the intra-predicted values ​​of the current block using the MIP mode for the current block, the encoder can further determine the MIP mode of the current block and then determine the predicted values ​​of the luminance and chromaticity components corresponding to the current block based on the MIP mode.

[0057] As can be understood, in the embodiments of the present application, when the encoder determines the MIP mode corresponding to the current block, it can determine the size type of the current block, then construct a list of candidate MIP modes based on the size type, and finally determine the MIP mode of the current block from the list of candidate MIP modes.

[0058] Furthermore, in the embodiments of the present invention, the current blocks can be divided into three size types based on their size. If the size of the current block is W×H, where W is the width parameter and H is the height parameter, a 4×4 size current block may be determined as the first type of luminance block, that is, the size type of the current block is determined to be the first type. Furthermore, 8×4, 4×8, and 8×8 size current blocks may be determined as the second type of luminance block, that is, the size type of the current block is determined to be the second type. Furthermore, other sizes of current blocks may be determined as the third type of luminance block, that is, the size type of the current block is determined to be the third type.

[0059] As can be understood, in this application, the current block may be of 25 different sizes depending on the height and width parameters. Specifically, although the standard specifies that the maximum size of the luminance block is 128 × 128, the maximum size of the conversion unit is 64 × 64. That is, when the luminance block is 128 × 128 in size, a quadtree division must first be performed, and therefore the maximum size of the luminance block is 64 × 64. Table 1 is a table showing the sizes of the luminance blocks, as shown in Table 1.

[0060] [Table 1]

[0061] Currently, the MIP mode is limited based on the height and width parameters of the current block. Specifically, if the ratio of the width to height of the current block is greater than 4, or if the ratio of the height to width is greater than 4, the current block is not encoded using the MIP mode. Table 2 shows the size limitations of luminance blocks in the MIP mode, as shown in Table 2.

[0062] [Table 2]

[0063] In other words, in this invention, when the encoder determines the size type of the current block, if the width and height of the current block are both equal to 4, i.e., the size of the current block is 4x4, the size type of the current block can be set as the first type; if the width and height of the current block are both equal to 8, i.e., the size of the current block is 8x8, or if the width of the current block is equal to 8 and the height is equal to 4, i.e., the size of the current block is 8x4, or if the width of the current block is equal to 4 and the height is equal to 8, i.e., the size of the current block is 4x8, the size type of the current block can be set as the second type; and if the width and height of the current block do not satisfy the above conditions, i.e., the size of the current block is not 4x4, 8x8, 8x4, or 4x8, the size type of the current block can be set as the third type.

[0064] Furthermore, in the embodiments of the present application, when the encoder determines the size type of the current block based on the size type division method proposed in the current standard, the size type of the current block can be set as the first type if both the width and height of the current block are equal to 4; the size type of the current block can be set as the second type if both the width and height of the current block are equal to 8, or if one of the width and height of the current block is equal to 4; and the size type of the current block can be set as the third type if the width and height of the current block do not satisfy the above conditions, i.e., the width and height of the current block are not simultaneously equal to 4 or 8, or neither the width nor height of the current block is equal to 4.

[0065] In the embodiments of this application, the encoder can construct different candidate MIP mode lists for different size types. Specifically, the MIP technology adds M types of MIP modes to the 67 conventional intra-predictive modes, and the value of M also differs depending on the size type. The value of M may include 16, 8, and 6.

[0066] Exemplary, in this application, if the current block size type is type 1, the value of M is 16, meaning a list of candidate MIP modes can be constructed based on 16 different MIP modes; if the current block size type is type 2, the value of M is 8, meaning a list of candidate MIP modes can be constructed based on 8 different MIP modes; and if the current block size type is type 3, the value of M is 6, meaning a list of candidate MIP modes can be constructed based on 6 different MIP modes.

[0067] Furthermore, in the embodiments of the present invention, the encoder can determine the MIP mode to be used for the current block from the candidate MIP mode list after completing the construction of a list of candidate MIP modes based on the size type of the current block. This allows image prediction processing to be performed on the current block using the MIP mode to obtain an intra-predicted value for the current block.

[0068] As can be understood, in the embodiments of the present invention, the encoder can construct a list of candidate MIP modes corresponding to the current block, select one MIP mode from the list of candidate MIP modes, and then use that MIP mode to determine predicted values ​​for the luminance and chromaticity components corresponding to the current block.

[0069] Specifically, in the embodiment of the present invention, the encoder can first read the mode number k of the MIP mode from the candidate MIP mode list, thereby obtaining the corresponding matrix Ak and offset amount bk. Based on the above formula (1), matrix-vector multiplication can be performed to obtain the predicted luminance component value corresponding to the current block.

[0070] In this embodiment, the encoder can determine the MIP mode of the current block from the candidate MIP mode list, then set the MIP mode index number of the current block based on the MIP mode of the current block, and write the MIP mode index number to the bitstream.

[0071] As can be understood, in this application, the MIP mode index number of the current block may be used to indicate the specific MIP mode used by the current block. That is, on the encoding side, the encoder sets the MIP mode index number of the current block and writes it to the bitstream, then transmits it to the decoding side, and the decoder analyzes the bitstream to obtain the MIP mode index number of the current block, thereby determining the MIP mode indicated by the MIP mode index number from the list of candidate MIP modes of the current block.

[0072] In step 103, the MIP mode of the current block is written to the bitstream.

[0073] In the embodiment of the present invention, the encoder can determine the MIP mode of the current block, and after determining the predicted values ​​of the luminance and chromaticity components corresponding to the current block based on the MIP mode, write the MIP mode of the current block to the bitstream.

[0074] In other words, in the implementation process of encoding the current block, the encoder not only needs to write to the compressed bitstream whether the current block uses MIP mode, but also needs to write to the bitstream which specific mode to use, for example, which specific MIP mode to use when performing intra prediction using MIP mode.

[0075] Embodiments of the present invention provide an image prediction method in which, when the current block uses MIP mode to determine the intra-predicted value of the current block, the encoder sets the value of the MIP mode parameter to indicate the use of MIP mode and writes it to the bitstream, determines the MIP mode of the current block, determines the predicted values ​​of the luminance component and chromaticity component corresponding to the current block based on the MIP mode, and writes the MIP mode of the current block to the bitstream. That is, in embodiments of the present invention, when the encoder performs intra-prediction on the current block, if it determines that the current block uses MIP mode, it can obtain the intra-predicted value of the current block using MIP mode, set the MIP mode parameter and write it to the bitstream for transmission to the decoding side, and the decoder can analyze the bitstream to obtain the MIP mode parameter, and if the MIP mode parameter indicates that the current block uses MIP mode, the decoder can determine the intra-predicted value of the current block using MIP mode. As can be seen from the above, the image prediction method according to the present invention can use a grammar unit to indicate whether the current block in the bitstream is using MIP mode, thereby simplifying the image prediction process, reducing complexity in ensuring encoding / decoding performance, decreasing the memory space and overall time required for the encoding / decoding process, and effectively improving encoding / decoding efficiency.

[0076] Based on the embodiments described above, further embodiments of the present invention provide an image prediction method in which, when an encoder decides to use MIP mode to predict the intra-predicted value of the current block, MIP mode parameters can be written to one or more grammar elements in the bitstream to indicate whether the current block uses MIP mode. That is, in the present invention, the VVC bitstream transmits one or more grammar elements to enable or disable MIP mode. The grammar elements may be located in the video sequence layer, picture layer and / or sub-picture layer, or in data units in the slice / tile / brick layer, where a sub-picture refers to an area covering a portion of a picture.

[0077] Exemplary, in this application, the encoder can determine whether to use MIP mode when encoding a video sequence. The entropy coding unit can encode flags in a parameter set that may be relevant to all slices in the video sequence. Table 3 shows an example of implementation in a sequence parameter set (SPS) of a grammatical structure, where u(1) shows the entropy coding method described in detail in the VVC working draft.

[0078] [Table 3]

[0079] According to Table 3 above, if the encoder decides not to use MIP mode when encoding the input video sequence, the entropy coding unit can set sps_mip_enable_flag to equal to 0 and write the value to the SPS (indirectly associated with the slices in the video sequence); if the encoder decides to use MIP mode when encoding one or more slices in the input video sequence, the entropy coding unit can set sps_mip_enable_flag to equal to 1 and write the value to the SPS (indirectly associated with the slices in the video sequence).

[0080] In other words, in this application, after completing the setting of the value of the MIP mode parameter sps_mip_enable_flag, the encoder may indicate the MIP mode parameter in one or more grammar units in the bitstream. That is, after completing the setting of the MIP mode parameter sps_mip_enable_flag, depending on whether the current block uses MIP mode, the encoder may write the MIP mode parameter sps_mip_enable_flag to the sequence parameter set in the bitstream.

[0081] Exemplary, in this application, the encoder can determine whether to use MIP mode when encoding a picture or a subpicture in a video sequence. The entropy encoding unit can encode flags in a parameter set that may be relevant to all slices in the picture or subpicture. Table 4 shows an example of implementation in the picture parameter set (PPS) of the grammatical structure, where u(1) shows the entropy encoding method described in detail in the VVC working draft.

[0082] [Table 4]

[0083] According to Table 4 above, if the encoder decides not to use MIP mode when encoding a picture or subpicture, the entropy coding unit can set pps_mip_enable_flag to equal to 0 and write the value to the PPS associated with the slice in the picture or subpicture. If the encoder decides to use MIP mode when encoding one or more slices in a picture or subpicture, the entropy coding unit can set pps_mip_enable_flag to equal to 1 and write the value to the PPS associated (indirectly) with the slice in the picture or subpicture.

[0084] In other words, in this application, after completing the setting of the value of the MIP mode parameter pps_mip_enable_flag, the encoder may indicate the MIP mode parameter in one or more grammar units in the bitstream. That is, after completing the setting of the MIP mode parameter pps_mip_enable_flag, depending on whether the current block uses MIP mode, the encoder may write the MIP mode parameter pps_mip_enable_flag to the picture parameter set in the bitstream.

[0085] Exemplary, in this application, the encoder can determine whether to use MIP mode when encoding a picture or a subpicture in a video sequence. The entropy encoding unit can encode flags in a parameter set that may be relevant to all slices in the picture or subpicture. Table 5 shows an example of implementation in the Adaptive Parameter Set (APS) of the grammatical structure, where u(1) shows the entropy encoding method described in detail in the VVC working draft.

[0086] [Table 5]

[0087] According to Table 5 above, if the encoder decides not to use MIP mode when encoding a picture or subpicture, the entropy coding unit can set aps_mip_enable_flag to equal to 0 and write the value to the APS associated with the slice in the picture or subpicture. If the encoder decides to use MIP mode when encoding one or more slices in a picture or subpicture, the entropy coding unit can set aps_mip_enable_flag to equal to 1 and write the value to the APS associated (indirectly) with the slice in the picture or subpicture.

[0088] In other words, in this application, after completing the setting of the value of the MIP mode parameter aps_mip_enable_flag, the encoder may indicate the MIP mode parameter in one or more grammar units in the bitstream. That is, after completing the setting of the MIP mode parameter aps_mip_enable_flag, depending on whether the current block uses MIP mode, the encoder may write the MIP mode parameter aps_mip_enable_flag to the adaptive parameter set in the bitstream.

[0089] [Table 6]

[0090] Exemplary, in this application, the encoder can determine whether to use MIP mode when encoding a slice. The entropy encoding unit can encode flags in the slice header. Table 6 shows an example of implementation of a grammar structure in the slice header, where u(1) shows the entropy encoding method described in detail in the VVC working draft.

[0091] According to Table 6 above, if the encoder decides not to use MIP mode when encoding a slice, the entropy coding unit can set slice_mip_enable_flag to equal to 0 and write the value to the slice header. If the encoder decides to use MIP mode when encoding a slice, the entropy coding unit can set slice_mip_enable_flag to equal to 1 and write the value to the slice header.

[0092] In other words, in this application, after completing the setting of the value of the MIP mode parameter slice_mip_enable_flag, the encoder may indicate the MIP mode parameter in one or more grammar units in the bitstream. That is, after completing the setting of the MIP mode parameter slice_mip_enable_flag depending on whether the current block uses MIP mode, the encoder may write the MIP mode parameter slice_mip_enable_flag to the slice header information data unit in the bitstream.

[0093] Exemplary, in this application, when encoding a tile or brick, the encoder determines whether to use MIP mode, and the entropy encoding unit may write similar MIP mode parameters to it as part of a parameter set indicating the division of the tile or brick in the picture or subpicture. Optionally, the entropy encoding unit may write even more similar MIP mode parameters to the slice data associated with the tile or brick in the slice to indicate whether to use MIP mode when encoding the tile or brick.

[0094] Exemplary, in this application, the encoder may decide to use MIP mode when encoding a portion of a picture or subpicture in a video sequence. The entropy encoding unit may encode sps_mip_enable_flag in SPS to 1, encode pps_mip_enable_flag in PPS or aps_mip_enable_flag in APS to 1, relating to a slice in the picture or subpicture, and encode pps_mip_enable_flag in PPS or aps_mip_enable_flag in APS to 0, relating to other pictures or subpictures in the video sequence. As an option, the entropy coding unit can encode the slice_mip_enable_flag (or a similar MIP mode parameter for tiles or bricks in the slice data) of a slice in a picture or subpicture to 1, or encode the slice_mip_enable_flag (or a similar MIP mode parameter for tiles or bricks in the slice data) of a slice in a picture or subpicture to 0.

[0095] Exemplary, the present invention may further implicitly communicate whether the MIP mode is used to encode a video sequence in other grammatical elements (e.g., grammatical elements indicating rank / grade / level (PTL) in one or more parameter sets of a bitstream or sub-bitstream). For example, the encoder may set the MIP mode to be disabled in one or more PTLs and enabled in other PTLs.

[0096] As can be understood, in this application, if the encoder now transmits instructions to the bitstream to encode using MIP mode, the decoder can correspondingly decode the bitstream using MIP mode.

[0097] Embodiments of the present invention provide an image prediction method in which, when the current block uses MIP mode to determine the intra-predicted value of the current block, the encoder sets the value of the MIP mode parameter to indicate the use of MIP mode and writes it to the bitstream, determines the MIP mode of the current block, determines the predicted values ​​of the luminance component and chromaticity component corresponding to the current block based on the MIP mode, and writes the MIP mode of the current block to the bitstream. That is, in embodiments of the present invention, when the encoder performs intra-prediction on the current block, if it determines that the current block uses MIP mode, it can obtain the intra-predicted value of the current block using MIP mode, set the MIP mode parameter and write it to the bitstream for transmission to the decoding side, and the decoder can analyze the bitstream to obtain the MIP mode parameter, and if the MIP mode parameter indicates that the current block uses MIP mode, the decoder can determine the intra-predicted value of the current block using MIP mode. As can be seen from the above, the image prediction method according to the present invention can use a grammar unit to indicate whether the current block in the bitstream is using MIP mode, thereby simplifying the image prediction process, reducing complexity in ensuring encoding / decoding performance, decreasing the memory space and overall time required for the encoding / decoding process, and effectively improving encoding / decoding efficiency.

[0098] Based on the above embodiment, one embodiment of the present application provides an image prediction method that is applied to a decoder, and Figure 8 is a schematic implementation flowchart 2 of the image prediction method, and as shown in Figure 8, in the present application, the method by which the decoder performs image prediction may include the following steps.

[0099] In step 201, the bitstream is analyzed to determine the MIP mode parameters of the current block.

[0100] In the embodiments of the present invention, the decoder analyzes the bitstream to determine the MIP mode parameters of the current block. The current block can represent the block currently to be encoded or the block currently to be decoded. Specifically, in the present invention, when the decoder decodes, the current block is the block to be decoded.

[0101] As can be understood, in the embodiments of the present application, the decoder can parse one or more grammar units in the bitstream, thereby determining the MIP mode parameters of the current block. That is, in the present application, the MIP mode parameters can be represented by one or more grammar units in the bitstream.

[0102] Furthermore, in the embodiments of the present invention, the grammar unit indicating the MIP mode parameters may be included in one or more data units in the bitstream described below: a data unit containing the current block, a slice header information data unit, an image header information data unit, an image layer parameter set, a sequence parameter set, and an adaptive parameter set.

[0103] In the embodiments of this application, the MIP mode parameter is used to indicate whether the current block uses MIP mode. Specifically, if the MIP mode parameter indicates that MIP mode is used, the decoder can use MIP mode to determine the intra-predicted value of the current block; if the MIP mode parameter indicates that MIP mode is not used, the decoder does not use MIP mode to determine the intra-predicted value of the current block.

[0104] Furthermore, in the embodiments of the present invention, the decoder can analyze the bitstream to determine the MIP mode parameters and then determine whether the current block uses MIP mode based on the values ​​of the MIP mode parameters.

[0105] Exemplary, in an embodiment of the present invention, after determining the MIP mode parameter, the decoder may indicate that the current block will use MIP mode if the value of the MIP mode parameter is 1, and the decoder can then use MIP mode to determine the intra-predicted value of the current block.

[0106] Exemplary, in an embodiment of the present invention, after determining the MIP mode parameter, if the value of the MIP mode parameter is 0, the decoder may indicate that the current block does not use MIP mode, and in that case, the decoder does not use MIP mode to determine the intra-predicted value of the current block.

[0107] In the embodiments of this invention, one or more data units in the bitstream, including the data unit containing the current block, the slice header information data unit, the image header information data unit, the image layer parameter set, the sequence parameter set, and the adaptive parameter set, can represent MIP mode parameters, and therefore, the MIP mode parameters analyzed and obtained by the decoder can be adapted to them.

[0108] Exemplary, in this application, when the encoder writes MIP mode parameters to the sequence parameter set, the MIP mode parameters can be indicated by sps_mip_enable_flag, and therefore the decoder can determine the MIP mode parameters sps_mip_enable_flag after analyzing the data units of the sequence parameter set in the bitstream.

[0109] Exemplary, in this application, when the encoder writes MIP mode parameters to the picture parameter set, the MIP mode parameters can be indicated by pps_mip_enable_flag, and therefore the decoder can determine the MIP mode parameters pps_mip_enable_flag after analyzing the data units of the picture parameter set in the bitstream.

[0110] For example, in this application, when the encoder writes MIP mode parameters to the adaptive parameter set, the MIP mode parameters can be indicated by aps_mip_enable_flag, and therefore the decoder can determine the MIP mode parameters aps_mip_enable_flag after analyzing the data units of the adaptive parameter set in the bitstream.

[0111] For example, in this application, when the encoder writes MIP mode parameters to the slice header information data unit, the MIP mode parameters can be indicated by slice_mip_enable_flag, and therefore the decoder can determine the MIP mode parameters slice_mip_enable_flag after analyzing the data unit of the slice header information data unit in the bitstream.

[0112] In step 202, if the value of the MIP mode parameter indicates that the current block uses the MIP mode to determine the intra-predicted value of the current block, the bitstream is analyzed to determine the MIP mode of the current block, and based on the MIP mode, the predicted values ​​of the luminance and chromaticity components corresponding to the current block are determined.

[0113] In embodiments of the present invention, after analyzing the bitstream to determine the MIP mode parameter of the current block, if the value of the MIP mode parameter indicates that the current block uses the MIP mode to determine the intra-predicted value of the current block, the decoder can continue to analyze the bitstream to determine the MIP mode of the current block and then determine the predicted values ​​of the luminance and chromaticity components corresponding to the current block based on the MIP mode.

[0114] As can be understood, in the embodiments of the present application, after the decoder analyzes the bitstream to determine the MIP mode parameter for the current block, the decoder does not use MIP mode for the current block if the value of the MIP mode parameter indicates that the MIP mode is not used to determine the intra-predicted value for the current block.

[0115] In other words, in the implementation process of decoding the current block, the decoder analyzes the bitstream. Not only can it obtain an MIP mode parameter indicating whether the current block uses MIP mode, but it can also determine which mode the current block written to the bitstream specifically uses, for example, which specific MIP mode to use when performing intra prediction using MIP mode.

[0116] Furthermore, in the embodiments of the present invention, in the intra-prediction process of the VVC, one optimal mode can be selected from the conventional mode and the MIP mode for any one luminance coding block and the coding process can be performed. The conventional mode consists of 67 intra-prediction modes, including the Planar mode (number 0), the DC mode (number 1), and 65 types of angle modes.

[0117] In this embodiment, when the decoder determines the intra-predicted value of the current block using the MIP mode, it can analyze the bitstream to determine the MIP mode of the current block, and then determine the predicted values ​​of the luminance and chromaticity components corresponding to the current block based on the MIP mode.

[0118] To be understood, in the embodiments of the present invention, when the decoder analyzes the bitstream to determine the MIP mode of the current block, it can first analyze the bitstream to obtain the MIP mode index number of the current block, then determine the size type of the current block, and then select the MIP mode indicated by the MIP mode index number from a list of candidate MIP modes corresponding to the size type as the MIP mode of the current block.

[0119] Furthermore, in the embodiments of the present invention, the MIP mode index number of the current block may be used to indicate the specific MIP mode used by the current block. That is, on the encoding side, the encoder sets the MIP mode index number of the current block and writes it to the bitstream, then transmits it to the decoding side, and the decoder analyzes the bitstream and obtains the MIP mode index number of the current block, which allows it to determine the MIP mode indicated by the MIP mode index number from the list of candidate MIP modes for the current block.

[0120] In the embodiment of this invention, when the decoder determines the MIP mode of the current block, it can first determine the size type of the current block. Specifically, according to Table 2 above, when the decoder determines the size type of the current block, if the width and height of the current block are both equal to 4, i.e., the size of the current block is 4×4, the decoder can set the size type of the current block as the first type; if the width and height of the current block are both equal to 8, i.e., the size of the current block is 8×8, or the width of the current block is equal to 8 and the height is equal to 4, i.e., the size of the current block is 8×4, or the width of the current block is equal to 4 and the height is equal to 8, i.e., the size of the current block is 4×8, the decoder can set the size type of the current block as the second type; and if the width and height of the current block do not satisfy the above conditions, i.e., the size of the current block is not 4×4, 8×8, 8×4, or 4×8, the decoder can set the size type of the current block as the third type.

[0121] Furthermore, in the embodiments of the present application, when determining the size type of the current block based on the size type division method proposed in the current standard, the encoder can set the size type of the current block as the first type if both the width and height of the current block are equal to 4, set the size type of the current block as the second type if both the width and height of the current block are equal to 8, or if one of the width and height of the current block is equal to 4, and set the size type of the current block as the third type if the width and height of the current block do not satisfy the above conditions, i.e., the width and height of the current block are not simultaneously equal to 4 or 8, or neither the width nor height of the current block is equal to 4.

[0122] As can be understood, in the embodiments of the present application, for different size types, the decoder can construct different candidate MIP mode lists. Specifically, the MIP technology adds M types of MIP modes to the 67 conventional intra-predictive modes, and the value of M also differs depending on the different size type. The value of M may include 16, 8, and 6.

[0123] Exemplary, in this application, if the current block size type is type 1, the value of M is 16, meaning a list of candidate MIP modes can be constructed based on 16 different MIP modes; if the current block size type is type 2, the value of M is 8, meaning a list of candidate MIP modes can be constructed based on 8 different MIP modes; and if the current block size type is type 3, the value of M is 6, meaning a list of candidate MIP modes can be constructed based on 6 different MIP modes.

[0124] Exemplary, in the embodiment of the present invention, the decoder can first read the mode number k of the MIP mode from the candidate MIP mode list, thereby obtaining the corresponding matrix Ak and offset amount bk, and thereby perform matrix-vector multiplication based on formula (1) above to obtain the predicted luminance component value corresponding to the current block.

[0125] In step 203, the current block is decoded based on the predicted value.

[0126] In the embodiments of the present invention, the decoder can analyze the bitstream to determine the MIP mode of the current block, and then, based on the MIP mode, determine predicted values ​​for the luminance and chromaticity components corresponding to the current block, and then decode the current block based on the predicted values ​​for the luminance and chromaticity components.

[0127] Embodiments of the present invention provide an image prediction method in which a decoder analyzes a bitstream to determine the MIP mode parameter of the current block, and if the value of the MIP mode parameter indicates that the current block will use MIP mode to determine the intra-predicted value of the current block, the decoder analyzes the bitstream to determine the MIP mode of the current block, and based on the MIP mode, determines the predicted values ​​of the luminance component and chromaticity component corresponding to the current block, and decodes the current block based on the predicted values. That is, in embodiments of the present invention, when an encoder performs intra-prediction on the current block, if it decides that the current block will use MIP mode, it can obtain the intra-predicted value of the current block using MIP mode, set the MIP mode parameter, write it to the bitstream and transmit it to the decoder, and the decoder analyzes the bitstream to obtain the MIP mode parameter, and if the MIP mode parameter indicates that the current block will use MIP mode, the decoder can determine the intra-predicted value of the current block using MIP mode. As can be seen from the above, the image prediction method according to the present invention can use a grammar unit to indicate whether the current block in the bitstream is using MIP mode, thereby simplifying the image prediction process, reducing complexity in ensuring encoding / decoding performance, decreasing the memory space and overall time required for the encoding / decoding process, and effectively improving encoding / decoding efficiency.

[0128] Based on the embodiments described above, other embodiments of the present invention provide an image prediction method in which a decoder can analyze a bitstream to obtain one or more grammatical elements to indicate whether the current block uses MIP mode to determine the predicted value of the current block. Furthermore, in the present invention, the decoder can analyze the obtained one or more grammatical elements to indicate whether to use MIP mode when decoding a video sequence, one or more pictures, slices, tiles, or bricks. That is, in the present invention, a VVC bitstream transmits one or more grammatical elements to enable or disable MIP mode. The grammatical elements may be located in the video sequence layer, picture layer and / or subpicture layer, or data units in the slice / tile / brick layer, where a subpicture refers to an area covering a portion of a picture.

[0129] Exemplary, in this application, the decoder can obtain MIP mode parameters from a parameter set associated with all slices in a video sequence. Specifically, the decoder can obtain MIP mode parameters from an SPS. Table 3 above shows an example of the implementation of a grammatical structure in an SPS, where u(1) shows the entropy decoding method described in detail in the VVC working draft.

[0130] If the decoder determines that the value of the MIP mode parameter sps_mip_enable_flag is equal to 0, the decoder will not use MIP mode when decoding slices (indirectly) associated with the SPS. If the decoder determines that the value of the MIP mode parameter sps_mip_enable_flag is equal to 1, the decoder will use MIP mode when decoding slices (indirectly) associated with the SPS.

[0131] In other words, in this invention, the decoder can determine the MIP mode parameter sps_mip_enable_flag after analyzing the sequence parameter set in the bitstream, and then determine whether the current block is to be decoded using MIP mode based on the value of the MIP mode parameter sps_mip_enable_flag.

[0132] Exemplary, in this application, the decoder can obtain MIP mode parameters from a parameter set associated with all slices in a picture or subpicture in a video sequence. Specifically, the decoder can obtain MIP mode parameters from a PPS. Table 4 above shows an example of the implementation of the grammatical structure in the PPS, where u(1) shows the entropy decoding method described in detail in the VVC working draft.

[0133] If the decoder determines that the value of the MIP mode parameter pps_mip_enable_flag is equal to 0, the decoder will not use MIP mode when decoding the slice associated with the PPS. If the decoder determines that the value of the MIP mode parameter pps_mip_enable_flag is equal to 1, the decoder will use MIP mode when decoding the slice associated with the PPS.

[0134] In other words, in this invention, the decoder can determine the MIP mode parameter pps_mip_enable_flag after analyzing the picture parameter set in the bitstream, and then determine whether the current block is to be decoded using MIP mode based on the value of the MIP mode parameter pps_mip_enable_flag.

[0135] Exemplary, in this application, the decoder can obtain MIP mode parameters from a parameter set associated with all slices in a picture or subpicture in a video sequence. Specifically, the decoder can obtain MIP mode parameters from an APS. Table 5 above shows an example of implementation in the sequence parameter set APS of the grammatical structure, where u(1) shows the entropy decoding method described in detail in the VVC working draft.

[0136] If the decoder determines that the value of the MIP mode parameter aps_mip_enable_flag is equal to 0, the decoder will not use MIP mode when decoding the slice associated with the APS. If the decoder determines that the value of the MIP mode parameter aps_mip_enable_flag is equal to 1, the decoder will use MIP mode when decoding the slice associated with the APS.

[0137] In other words, in this invention, the decoder can determine the MIP mode parameter aps_mip_enable_flag after analyzing the adaptive parameter set in the bitstream, and then determine whether the current block is to be decoded using MIP mode based on the value of the MIP mode parameter aps_mip_enable_flag.

[0138] Exemplary, in this application, the decoder can obtain MIP mode parameters from the slice header. Table 6 above shows an example of implementation in the slice header of the grammar structure, where u(1) shows the entropy decoding method described in detail in the VVC working draft.

[0139] If the decoder determines that the value of the MIP mode parameter slice_mip_enable_flag is equal to 0, the decoder will not use MIP mode when decoding the slice. If the decoder determines that the value of the MIP mode parameter slice_mip_enable_flag is equal to 1, the decoder will use MIP mode when decoding the slice.

[0140] In other words, in this invention, the decoder can analyze the slice header information data unit in the bitstream, determine the MIP mode parameter slice_mip_enable_flag, and then determine whether the current block is to be decoded using MIP mode based on the value of the MIP mode parameter slice_mip_enable_flag.

[0141] Exemplary, in the present invention, when decoding a tile or brick, the decoder may obtain similar MIP mode parameters, which, as part of a parameter set indicating the division of a picture or subpicture tile or brick, indicate whether to use MIP mode when encoding the tile or brick of the picture or subpicture. Alternatively, the decoder may further obtain similar MIP mode parameters from slice data relating to the tile or brick in the slice, thereby indicating whether to use MIP mode when encoding the tile or brick.

[0142] Exemplary, in this application, the decoder can obtain various MIP mode parameters from different data units in the input bitstream. The decoder can obtain that sps_mip_enable_flag in SPS is equal to 1, that pps_mip_enable_flag in PPS or aps_mip_enable_flag in APS is equal to 1 for slices in a picture or subpicture, and that pps_mip_enable_flag in PPS or aps_mip_enable_flag in APS is equal to 0 for other pictures or subpictures. In such a case, the decoder can use MIP mode when decoding some pictures or subpictures in the input bitstream, and not use MIP mode when decoding other pictures or subpictures. Alternatively, the decoder may obtain from the slice header of a slice in a picture or subpicture that slice_mip_enable_flag (or a similar MIP mode parameter for tiles or bricks in the slice data) is equal to 1, and the decoder may use MIP mode when decoding that slice. The decoder may also obtain from the slice header of another slice in a picture or subpicture that slice_mip_enable_flag (or a similar MIP mode parameter for tiles or bricks in the slice data) is equal to 0, and the decoder may not use MIP mode when decoding that slice.

[0143] Exemplary, in this application, the decoder can be implicitly informed whether the MIP mode is used to decode an input bitstream from another grammar element (e.g., a grammar element of a PTL in one or more parameter sets indicating a bitstream or subbitstream). For example, the MIP mode may be set to disabled when decoding on one or more PTLs, but enabled when decoding on other PTLs.

[0144] Embodiments of the present invention provide an image prediction method in which a decoder analyzes a bitstream to determine the MIP mode parameter of the current block, and if the value of the MIP mode parameter indicates that the current block will use MIP mode to determine the intra-predicted value of the current block, the decoder analyzes the bitstream to determine the MIP mode of the current block, and based on the MIP mode, determines the predicted values ​​of the luminance component and chromaticity component corresponding to the current block, and decodes the current block based on the predicted values. That is, in embodiments of the present invention, when an encoder performs intra-prediction on the current block, if it decides that the current block will use MIP mode, it can obtain the intra-predicted value of the current block using MIP mode, set the MIP mode parameter, write it to the bitstream and transmit it to the decoder, and the decoder analyzes the bitstream to obtain the MIP mode parameter, and if the MIP mode parameter indicates that the current block will use MIP mode, the decoder can determine the intra-predicted value of the current block using MIP mode. As can be seen from the above, the image prediction method according to the present invention can use a grammar unit to indicate whether the current block in the bitstream is using MIP mode, thereby simplifying the image prediction process, reducing complexity in ensuring encoding / decoding performance, decreasing the memory space and overall time required for the encoding / decoding process, and effectively improving encoding / decoding efficiency.

[0145] Based on the above embodiments, in further embodiments of the present application, the encoder and decoder embodiments described in the above embodiments can be configured to enable the MIP mode during the session negotiation process, for example.

[0146] Exemplary, in the first exemplary system, a transmitter equipped with an encoder generates a bitstream for the receiver based on the receiver's processing capabilities. For example, during session negotiation, if the transmitter determines that the receiver cannot smoothly enable MIP mode and process the bitstream (or if the receiver notifies the transmitter that it cannot smoothly enable MIP mode and decode the bitstream), the transmitter generates the bitstream with MIP mode disabled, for example by setting sps_mip_enable_flag to equal to 0.

[0147] Exemplary, a second exemplary system comprises a transmitter that stores multiple bitstreams that use MIP mode when decoding all or different parts of the bitstream. When negotiating a session, if the transmitter determines that the receiver cannot smoothly enable MIP mode and process the bitstream (or if the receiver notifies the transmitter that it cannot smoothly enable MIP mode and decode the bitstream), the transmitter sends a bitstream in which MIP mode is disabled by choice, for example, a bitstream in which sps_mip_enable_flag is equal to 0.

[0148] Exemplary, a third exemplary system is a real-time communication system, such as a video conferencing system, video phone, or live video bitstream. Unlike the first exemplary system, the receiver is not always unable to process a bitstream encoded using MIP mode. For example, the receiver may have a battery. If the energy in the battery is below a threshold (e.g., 20% of the total power), the receiver notifies the transmitter that it cannot process a bitstream encoded using MIP mode due to insufficient energy. Upon receiving a request from the receiver, the transmitter generates a bitstream by disabling MIP mode, for example, by starting a new encoded video sequence (CVS) with a new SPS containing sps_mip_enable_flag equal to 0, or by generating a new PPS or APS containing the MIP enable flag (MIP mode parameter) equal to 0, or by setting the MIP enable flag in the slice header (or other similar grammatical element of a tile or brick) to equal to 0. When the receiver charges its battery, it can notify the transmitter that it is ready to process a bitstream to be encoded using MIP mode. In such a case, the transmitter can generate the bitstream using MIP mode and set corresponding flags in the SPS, PPS, APS, or slice header. Alternatively, the transmitter can satisfy the receiver's request by switching between different rails containing different bitstreams generated by different MIP mode settings.

[0149] Embodiments of the present invention provide an image prediction method in which, when an encoder performs intraprediction on the current block, if it decides that the current block uses MIP mode, it can obtain an intrapredicted value for the current block using MIP mode, set MIP mode parameters, write them to the bitstream, and transmit them to the decoding side. The decoder analyzes the bitstream to obtain MIP mode parameters, and if the MIP mode parameters indicate that the current block uses MIP mode, the decoder can determine an intrapredicted value for the current block using MIP mode. As can be seen from the above, the image prediction method according to the present invention can use a grammar unit to indicate in the bitstream whether the current block uses MIP mode, thereby simplifying the image prediction process, reducing complexity in ensuring encoding / decoding performance, decreasing the memory space and overall time required for the encoding / decoding process, and effectively improving encoding / decoding efficiency.

[0150] Based on the above embodiment, in a further embodiment of the present application, Figure 9 is a schematic diagram 1 of the configuration of an encoder according to an embodiment of the present application, and as shown in Figure 9, the encoder 300 according to an embodiment of the present application may include a setting unit 301, a first determination unit 302, and an encoding unit 303. The setting unit 301 is configured to write to the bitstream a value of the MIP mode parameter to indicate that the MIP mode should be used when the current block uses MIP mode to determine the intra-predicted value of the current block. The first determination unit 302 is configured to determine the MIP mode of the current block and to determine predicted values ​​of the luminance component and chromaticity component corresponding to the current block based on the MIP mode. The encoding unit 303 is configured to write the MIP mode of the current block to the bitstream.

[0151] Furthermore, in the embodiment of the present application, the setting unit 301 is further configured to write to the bitstream a value of the MIP mode parameter that indicates that the MIP mode will not be used, if the current block does not use the MIP mode to determine the intra-predicted value of the current block.

[0152] Furthermore, in the embodiments of the present invention, the MIP mode parameters are represented in one or more grammar units in the bitstream.

[0153] Furthermore, in the embodiments of the present application, the grammar unit is comprised of one or more data units in the bitstream described below: a data unit containing the current block, a slice header information data unit, an image header information data unit, an image layer parameter set, a sequence parameter set, and an adaptive parameter set.

[0154] Furthermore, in the embodiment of the present application, the first determination unit 302 is configured to specifically determine the size type of the current block, construct the candidate MIP mode list based on the size type, and determine the MIP mode of the current block from the candidate MIP mode list.

[0155] Furthermore, in the embodiments of the present application, the first determination unit 302 is configured to construct the candidate MIP mode list based on 16 types of MIP modes when the current block size type is a first type, to construct the candidate MIP mode list based on 8 types of MIP modes when the current block size type is a second type, and to construct the candidate MIP mode list based on 6 types of MIP modes when the current block size type is a third type.

[0156] Furthermore, in the embodiment of the present application, the first determination unit 302 is configured to set the size type of the current block as the first type if the width and height of the current block are both equal to 4, to set the size type of the current block as the second type if the width and height of the current block are both equal to 8, or the width of the current block is equal to 8 and the height is equal to 4, or the width of the current block is equal to 4 and the height is equal to 8, and to set the size type of the current block as the third type if the width and height of the current block do not satisfy the above conditions.

[0157] Furthermore, in the embodiment of the present application, the first determination unit 302 is configured to set the size type of the current block as the first type if both the width and height of the current block are equal to 4, to set the size type of the current block as the second type if both the width and height of the current block are equal to 8, or if one of the width and height of the current block is equal to 4, and to set the size type of the current block as the third type if the width and height of the current block do not satisfy the above conditions.

[0158] Figure 10 is a schematic diagram of the configuration of an encoder according to an embodiment of the present application. As shown in Figure 10, the encoder 300 according to an embodiment of the present application may further include a first processor 304, a first memory 305 in which executable instructions of the first processor 304 are stored, a first communication interface 306, and a first bus 307 for connecting the first processor 304, the first memory 305, and the first communication interface 306.

[0159] Furthermore, in the embodiments of the present application, the first processor 304 is used to write to the bitstream a value of the MIP mode parameter that indicates the use of MIP mode when the current block uses MIP mode to determine the intra-predicted value of the current block; to determine the MIP mode of the current block and determine the predicted values ​​of the luminance component and chromaticity component corresponding to the current block based on the MIP mode; and to write the MIP mode of the current block to the bitstream.

[0160] Furthermore, in this embodiment, each functional module may be integrated into a single processing unit, each unit may exist physically independently, and two or more units may be integrated into a single unit. The integrated unit may be implemented in hardware form or in the form of a software functional module.

[0161] The integrated unit may be implemented in the form of a software function module and, when sold or used as an independent product, may be stored on a single computer-readable storage medium. Based on this understanding, the essential or prior art contribution of the proposed technology of this embodiment, or all or part of the proposed technology, may be embodied in the form of a software product. The computer software product is stored on a single storage medium containing some instructions for causing a single computer device (which may be a personal computer, server, or network device, etc.) or processor to perform all or part of the steps of the method of this embodiment. The storage medium may include various media capable of storing program code, such as USB memory, portable hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0162] Embodiments of the present invention provide an image encoder which, when the current block uses MIP mode to determine the intra-predicted value of the current block, writes the value of the MIP mode parameter to the bitstream, sets it to indicate the use of MIP mode, determines the MIP mode of the current block, determines the predicted values ​​of the luminance and chromaticity components corresponding to the current block based on the MIP mode, and writes the MIP mode of the current block to the bitstream. A decoder analyzes the bitstream to determine the MIP mode parameter of the current block, and when the value of the MIP mode parameter indicates that the current block uses MIP mode to determine the intra-predicted value of the current block, analyzes the bitstream to determine the MIP mode of the current block, determines the predicted values ​​of the luminance and chromaticity components corresponding to the current block based on the MIP mode, and decodes the current block based on the predicted values. In other words, in the embodiment of the present invention, when the encoder performs intraprediction on the current block, if it decides that the current block will use MIP mode, it can obtain the intrapredicted value of the current block using MIP mode, set the MIP mode parameters, write them to the bitstream, and transmit them to the decoding side. The decoder analyzes the bitstream to obtain the MIP mode parameters, and if the MIP mode parameters indicate that the current block will use MIP mode, the decoder can determine the intrapredicted value of the current block using MIP mode. As can be seen from the above, the image prediction method according to the present invention can use a grammar unit to indicate in the bitstream whether the current block will use MIP mode, thereby simplifying the image prediction process, reducing complexity in ensuring encoding / decoding performance, decreasing the memory space and overall time required for the encoding / decoding process, and effectively improving encoding / decoding efficiency.

[0163] Based on the above embodiment, in another embodiment of the present application, Figure 11 is a schematic diagram of the configuration of a decoder according to an embodiment of the present application, and as shown in Figure 11, the decoder 400 according to an embodiment of the present application may include a decoding unit 401 and a second determination unit 402. The decoding unit 401 is configured to analyze the bitstream and determine the MIP mode parameter of the current block, and to analyze the bitstream and determine the MIP mode of the current block if the value of the MIP mode parameter indicates that the current block uses the MIP mode to determine the intra-predicted value of the current block. The second determination unit 402 is configured to determine predicted values ​​of the luminance component and chromaticity component corresponding to the current block based on the MIP mode, The decoding unit 401 is further configured to decode the current block based on the predicted value.

[0164] Furthermore, in the embodiments of the present application, the second determination unit 402 is further configured to analyze the bitstream to determine the MIP mode parameter of the current block, and then determine that the current block does not use the MIP mode if the value of the MIP mode parameter indicates that the current block does not use the MIP mode to determine the intra-predicted value of the current block.

[0165] Furthermore, in the embodiments of the present invention, the MIP mode parameters are represented in one or more grammar units in the bitstream.

[0166] Furthermore, in the embodiments of the present application, the grammar unit is comprised of one or more data units in the bitstream described below: a data unit containing the current block, a slice header information data unit, an image header information data unit, an image layer parameter set, a sequence parameter set, and an adaptive parameter set.

[0167] Furthermore, in the embodiment of the present application, the decoding unit 401 is specifically configured to analyze the bitstream to obtain the MIP mode index number of the current block, determine the size type of the current block, and determine the MIP mode indicated by the MIP mode index number from a list of candidate MIP modes corresponding to the size type as the MIP mode of the current block.

[0168] Furthermore, in the embodiments of the present application, if the current block size type is of type 1, the candidate MIP mode list is constructed based on 16 types of MIP modes; if the current block size type is of type 2, the candidate MIP mode list is constructed based on 8 types of MIP modes; and if the current block size type is of type 3, the candidate MIP mode list is constructed based on 6 types of MIP modes.

[0169] Furthermore, in the embodiments of the present application, the decoding unit 401 is configured to set the size type of the current block as the first type when the width and height of the current block are both equal to 4, to set the size type of the current block as the second type when the width and height of the current block are both equal to 8, or the width of the current block is equal to 8 and the height is equal to 4, or the width of the current block is equal to 4 and the height is equal to 8, and to set the size type of the current block as the third type when the width and height of the current block do not satisfy the above conditions.

[0170] Furthermore, in the embodiment of the present application, the decoding unit 401 is configured to set the size type of the current block as the first type when both the width and height of the current block are equal to 4, to set the size type of the current block as the second type when both the width and height of the current block are equal to 8, or when one of the width and height of the current block is equal to 4, and to set the size type of the current block as the third type when the width and height of the current block do not satisfy the above conditions.

[0171] Figure 12 is a schematic diagram of the configuration of a decoder according to an embodiment of the present invention. As shown in Figure 12, the decoder 400 according to an embodiment of the present invention may further include a second processor 403, a second memory 404 in which executable instructions of the second processor 403 are stored, a second communication interface 405, and a second bus 406 for connecting the second processor 403, the second memory 404, and the second communication interface 405.

[0172] Furthermore, in the embodiments of the present application, the second processor 403 is used to analyze the bitstream and determine the MIP mode parameter of the current block, and if the value of the MIP mode parameter indicates that the current block uses the MIP mode to determine the intra-predicted value of the current block, to analyze the bitstream and determine the MIP mode of the current block and determine the predicted values ​​of the luminance component and chromaticity component corresponding to the current block based on the MIP mode, and to decode the current block based on the predicted values.

[0173] Furthermore, in this embodiment, each functional module may be integrated into a single processing unit, each unit may exist physically independently, and two or more units may be integrated into a single unit. The integrated unit may be implemented in hardware form or in the form of a software functional module.

[0174] The integrated unit may be implemented in the form of a software function module and, when sold or used as an independent product, may be stored on a single computer-readable storage medium. Based on this understanding, the essential or prior art contribution of the proposed technology of this embodiment, or all or part of the proposed technology, may be embodied in the form of a software product. The computer software product is stored on a single storage medium containing some instructions for causing a computer device (which may be a personal computer, server, or network device, etc.) or processor to perform all or part of the steps of the method of this embodiment. The storage medium may include various media capable of storing program code, such as USB memory, portable hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0175] Embodiments of the present invention provide an image decoder that analyzes a bitstream to determine the MIP mode parameter of the current block, and if the value of the MIP mode parameter indicates that the current block will use MIP mode to determine the intra-predicted value of the current block, analyzes the bitstream to determine the MIP mode of the current block, and determines the predicted values ​​of the luminance and chromaticity components corresponding to the current block based on the MIP mode, and decodes the current block based on the predicted values. That is, in embodiments of the present invention, when an encoder performs intra-prediction on the current block, if it decides that the current block will use MIP mode, it can obtain the intra-predicted value of the current block using MIP mode, set the MIP mode parameter, write it to the bitstream, and transmit it to the decoder, and the decoder can analyze the bitstream to obtain the MIP mode parameter, and if the MIP mode parameter indicates that the current block will use MIP mode, the decoder can determine the intra-predicted value of the current block using MIP mode. As can be seen from the above, the image prediction method according to the present invention can use a grammar unit to indicate whether the current block in the bitstream is using MIP mode, thereby simplifying the image prediction process, reducing complexity in ensuring encoding / decoding performance, decreasing the memory space and overall time required for the encoding / decoding process, and effectively improving encoding / decoding efficiency.

[0176] Embodiments of the present application provide a computer-readable storage medium and a computer-readable storage medium that, when a program is stored in it and the program is executed by a processor, realize the method described in the above embodiment.

[0177] Specifically, the program instructions corresponding to the image prediction method of this embodiment may be stored on a storage medium such as an optical disc, hard disk, or USB memory, and when the program instructions corresponding to the image prediction method in the storage medium are read or executed by an electronic device, If the current block uses MIP mode to determine the intra-predicted value of the current block, the step of setting the value of the MIP mode parameter to indicate the use of MIP mode and writing it to the bitstream, The steps include determining the MIP mode of the current block and determining predicted values ​​for the luminance component and chromaticity component corresponding to the current block based on the MIP mode, The step includes writing the MIP mode of the current block to the bitstream.

[0178] Specifically, the program instructions corresponding to the image prediction method of this embodiment may be stored on a storage medium such as an optical disc, hard disk, or USB memory, and when the program instructions corresponding to the image prediction method in the storage medium are read or executed by an electronic device, The steps include: analyzing the bitstream to determine the MIP mode parameters of the current block, If the value of the MIP mode parameter indicates that the current block uses the MIP mode to determine the intra-predicted value of the current block, the bitstream is analyzed to determine the MIP mode of the current block, and based on the MIP mode, the predicted values ​​of the luminance component and chromaticity component corresponding to the current block are determined. The further step includes decoding the current block based on the predicted value.

[0179] As those skilled in the art will understand, embodiments of this application may be provided as methods, systems, or computer program products. Accordingly, this application may be provided in the form of hardware embodiments, software embodiments, or embodiments combining software and hardware. Furthermore, this application may be provided in the form of computer program products implemented on one or more computer-usable storage media (including, but not limited to, magnetic disk memory and optical memory) containing computer-usable program code.

[0180] This application has been described with reference to schematic implementation flowcharts and / or block diagrams of methods, apparatus (systems) and computer program products relating to embodiments of this application. As can be understood, each process and / or block in the schematic implementation flowchart and / or block diagram, and combinations of processes and / or blocks in the schematic implementation flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a dedicated computer, an embedded processor or other programmable data processing device to generate a machine, thereby generating an apparatus for implementing one or more processes in the schematic implementation flowchart and / or one or more blocks in the block diagram, based on instructions executed by the processor of the computer or other programmable data processing device.

[0181] These computer program instructions may be stored in computer-readable memory that can guide a computer or other programmable data processing device to operate in a particular manner, thereby causing the instructions stored in the computer-readable memory to generate a product equipped with an instruction device. The instruction device implements a function specified in one or more processes in a schematic implementation flowchart and / or one or more blocks in a block diagram.

[0182] These computer program instructions may be further installed in a computer or other programmable data processing device. This generates the processing realized by the computer by executing a series of operational steps in the computer or other programmable device. Thus, the instructions executed in the computer or other programmable device provide steps to realize a specified function in one or more processes in a schematic implementation flowchart and / or one or more blocks in a block diagram.

[0183] The above description is merely a preferred embodiment of the present application and is not intended to limit the scope of protection of the present application. [Industrial applicability]

[0184] Embodiments of the present invention provide an image prediction method, an encoder, a decoder, and a storage medium. When the current block uses MIP mode to determine its intra-predicted value, the encoder sets the value of the MIP mode parameter to indicate the use of MIP mode and writes it to the bitstream, determines the MIP mode of the current block, determines the predicted values ​​of the luminance and chromaticity components corresponding to the current block based on the MIP mode, and writes the MIP mode of the current block to the bitstream. The decoder analyzes the bitstream to determine the MIP mode parameter of the current block, and when the value of the MIP mode parameter indicates that the current block uses MIP mode to determine its intra-predicted value, it analyzes the bitstream to determine the MIP mode of the current block, determines the predicted values ​​of the luminance and chromaticity components corresponding to the current block based on the MIP mode, and decodes the current block based on the predicted values. In other words, in the embodiment of the present invention, when the encoder performs intraprediction on the current block, if it decides that the current block will use MIP mode, it can obtain the intrapredicted value of the current block using MIP mode, set the MIP mode parameters, write them to the bitstream, and transmit them to the decoding side. The decoder analyzes the bitstream to obtain the MIP mode parameters, and if the MIP mode parameters indicate that the current block will use MIP mode, the decoder can determine the intrapredicted value of the current block using MIP mode. As can be seen from the above, the image prediction method according to the present invention can use a grammar unit to indicate in the bitstream whether the current block will use MIP mode, thereby simplifying the image prediction process, reducing complexity in ensuring encoding / decoding performance, decreasing the memory space and overall time required for the encoding / decoding process, and effectively improving encoding / decoding efficiency.

Claims

1. An image prediction method applied to a decoder, Analyze the bitstream to determine the MIP mode parameters of the current block, If the value of the MIP mode parameter indicates that the MIP mode is used to determine the intra-predicted value of the current block for the current block, then the MIP mode of the current block is determined, and the predicted value corresponding to the current block is determined based on the MIP mode, Determining the MIP mode of the current block is: The current block size type is determined, This includes determining the MIP mode of the current block, indicated by the MIP mode index, from a list of candidate MIP modes corresponding to the size type, as the MIP mode of the current block. The MIP mode parameters are represented by a first grammar unit, which is included in the data unit corresponding to the current block. The MIP mode index is indicated by a second grammar unit, which is included in the data unit corresponding to the current block. If the current block size type is type 1, the candidate MIP mode list includes 16 types of MIP modes. If the current block size type is type 2, the candidate MIP mode list includes eight types of MIP modes. If the current block size type is the third type, the candidate MIP mode list includes six types of MIP modes. Image prediction method.

2. The aforementioned image prediction method further, The image prediction method according to claim 1, which includes deciding not to use the MIP mode for the current block if the value of the MIP mode parameter indicates that the MIP mode will not be used to determine the intra-predicted value of the current block for the current block.

3. Determining the size type of the current block is, If the width and height of the current block are both equal to 4, the size type of the current block is set to the first type, If the width and height of the current block are both equal to 8, or if one of the width and height of the current block is equal to 4, the size type of the current block is set to the second type. The image prediction method according to claim 2, further comprising setting the size type of the current block to the third type if the width and height of the current block do not satisfy the above conditions.

4. An image prediction method applied to an encoder, When determining the intra-predicted value of the current block using MIP mode for the current block, the value of the MIP mode parameter is set to indicate that MIP mode should be used. The process includes determining the MIP mode of the current block, determining the MIP mode index of the current block based on the MIP mode, and writing it to the bitstream. Determining the MIP mode of the current block is: The current block size type is determined, A candidate MIP mode list is constructed based on the size type, wherein the MIP mode index and the candidate MIP mode are associated in the candidate MIP mode list. This includes determining the MIP mode of the current block from the candidate MIP mode list, The MIP mode parameters are represented by a first grammar unit, which is included in the data unit corresponding to the current block. The MIP mode index is indicated by a second grammar unit, which is included in the data unit corresponding to the current block. If the current block size type is type 1, the candidate MIP mode list includes 16 types of MIP modes. If the current block size type is type 2, the candidate MIP mode list includes eight types of MIP modes. If the current block size type is the third type, the candidate MIP mode list includes six types of MIP modes. Image prediction method.

5. The aforementioned image prediction method further, If the MIP mode is not used to determine the intra-predicted value of the current block, the value of the MIP mode parameter is set to indicate that the MIP mode is not used and written to the bitstream. The image prediction method according to claim 4.

6. Determining the size type of the current block is, If the width and height of the current block are both equal to 4, the size type of the current block is set to the first type, If the width and height of the current block are both equal to 8, or if one of the width and height of the current block is equal to 4, the size type of the current block is set to the second type. If the width and height of the current block do not satisfy the above conditions, the size type of the current block is set to the third type, including The image prediction method according to claim 5.

7. It is a decoder, A decoder comprising a processor and a memory storing instructions that can be executed by the processor, wherein when the instructions are executed by the processor, the processor performs the image prediction method according to any one of claims 1 to 3.

8. It is an encoder, An encoder comprising a processor and a memory storing instructions that can be executed by the processor, wherein when the instructions are executed by the processor, the processor performs the image prediction method according to any one of claims 4 to 6.

9. A non-volatile computer-readable medium comprising a program and a bitstream, wherein the program causes a processor to execute the image prediction method described in any one of claims 4 to 6 to generate the bitstream.

Images