Calculating sample distances for geometric partitioning modes

Abstract

To provide an apparatus and method for coding and decoding.SOLUTION: A method of coding implemented by a decoding device or an encoding device includes the steps of: obtaining the value of an angle parameter for a current block; obtaining the value of the width of the current block and the value of the height of the current block; calculating a comparison value between the value of the width and the value of the height; obtaining a first value according to the value of the angle parameter and the comparison value; calculating a sample distance value for a sample in the current block according to the first value; and obtaining a prediction value for the sample in the current block according to the sample distance value.SELECTED DRAWING: Figure 20

Description

[Technical Field]

[0001] FIELD Embodiments of the present application (disclosure) relate generally to the field of picture processing, and in particular to prediction for partitioning, and more particularly to calculating sample distances for geometric partitioning modes. [Background technology]

[0002] Video coding (video encoding and decoding) is used in a wide range of digital video applications, such as broadcast digital TV, video transmission over the Internet and mobile networks, real-time conversation applications such as video chat, video conferencing, DVD and Blu-ray discs, video content acquisition and editing systems, and camcorders in security applications.

[0003] The amount of video data required to render even a relatively short video can be significant, which can pose challenges when the data is to be streamed or otherwise transmitted over communication networks with limited bandwidth capacity. Therefore, video data is generally compressed before being transmitted over modern communication networks. Because memory resources may be limited, video size can also be an issue when the video is stored on a storage device. Often, video compression devices use software and / or hardware at the source to code the video data before transmission or storage, thereby reducing the amount of data needed to represent a digital video image. The compressed data is then received at the destination by a video decompression device, which decodes the video data. With limited network resources and an ever-increasing demand for higher video quality, improved compression and decompression techniques that increase compression ratios with little or no sacrifice in picture quality are desirable. Summary of the Invention [Means for solving the problem]

[0004] Embodiments of the present application provide apparatuses and methods for encoding and decoding according to the independent claims.

[0005] These and other objects are achieved by the subject matter of the independent claims. Further implementation forms are evident from the dependent claims, the description and the drawings.

[0006] A first aspect of the present invention provides a coding method to be implemented by a decoding device or an encoding device, the method comprising the steps of obtaining an angle parameter value for a current block, obtaining a width value of the current block and a height value of the current block, calculating a ratio value between the width value and the height value, calculating sample distance values ​​for samples of the current block according to the angle parameter value and the ratio value, and obtaining predicted values ​​for samples of the current block according to the sample distance values.

[0007] In the present embodiment, the angular parameter and the angular parameter are synonymous.

[0008] According to an embodiment of the present invention, a ratio value between a block width value and a block height value is calculated. This ratio value is used to calculate a sample distance value, and the prediction value is calculated more accurately. Therefore, the prediction residual may be reduced, and the coding efficiency can be improved.

[0009] In one implementation, the step of calculating the distance value of the sample relative to the sample of the current block according to the value of the angle parameter and the value of the ratio includes: Obtaining a first value according to the value of the angle parameter and the value of the ratio; calculating a distance value of the sample for the sample of the current block according to the first value.

[0010] In one implementation, the step of calculating the distance value of the sample relative to the sample of the current block according to the first value includes: Calculating a distance value of the sample for the current block of samples according to the first value and the value of the angle parameter.

[0011] In one implementation, the step of calculating the distance value of the sample relative to the sample of the current block according to the first value includes: The method includes calculating a distance value of a sample for a sample of the current block according to the first value, the value of the angle parameter, the value of a distance index (e.g., the distance index of the current block), the width value, and the height value.

[0012] In one implementation, the distance value of a sample represents the horizontal or vertical or combined vertical and horizontal distance of the sample to a dividing line, which is used to divide the coding block into two sub-blocks.

[0013] In one implementation, the step of obtaining a prediction value for the sample of the current block according to the distance value of the sample includes: calculating two weighting factors according to the distance values ​​of the samples; and obtaining a predicted value for the sample of the current block according to the first predicted value, the second predicted value, and the two weighting factors, for example, by "applying the two weighting factors to the first predicted value and the second predicted value" or "applying the first weighting factor to the first predicted value and the second weighting factor to the second predicted value."

[0014] In one implementation, the ratio value is: whRatio = (W >= H) ? W / H : H / W where whRatio is the ratio value, W is the width value, and H is the height value.

[0015] In one implementation, the value of the angle parameter is an integer value, and the numerical range of the value of the angle parameter is from 0 to 31, inclusive.

[0016] In one implementation, the ratio value is: whRatio = (wIdx >= hIdx) ? wIdx - hIdx : hIdx - wIdx where whRatio is the ratio value, W is the width value, H is the height value, the value of wIdx is equal to log2(W) - 3, and the value of hIdx is equal to log2(H) - 3.

[0017] In one implementation, the sample distance value is sample_dist = ((2*x) - W + K)*f1(alpha) + ((2*y) - H + K))*f2(alpha) - distanceIdx*stepD*scaleStep where sample_dist is the sample distance value, f1() and f2() are functions, alpha is the angle parameter value, stepD is the first value, the scaleStep value is equal to either the width or height value, x and y are the coordinates of the sample relative to the top-left sample of the current block, and K is an integer offset value.

[0018] In one implementation, the sample distance value is sample_dist = ((2*x) - W + K)*f(dispIdxN) + ((2*y) - H + K))*f(dispIdxS) - distanceIdx*stepD*scaleStep where sample_dist is the distance value of the sample, f() is a function, dispIdxN or dispIdxS is the index value, stepD is the first value, the scaleStep value is equal to either the width or height value, x and y are the coordinates of the sample relative to the top-left sample of the current block, and K is an integer offset value.

[0019] A second aspect of the present invention provides a video coding or decoding apparatus, the apparatus including: a parameter acquisition module configured to acquire a value of an angle parameter for a current block, the parameter acquisition module being further configured to acquire a width value of the current block and a height value of the current block; a ratio calculation module configured to calculate a ratio value between the width value and the height value; a sample distance calculation module configured to calculate sample distance values ​​for samples of the current block according to the value of the angle parameter and the ratio value; and a prediction module configured to acquire predicted values ​​for samples of the current block according to the sample distance values.

[0020] The method according to the first aspect of the present invention may be performed by an apparatus according to the second aspect of the present invention. Further features and modes of implementation of the above method correspond to the features and modes of implementation of the apparatus according to the second aspect of the present invention.

[0021] In an embodiment, a decoder (30) or encoder (20) is disclosed that includes processing circuitry for performing a method according to any one of the above embodiments and implementations.

[0022] In an embodiment, a computer program product is disclosed that includes program code for performing a method according to any one of the above embodiments and implementations.

[0023] In an embodiment, one or more processors; A decoder or encoder is provided that includes: a non-transitory computer-readable storage medium coupled to a processor and storing programming for execution by the processor, the programming, when executed by the processor, configuring the decoder or encoder to perform a method according to any one of the above embodiments and implementations.

[0024] In an embodiment, a non-transitory storage medium is provided that contains an encoded bitstream that is decoded by an image decoding device, the bitstream being generated by dividing a frame of a video signal or image signal into a plurality of blocks and containing a plurality of syntax elements, the plurality of syntax elements containing an indicator (syntax) according to any one of the above embodiments and implementations.

[0025] The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will become apparent from the description, drawings, and claims.

[0026] In the following, embodiments of the invention will be explained in more detail with reference to the accompanying figures and drawings. [Brief explanation of the drawings]

[0027] [Figure 1A] 1 is a block diagram illustrating an example of a video coding system configured to implement embodiments of the present invention. [Figure 1B] FIG. 2 is a block diagram illustrating another example of a video coding system configured to implement embodiments of the present invention. [Figure 2] 1 is a block diagram illustrating an example of a video encoder configured to implement embodiments of the present invention. [Figure 3] 1 is a block diagram illustrating an exemplary structure of a video decoder configured to implement embodiments of the present invention. [Figure 4]FIG. 1 is a block diagram illustrating an example of an encoding device or a decoding device. [Figure 5] FIG. 10 is a block diagram showing another example of an encoding device or a decoding device. [Figure 6a] FIG. 10 illustrates an example of co-located blocks. [Figure 6b] FIG. 1 illustrates an example of spatially neighboring blocks. [Figure 7] FIG. 10 is a diagram illustrating some examples of triangular prediction modes. [Figure 8] FIG. 10 is a diagram illustrating some examples of lower-order block prediction modes. [Figure 9] FIG. 10 is a diagram illustrating an example of block division. [Figure 10] FIG. 10 is a diagram illustrating an example of block division. [Figure 11] FIG. 10 is a diagram illustrating an example of block division. [Figure 12] FIG. 10 is a diagram illustrating an example of block division. [Figure 13] FIG. 10 illustrates an exemplary implementation of a predefined lookup table for stepD. [Figure 14] FIG. 1 illustrates an exemplary implementation of a predefined lookup table for f(). [Figure 15] FIG. 10 illustrates an example of a quantization aspect associated with a predefined lookup table for stepD. [Figure 16] FIG. 10 illustrates an example of a quantization scheme in which a maximum distance ρ max is defined for a given coding block. [Figure 17] FIG. 10 illustrates an example of a quantization scheme in which an alternative maximum distance ρ max is defined for a given coding block. [Figure 18] 1 is a block diagram illustrating an exemplary structure of a content supply system for implementing a content distribution service. [Figure 19] FIG. 2 is a block diagram illustrating the structure of an example terminal device. [Figure 20] 1 is a flow chart illustrating an embodiment of a method according to the present invention. [Figure 21] 1 is a block diagram illustrating an embodiment of an apparatus according to the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0028] In the following, the same reference signs, unless otherwise specified, refer to identical or at least functionally equivalent features.

[0029] In the following description, reference is made to the accompanying drawings which form a part of this disclosure and which show, by way of illustration, specific aspects of embodiments of the invention or in which embodiments of the invention may be practiced. It is understood that embodiments of the invention may be practiced in other ways and may include structural or logical changes not shown in the drawings. Therefore, the following detailed description is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.

[0030] For example, it is understood that disclosure related to a described method may also apply to a corresponding device or system configured to perform the method, and vice versa. For example, when one or more particular method steps are described, the corresponding device may include one or more units, e.g., functional units, for performing the described one or more method steps (e.g., one unit that performs one or more steps, or multiple units that each perform one or more of the steps), even if such one or more units are not explicitly described or shown in a figure. On the other hand, for example, when a particular apparatus is described based on one or more units, e.g., functional units, the corresponding method may include one step for performing the function of the one or more units (e.g., one step that performs the function of one or more units, or multiple steps that each perform one or more functions of one or more units), even if such one or more steps are not explicitly described or shown in a figure. Furthermore, it is understood that features of various exemplary embodiments and / or aspects described herein may be combined with each other unless expressly stated otherwise.

[0031] Video coding generally refers to the processing of a sequence of pictures that form a video or a video sequence. Instead of the term "picture," the terms "frame" or "image" may be used synonymously in the field of video coding. Video coding (or coding in general) includes two parts: video encoding and video decoding. Video encoding is performed at the source side and generally involves processing the original video picture (e.g., by compression) to reduce the amount of data needed to represent the video picture (for more efficient storage and / or transmission). Video decoding is performed at the destination side and generally involves the reverse processing compared to the encoder to reconstruct the video picture. Embodiments that refer to "coding" a video picture (or pictures in general) are understood to relate to "encoding" or "decoding" the video picture or the respective video sequence. The combination of the encoding and decoding parts is also called a codec (coding and decoding).

[0032] In the case of lossless video coding, the original video picture can be reconstructed (assuming there is no transmission loss or other data loss during storage or transmission), i.e., the reconstructed video picture has the same quality as the original video picture. In the case of lossy video coding, further compression, for example by quantization, is performed to reduce the amount of data representing the video picture, which cannot be perfectly reconstructed at the decoder, i.e., the quality of the reconstructed video picture is lower or worse than the quality of the original video picture.

[0033] Some video coding standards belong to the group of "lossy hybrid video codecs" (i.e., combine spatial and temporal prediction in the sample domain with 2D transform coding for applying quantization in the transform domain). Each picture of a video sequence is generally partitioned into a set of non-overlapping blocks, and coding is generally performed at the block level. In other words, at an encoder, video is generally processed, i.e., encoded, at the block (video block) level, for example, by generating a prediction block using spatial (intra-picture) prediction and / or temporal (inter-picture) prediction, subtracting the prediction block from a current block (the block currently being / to be processed) to obtain a residual block, transforming the residual block, and quantizing the residual block in the transform domain to reduce the amount of data to be transmitted (compression); whereas at a decoder, an inverse process is applied to the coded or compressed block compared to the encoder to reconstruct the current block for representation. Furthermore, the encoder replicates the decoder's processing loop so that both generate the same prediction (eg, intra and inter prediction) and / or reconstruction for processing, i.e., coding, subsequent blocks.

[0034] In the following, embodiments of a video coding system 10, a video encoder 20 and a video decoder 30 are described based on FIGS.

[0035] 1A is a schematic block diagram illustrating an example coding system 10, e.g., video coding system 10 (or coding system 10 for short), that may utilize techniques of the present application. A video encoder 20 (or encoder 20 for short) and a video decoder 30 (or decoder 30 for short) of video coding system 10 illustrate examples of devices that may be configured to perform techniques according to various examples described in the present application.

[0036] As shown in FIG. 1A, coding system 10 includes a source device 12 configured to provide encoded picture data 21 to, for example, a destination device 14 for decoding the encoded picture data 13.

[0037] The source device 12 includes an encoder 20 and may additionally, i.e., optionally, include a picture source 16, a preprocessor (or preprocessing unit) 18, e.g., a picture preprocessor 18, and a communication interface or unit 22.

[0038] Picture source 16 may include or be any kind of picture capture device, e.g., a camera for capturing real-world pictures, and / or any kind of picture generation device, e.g., a computer graphics processor for generating computer-animated pictures, or any kind of other device for acquiring and / or providing real-world pictures, computer-generated pictures (e.g., screen content, virtual reality (VR) pictures), and / or any combination thereof (e.g., augmented reality (AR) pictures). Picture source may also be any kind of memory or storage for storing any of the above-mentioned pictures.

[0039] To distinguish from the preprocessor 18 and the processing performed by the preprocessing unit 18, the picture or picture data 17 may also be referred to as a raw picture or raw picture data 17.

[0040] The pre-processor 18 is configured to receive (raw) picture data 17 and perform pre-processing on the picture data 17 to obtain a pre-processed picture 19 or pre-processed picture data 19. The pre-processing performed by the pre-processor 18 may include, for example, cropping, color format conversion (e.g., from RGB to YCbCr), color correction, or noise removal. It may be understood that the pre-processing unit 18 may be an optional component.

[0041] Video encoder 20 is configured to receive pre-processed picture data 19 and provide encoded picture data 21 (further details are described below, eg, with reference to FIG. 2).

[0042] The communication interface 22 of the source device 12 may be configured to receive the encoded picture data 21 and transmit the encoded picture data 21 (or any further processed version thereof) via the communication channel 13 to another device, e.g., the destination device 14 or any other device, for storage or direct reconstruction.

[0043] The destination device 14 includes a decoder 30 (e.g., a video decoder 30) and may additionally, i.e., optionally, include a communication interface or communication unit 28, a post-processor 32 (or post-processing unit 32), and a display device 34.

[0044] The communications interface 28 of the destination device 14 is configured to receive the encoded picture data 21 (or any further processed version thereof), for example directly from the source device 12 or from any other source, for example a storage device, for example a storage device for encoded picture data, and to provide the encoded picture data 21 to the decoder 30.

[0045] The communication interface 22 and the communication interface 28 may be configured to transmit or receive the encoded picture data 21 or the encoded data 13 via a direct communication link between the source device 12 and the destination device 14, e.g., a direct wired or wireless connection, or via any type of network, e.g., a wired or wireless network or any combination thereof, or any type of private and public network, or any type of combination thereof.

[0046] The communications interface 22 may be configured to process the encoded picture data 21 using any type of transmission encoding or processing, for example packaging the encoded picture data 21 into a suitable format, for example packets, and / or for transmission over a communications link or network.

[0047] The communications interface 28 forming the counterpart of the communications interface 22 may for example be configured to receive the transmitted data and process the transmitted data using any kind of corresponding transmission decoding or processing and / or depackaging to obtain the encoded picture data 21.

[0048] Both communication interface 22 and communication interface 28 may be configured as unidirectional communication interfaces, as indicated by the arrows for communication channel 13 in FIG. 1A pointing from source device 12 toward destination device 14, or as bidirectional communication interfaces, and may be configured, for example, to send and receive messages, for example, to set up a connection and to acknowledge and exchange any other information related to the communication link and / or data transmission, e.g., the transmission of encoded picture data.

[0049] The decoder 30 is configured to receive encoded picture data 21 and provide decoded picture data 31 or decoded pictures 31 (further details are described below, for example, based on Figure 3 or Figure 5).

[0050] Post-processor 32 of destination device 14 is configured to post-process decoded picture data 31 (also referred to as reconstructed picture data), e.g., decoded picture 31, to obtain post-processed picture data 33, e.g., post-processed picture 33. The post-processing performed by post-processing unit 32 may include, e.g., color format conversion (e.g., from YCbCr to RGB), color correction, cropping, or resampling, or any other processing to prepare, e.g., decoded picture data 31, for display by, e.g., display device 34.

[0051] Display device 34 of destination device 14 is configured to receive post-processed picture data 33, for example, to display the picture to a user or viewer. Display device 34 may be or include any type of display for showing the reconstructed picture, e.g., an integrated or external display or monitor. The display may include, for example, a liquid crystal display (LCD), an organic light emitting diode (OLED) display, a plasma display, a projector, a microLED display, a liquid crystal on silicon (LCoS), a digital light processor (DLP), or any other type of display.

[0052] 1A depicts source device 12 and destination device 14 as separate devices, embodiments of the devices may also include both or both functionality, source device 12 or corresponding functionality and destination device 14 or corresponding functionality. In such embodiments, source device 12 or corresponding functionality and destination device 14 or corresponding functionality may be implemented using the same hardware and / or software or by separate hardware and / or software or any combination thereof.

[0053] As will be apparent to those skilled in the art based on the description, the functions of different units or the presence and (exact) division of functions within source device 12 and / or destination device 14 shown in FIG. 1A may vary depending on the actual device and application.

[0054] Encoder 20 (e.g., video encoder 20) or decoder 30 (e.g., video decoder 30), or both encoder 20 and decoder 30, may be implemented by processing circuitry shown in FIG. 1B, such as one or more microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), discrete logic, hardware, dedicated to video coding, or any combination thereof. Encoder 20 may be implemented by processing circuitry 46 to embody various modules discussed in connection with encoder 20 of FIG. 2 and / or any other encoder system or subsystem described herein. Decoder 30 may be implemented by processing circuitry 46 to embody various modules discussed in connection with decoder 30 of FIG. 3 and / or any other decoder system or subsystem described herein. The processing circuitry may be configured to perform various operations discussed later. If the techniques are implemented partially in software, as shown in FIG. 5, a device may store instructions for the software on a suitable non-transitory computer-readable storage medium and execute the instructions in hardware using one or more processors to perform the techniques of this disclosure. Either video encoder 20 and video decoder 30 may be incorporated as part of a combined encoder / decoder (codec) within a single device, for example, as shown in FIG. 1B.

[0055] Source device 12 and destination device 14 may include any of a wide range of devices, including any type of handheld or fixed device, e.g., a notebook or laptop computer, a mobile phone, a smartphone, a tablet or tablet computer, a camera, a desktop computer, a set-top box, a television, a display device, a digital media player, a video game console, a video streaming device (such as a content service server or content distribution server), a broadcast receiver device, a broadcast transmitter device, etc., and may use no operating system or any type of operating system. In some cases, source device 12 and destination device 14 may be capable of wireless communication. Thus, source device 12 and destination device 14 may be wireless communication devices.

[0056] In some cases, the video coding system 10 shown in FIG. 1A is merely an example, and the techniques of this disclosure may be applied to video coding situations (e.g., video encoding or video decoding) that do not necessarily involve any data communication between an encoding device and a decoding device. In other examples, data may be retrieved from local memory, streamed over a network, etc. A video encoding device may encode data and store it in memory, and / or a video decoding device may retrieve data from memory and decode it. In some examples, encoding and decoding are performed by devices that do not communicate with each other but simply encode data to memory and / or retrieve data from memory and decode it.

[0057] For ease of explanation, embodiments of the present invention are described herein with reference to reference software, e.g., High-Efficiency Video Coding (HEVC), or Versatile Video Coding (VVC), the next-generation video coding standard developed by the ITU-T Video Coding Experts Group (VCEG) and the ISO / IEC Joint Collaboration Team on Video Coding (JCT-VC) of the Motion Picture Experts Group (MPEG). Those skilled in the art will understand that embodiments of the present invention are not limited to HEVC or VVC.

[0058] Encoder and encoding method FIG. 2 shows a schematic block diagram of an exemplary video encoder 20 configured to implement the techniques of the present application. In the example of FIG. 2, the video encoder 20 includes an input 201 (or input interface 201), a residual calculation unit 204, a transform processing unit 206, a quantization unit 208, an inverse quantization unit 210, an inverse transform processing unit 212, a reconstruction unit 214, a loop filter unit 220, a decoded picture buffer (DPB) 230, a mode selection unit 260, an entropy coding unit 270, and an output 272 (or output interface 272). The mode selection unit 260 may include an inter prediction unit 244, an intra prediction unit 254, and a partitioning unit 262. The inter prediction unit 244 may include a motion estimation unit and a motion compensation unit (not shown). The video encoder 20 shown in FIG. 2 may also be referred to as a hybrid video encoder or a video encoder using a hybrid video codec.

[0059] The residual calculation unit 204, the transform processing unit 206, the quantization unit 208, and the mode selection unit 260 may be considered to form a forward signal path of the encoder 20, while the inverse quantization unit 210, the inverse transform processing unit 212, the reconstruction unit 214, the buffer 216, the loop filter 220, the decoded picture buffer (DPB) 230, the inter prediction unit 244, and the intra prediction unit 254 may be considered to form a backward signal path of the video encoder 20, which corresponds to the signal path of a decoder (see video decoder 30 in FIG. 3 ). The inverse quantization unit 210, the inverse transform processing unit 212, the reconstruction unit 214, the loop filter 220, the decoded picture buffer (DPB) 230, the inter prediction unit 244, and the intra prediction unit 254 are also considered to form a “built-in decoder” of the video encoder 20.

[0060] Picture & Picture Division (Picture & Block) Encoder 20 may, for example, be configured to receive via input 201 picture 17 (or picture data 17), e.g., a picture of a sequence of pictures forming a video or a video sequence. The received picture or picture data may further be preprocessed picture 19 (or preprocessed picture data 19). For simplicity, the following description refers to picture 17. Picture 17 may also be called a current picture or a picture to be coded (particularly in video coding, to distinguish the current picture from other pictures, e.g., already coded and / or decoded pictures of the same video sequence, i.e., the video sequence that also includes the current picture).

[0061] A (digital) picture is or can be considered as a two-dimensional array or matrix of samples having intensity values. The samples of the array may also be called pixels (short for picture element) or pels. The number of samples in the horizontal and vertical directions (or axes) of the array or picture defines the size and / or resolution of the picture. For color representation, three color components are generally used, i.e., a picture may be represented or include three sample arrays. In an RBG format or color space, a picture includes corresponding red, green, and blue sample arrays. However, in video coding, each pixel is generally represented in a luminance and chrominance format or color space, e.g., YCbCr, which includes a luminance component denoted by Y (although L may be used instead) and two chrominance components denoted by Cb and Cr. The luminance (or luma for short) component Y represents brightness or gray level intensity (e.g., similar to a grayscale picture), while the two chrominance (or chroma for short) components Cb and Cr represent chromaticity or color information components. Thus, a picture in YCbCr format includes a luminance sample array of luminance sample values ​​(Y) and two chrominance sample arrays of chrominance values ​​(Cb and Cr). A picture in RGB format may be converted or transformed to YCbCr format or vice versa, a process also known as color transformation or conversion. If a picture is monochrome, the picture may include only a luminance sample array. Thus, a picture may be, for example, an array of luma samples in a monochrome format, or an array of luma samples and two corresponding arrays of chroma samples in 4:2:0, 4:2:2, and 4:4:4 color formats.

[0062] Embodiments of video encoder 20 may include a picture partitioning unit (not shown in FIG. 2) configured to partition picture 17 into multiple (usually non-overlapping) picture blocks 203. These blocks may also be called root blocks, macroblocks (H.264 / AVC), or coding tree blocks (CTBs) or coding tree units (CTUs) (H.265 / HEVC and VVC). The picture partitioning unit may be configured to use the same block size for all pictures of a video sequence and a corresponding grid defining the block size, or to vary the block size among pictures or subsets or groups of pictures, and to partition each picture into corresponding blocks.

[0063] In further embodiments, the video encoder may be configured to directly receive blocks 203 of picture 17, e.g., one, some, or all of the blocks that form picture 17. Picture blocks 203 may also be referred to as current picture blocks or picture blocks to be coded.

[0064] Similar to picture 17, picture block 203, although smaller in dimensions than picture 17, is or can still be considered as a two-dimensional array or matrix of samples having intensity values ​​(sample values). In other words, block 203 may include, for example, one sample array (e.g., a luma array for a monochrome picture 17, or a luma or chroma array for a color picture), or three sample arrays (e.g., a luma and two chroma arrays for a color picture 17), or any other number and / or type of array, depending on the applied color format. The number of samples in the horizontal and vertical directions (or axes) of block 203 defines the size of block 203. Thus, a block may be, for example, an MxN (M columns by N rows) array of samples or an MxN array of transform coefficients.

[0065] The embodiment of video encoder 20 shown in FIG. 2 may be configured to encode picture 17 block by block, eg, encoding and prediction is performed for each block 203.

[0066] Calculating residuals The residual calculation unit 204 may be configured to calculate the residual block 205 (also referred to as the residual 205) based on the picture block 203 and the predictive block 265 (further details about the predictive block 265 are provided later), for example, by subtracting the sample values ​​of the predictive block 265 from the sample values ​​of the picture block 203 on a sample-by-sample (pixel-by-pixel) basis to obtain the residual block 205 in the sample domain.

[0067] conversion The transform processing unit 206 may be configured to apply a transform, for example, a discrete cosine transform (DCT) or a discrete sine transform (DST), to the sample values ​​of the residual block 205 to obtain transform coefficients 207 in a transform domain. The transform coefficients 207 may also be referred to as transform residual coefficients, and may represent the residual block 205 in the transform domain.

[0068] The transform processing unit 206 may be configured to apply an integer approximation of a DCT / DST, such as the transform specified for H.265 / HEVC. Compared to an orthogonal DCT transform, such an integer approximation is generally scaled by a particular factor. To maintain the norm of the residual blocks processed by the forward and inverse transforms, an additional scaling factor is applied as part of the transform process. The scaling factor is generally selected based on particular constraints, such as the scaling factor being a power of two for shift operations, the bit depth of the transform coefficients, a trade-off between accuracy and implementation cost, etc. For example, a particular scaling factor may be specified for the inverse transform, e.g., by the inverse transform processing unit 212 (and the corresponding inverse transform, e.g., by the inverse transform processing unit 312 in the video decoder 30), and a corresponding scaling factor for the forward transform, e.g., by the transform processing unit 206 of the encoder 20, may be specified accordingly.

[0069] An embodiment of video encoder 20 (respectively, transform processing unit 206) may be configured to output transform parameters, e.g., a certain transform or transforms, either as is or encoded or compressed by entropy coding unit 270, for example, so that video decoder 30 may receive the transform parameters and use them for decoding.

[0070] quantization The quantization unit 208 may be configured to quantize the transform coefficients 207, for example, by applying scalar quantization or vector quantization, to obtain quantized coefficients 209. The quantized coefficients 209 may also be referred to as quantized transform coefficients 209 or quantized residual coefficients 209.

[0071] The quantization process may reduce the bit depth associated with some or all of the transform coefficients 207. For example, an n-bit transform coefficient may be truncated to an m-bit transform coefficient during quantization, where n is greater than m. The degree of quantization may be modified by adjusting a quantization parameter (QP). For example, with respect to scalar quantization, different scaling may be applied to achieve finer or coarser quantization. A smaller quantization step size corresponds to finer quantization, while a larger quantization step size corresponds to coarser quantization. The applicable quantization step size may be indicated by the quantization parameter (QP). The quantization parameter may, for example, be an index into a predefined set of applicable quantization step sizes. For example, a small quantization parameter may correspond to fine quantization (small quantization step size) and a large quantization parameter may correspond to coarse quantization (large quantization step size), or vice versa. Quantization may include division by a quantization step size, and corresponding and / or inverse inverse quantization by, for example, the inverse quantization unit 210 may include multiplication by the quantization step size. Some standards, for example, HEVC, may be configured to determine the quantization step size using a quantization parameter. Generally, the quantization step size may be calculated based on the quantization parameter using a fixed-point approximation of an equation involving division. Additional scaling factors may be introduced for quantization and inverse quantization to restore the norm of the residual block, which may be modified due to scaling used in the fixed-point approximation of the equation for the quantization step size and the quantization parameter. In one exemplary implementation, the scaling of the inverse transform and inverse quantization may be combined. Alternatively, customized quantization tables may be used, e.g., signaled from the encoder to the decoder in the bitstream. Quantization is a lossy operation, and loss increases as the quantization step size increases.

[0072] Embodiments of video encoder 20 (respectively, quantization unit 208) may be configured to output a quantization parameter (QP), e.g., as is or to be encoded by entropy encoding unit 270, such that video decoder 30 may receive the quantization parameter and apply it for decoding.

[0073] inverse quantization Inverse quantization unit 210 is configured to apply the inverse quantization of quantization unit 208 to the quantized coefficients to obtain inverse quantized coefficients 211, e.g., by applying the inverse of the quantization scheme applied by quantization unit 208, based on or using the same quantization step size as quantization unit 208. The inverse quantized coefficients 211, also referred to as inverse quantized residual coefficients 211, may correspond to transform coefficients 207—although they are generally not identical to the transform coefficients due to loss due to quantization.

[0074] Inverse transformation The inverse transform processing unit 212 is configured to apply an inverse transform of the transform applied by the transform processing unit 206, for example, an inverse discrete cosine transform (DCT) or an inverse discrete sine transform (DST) or other inverse transform, to obtain a reconstructed residual block 213 (or corresponding dequantized coefficients 213) in the sample domain. The reconstructed residual block 213 may also be referred to as a transform block 213.

[0075] Rebuild The reconstruction unit 214 (e.g., an adder or summator 214) is configured to add the transform block 213 (i.e., the reconstructed residual block 213) to the prediction block 265, for example, by adding the sample values ​​of the reconstructed residual block 213 and the sample values ​​of the prediction block 265—sample by sample—to obtain a reconstructed block 215 in the sample domain.

[0076] filtering The loop filter unit 220 (or "loop filter" 220 for short) is configured to filter the reconstructed block 215 to obtain a filtered block 221, or generally, to filter reconstructed samples to obtain filtered samples. The loop filter unit is configured, for example, to smooth pixel transitions or otherwise improve video quality. The loop filter unit 220 may include one or more loop filters, such as a deblocking filter, a sample-adaptive offset (SAO) filter, or one or more other filters, for example, a bilateral filter, an adaptive loop filter (ALF), a sharpening filter, a smoothing filter, or a collaborative filter, or any combination thereof. Although the loop filter unit 220 is shown in FIG. 2 as being an in-loop filter, in other configurations, the loop filter unit 220 may be implemented as a post-loop filter. The filtered block 221 may also be referred to as a filtered reconstructed block 221.

[0077] Embodiments of video encoder 20 (respectively, loop filter unit 220) may be configured to output loop filter parameters (e.g., sample adaptive offset information) either as is or encoded by entropy coding unit 270, e.g., so that decoder 30 may receive and apply the same loop filter parameters or the respective loop filter for decoding.

[0078] Decoded Picture Buffer The decoded picture buffer (DPB) 230 may be a memory that stores reference pictures or generally reference picture data for encoding video data by the video encoder 20. The DPB 230 may be formed by any of a variety of memory devices, such as dynamic random access memory (DRAM), including synchronous DRAM (SDRAM), magnetoresistive RAM (MRAM), resistive RAM (RRAM), or other types of memory devices. The decoded picture buffer (DPB) 230 may be configured to store one or more filtered blocks 221. The decoded picture buffer 230 may further be configured to store other already-filtered blocks, e.g., already-reconstructed filtered blocks 221, of the same current picture or a different picture, e.g., an already-reconstructed picture, and / or may provide a complete already-reconstructed, i.e., decoded, picture (and corresponding reference blocks and samples) and / or a partially-reconstructed current picture (and corresponding reference blocks and samples), e.g., for inter-prediction. The decoded picture buffer (DPB) 230 may also be configured to store one or more unfiltered reconstructed blocks 215 or generally unfiltered reconstructed samples, for example, if the reconstructed blocks 215 are not filtered by the loop filter unit 220, or to store any other further processed version of the reconstructed blocks or samples.

[0079] Mode selection (classification & prediction) The mode select unit 260 includes a partitioning unit 262, an inter prediction unit 244, and an intra prediction unit 254, and is configured to receive or obtain original picture data, e.g., original block 203 (current block 203 of current picture 17), and reconstructed picture data, e.g., filtered and / or unfiltered reconstructed samples or blocks of the same (current) picture and / or from one or more already decoded pictures, for example, from the decoded picture buffer 230 or other buffer (e.g., a line buffer, not shown). The reconstructed picture data is used as reference picture data for prediction, e.g., inter prediction or intra prediction, to obtain a prediction block 265 or predictor 265.

[0080] The mode selection unit 260 may be configured to determine or select a partitioning and prediction mode (e.g., intra or inter prediction mode) for the prediction mode of the current block (which does not include partitioning) and generate a corresponding prediction block 265 used for calculating the residual block 205 and reconstructing the reconstructed block 215.

[0081] Embodiments of the mode selection unit 260 may be configured to select a partitioning and prediction mode (e.g., from partitioning and prediction modes supported by or available to the mode selection unit 260) that provides the best match, or in other words, the smallest residual (smallest residual means better compression for transmission or storage), or the smallest signaling overhead (smallest signaling overhead means better compression for transmission or storage), or that considers or balances both. The mode selection unit 260 may be configured to determine the partitioning and prediction mode based on rate-distortion optimization (RDO), i.e., to select the prediction mode that provides the smallest rate-distortion. Terms such as “best,” “minimum,” “optimum,” etc. in this context do not necessarily refer to the overall “best,” “minimum,” “optimum,” etc., but may also refer to satisfying termination or selection criteria such as values ​​above or below a threshold, or other constraints that potentially lead to a “suboptimal selection,” but that reduce complexity and processing time.

[0082] In other words, the partitioning unit 262 may be configured to partition the block 203 into smaller partitions or sub-blocks of the block (which also form blocks) using, for example, quadtree partitioning (QT), binary partitioning (BT), or ternary tree partitioning (TT), or any combination thereof, iteratively, and to perform prediction on, for example, each of the partitions or sub-blocks of the block, wherein the mode selection includes selecting a tree structure of the partitioned block 203, and a prediction mode is applied to each of the partitions or sub-blocks of the block.

[0083] Below, the partitioning (eg, by partitioning unit 260) and prediction processes (by inter-prediction unit 244 and intra-prediction unit 254) performed by exemplary video encoder 20 are described in more detail.

[0084] Division The partitioning unit 262 may partition (or divide) the current block 203 into smaller sections, e.g., square or rectangular sized smaller blocks. These smaller blocks (which may also be called subblocks) may be further partitioned into even smaller sections. This is also called tree partitioning or hierarchical tree partitioning; for example, a root block at root tree level 0 (hierarchical level 0, depth 0) may be recursively partitioned, e.g., into two or more blocks at the next lower tree level, e.g., nodes at tree level 1 (hierarchical level 1, depth 1), which may again be partitioned into two or more blocks at the next lower level, e.g., tree level 2 (hierarchical level 2, depth 2), and so on, until partitioning is terminated, e.g., because a termination criterion is met, e.g., a maximum tree depth or a minimum block size is reached. Blocks that are not further partitioned are also called leaf blocks or leaf nodes of the tree. A tree that uses a partition into two partitions is called a binary tree (BT), a tree that uses a partition into three partitions is called a ternary tree (TT), and a tree that uses a partition into four partitions is called a quad tree (QT).

[0085] As mentioned above, the term "block" as used herein may refer to a portion of a picture, particularly a square or rectangular portion. For example, in the context of HEVC and VVC, a block may be or correspond to a coding tree unit (CTU), a coding unit (CU), a prediction unit (PU), and a transform unit (TU), and / or a corresponding block, such as a coding tree block (CTB), a coding block (CB), a transform block (TB), or a prediction block (PB).

[0086] For example, a coding tree unit (CTU) may be or include a CTB of luma samples, two corresponding CTBs of chroma samples for a picture having a three-sample arrangement, or a CTB of samples for a picture coded using three separate color planes and a syntax structure used to code a monochrome picture or sample. Correspondingly, a coding tree block (CTB) may be an NxN block of samples for some value of N such that the division of the components into CTBs is a partition. A coding unit (CU) may be or include a coding block of luma samples, two corresponding coding blocks of chroma samples for a picture having a three-sample arrangement, or a coding block of samples for a picture coded using three separate color planes and a syntax structure used to code a monochrome picture or sample. Correspondingly, a coding block (CB) may be an MxN block of samples for some values ​​of M and N such that the division of the CTB into coding blocks is a partition.

[0087] For example, in an HEVC embodiment, a coding tree unit (CTU) may be divided into CUs by using a quadtree structure represented as a coding tree. The decision of whether to code a picture area using inter-picture (temporal) prediction or intra-picture (spatial) prediction is made at the CU level. Each CU may be further divided into one, two, or four PUs according to a PU partition type. Within one PU, the same prediction process is applied, and related information is transmitted to the decoder based on the PU. After obtaining residual blocks by applying a prediction process based on the PU partition type, the CU may be partitioned into transform units (TUs) by another quadtree structure similar to the coding tree for the CU.

[0088] For example, in an embodiment according to the latest video coding standard currently under development, called Versatile Video Coding (VVC), quadtree and binary tree (QTBT) partitioning is used to partition coding blocks. In the QTBT block structure, CUs can have either square or rectangular shapes. For example, coding tree units (CTUs) are first partitioned by a quadtree structure. The leaf nodes of the quadtree are further partitioned by a binary tree or ternary (or triple) tree structure. The leaf nodes of the partitioning tree are called coding units (CUs), and their segmentation is used for prediction and transform processing without any further partitioning. This means that CUs, PUs, and TUs have the same block size in the QTBT coding block structure. In parallel, multi-partitioning, such as ternary tree partitioning, has also been proposed to be used with the QTBT block structure.

[0089] In one example, mode select unit 260 of video encoder 20 may be configured to perform any combination of the partitioning techniques described herein.

[0090] As mentioned above, video encoder 20 is configured to determine or select a best or optimal prediction mode from a (predetermined) set of prediction modes, which may include, for example, intra-prediction modes and / or inter-prediction modes.

[0091] Intra prediction The set of intra prediction modes may include, for example, the 35 different intra prediction modes defined in HEVC, e.g., non-directional modes such as DC (or average) mode and planar mode, or directional modes, or may include, for example, the 67 different intra prediction modes defined for VVC, e.g., non-directional modes such as DC (or average) mode and planar mode, or directional modes.

[0092] The intra prediction unit 254 is configured to generate the intra prediction block 265 using reconstructed samples of neighboring blocks of the same current picture according to an intra prediction mode from a set of intra prediction modes.

[0093] The intra prediction unit 254 (or generally the mode selection unit 260) is further configured to output the intra prediction parameters (or generally information indicating the selected intra prediction mode for the block) to the entropy encoding unit 270 in the form of syntax elements 266 for inclusion in the encoded picture data 21, for example, so that the video decoder 30 may receive the prediction parameters and use them for decoding.

[0094] Inter Prediction The set (or possible) inter prediction modes depends on the available reference pictures (i.e., for example, previous at least partially decoded pictures stored in DBP230) as well as other inter prediction parameters, such as whether the entire reference picture is used to search for the best matching reference block or only a portion of the reference picture, for example, a search window area around the area of ​​the current block, and / or whether pixel interpolation, for example, half / semi-pel and / or quarter-pel interpolation, is applied.

[0095] In addition to the prediction modes mentioned above, skip mode and / or direct mode may also be applied.

[0096] The inter prediction unit 244 may include a motion estimation (ME) unit and a motion compensation (MC) unit (neither of which are shown in FIG. 2). The motion estimation unit may be configured to receive or obtain, for motion estimation, the picture block 203 (current picture block 203 of current picture 17) and the decoded picture 231, or at least one or more already reconstructed blocks, e.g., reconstructed blocks of one or more other / different already decoded pictures 231. For example, a video sequence may include the current picture and the already decoded picture 231, or in other words, the current picture and the already decoded picture 231 may be part of or form a sequence of pictures that form a video sequence.

[0097] The encoder 20 may be configured to, for example, select a reference block from multiple reference blocks of the same or different pictures among multiple other pictures, and provide the reference picture (or reference picture index) and / or an offset (spatial offset) between the position (x, y coordinates) of the reference block and the position of the current block to the motion estimation unit as an inter-prediction parameter. This offset is also called a motion vector (MV).

[0098] The motion compensation unit is configured to obtain, e.g., receive, inter prediction parameters and perform inter prediction based on or using the inter prediction parameters to obtain inter prediction block 265. The motion compensation performed by the motion compensation unit may include fetching or generating a prediction block based on motion / block vectors determined by motion estimation, possibly performing interpolation with sub-pixel accuracy. Interpolation filtering may generate additional pixel samples from known pixel samples, thus potentially increasing the number of candidate prediction blocks that may be used to code the picture block. Upon receiving a motion vector for the PU of the current picture block, the motion compensation unit may find the prediction block to which the motion vector points in one of the reference picture lists.

[0099] The motion compensation unit may also generate syntax elements associated with the blocks and video slices for use by video decoder 30 in decoding picture blocks of the video slices.

[0100] Entropy Coding The entropy coding unit 270 is configured to apply, for example, an entropy coding algorithm or scheme (e.g., a variable length coding (VLC) scheme, a context adaptive VLC scheme (CAVLC), an arithmetic coding scheme, binarization, context adaptive binary arithmetic coding (CABAC), syntax-based context-adaptive binary arithmetic coding (SBAC), probability interval partitioning entropy (PIPE) coding, or another entropy coding method or technique) or bypass (uncompressed) to the quantized coefficients 209, the inter-prediction parameters, the intra-prediction parameters, the loop filter parameters, and / or other syntax elements to obtain coded picture data 21 that may be output via an output 272, for example, in the form of coded bitstream 21, such that video decoder 30 may receive the parameters and use them for decoding. The encoded bitstream 21 may be transmitted to the video decoder 30 or stored in memory for later transmission or retrieval by the video decoder 30 .

[0101] Other structural variations of the video encoder 20 may be used to encode the video stream. For example, a non-transform-based encoder 20 may directly quantize the residual signal for a particular block or frame without a transform processing unit 206. In another implementation, the encoder 20 may have the quantization unit 208 and the inverse quantization unit 210 combined into a single unit.

[0102] Decoder and decoding method 3 shows an example of a video decoder 30 configured to implement the techniques of the present application. The video decoder 30 is configured to receive coded picture data 21 (e.g., coded bitstream 21), e.g., coded by encoder 20, to obtain a decoded picture 331. The coded picture data or bitstream includes information for decoding the coded picture data, e.g., data representing picture blocks of a coded video slice and associated syntax elements.

[0103] 3, decoder 30 includes an entropy decoding unit 304, an inverse quantization unit 310, an inverse transform processing unit 312, a reconstruction unit 314 (e.g., summer 314), a loop filter 320, a decoded picture buffer (DBP) 330, an inter prediction unit 344, and an intra prediction unit 354. Inter prediction unit 344 may be or include a motion compensation unit. Video decoder 30 may, in some examples, perform a decoding path that is generally the reverse of the encoding path described in connection with video encoder 100 of FIG. 2.

[0104] As described in connection with encoder 20, inverse quantization unit 210, inverse transform processing unit 212, reconstruction unit 214, loop filter 220, decoded picture buffer (DPB) 230, inter prediction unit 344, and intra prediction unit 354 are also considered to form a “built-in decoder” of video encoder 20. Accordingly, inverse quantization unit 310 may be functionally identical to inverse quantization unit 110, inverse transform processing unit 312 may be functionally identical to inverse transform processing unit 212, reconstruction unit 314 may be functionally identical to reconstruction unit 214, loop filter 320 may be functionally identical to loop filter 220, and decoded picture buffer 330 may be functionally identical to decoded picture buffer 230. Accordingly, the descriptions given with respect to the respective units and functions of video encoder 20 apply mutatis mutandis to the respective units and functions of video decoder 30.

[0105] Entropy Decoding The entropy decoding unit 304 is configured to parse the bitstream 21 (or the coded picture data 21 generally), e.g., to perform entropy decoding on the coded picture data 21 to obtain, e.g., quantized coefficients 309 and / or decoded coding parameters (not shown in FIG. 3 ), e.g., any or all of inter-prediction parameters (e.g., reference picture indices and motion vectors), intra-prediction parameters (e.g., intra-prediction modes or indices), transform parameters, quantization parameters, loop filter parameters, and / or other syntax elements. The entropy decoding unit 304 may be configured to apply a decoding algorithm or scheme corresponding to the encoding scheme described in connection with the entropy coding unit 270 of the encoder 20. The entropy decoding unit 304 may be further configured to provide the inter-prediction parameters, intra-prediction parameters, and / or other syntax elements to the mode selection unit 360 and to provide other parameters to other units of the decoder 30. The video decoder 30 may receive syntax elements at the video slice level and / or the video block level.

[0106] inverse quantization Inverse quantization unit 310 may be configured to receive a quantization parameter (QP) (or information generally related to inverse quantization) and quantized coefficients from encoded picture data 21 (e.g., by parsing and / or decoding by entropy decoding unit 304), and apply inverse quantization to the decoded quantized coefficients 309 based on the quantization parameter to obtain inverse quantized coefficients 311, which may also be referred to as transform coefficients 311. The inverse quantization process may include using the quantization parameter determined by video encoder 20 for each video block within a video slice to determine the degree of quantization and, similarly, the degree of inverse quantization to be applied.

[0107] Inverse transformation The inverse transform processing unit 312 may be configured to receive the dequantized coefficients 311, also referred to as transform coefficients 311, and apply a transform to the dequantized coefficients 311 to obtain reconstructed residual blocks 213 in the sample domain. The reconstructed residual blocks 213 may also be referred to as transform blocks 213. The transform may be an inverse transform, e.g., an inverse DCT, an inverse DST, an inverse integer transform, or a conceptually similar inverse transform process. The inverse transform processing unit 312 may further be configured to receive transform parameters or corresponding information from the coded picture data 21 (e.g., by parsing and / or decoding by the entropy decoding unit 304) to determine the transform to apply to the dequantized coefficients 311.

[0108] Rebuild The reconstruction unit 314 (e.g., an adder or summer 314) may be configured to add the reconstructed residual block 313 to the prediction block 365, for example, by adding the sample values ​​of the reconstructed residual block 313 and the sample values ​​of the prediction block 365, to obtain a reconstructed block 315 in the sample domain.

[0109] filtering Loop filter unit 320 (either in the coding loop or after the coding loop) is configured to filter reconstructed block 315 to, for example, smooth pixel transitions or otherwise improve video quality to obtain filtered block 321. Loop filter unit 320 may include one or more loop filters, such as a deblocking filter, a sample adaptive offset (SAO) filter, or one or more other filters, such as a bilateral filter, an adaptive loop filter (ALF), a sharpening filter, a smoothing filter, or a collaborative filter, or any combination thereof. Although loop filter unit 320 is shown in FIG. 3 as being an in-loop filter, in other configurations, loop filter unit 320 may be implemented as a post-loop filter.

[0110] Decoded Picture Buffer The decoded video blocks 321 of the picture are then stored in a decoded picture buffer 330, which stores the decoded picture 331 as a reference picture for subsequent motion compensation with respect to other pictures and / or for output on a display, respectively.

[0111] The decoder 30 is configured to output the decoded pictures 311 for presentation or viewing to a user, for example via an output 312.

[0112] prediction The inter prediction unit 344 may be identical to the inter prediction unit 244 (especially the motion compensation unit), and the intra prediction unit 354 may be functionally identical to the inter prediction unit 254, and performs the partitioning or partitioning decision and prediction based on the partitioning and / or prediction parameters or respective information received from the decoded picture data 21 (e.g., by analyzing and / or decoding by the entropy decoding unit 304). The mode selection unit 360 may be configured to perform prediction (intra or inter prediction) for each block based on the (filtered or unfiltered) reconstructed picture, block, or respective sample to obtain a prediction block 365.

[0113] When a video slice is coded as an intra-coded (I) slice, intra prediction unit 354 of mode select unit 360 is configured to generate a predictive block 365 for a picture block of the current video slice based on the signaled intra prediction mode and data from already decoded blocks of the current picture. When a video picture is coded as an inter-coded (i.e., B or P) slice, inter prediction unit 344 (e.g., a motion compensation unit) of mode select unit 360 is configured to generate a predictive block 365 for a video block of the current video slice based on the motion vector and other syntax elements received from entropy decoding unit 304. For inter prediction, the predictive block may be generated from one of the reference pictures in one of the reference picture lists. Video decoder 30 may construct the reference frame lists, List 0 and List 1, using a default construction technique based on the reference pictures stored in DPB 330.

[0114] Mode select unit 360 is configured to determine prediction information for video blocks of the current video slice by parsing motion vectors and other syntax elements, and use the prediction information to generate a predictive block for the current video block being decoded. For example, mode select unit 360 uses some of the received syntax elements to determine the prediction mode (e.g., intra or inter prediction) used to code the video blocks of the video slice, the slice type for inter prediction (e.g., B slice, P slice, or GPB slice), construction information for one or more of the reference picture lists for the slice, motion vectors for each inter-coded video block of the slice, the status of inter prediction for each inter-coded video block of the slice, and other information for decoding video blocks in the current video slice.

[0115] Other variations of the video decoder 30 may be used to decode the coded picture data 21. For example, the decoder 30 may generate an output video stream without the loop filtering unit 320. For example, a non-transform-based decoder 30 may directly inverse quantize the residual signal for a particular block or frame without the inverse transform processing unit 312. In another implementation, the video decoder 30 may have the inverse quantization unit 310 and the inverse transform processing unit 312 combined into a single unit.

[0116] It should be understood that in the encoder 20 and the decoder 30, the processing result of the current step may be further processed and then output to the next step. For example, after interpolation filtering, motion vector derivation, or loop filtering, further operations such as Clip or Shift may be performed on the processing result of the interpolation filtering, motion vector derivation, or loop filtering.

[0117] It should be noted that further operations may be applied to the derived motion vector of the current block (including, but not limited to, control point motion vectors in affine mode, lower-block motion vectors in affine, planar, and ATMVP modes, temporal motion vectors, etc.). For example, the value of the motion vector is constrained to a predetermined range according to its representation bits. If the representation bits of the motion vector are bitDepth, then the range is -2^(bitDepth-1) to 2^(bitDepth-1)-1, where "^" means exponentiation. For example, if bitDepth is set equal to 16, the range is -32768 to 32767, and if bitDepth is set equal to 18, the range is -131072 to 131071. Here, two methods are provided for constraining the motion vector.

[0118] Method 1: Delete the overflow MSB (Most Significant Bit) by flowing operation ux= ( mvx+2 bitDepth ) % 2 bitDepth (1) mvx = ( ux >= 2 bitDepth-1 ) ? (ux - 2 bitDepth ) : ux (2) uy= ( mvy+2 bitDepth ) % 2 bitDepth (3) mvy = ( uy >= 2 bitDepth-1 ) ? (uy - 2 bitDepth ) : uy (4)

[0119] For example, if the value of mvx is -32769, after applying equations (1) and (2), the resulting value is 32767. In computer systems, decimal numbers are stored as two's complement numbers. The two's complement of -32769 is 1, 0111, 1111, 1111, 1111 (17 bits), then the MSB is discarded, therefore the resulting two's complement is 0111, 1111, 1111, 1111 (decimal 32767), which is the same as the output by applying equations (1) and (2). ux= ( mvpx + mvdx +2 bitDepth ) % 2 bitDepth (5) mvx = ( ux >= 2 bitDepth-1 ) ? (ux - 2 bitDepth ) : ux (6) uy= ( mvpy + mvdy +2 bitDepth ) % 2 bitDepth (7) mvy = ( uy >= 2 bitDepth-1 ) ? (uy - 2 bitDepth ) : uy (8)

[0120] The operations may be applied during the summation of mvp and mvd as shown in equations (5) to (8).

[0121] Method 2: Remove overflowing MSB by clipping the value vx = Clip3(-2 bitDepth-1 , 2 bitDepth-1 -1, vx) vy = Clip3(-2 bitDepth-1 , 2 bitDepth-1 -1, vy) The function Clip3 is defined as follows:

number

[0122] 4 is a schematic diagram of a video coding device 400 according to an embodiment of the present disclosure. The video coding device 400 is suitable for implementing the disclosed embodiments as described herein. In an embodiment, the video coding device 400 may be a decoder, such as the video decoder 30 of FIG. 1A, or an encoder, such as the video encoder 20 of FIG. 1A.

[0123] Video coding device 400 includes an incoming port 410 (or input port 410) and a receiver unit (Rx) 420 for receiving data, a processor, logic unit, or central processing unit (CPU) 430 for processing data, a transmitter unit (Tx) 440 and an outgoing port 450 (or output port 450) for transmitting data, and a memory 460 for storing data. Video coding device 400 may also include optical-electrical (OE) and electrical-optical (EO) components coupled to the incoming port 410, receiver unit 420, transmitter unit 440, and outgoing port 450 for emitting or receiving optical or electrical signals.

[0124] The processor 430 is implemented by hardware and software. The processor 430 may be implemented as one or more CPU chips, cores (e.g., as a multi-core processor), FPGA, ASIC, and DSP. The processor 430 communicates with the incoming port 410, the receiver unit 420, the transmitter unit 440, the outgoing port 450, and the memory 460. The processor 430 includes a coding module 470. The coding module 470 implements the disclosed embodiments described above. For example, the coding module 470 implements, processes, prepares, or provides various coding operations. Thus, the inclusion of the coding module 470 significantly improves the functionality of the video coding device 400 and results in the transition of the video coding device 400 to different states. Alternatively, the coding module 470 is implemented as instructions stored in the memory 460 and executed by the processor 430.

[0125] Memory 460 may include one or more disks, tape drives, and solid-state drives, and may be used as an overflow data storage device for storing programs when such programs are selected for execution and for storing instructions and data read during execution of the programs. Memory 460 may be, for example, volatile and / or non-volatile, and may be read-only memory (ROM), random access memory (RAM), ternary content-addressable memory (TCAM), and / or static random access memory (SRAM).

[0126] FIG. 5 is a simplified block diagram of an apparatus 500 that may be used as either or both of source device 12 and destination device 14 of FIG. 1, according to an exemplary embodiment.

[0127] Processor 502 of apparatus 500 may be a central processing unit. Alternatively, processor 502 may be any other type of device or devices, existing or later developed, that are capable of manipulating or processing information. While the disclosed implementations may be performed by a single processor, e.g., processor 502, as shown, speed and efficiency advantages may be realized by using two or more processors.

[0128] The memory 504 of the apparatus 500 may, in implementation, be a read-only memory (ROM) device or a random-access memory (RAM) device. Any other suitable type of storage device may be used as the memory 504. The memory 504 may include code and data 506 accessed by the processor 502 using a bus 512. The memory 504 may further include an operating system 508 and application programs 510, which include at least one program that enables the processor 502 to perform the methods described herein. For example, the application programs 510 may include applications 1 through N, which further include a video coding application that performs the methods described herein.

[0129] The apparatus 500 may also include one or more output devices, such as a display 518. The display 518, in one example, may be a touch-sensitive display that combines a display with touch-sensing elements operable to sense touch input. The display 518 may be coupled to the processor 502 via the bus 512.

[0130] Although shown here as a single bus, bus 212 of device 500 may be comprised of multiple buses. Additionally, secondary storage 514 may be directly coupled to other components of device 500 or may be accessed over a network, and may include a single integrated unit such as a memory card or multiple units such as multiple memory cards. Accordingly, device 500 may be implemented in a wide variety of configurations.

[0131] In the example of building a merge candidate list according to ITU-T H.265, the merge candidate list is built based on the following candidates: 1. Up to four spatial candidates derived from five spatially neighboring blocks; 2. One temporal candidate derived from two temporally co-located blocks; 3. Additional candidates, including combined bi-predictive candidates; and 4. Zero motion vector candidates

[0132] spatial candidate The motion information of spatially neighboring blocks is first added to the merge candidate list as motion information candidates (in an example, the merge candidate list may be an empty list before the first motion vector is added to the merge candidate list). Here, the neighboring blocks that may be inserted into the merge list are shown in Figure 6b. For inter-prediction block merging, up to four candidates are inserted into the merge list by sequentially examining A1, B1, B0, A0, and B2 in this order.

[0133] The motion information may include all motion data, including information on whether one or two reference picture lists are used, as well as reference indexes and motion vectors for each reference picture list.

[0134] In the example, after checking whether the neighboring blocks are available and whether they contain motion information, some further redundancy checks are performed before considering all the motion data of the neighboring blocks as motion information candidates. These redundancy checks can be divided into two categories for two different purposes: Category 1, avoid having candidates with redundant motion data in the list. Category 2, which produces redundant syntax and prevents merging two parcels that could be expressed by other means.

[0135] temporal candidate 6a shows the coordinates of blocks from which temporal motion information candidates are retrieved. A co-located block is a block that has the same -x, -y coordinates as the current block but is on a different picture (one of the reference pictures). A temporal motion information candidate is added to a merge list if the list is not full (in an example, a merge list is not full when the amount of candidates in the merge list is less than a threshold, for example, the threshold may be 4, 5, 6, etc.).

[0136] Generated candidates If the merge list is not yet full after the insertion of the spatial and temporal motion information candidates, the generated candidates are added to fill the list. The list size is indicated in the sequence parameter set and is fixed throughout the coded video sequence.

[0137] The merge list construction process for ITU-T H.265 and VVC outputs a list of motion information candidates. The merge list construction process for VVC is described in the document JVET-L1001_v2 Versatile Video Coding (Draft 3), published at http: / / phenix.it-sudparis.eu / jvet / , in section "8.3.2.2 Derivation process for luma motion vectors for merge mode." The term motion information refers to the motion data required to perform the motion compensation prediction process. Motion information typically refers to the following information: Whether the block is uni- or bi-predictive The ID of the reference picture used in the prediction (two IDs if the block applies bi-prediction). Motion vector (two motion vectors if the block is bi-predicted) Additional Information

[0138] In VVC and H.265, the list of candidates that is the output of the merge list construction includes N candidate motion information. The number N is generally included in the bitstream and can be a positive integer, such as 5, 6, etc. The candidates included in the constructed merge list may include uni-predictive or bi-predictive information. This means that the candidates selected from the merge list may exhibit bi-predictive behavior.

[0139] Bi-prediction A special mode of inter-prediction is called "bi-prediction," in which two motion vectors are used to predict a block. The motion vectors may point to the same or different reference pictures, which may be indicated by a reference picture list ID and a reference picture index. For example, a first motion vector may point to the first picture of a reference picture list L0, and a second motion vector may point to the first picture of a reference picture list L1. Two reference picture lists (e.g., L0 and L1) may be maintained, with the picture pointed to by the first motion vector selected from list L0 and the picture pointed to by the second motion vector selected from list L1.

[0140] In an example, if the motion information indicates bi-prediction, then the motion information includes the following two parts: L0 part: motion vectors and reference picture indices pointing to entries in the reference picture list L0 L1 part: motion vectors and reference picture indices pointing to entries in the reference picture list L1

[0141] Picture Order Count (POC): A variable associated with each picture that uniquely identifies the associated picture among all pictures in a CVS (Coded Video Sequence) and indicates the position of the associated picture in output order relative to the output order positions of other pictures in the same CVS that should be output from the decoded picture buffer when the associated picture is to be output from the decoded picture buffer.

[0142] Each of the reference picture lists L0 and L1 may include one or more reference pictures, each identified by a POC. The association of each reference index with a POC value may be signaled in the bitstream. As an example, the L0 and L1 reference picture lists may include the following reference pictures: [Table 1]

[0143] In the above example, the first entry (indicated by reference index 0) of reference picture list L1 is a reference picture with a POC value of 13. The second entry (indicated by reference index 1) of reference picture list L1 is a reference picture with a POC value of 14.

[0144] Triangular prediction mode The concept of triangular prediction mode is to introduce a triangular partition for motion compensation prediction. As an example shown in Figure 7, two triangular prediction units are used for a CU in either the diagonal or anti-diagonal direction. Each triangular prediction unit in a CU is inter-predicted using a uni-predictive motion vector and a reference frame index derived from a uni-predictive candidate list. An adaptive weighting process is performed on the diagonal edge after the samples associated with each triangular prediction unit are predicted, for example, by motion compensation or intra-picture prediction. Then, a transform and quantization process are applied to the entire CU. It is noted that this mode only applies to skip mode and merge mode.

[0145] In triangular prediction mode, a block is divided into two triangular parts (as in FIG. 7), and each part can be predicted using one motion vector. The motion vector used to predict one triangular part (represented by PU1) can be different from the motion vector used to predict the other triangular part (represented by PU2). In the example, it is noted that to reduce the complexity of performing the triangular prediction mode, each part can be predicted using only a single motion vector (uni-prediction). In other words, PU1 and PU2 do not need to be predicted using bi-prediction involving two motion vectors.

[0146] Lower Block Prediction Mode Triangular prediction mode is a special case of sub-block prediction, in which a block is divided into two blocks. In the above example, two block division directions are shown (45-degree partition and 135-degree partition). It is noted that other partition angles and partition ratios are also possible (example of Figure 8).

[0147] In some examples, a block is divided into two sub-block portions, and each portion needs to apply uni-prediction. Sub-block prediction represents a generalized version of triangular prediction.

[0148] In the example, depending on the used subblock partitioning mode, the following steps are applied to obtain the predicted samples: Step 1: Divide the coding block into two sub-blocks by a geometric model. This model may result from dividing the block by a dividing line (for example, a straight line) as illustrated in Figures 9 to 12. It may be understood that the result of step 1 may be merely a concept. For example, after step 1, there is no clear concept of "sub-block 1" or "sub-block 2", and generating or obtaining parameters refers to the dividing line. Samples may belong to different sub-blocks according to the parameters that refer to the dividing line. In this step, according to the geometric model, the samples of a coding block are considered to be in two sub-blocks. Sub-block A or sub-block B contains some (but not all) of the samples of the current coding block. Sub-block A or sub-block B may be represented by the code of sample_dist of each sample. sample_dist may be obtained according to the examples and embodiments in other paragraphs. Step 2: Obtain a first prediction mode for the first sub-block and a second prediction mode for the second sub-block. In an example, the first prediction mode is not the same as the second prediction mode. In an example, the prediction mode (the first prediction mode or the second prediction mode) may be an inter prediction mode, and the information for the inter prediction mode may include a reference picture index and a motion vector. In another example, the prediction mode may be an intra prediction mode, and the information for the intra prediction mode may include an intra prediction mode index. Step 3: Obtaining a first predicted value and a second predicted value using the first prediction mode and the second prediction mode, respectively. Step 4: Obtain a combined value of the predicted sample by combining the first predicted value and the second predicted value according to the division disclosed in step 1. The process of combining samples from the first prediction and the second prediction to obtain a combined value of the predicted sample of the block may include a filtering operation, a masking operation, or copying of the samples.

[0149] In the example, in step 1, a coding block is divided into two sub-blocks in various ways. Figure 9 shows an example of a coding block partition, where a dividing line 1250 divides the block into two sub-blocks. To indicate the line 1250, two parameters are signaled: one parameter is the angle alpha 1210, and the other parameter is the distance dist 1230.

[0150] In some embodiments, the angle is measured between the x-axis and the dividing line, as shown in FIG. 9, while the distance is measured by the length of a vector perpendicular to the dividing line and passing through the center of the current block.

[0151] In another example, FIG. 10 shows an alternative way of representing the dividing line, with example angles and distances that differ from the example shown in FIG.

[0152] In some examples, in step 4, the splitting disclosed in step 1 is used to combine the first and second predicted values ​​to obtain a final predicted value.

[0153] In the example, a blending operation is applied in step 4 to eliminate any artifacts (sharp or jagged appearance along the dividing lines). The blending operation can be described as a filtering operation along the dividing lines.

[0154] At the encoder side, a dividing line (parameters defining the line, e.g., angle and distance) is determined based on a rate-distortion-based cost function. The determined line parameters are coded into a bitstream. At the decoder side, the line parameters are decoded (obtained) by the bitstream. At the decoder side, the line parameters are used to combine the first predicted value and the second predicted value to obtain a final predicted value. Step 1 does not require that there is a concept of two lower-level coding blocks; the decoder can represent the concept of two lower-level coding blocks using coding blocks and line parameters.

[0155] In an example, for three video channels including a luminance component and two chrominance components, a first prediction and a second prediction are generated for each channel.

[0156] Because there are many possibilities to divide a coding block into two sub-blocks, signaling (coding) the division (or partitioning) requires many bits. Because the angle and distance values ​​can have many different values, which requires too much side information to be signaled in the bitstream, a quantization scheme is applied to the angle and distance side information to improve coding efficiency.

[0157] An embodiment of the present invention is directed to the signaling of segmentation parameters, for example the quantized angle parameter alphaIdx and the quantized distance parameter distanceIdx.

[0158] In the example, in the quantization scheme, the angle values ​​and distance values ​​are alphaIdx = Round(alpha / Δalpha) distanceIdx = Round(dist / Δdist) where the variable Δalpha represents the quantization step size for the angle parameter division line, and Δdist represents the quantization step size for the distance parameter of the division line. Thus, the angle alpha and the distance dist can be calculated using the values ​​of alphaIdx and distanceIdx obtained from the bitstream. alpha = alphaIdx*Δalpha dist = distanceIdx*Δdist It may be reconstructed as follows:

[0159] In an example, if the angle quantization step size is equal to Δalpha = 11.25°, the value of alphaIdx may range from 0 to 31, inclusive, to encompass the allowable angles in the Euclidean plane. In another example, the angle quantization step size value is equal to Δalpha = 22.5°, whereby the value of alphaIdx may range from 0 to 15, inclusive.

[0160] In some embodiments, a method is disclosed for quantizing distance information according to the angular dimension where a linear uniform quantizer is used to quantize the angular dimension, i.e., the value of Δalpha is constant for a given coding (decoding or encoding) block.

[0161] The objective of the disclosed quantization scheme is to evenly distribute the allowable dividing lines for a given coding block, which may have different sizes and aspect ratios. The evenly distributed space of quantized angle and distance parameters improves coding efficiency for non-rectangular components and allows for a compact representation of dividing line parameters.

[0162] In some embodiments, a method for partitioning a rectangular coding block by straight lines, the straight lines being parameterized by a pair of parameters representing a quantized angle and a quantized distance value, the quantized distance value being derived by a quantization process depending on the angle value and the aspect ratio of the coding block.

[0163] In an example, the distance may be quantized such that a given numerical range of distanceIdx is filled, for example, a numerical range from 0 to 3 inclusive. In another example, the distance may be quantized for a given block such that the dividing lines for a given pair of angleIdx and distanceIdx values ​​are evenly distributed and such that the dividing lines never lie outside the area of ​​the given coding block.

[0164] In the first step, the maximum distance ρ max However, the distance value 0 < dist < ρ max may be derived according to angle such that all division lines with σ are constrained to the coding block (e.g., they intersect the boundary of the coding block). This is illustrated in Figure 15 for a coding block of size 16x4 luma samples.

[0165] In the example, the maximum distance ρ max teeth,

number

[0166] In another example, the value of the quantization step size of the angle-dependent distance is Δdist(alphaR,w,h) = (ρ max (alphaR,w,h) -ρ th ) / N where ρ th is a parameter used to modify the spacing between the dividing lines for the coding block. th The value of ρ th = 1.5.

[0167] In another example, the maximum distance ρ max teeth,

number

[0168] In an example, the value of Δdist, which depends on the values ​​of the angle parameter, the width parameter, and the height parameter, may be stored in a pre-calculated lookup table to avoid repeated calculation of Δdist during the encoding or decoding process.

[0169] In an embodiment, the value of Δdist is stepD = Round(Δdist*2 prec ) where stepD represents the step size of the linearly scaled distance and prec is a variable used to adjust the precision of the scaling process. In the example, the value of prec is set to prec=7.

[0170] In the example, also stored is a pre-calculated value of stepD based on an aspect ratio, denoted whRatio, where the aspect ratio value depends on the width and height of the coding block. Additionally, a pre-calculated value of stepD based on a (normalized) angle value angleN (e.g., 0≦angleN*Δalpha≦90°), which is an index value related to an angle in the first quadrant of the Euclidean plane, is stored. An example of such a lookup table with the above-mentioned simplifications applied can be seen in Figure 13.

[0171] In one embodiment, the following steps are applied to obtain predictions for the samples of a coding block.

[0172] Step 1: For samples in the current block (decoded or coded block), the sample distance (sample_dist) is calculated.

[0173] In some examples, the distance of a sample may represent the horizontal distance, vertical distance, or a combination of vertical and horizontal distance of the sample to a dividing line, which is used to divide the coding block into two sub-blocks. The sample is represented by coordinates (x, y) relative to the top-left sample of the coding block. Sample coordinates (x, y) and sample_dist are illustrated in Figures 11 and 12. The sub-blocks are not necessarily rectangular; they may be triangular or trapezoidal.

[0174] In an example, the first parameter represents a quantized angle value (angleIdx), and the second parameter represents a quantized distance value (distanceIdx). The two parameters indicate the equation of a line. In an example, the distance 1230 can be obtained according to distanceIdx (the second parameter), and the angle alpha 1210 can be obtained according to angleIdx (the first parameter). The distance 1230 can be the distance of the dividing line to the center of the coding block, and the angle can be the angle between the dividing line and a horizontal (or equivalently vertical) line passing through the center point of the coding block.

[0175] In a particular example, the values ​​of angleIdx and distanceIdx are obtained based on the shape of the partition in the geometric partitioning merge mode (indicated by merge_gpm_partition_idx). For example, the relationship between these values ​​is shown in Table 1. It can be understood that in implementation, this relationship can be implemented according to Table 1 or by a function. [Table 2]

[0176] In the example, in step 1, a coding block is divided into two sub-blocks in various ways. Figure 9 shows an example of a coding block partition, where a dividing line 1250 divides the block into two sub-blocks. To indicate the line 1250, one angle parameter alpha 1210 is signaled in the bitstream.

[0177] In some embodiments, the angle is measured between the x-axis and the dividing line, as shown in FIG. 9, while the distance is measured by the length of a vector perpendicular to the dividing line and passing through the center of the current block.

[0178] In another example, FIG. 10 shows an alternative way of representing the dividing line, with example angles and distances that differ from the example shown in FIG.

[0179] Step 2: The calculated sample_dist is used to calculate weighting factors, which are used for combining the first predicted value and the second predicted value corresponding to the sample. In the example, the weighting factors are denoted as sampleWeight1 and sampleWeight2, which refer to the weight corresponding to the first predicted value and the weight corresponding to the second predicted value.

[0180] In one example, the weighting factor is a function of: weightIdxL = partFlip ? 32 + sample_dist : 32 - sample_dist wValue = Clip3( 0, 8, ( weightIdxL + 4 ) >> 3 ) It is calculated by:

[0181] In this example, wValue is sampleWeight1, and 8 - wValue is sampleWeight2. The variable partFlip is determined according to the value of angleIdx. In the example, partFlip = ( angleIdx >= 13 && angleIdx <= 27 ) ? 0 : 1, or partFlip = ( angleIdx >= 13 && angleIdx <= 27 ) ? 1 : 0.

[0182] Step 3: A combined value of the predicted sample at the sample coordinate (x, y) is calculated according to the first predicted value at the coordinate (x, y), the second predicted value at the coordinate (x, y), sampleWeight1, and sampleWeight2.

[0183] In the example, the predicted sample values ​​are derived as follows: pbSamples[ x ][ y ] = Clip3( 0, ( 1 << BitDepth ) - 1, ( predSamplesLA[ x ][ y ] * wValue + predSamplesLB[ x ][ y ] * ( 8 - wValue ) + offset1 ) >> shift1 )

[0184] In the formula, bitDepth represents the bit depth of the samples, the variable shift1 is obtained according to bitDepth, in the example, shift1 = Max(5, 17 - BitDepth), the variable offset1 is obtained according to shift1, in the example, offset1 = 1 << (shift1 - 1), and predSamplesLA and predSamplesLB are two (nCbW) x (nCbH) arrays.

[0185] In an embodiment, according to an example, step 1 of the above embodiment may include the following steps:

[0186] Step 1.1: Obtain the index value of the angle parameter for the current block (alphaN or angleIdx), the width value of the current block (W), and the height value of the current block (H). W and H are the width and height of the current block expressed in number of samples. For example, a coding block having a width and height both equal to 8 is a square block containing 64 samples. In another example, W and H are the width and height of the current block expressed in number of luma samples. The index values ​​of the angle parameters may be obtained according to the above description with reference to Table 1.

[0187] Step 1.2: Obtain a value of the ratio whRatio according to the value of W and the value of H, where the value of whRatio represents the ratio between the width and height of the current coding block.

[0188] In the example, whRatio = H / W or whRatio = W / H.

[0189] In another example, two variables, nCbW and nCbH, specify the width and height of the current coding block, and the variable cIdx specifies the color component index.

[0190] The variables nW, nH, and whRatio are derived as follows: nW = ( cIdx == 0 ) ? nCbW : nCbW * SubWidthC nH = ( cIdx == 0 ) ? nCbH : nCbH * SubHeightC whRatio = nH / nW

[0191] In the example, the variables SubWidthC and SubHeightC are specified in Table 2 according to the sampling structure of the chroma format specified by chroma_format_idc (chroma_format_idc specifies the chroma sampling relative to the luma sampling) and separate_colour_plane_flag (separate_colour_plane_flag equal to 1 specifies that the three color components of a 4:4:4 chroma format are coded separately. Separate_colour_plane_flag equal to 0 specifies that the color components are not coded separately. When separate_colour_plane_flag is not present, separate_colour_plane_flag is inferred to be 0. When separate_colour_plane_flag is equal to 1, the coded picture consists of three separate components, each of which consists of coded samples of one color plane (Y, Cb, or Cr), and uses monochrome coding syntax. In this case, each color plane is associated with a specific color_plane_id value). Other values ​​for chroma_format_idc, SubWidthC, and SubHeightC may be specified in the future by ITU T | ISO / IEC.

[0192] [Table 3]

[0193] In monochrome sampling, there is only one sample array, which is nominally considered the luma array. In 4:2:0 sampling, each of the two chroma arrays has half the height and half the width of the luma array. In 4:2:2 sampling, each of the two chroma arrays has the same height and half the width of the luma array. For 4:4:4 sampling, depending on the value of separate_colour_plane_flag the following applies: - If separate_colour_plane_flag is equal to 0, each of the two chroma arrays has the same height and width as the luma array. - Otherwise (separate_colour_plane_flag equals 1), the three colour planes are treated separately as a monochrome sampled picture.

[0194] Step 1.3: Obtain the value of stepD according to the lookup table, the value of alpha, and the value of whRatio. In an example, as shown in FIG. 13, the value of alpha (alphaN or angleIdx) and the value of whRatio are used as index values ​​of the lookup table. The value of stepD can also be obtained according to a function, where the value of alpha (alphaN or angleIdx) and the value of whRatio are input to the function, and the value of stepD is the output of the function. In an example, the result of the function is similar to or the same as the lookup table. In an example, the value of stepD represents the quantization step size for the sample distance calculation process.

[0195] In another example, the function may be represented by stepD = ( angleIdx % 16 == 8 || ( angleIdx % 16 != 0 && whRatio > 0 ) ) ? 0 : 1.

[0196] Step 1.4: The value of sample_dist is calculated according to the value of stepD.

[0197] In the example, to calculate the sample distance (sample_dist), first the variables offsetX and offsetY are derived as follows: If stepD is equal to 0, the following applies: offsetX = ( -nW ) >> 1, offsetY = ( ( -nH ) >> 1 ) + ( angleIdx < 16 ? ( distanceIdx * nH ) >> 3 : -( ( distanceIdx * nH ) >> 3 ) ) Otherwise (stepD equals 1), the following applies: offsetX = ( ( -nW ) >> 1 ) + ( angleIdx < 16 ? ( distanceIdx * nW ) >> 3 : -( ( distanceIdx * nW ) >> 3 ) ) offsetY = ( -nH ) >> 1 The variables xL and yL are derived as follows: xL = ( cIdx == 0 ) ? x : x * SubWidthC yL = ( cIdx == 0 ) ? y : y * SubHeightC sample_dist = ( ( ( xL + offsetX ) << 1 ) + 1 ) * disLut[ displacementX ] + ( ( ( yL + offsetY ) << 1 ) + 1 ) ) * disLut[ displacementY ] The variables displacementX and displacementY are derived as follows: hwRatio = cbHeight / cbWidth displacementX = angleIdx displacementY = (angleIdx + 8) % 32

[0198] The array disLut is defined in Table 3 as follows: [Table 4]

[0199] In another embodiment, in the example, step 1 of the above embodiment may include the following steps:

[0200] Step 1.1: Obtain the angle parameter value (alphaN or angleIdx) for the current block, the distance index value (distanceIdx), the width value (W) of the current block, and the height value (H) of the current block. W and H are the width and height of the current block expressed in number of samples. For example, a coding block having a width and height both equal to 8 is a square block containing 64 samples. In another example, W and H are the width and height of the current block expressed in number of luma samples. The index values ​​of the angle parameters may be obtained according to the above description with reference to Table 1.

[0201] Step 1.2: Obtain a value of the ratio whRatio according to the value of W and the value of H, where the value of whRatio represents the ratio between the width and height of the current coding block.

[0202] In the example, whRatio = H / W or whRatio = W / H.

[0203] In another example, two variables, nCbW and nCbH, specify the width and height of the current coding block, and the variable cIdx specifies the color component index.

[0204] The variables nW, nH, and whRatio are derived as follows: nW = ( cIdx == 0 ) ? nCbW : nCbW * SubWidthC nH = ( cIdx == 0 ) ? nCbH : nCbH * SubHeightC whRatio = nH / nW

[0205] Step 1.3: Obtain the value of stepD according to the lookup table, the value of alpha, and the value of whRatio. In the example, as shown in FIG. 13, the value of alphaN and the value of whRatio are used as index values ​​of the lookup table. In the example, the value of stepD represents the quantization step size for the sample distance calculation process. It can be understood that the value of stepD can also be obtained according to a function, where the value of alpha (alphaN or angleIdx) and the value of whRatio are input to the function, and the value of stepD is the output of the function. In the example, the result of the function is similar to or the same as the lookup table. In the example, the value of stepD represents the quantization step size for the sample distance calculation process.

[0206] In another example, the function may be represented by stepD = ( angleIdx % 16 == 8 || ( angleIdx % 16 != 0 && whRatio > 0 ) ) ? 0 : 1.

[0207] Step 1.4: The value of sample_dist is calculated according to the value of stepD, the value of distanceIdx, the value of angle (alphaN or angleIdx), the value of W, and the value of H.

[0208] In the example, to calculate the sample distance (sample_dist), first the variables offsetX and offsetY are derived as follows: If stepD is equal to 0, the following applies: offsetX = ( -nW ) >> 1, offsetY = ( ( -nH ) >> 1 ) + ( angleIdx < 16 ? ( distanceIdx * nH ) >> 3 : -( ( distanceIdx * nH ) >> 3 ) ) Otherwise (stepD equals 1), the following applies: offsetX = ( ( -nW ) >> 1 ) + ( angleIdx < 16 ? ( distanceIdx * nW ) >> 3 : -( ( distanceIdx * nW ) >> 3 ) ) offsetY = ( -nH ) >> 1 The variables xL and yL are derived as follows: xL = ( cIdx == 0 ) ? x : x * SubWidthC yL = ( cIdx == 0 ) ? y : y * SubHeightC sample_dist = ( ( ( xL + offsetX ) << 1 ) + 1 ) * disLut[ displacementX ] + ( ( ( yL + offsetY ) << 1 ) + 1 ) ) * disLut[ displacementY ]

[0209] The variables displacementX and displacementY are derived as follows: hwRatio = cbHeight / cbWidth displacementX = angleIdx displacementY = (angleIdx + 8) % 32

[0210] The sequence disLut is defined in Table 3 above.

[0211] In one example, the value of whRatio is calculated using the formula whRatio = (wIdx >= hIdx) ? wIdx - hIdx : hIdx - wIdx where the value of wIdx is equal to log2(W) - 3 and the value of hIdx is equal to log2(H) - 3.

[0212] In another example, the value of whRatio is calculated as whRatio = (W >= H) ? W / H : H / W.

[0213] In an embodiment of the present invention, the value of angle alpha may be obtained from the bitstream (at the decoder). In one example, the numerical range of the angle is a quantized numerical range from 0 to 31 (inclusive), represented as angleIdx. In one example, the quantized angle value takes on only 32 different distinct values ​​(thus, a value from 0 to 31 is sufficient to represent which angle value is selected). In another example, the numerical range of the angle value may be 0 to 15, i.e., 16 different quantized angle values ​​may be selected. It is noted that, in general, the angle value may be an integer value greater than 0.

[0214] In one example, the value of alphaN is an index value obtained from the bitstream, or the value of alpha is calculated based on the value of the indicator obtained from the bitstream. For example, the value of alphaN is calculated using the formula: alphaN= angleIdx if angleIdx >= 0 && angleIdx <=Lim, or alphaN = 2*Lim - angleIdx if angleIdx > Lim && angleIdx <= 2*Lim, or alphaN = angleIdx - 2*Lim if angleIdx > 2*Lim && angleIdx <=3*Lim, or alphaN = 4*Lim - angleIdx otherwise where angleIdx is the value of the indicator obtained from the bitstream. The value of angleIdx may be an integer value, and the numeric range of angleIdx is 0 to 31, inclusive.

[0215] In another example, the value of alphaN may be calculated according to one of the following formulas: alphaN= angleIdx, or alphaN = 2*Lim - angleIdx, or alphaN = angleIdx - 2*Lim, or alpha N= 4*Lim - angleIdx

[0216] In the above equation, Lim is a predefined constant value related to the number of quantized angle values. For example, if there are 32 different quantized angle values, Lim may be equal to 8 (4*Lim is equal to 32). In another example, Lim can be 4, which corresponds to a total of 16 different quantized angle values.

[0217] In one embodiment, the value of sample_dist is calculated according to the formula: sample_dist = ((2*x) - W + K)*f1(alpha) + ((2*y) - H + K))*f2(alpha) - distanceIdx*stepD*scaleStep where: f1() and f2() are functions and alpha is the input to the functions. In the example, f1() and f2() are implemented as lookup tables and the value of alpha is the index value for the lookup table. The value of scaleStep is equal to either the value of the width of the coding (decoding or encoding) block or the value of the height of the coding block. · x and y are the coordinates of said sample relative to the top left sample of the coding block. K is an integer offset value. In the example, the value of K is 1.

[0218] In one embodiment, functions f1() and f2() are implemented as lookup tables. In examples, functions f1() and f2() represent gradual, cumulative changes in the value of sample_dist for varying x and y values. In some examples, f1(index) represents the value of sample_dist changed by a one-unit increment in the value of x (the unit may be an increment equal to 1), while f2(index) represents the value of sample_dist changed by a one-unit increment in the value of y. The value of index may be obtained from the value of an indicator in the bitstream.

[0219] In another embodiment, the value of sample_dist is calculated using the formula: sample_dist = ((2*x) - W + K)*f(dispIdxN) + ((2*y) - H + K))*f(dispIdxS) - distanceIdx*stepD*scaleStep where: f() is a function, and in the example, the function f() is implemented as a lookup table. · dispIdxN or dispIdxS is an index value obtained from the bitstream or calculated based on the value of the indicator in the bitstream. The value of scaleStep is equal to either the value of the width of the coding (decoding or encoding) block or the value of the height of the coding block. · x and y are the coordinates of said sample relative to the top left sample of the coding block. K is an integer offset value. In the example, the value of K is 1.

[0220] In an embodiment, the function f() is implemented as a lookup table. The function f() represents the gradual cumulative change in the value of sample_dist for changing x and y values. In the example, f(index1) represents the value of sample_dist changed by a one-unit increase in the value of x, while f(index2) represents the value of sample_dist changed by a one-unit increase in the value of y. The values ​​of index1 and index2 are indices into the table (having integer values ​​equal to or greater than 0) that can be obtained according to the value of the indicator in the bitstream.

[0221] In the example, an implementation of the function f() is shown in Figure 14. In this example, the value of idx is an input parameter (which may be index1 or index2), and the output of the function is shown as f(idx). In the example, f() is an implementation of the cosine function using integer arithmetic, and idx (the input index value) represents the quantized angle value.

[0222] In one embodiment, the value of stepD represents a quantized distance value for the sample distance calculation.

[0223] In one embodiment, the value of stepD is obtained according to the value of whRatio and the value of angle (alpha), as shown in Figure 13. In the example, the value of stepD is: stepD = lookupTable[alphaN][whRatio], where the value of alphaN is an index value obtained from the bitstream, or the value of alphaN is calculated based on the value of the indicator obtained from the bitstream. For example, alpha can be expressed by the formula: alphaN=angleIdx if angleIdx>=0&&angleIdx<=8, or alphaN=16-angleIdx if angleIdx>8&&angleIdx<=16, or alphaN=angleIdx-16 if angleIdx>16&&angleIdx<=24, or alphaN=32-angleIdx otherwise where angleIdx is the index value obtained according to the bitstream.

[0224] In another example, alphaN= angleIdx if angleIdx >= 0 && angleIdx <=Lim, or alphaN = 2*Lim - angleIdx if angleIdx > Lim && angleIdx<= 2*Lim, or alphaN = angleIdx - 2*Lim if angleIdx > 2*Lim && angleIdx <=3*Lim, or alphaN = 4*Lim - angleIdx otherwise is.

[0225] Or, in another example, alphaN = angleIdx, or alphaN = 2*Lim - angleIdx, or alphaN = angleIdx - 2*Lim, or alphaN = 4*Lim - angleIdx is.

[0226] In the above equation, Lim is a predefined constant value related to the number of quantized angle values. For example, if there are 32 different quantized angle values, then the number Lim may be equal to 8 (4*Lim is equal to 32). In another example, Lim can be 4, which corresponds to a total of 16 different quantized angle values.

[0227] In one example, the value of sample_dist is obtained by distanceIdx*stepD*scaleStep, where distanceIdx is an index value obtained according to the bitstream, and the value of scaleStep is obtained according to either the block width value or the block height value. The result of the multiplication represents the distance of the dividing line to the center point of the coding block (with coordinates x=W / 2 and y=H / 2).

[0228] In the example, the lookup table is a predefined table. A predefined table has the following advantages: Obtaining the distance of a sample to the dividing line is usually complex and requires solving trigonometric equations, which may not be acceptable when implementing video coding standards aimed at mass-produced consumer products.

[0229] In some embodiments, the sample distances are obtained according to a lookup table (which may be predefined) that contains pre-calculated intermediate results depending on whRatio and alpha, which have already been calculated by integer arithmetic (so in the example, all stepD values ​​are integers). The intermediate results obtained using the lookup table are carefully selected for the following reasons: The lookup table contains intermediate calculation results for complex operations (calculation of trigonometric functions), thus reducing the implementation complexity. ●The size of tables (which require memory) is kept small.

[0230] In another example, the value of sample_dist is given by distanceIdx*(stepD + T)*scaleStep, where T is an offset value having an integer value. In the example, the value of T is 32.

[0231] As shown in FIG. 20 , a coding method implemented by a decoding device or an encoding device is disclosed, and the method includes:

[0232] S2001: The value of the angle parameter for the current block is obtained.

[0233] In an example, the value of the angle parameter may be obtained by parsing an index value coded in the video bitstream, or the value of the angle parameter may be determined according to a syntax value parsed from the video bitstream.

[0234] The bit stream may be obtained by a wireless or wired network. The bit stream may be transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, microwave, WIFI, Bluetooth, LTE, or 5G.

[0235] In an embodiment, a bitstream is a sequence of bits, e.g., in the form of a network abstraction layer (NAL) unit stream or byte stream, that forms a representation of a sequence of access units (AUs) that form one or more coded video sequences (CVSs).

[0236] In some embodiments, for the decoding process, the decoder side reads the bitstream and derives the decoded pictures from the bitstream, and for encoding, the encoder side generates the bitstream.

[0237] Typically, a bitstream contains syntax elements that are organized by syntax structures. Syntax element: An element of data that is represented within a bitstream. Syntax structure: Zero or more syntax elements that occur together in a bitstream in a specified order.

[0238] In a particular example, the format of a bitstream defines the relationship between a Network Abstraction Layer (NAL) unit stream and a byte stream, and either a Network Abstraction Layer (NAL) unit stream or a byte stream is referred to as a bitstream.

[0239] A bitstream can be, for example, in one of two formats: a NAL unit stream format or a byte stream format. The NAL unit stream format is conceptually the more "basic" type. The NAL unit stream format contains a sequence of syntax structures called NAL units. This sequence is ordered in decoding order. There are constraints imposed on the decoding order (and content) of the NAL units in a NAL unit stream.

[0240] The format of the byte stream may be constructed from the format of the NAL unit stream by ordering the NAL units in decoding order and prefixing each NAL unit with a start code prefix and zero or more zero-valued bytes to form a stream of bytes. The format of the NAL unit stream may be extracted from the format of the byte stream by searching for the location of unique start code prefix patterns within this stream of bytes.

[0241] This section specifies an embodiment of the relationship between the source and the decoded pictures given by the bitstream.

[0242] The video source represented by the bitstream is a sequence of pictures in decoding order.

[0243] In the example, the value of the indicator for the current block is obtained according to the bitstream, and the value of the indicator is used to obtain the value of the angle parameter.

[0244] In an embodiment, the value of the indicator is used to specify the shape of the partition for the geometric partition merge mode. For example, the indicator may be merge_gpm_partition_idx[x0][y0], which specifies the shape of the partition for the geometric partition merge mode. The array indexes x0, y0 specify the position (x0, y0) of the top-left luma sample of the considered coding block relative to the top-left luma sample of the picture.

[0245] Typically, the value of merge_gpm_partition_idx[ x0 ][ y0 ] is decoded from the bitstream. In the example, the numeric range of merge_gpm_partition_idx[ ][ ] is from 0 to 63, inclusive. In the example, the decoding process for merge_gpm_partition_idx[ ][ ] is "bypass."

[0246] When merge_gpm_partition_idx[ x0 ][ y0 ] is not present, merge_gpm_partition_idx[ x0 ][ y0 ] is inferred to be equal to 0.

[0247] The value of the angle parameter for the current block is obtained according to the value of the indicator and a predefined look-up table.

[0248] In an embodiment, the angle variable angleIdx (angle parameter) and distance variable distanceIdx of a partition in the geometric partitioning mode are set according to the value of merge_gpm_partition_idx[ xCb ][ yCb ] (indicator) as specified in the table below. In implementation, this relationship may be implemented according to Table 1 or by a function.

[0249] [Table 5]

[0250] S2002: The width value and the height value of the current block are obtained.

[0251] In an example, W and H are the width and height of the current block expressed in number of samples, and W and H are parsed from the bitstream. In an example, a coding block having a width and height both equal to 8 is a square block containing 64 samples. In another example, W and H are the width and height of the current block expressed in number of luma samples.

[0252] S2003: Calculate the ratio between the width value and the height value.

[0253] In an embodiment, the value of whRatio represents the ratio between the width and height of the current coding block.

[0254] In the example, whRatio = H / W or whRatio = W / H.

[0255] In another example, two variables, nCbW and nCbH, specify the width and height of the current coding block, and the variable cIdx specifies the color component index.

[0256] The variables nW, nH, and whRatio are derived as follows: nW = ( cIdx == 0 ) ? nCbW : nCbW * SubWidthC nH = ( cIdx == 0 ) ? nCbH : nCbH * SubHeightC whRatio = nH / nW

[0257] In the example, the variables SubWidthC and SubHeightC are defined in Table 2 according to the sampling structure of the chroma format specified by sps_chroma_format_idc and sps_separate_colour_plane_flag.

[0258] [Table 6]

[0259] In monochrome sampling, there is only one sample array, which is nominally considered the luma array. In 4:2:0 sampling, each of the two chroma arrays has half the height and half the width of the luma array. In 4:2:2 sampling, each of the two chroma arrays has the same height and half the width of the luma array. For 4:4:4 sampling, depending on the value of sps_separate_colour_plane_flag the following applies: - If sps_separate_colour_plane_flag is equal to 0, each of the two chroma arrays has the same height and width as the luma array. - Otherwise (sps_separate_colour_plane_flag equals 1), the three colour planes are treated separately as a monochrome sampled picture.

[0260] S2004: Calculate the distance value of the sample for the sample of the current block according to the angle parameter value and the ratio value.

[0261] In an embodiment, step S2004 includes:

[0262] Step 1: Get the value of shiftHor according to the lookup table, the value of alpha, and the value of whRatio.

[0263] In an example, the value of alpha (alphaN or angleIdx) and the value of whRatio are used as index values ​​for a lookup table. The value of shiftHor can also be obtained according to a function, where the value of alpha (alphaN or angleIdx) and the value of whRatio are input to the function and the value of shiftHor is the output of the function. In an example, the result of the function is similar to or the same as the lookup table. In an example, the value of shiftHor represents a quantization step size for the sample distance calculation process.

[0264] In another example, the function may be represented by shiftHor = ( angleIdx % 16 == 8 || ( angleIdx % 16 != 0 && whRatio > 0 ) ) ? 0 : 1.

[0265] Step 2: The value of sample_dist is calculated according to the value of shiftHor.

[0266] In the example, to calculate the sample distance (sample_dist), first the variables offsetX and offsetY are derived as follows: If shiftHor is equal to 0, the following applies: offsetX = ( -nW ) >> 1, offsetY = ( ( =nH ) >> 1 ) + ( angleIdx < 16 ? ( distanceIdx * nH ) >> 3 : -( ( distanceIdx * nH ) >> 3 ) ) Otherwise (shiftHor is equal to 1), the following applies: offsetX = ( ( -nW ) >> 1 ) + ( angleIdx < 16 ? ( distanceIdx * nW ) >> 3 : -( ( distanceIdx * nW ) >> 3 ) ) offsetY = ( -nH ) >> 1 The variables xL and yL are derived as follows: xL = ( cIdx == 0 ) ? x : x * SubWidthC yL = ( cIdx == 0 ) ? y : y * SubHeightC sample_dist = ( ( ( xL + offsetX ) << 1 ) + 1 ) * disLut[ displacementX ] + ( ( ( yL + offsetY ) << 1 ) + 1 ) ) * disLut[ displacementY ]

[0267] The variables displacementX and displacementY are derived as follows: hwRatio = cbHeight / cbWidth displacementX = angleIdx displacementY = (angleIdx + 8) % 32

[0268] The sequence disLut is defined in Table 3.

[0269] In some embodiments, according to the geometric model, the samples of a coding block are considered to be in two sub-blocks. Sub-block A or sub-block B may contain some (but not all) of the samples of the current coding block. Sub-block A or sub-block B may be represented by the sign of sample_dist of each sample. sample_dist may be obtained according to the examples and embodiments of other paragraphs.

[0270] S2005: Obtain a predicted value for the sample of the current block according to the distance value of the sample.

[0271] In one implementation, obtaining a predicted value for a sample according to a distance value of the sample for the sample includes: Calculating two weighting factors according to the distance values ​​of the samples; obtaining a predicted value for the sample according to the first predicted value, the second predicted value, and the two weighting factors.

[0272] In one implementation, the distance value of a sample represents the horizontal or vertical or combined vertical and horizontal distance of the sample to a dividing line, which is used to divide the coding block into two sub-blocks.

[0273] In one example, the calculated sample_dist is used to calculate a weighting factor, which is used for combining the first predicted value and the second predicted value corresponding to the sample. In the example, the weighting factors are denoted as sampleWeight1 and sampleWeight2, which refer to the weight corresponding to the first predicted value and the weight corresponding to the second predicted value.

[0274] In one example, the weighting factor is a function of: weightIdxL = partFlip ? 32 + sample_dist : 32 - sample_dist wValue = Clip3( 0, 8, ( weightIdxL + 4 ) >> 3 ) It is calculated by:

[0275] In this example, wValue is sampleWeight1, and 8 - wValue is sampleWeight2. The variable partFlip is determined according to the value of angleIdx. In the example, partFlip = ( angleIdx >= 13 && angleIdx <= 27 ) ? 0 : 1, or partFlip = ( angleIdx >= 13 && angleIdx <= 27 ) ? 1 : 0.

[0276] In one example, a combined value of a predicted sample at sample coordinate (x, y) is calculated according to a first predicted value at coordinate (x, y), a second predicted value at coordinate (x, y), sampleWeight1, and sampleWeight2.

[0277] In the example, the predicted sample values ​​are derived as follows: pbSamples[ x ][ y ] = Clip3( 0, ( 1 << BitDepth ) - 1, ( predSamplesLA[ x ][ y ] * wValue + predSamplesLB[ x ][ y ] * ( 8 - wValue ) + offset1 ) >> shift1 )

[0278] In the formula, bitDepth represents the bit depth of the samples, the variable shift1 is obtained according to bitDepth, in the example, shift1 = Max(5, 17 - BitDepth), the variable offset1 is obtained according to shift1, in the example, offset1 = 1 << (shift1 - 1), and predSamplesLA and predSamplesLB are two (nCbW) x (nCbH) arrays.

[0279] 21 , an apparatus 2100 is disclosed. The apparatus 2100 includes: a parameter obtaining module 2101 configured to obtain an angle parameter value for a current block, the parameter obtaining module 2101 being further configured to obtain a width value of the current block and a height value of the current block; a ratio calculation module 2102 configured to calculate a ratio value between the width value and the height value; a sample distance calculation module 2103 configured to calculate sample distance values ​​for samples of the current block according to the angle parameter value and the ratio value; and a prediction module 2104 configured to obtain predicted values ​​for samples of the current block according to the sample distance values.

[0280] The method according to the embodiment of the present invention may be performed by the apparatus 2100. Further features and implementation forms of the above method correspond to the features and implementation forms of the apparatus 2100.

[0281] Example 1. A method of coding implemented by a decoding or encoding device, comprising: obtaining a value of an angle parameter for the current block; obtaining a current block width value and a current block height value; calculating a ratio value between the width value and the height value; Obtaining a first value according to the value of the angle parameter and the value of the ratio; calculating a distance value of the sample for the sample of the current block according to the first value; obtaining predicted values ​​for the samples of the current block according to the distance values ​​of the samples.

[0282] Example 2. The method of Example 1, wherein the first value is obtained according to a predefined lookup table, and the value of the angle parameter and the value of the ratio are used as index values ​​for the predefined lookup table.

[0283] Example 3. The method of example 2, wherein the predefined lookup table contains 9 different angle values ​​(0 to 8).

[0284] Example 4. The method of example 2, wherein the predefined lookup table includes five different angle values ​​(0 to 4).

[0285] Example 5. The method of any one of Examples 2 to 4, wherein the predefined lookup table includes four different ratio values ​​(0 to 3).

[0286] Example 6. The method of any one of Examples 2 to 4, wherein the predefined lookup table includes five different ratio values ​​(0 to 4).

[0287] Example 7. The method of any one of Examples 2 to 4, wherein the predefined lookup table includes three different ratio values ​​(0 to 2).

[0288] Example 8. The method of any one of Examples 2 to 7, wherein the predefined lookup table includes a first value corresponding to each combination of an angle value and a ratio value.

[0289] Example 9. The step of calculating the distance value of the sample relative to the sample of the current block according to the first value, The method of any one of Examples 1 to 8, comprising calculating a distance value of the sample for the current block of samples according to the first value and the value of the angle parameter.

[0290] Example 10. The value of the ratio is whRatio = (wIdx >= hIdx) ? wIdx - hIdx : hIdx - wIdx where whRatio is a ratio value, W is a width value, H is a height value, the value of wIdx is equal to log2(W) - 3, and the value of hIdx is equal to log2(H) - 3.

[0291] Example 11. The value of the ratio is whRatio = (W >= H) ? W / H : H / W 10. The method of any one of Examples 1 to 9, wherein whRatio is a ratio value, W is a width value, and H is a height value.

[0292] Example 12. If the sample distance value is sample_dist = ((2*x) - W + K)*f1(alpha) + ((2*y) - H + K))*f2(alpha) - distanceIdx*stepD*scaleStep 12. The method of any one of Examples 1 to 11, wherein sample_dist is a sample distance value, f1() and f2() are functions, alpha is a parameter of value angle (in the example, f1() and f2() are implemented as lookup tables, and the value of alpha is an index value for the lookup table), the value of scaleStep is equal to either a width value or a height value, x and y are the coordinates of the sample relative to the top-left sample of the current block, and K is an integer offset value.

[0293] Example 13. If the sample distance value is sample_dist = ((2*x) - W + K)*f(dispIdxN) + ((2*y) - H + K))*f(dispIdxS) - distanceIdx*stepD*scaleStep where sample_dist is a sample distance value, f() is a function (in an example, the function f() is implemented as a lookup table), dispIdxN or dispIdxS is an index value (in an example, dispIdxN or dispIdxS is obtained from the bitstream or calculated based on the value of an indicator in the bitstream), the value of scaleStep is equal to either a width value or a height value, x and y are the coordinates of the sample relative to the top-left sample of the current block, and K is an integer offset value (in an example, the value of K is 1),

[0294] Example 14. A decoder (30) or encoder including processing circuitry for performing the method according to any one of examples 1 to 13.

[0295] Example 15. A computer program product comprising program code for performing the method according to any one of Examples 1 to 13.

[0296] Example 16. A decoder or encoder, one or more processors; a non-transitory computer-readable storage medium coupled to the processor and storing programming for execution by the processor, the programming, when executed by the processor, configuring the decoder to perform a method according to any one of Examples 1 to 13; and a decoder or encoder, including

[0297] The following is a description of the application of the encoding and decoding methods shown in the above embodiments and the systems that use them.

[0298] 18 is a block diagram showing a content supply system 3100 for realizing a content distribution service. The content supply system 3100 includes a capture device 3102, a terminal device 3106, and optionally a display 3126. The capture device 3102 communicates with the terminal device 3106 via a communication link 3104. The communication link may include the communication channel 13 described above. The communication link 3104 includes, but is not limited to, WIFI, Ethernet, cable, wireless (3G / 4G / 5G), USB, or any combination thereof.

[0299] The capture device 3102 may generate data and encode the data according to the encoding method described in the above embodiment. Alternatively, the capture device 3102 may deliver the data to a streaming server (not shown), which then encodes the data and transmits the encoded data to the terminal device 3106. The capture device 3102 may include, but is not limited to, a camera, a smartphone or smart pad, a computer or laptop, a video conferencing system, a PDA, an in-vehicle device, or any combination thereof. For example, the capture device 3102 may include the source device 12 described above. When the data includes video, a video encoder 20 included in the capture device 3102 may actually perform the video encoding process. When the data includes audio (i.e., voice), an audio encoder included in the capture device 3102 may actually perform the audio encoding process. In some practical scenarios, the capture device 3102 delivers the encoded video and audio data by multiplexing them together. In other practical scenarios, for example, in a video conferencing system, the encoded audio data and the encoded video data are not multiplexed. The capture device 3102 delivers the encoded audio data and the encoded video data separately to the terminal device 3106 .

[0300] In the content supply system 3100, the terminal device 3106 receives and plays the encoded data. The terminal device 3106 can be a device having data reception and restoration capabilities, such as a smartphone or smart pad 3108, a computer or laptop 3110, a network video recorder (NVR) / digital video recorder (DVR) 3112, a TV 3114, a set-top box (STB) 3116, a video conferencing system 3118, a video surveillance system 3120, a personal digital assistant (PDA) 3122, an in-vehicle device 3124, or any combination thereof, capable of decoding the above-mentioned encoded data. For example, the terminal device 3106 may include the above-mentioned destination device 14. When the encoded data includes video, the video decoder 30 included in the terminal device is prioritized to perform video decoding. When the encoded data includes audio, the audio decoder included in the terminal device is prioritized to perform audio decoding processing.

[0301] For terminal devices with a display, such as a smartphone or smart pad 3108, a computer or laptop 3110, a network video recorder (NVR) / digital video recorder (DVR) 3112, a TV 3114, a personal digital assistant (PDA), or an in-vehicle device 3124, the terminal device can provide the decoded data to its display. For terminal devices without a display, such as an STB 3116, a video conferencing system 3118, or a video surveillance system 3120, an external display 3126 is contacted to receive and show the decoded data.

[0302] When each device in this system performs encoding or decoding, the picture encoding device or picture decoding device shown in the above embodiments may be used.

[0303] 19 is a diagram illustrating an example structure of a terminal device 3106. After the terminal device 3106 receives a stream from the capture device 3102, a protocol progression unit 3202 analyzes the transmission protocol of the stream. The protocol may include, but is not limited to, Real Time Streaming Protocol (RTSP), Hypertext Transfer Protocol (HTTP), HTTP Live Streaming Protocol (HLS), MPEG-DASH, Real Time Transport Protocol (RTP), Real Time Messaging Protocol (RTMP), or any type of combination thereof.

[0304] After the protocol progression unit 3202 processes the stream, a stream file is generated. The file is output to the demultiplexing unit 3204. The demultiplexing unit 3204 can separate the multiplexed data into encoded audio data and encoded video data. As mentioned above, in some practical scenarios, for example, in a video conference system, the encoded audio data and encoded video data are not multiplexed. In this situation, the encoded data is sent to the video decoder 3206 and the audio decoder 3208 without passing through the demultiplexing unit 3204.

[0305] The demultiplexing process generates a video elementary stream (ES), an audio ES, and optionally subtitles. A video decoder 3206, which includes the video decoder 30 described in the above embodiment, decodes the video ES using the decoding method shown in the above embodiment to generate video frames and supplies this data to a synchronization unit 3212. An audio decoder 3208 decodes the audio ES to generate audio frames and supplies this data to the synchronization unit 3212. Alternatively, the video frames may be stored in a buffer (not shown in FIG. 19) before being supplied to the synchronization unit 3212. Similarly, the audio frames may be stored in a buffer (not shown in FIG. 19) before being supplied to the synchronization unit 3212.

[0306] The synchronization unit 3212 synchronizes the video and audio frames and provides the video / audio to a video / audio display 3214. For example, the synchronization unit 3212 synchronizes the presentation of video and audio information. The information may be coded in a syntax that uses timestamps for the presentation of the coded audio and visual data as well as for the delivery of the data stream itself.

[0307] If subtitles are included in the stream, the subtitle decoder 3210 decodes the subtitles, synchronizes the subtitles with the video and audio frames, and provides the video / audio / subtitles to the video / audio / subtitle display 3216.

[0308] The present invention is not limited to the above-mentioned system, and either the picture encoding device or the picture decoding device of the above-mentioned embodiments may be incorporated into other systems, for example, a system in an automobile.

[0309] Mathematical Operators The mathematical operators used in this application are similar to those used in the C programming language. However, the results of integer division and arithmetic shift operations are more strictly defined, and additional operations such as exponentiation and division of real values ​​are defined. The numbering and counting rules generally start from 0; for example, "first" is equivalent to number 0, "second" is equivalent to number 1, and so on.

[0310] Arithmetic operators The following arithmetic operators are defined as follows: + Addition - subtraction (as a two-argument operator) or negation (as a unary prefix operator) * Multiplication, including matrix multiplication x y Exponentiation. Specifies x to the yth power. In other contexts, such notation is used to write superscripts that are not intended to be interpreted as powers. / Integer division with result truncation towards zero. For example, 7 / 4 and -7 / -4 round down to 1, and -7 / 4 and 7 / -4 round down to -1. ÷ Used to represent division in mathematical equations where truncation or rounding is not intended.

number

number

[0311] Logical operators The following logical operators are defined as follows: x && y The Boolean logic "intersection" of x and y x || y Boolean logic "union" of x and y Boolean logic "negation" x ? y : zIf x is true or not equal to 0, evaluates to the value y, otherwise evaluates to the value z.

[0312] Relational operators The following relational operators are defined as follows: > Greater than >= Greater than or equal to < Less than <= Less than or equal to == Equal to != Not equal to

[0313] When a relational operator is applied to a syntax element or variable that has been assigned the value "na" (not applicable), the value "na" is treated as a distinct value for the syntax element or variable. The value "na" is not considered equal to any other value.

[0314] Bitwise Operators The following bitwise operators are defined as follows: & Bitwise "and". When operating on integer arguments, operates on the two's complement representation of the integer value. When operating on a binary argument that contains fewer bits than another argument, the shorter argument is extended by adding more significant bits equal to 0. Bitwise "logical or". When operating on integer arguments, operates on the two's complement representation of the integer values. When operating on a binary argument that contains fewer bits than another argument, the shorter argument is extended by adding more significant bits equal to 0. ^ Bitwise "exclusive or". When operating on integer arguments, operates on the two's complement representation of the integer value. When operating on a binary argument that contains fewer bits than another argument, the shorter argument is extended by adding more significant bits equal to 0. x >> y Arithmetic right shift of the two's complement representation of an integer x by y bits in binary. This function is defined only for non-negative integer values of y. The bit shifted into the most significant bit (MSB) as a result of the right shift has the same value as the MSB of x before the shift operation. x << y Arithmetic left shift of the two's complement representation of an integer x by y bits in binary. This function is defined only for non-negative integer values of y. The bit shifted into the least significant bit (LSB) as a result of the left shift has a value equal to 0.

[0315] Assignment operator The following arithmetic operators are defined as follows. = Assignment operator ++ Increment, i.e., x++ is equivalent to x = x + 1, and when used as an array index, the value of the variable is evaluated before the increment operation. -- Decrement, i.e., x-- is equivalent to x = x - 1, and when used as an array index, the value of the variable is evaluated before the decrement operation. += Increment by the specified amount, i.e., x += 3 is equivalent to x = x + 3, and x += (-3) is equivalent to x = x + (-3). -= Decrement by the specified amount, i.e., x -= 3 is equivalent to x = x - 3, and x -= (-3) is equivalent to x = x - (-3).

[0316] Range notation The following notations are used to specify a range of values. x = y..z x takes integer values from y to z, including y and z, assuming x, y, and z are integer values and z is greater than y.

[0317] Mathematical functions The following mathematical functions are defined. [Number] Asin( x ) The trigonometric arc sine function, operating on an argument x in the range of -1.0 to 1.0, inclusive, and with an output value in radians ranging from -π÷2 to π÷2, inclusive. Atan(x) The trigonometric arctangent function that operates on the argument x and has an output value in the range -π÷2 to π÷2, inclusive, in radians.

number

number

number

number

number

number

number

[0318] Operation precedence When precedence within an expression is not made explicit using parentheses, the following rules apply: - Operations with higher precedence are evaluated before any operations with lower precedence. - Operations of equal precedence are evaluated in order from left to right.

[0319] The table below specifies the precedence of operations from highest to lowest, with higher positions in the table indicating higher precedence.

[0320] With respect to operators that are also used in the C programming language, the precedence used herein is the same as that used in the C programming language.

[0321] [Table 7]

[0322] Text description of logical operations In the text, in the following form: if( condition 0 ) Statement 0 else if( condition1 ) Statement 1 ... else / * Comment giving information about remaining conditions * / Statement n A logical statement mathematically written in the form: may be written as follows: As follows... / ...the following applies: - If condition 0, then statement 0 - Otherwise, if condition 1, then statement 1 - ... - otherwise (comment conveying information about the remaining conditions), statement n

[0323] Each "if ..., otherwise ..., then ..., otherwise" statement in the text is introduced by "as follows ..." or "...the following applies" immediately followed by "if ..., then ...". The final condition of an "if ..., otherwise ..., then ..., otherwise ..." is always "otherwise ...". Alternately inserted "if ..., otherwise ..., then ..., otherwise ..." statements can be identified by matching the "as follows ..." or "...the following applies" with the closing "otherwise ...".

[0324] In the text, in the following form: if( condition0a && condition0b ) Statement 0 else if( condition 1a || condition 1b ) Statement 1 ... else Statement n A logical statement mathematically written in the form: may be written as follows: As follows... / ...the following applies: - Statement 0 if all of the following conditions are true: - Condition 0a - Condition 0b - Otherwise, if one or more of the following conditions are true, then statement 1 - Condition 1a - Condition 1b - ... - otherwise, statement n

[0325] In the text, in the following form: if( condition 0 ) Statement 0 if( condition1 ) Statement 1 A logical statement mathematically written in the form: may be written as follows: If condition 0, then statement 0 If condition 1, then statement 1

[0326] It should be noted that, although embodiments of the present invention have been described primarily in the context of video coding, embodiments of coding system 10, encoder 20, and decoder 30 (and correspondingly, system 10), as well as other embodiments described herein, may also be configured for processing or coding of still pictures, i.e., processing or coding of individual pictures independent of any preceding or subsequent pictures, similar to video coding. Generally, when picture processing coding is limited to a single picture 17, only inter prediction units 244 (encoder) and 344 (decoder) may not be available. All other functions (also called tools or technologies) of the video encoder 20 and the video decoder 30, such as residual calculation 204 / 304, transform 206, quantization 208, inverse quantization 210 / 310, (inverse) transform 212 / 312, partitioning 262 / 362, intra prediction 254 / 354, and / or loop filter 220, 320, and entropy coding 270, and entropy decoding 304, may be used equally for processing still pictures.

[0327] For example, embodiments of the encoder 20 and decoder 30 and the functionality described herein in connection with, for example, the encoder 20 and decoder 30 may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on a computer-readable medium or transmitted over a communication medium as one or more instructions or code and executed by a hardware-based processing unit. A computer-readable medium may include a computer-readable storage medium, which corresponds to a tangible medium such as a data storage medium, or a communication medium, which includes any medium that facilitates transfer of a computer program from one place to another, for example via a communication protocol. Thus, generally, a computer-readable medium may correspond to (1) a tangible computer-readable storage medium that is non-transitory or (2) a communication medium such as a signal or carrier wave. A data storage medium may be any available medium that can be accessed by one or more computers or one or more processors to retrieve instructions, code, and / or data structures for implementing the techniques described in this disclosure. A computer program product may include a computer-readable medium.

[0328] By way of example, and not limitation, such computer-readable storage media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer. Also, any connection is properly termed a computer-readable medium. For example, if instructions are transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio wave, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio wave, and microwave are included within the definition of medium. However, it should be understood that computer-readable storage media and data storage media do not include connections, carrier waves, signals, or other transitory media, but instead cover non-transitory, tangible storage media. As used herein, disk and disc include compact discs (CDs), laser discs, optical discs, digital versatile discs (DVDs), floppy disks, and Blu-ray discs, where disks typically reproduce data magnetically while discs reproduce data optically using a laser. Combinations of the above should also be included within the scope of computer-readable media.

[0329] The instructions may be executed by one or more processors, such as one or more digital signal processors (DSPs), general-purpose microprocessors, application-specific integrated circuits (ASICs), field-programmable logic arrays (FPGAs), or other equivalent integrated or discrete logic circuitry. Accordingly, the term "processor," as used herein, may refer to any of the above structures or any other structure suitable for implementing the techniques described herein. Additionally, in some aspects, the functionality described herein may be provided in dedicated hardware and / or software modules configured for encoding and decoding, or incorporated into a combined codec. Also, the techniques may be implemented entirely in one or more circuits or logic elements.

[0330] The techniques of this disclosure may be implemented in a wide variety of devices or apparatuses, including a wireless handset, an integrated circuit (IC), or a set of ICs (e.g., a chipset). Various components, modules, or units are described in this disclosure to highlight aspects of the functionality of a device configured to perform the disclosed techniques, but do not necessarily require realization by different hardware units. Rather, as noted above, the various units may be combined in a codec hardware unit or provided by a collection of interoperable hardware units including one or more processors as described above in conjunction with suitable software and / or firmware. [Explanation of symbols]

[0331] 10 Video coding system, coding system 12 Source Device 13 Encoded picture data, communication channel 14 Destination Device 16 Picture Source 17 Picture, Picture Data, Raw Picture, Raw Picture Data, Monochrome Picture, Color Picture, Current Picture 18 Preprocessor, preprocessing unit, picture preprocessor 19 Preprocessed Picture, Preprocessed Picture Data 20 Video Encoder, Encoder 21 Encoded picture data, encoded bitstream 22 Communication interface, communication unit 28 Communication interface, communication unit 30 decoder, video decoder 31 Decoded Picture Data, Decoded Picture 32 Post-processor, post-processing unit 33 Post-processed picture data, post-processed picture 34 Display Devices 46 Processing Circuit 100 Video Encoder 201 Input, input interface 203 Picture Block, Original Block, Current Block, Segmented Block, Current Picture Block 204 Residual Calculation Unit, Residual Calculation 205 Residual Block, Residual 206 Conversion Processing Unit, Conversion 207 Conversion Factor 208 Quantization Unit, Quantization 209 Quantized Coefficients, Quantized Transform Coefficients, Quantized Residual Coefficients 210 Inverse quantization unit, inverse quantization 211 Dequantized coefficients, dequantized residual coefficients 212 Inverse Transform Processing Unit, (Inverse) Transform 213 Reconstructed residual block, dequantized coefficients, transform block 214 Reconstruction Unit, Adder, Summer 215 reconstructed blocks 216 buffers 220 Loop filter unit, loop filter 221 filtered blocks, filtered reconstructed blocks 230 Decoded Picture Buffer (DPB) 231 decoded pictures 244 Inter Prediction Units 254 Intra prediction unit, Inter prediction unit, Intra prediction 260 Mode Selection Unit 262 Division Unit, Division 265 prediction block, predictor 266 Syntax Elements 270 Entropy Coding Unit, Entropy Coding 272 Output, Output Interface 304 Entropy Decoding Unit, Residual Calculation, Entropy Decoding 309 Quantized Coefficients 310 Inverse Quantization Unit, Inverse Quantization 311 Dequantized Coefficients, Transform Coefficients 312 Inverse Transform Processing Unit, (inverse) transformation, output 313 Reconstructed Residual Blocks 314 Reconstruction Unit, Summer, Adder 315 reconstructed blocks 320 Loop filter, loop filter unit, loop filtering unit 321 filtered blocks, decoded video blocks 330 Decoded Picture Buffer (DPB) 331 decoded pictures 344 Inter Prediction Unit 354 Intra prediction unit, Intra prediction 360 Mode Selection Unit 362 Division 365 predicted blocks 400 Video Coding Device 410 Incoming port, input port 420 Receiver Unit (Rx) 430 Processor, Logic Unit, Central Processing Unit (CPU) 440 Transmitter Unit (Tx) 450 outgoing and outgoing ports 460 memory 470 Coding Module 500 devices 502 processor 504 memory 506 Data 508 Operating Systems 510 Application Program 512 Bus 514 Secondary Storage 518 Display 1210 Angle alpha, angle parameter alpha 1230 distance 1250 Dividing Line 2100 equipment 2101 Parameter Acquisition Module 2102 Ratio Calculation Module 2103 Sample Distance Calculation Module 2104 Prediction Module 3100 Contents Supply System 3102 Capture Device 3104 Communication Links 3106 Terminal Device 3108 Smartphones, smart pads 3110 Computers, Laptops 3112 Network Video Recorder (NVR) / Digital Video Recorder (DVR) 3114 TV 3116 Set-top box (STB) 3118 Video Conference System 3120 Video Surveillance System 3122 Personal Digital Assistant (PDA) 3124 In-Vehicle Devices 3126 Display 3202 Protocol Progression Unit 3204 Demultiplexing Unit 3206 Video Decoder 3208 Audio Decoder 3210 Subtitle Decoder 3212 Synchronous Unit 3214 Video / Audio Display 3216 Video / Audio / Subtitle Display

Claims

1. 1. A method of coding performed by a coding device, comprising: obtaining an indicator; obtaining a value of an angle parameter for a current block according to said indicator; obtaining a width value of the current block and a height value of the current block; checking whether the value of the height of the current block is greater than or equal to the value of the width of the current block; calculating a distance value of a sample relative to the samples of the current block according to the value of the angle parameter and the result of the examining step; obtaining a predicted value for the sample of the current block according to the distance value of the sample; encoding said indicator into a bitstream; A method comprising:

2. said step of calculating a distance value of a sample relative to a sample of said current block according to said value of said angle parameter and the result of said examining step, obtaining a first value according to the value of the angle parameter and a result of the examining step; calculating a distance value of the sample relative to the sample of the current block according to the first value; 2. The method of claim 1, comprising:

3. said step of calculating distance values ​​of said samples relative to said samples of said current block according to said first values, The method of claim 2 , comprising calculating a distance value of the sample relative to the sample of the current block according to the first value and the value of the angle parameter.

4. said step of calculating distance values ​​of said samples relative to said samples of said current block according to said first values, 3. The method of claim 2, further comprising: calculating a distance value of the sample relative to the sample of the current block according to the first value, the value of the angle parameter, a distance index value, the value of the width, and the value of the height.

5. 5. The method of claim 1, wherein the distance value of the sample represents the horizontal or vertical or combined vertical and horizontal distance of the sample to a dividing line, the dividing line being used to divide a coding block into two sub-blocks.

6. said step of obtaining a predicted value for said sample of said current block in response to a distance value of said sample, calculating two weighting factors according to the distance values ​​of the samples; obtaining the predicted value for the sample of the current block according to the first predicted value, the second predicted value, and the two weighting factors; 6. The method of any one of claims 1 to 5, comprising:

7. A computer program comprising program code for carrying out the method according to any one of claims 1 to 6.

8. 1. An encoder comprising: one or more processors; a non-transitory computer-readable storage medium coupled to the processor and storing a bitstream for execution by the processor, the bitstream configuring the encoder to perform the method of any one of claims 1 to 6 when executed by the processor; and Including, an encoder.

9. 1. A device for storing and decoding video or image bitstreams, comprising: a communications interface, a processor, a storage medium, a parameter retrieval module, a sample distance calculation module, and a prediction module; wherein the communications interface is configured to receive and / or transmit bitstreams; the storage medium is configured to store the bitstreams; the processor decodes the bitstream to obtain an indicator; the parameter retrieval module is configured to use the indicator to retrieve a value of an angle parameter for a current block; the sample distance calculation module is configured to calculate sample distance values ​​for samples of the current block using the value of the angle parameter and a result of checking, wherein the result of checking is whether a height value of the current block is greater than or equal to a width value of the current block; and the prediction module is configured to use the sample distance values ​​to retrieve predicted values ​​for the samples of the current block.

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