Decoder and corresponding method for signaling picture partition information for slicing.

Abstract

To provide a device and a method for coding and decoding which signal picture partition information for slice.SOLUTION: A method for decoding includes the steps of: acquiring a bit stream of a current picture; acquiring the number of tiles in a tile row of the current picture; acquiring the value of the address of the current slice in the current picture; acquiring the value of a tileX which shows a horizontal address in a tile index according to the value of the address of the current slice; and parsing the indication value of a slice width from a bit stream of the current picture when the differential value between the number of tiles in the tile row of the current picture and the value of the tileX is not equal to a first threshold value. The first threshold value is an integer value and the value may be 0, 1, 2, for example.SELECTED DRAWING: Figure 13

Description

[Technical Field]

[0001] [Cross-references to related applications] This application claims priority from PCT / EP2020 / 055220 at the World Intellectual Property Organization. The entirety of the disclosure of the above patent application is incorporated by reference.

[0002] [Technical field] Embodiments of this application relate in general to the field of picture processing, and more specifically to signaling picture partition information for slicing. [Background technology]

[0003] Video coding (video encoding and / or 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 like video chat, video conferencing, DVD and Blu-ray discs, video content acquisition and editing systems, and camcorders in security applications.

[0004] Even relatively short videos can require a considerable amount of video data to depict, which can cause difficulties when data is streamed or transmitted across communication networks with limited bandwidth. Therefore, video data is generally compressed before being transmitted across modern telecommunications networks. Video size can also be a concern when video is stored on storage devices, as memory resources can be limited. Video compression devices often use software and / or hardware at the source to encode video data before transmission or storage, thereby reducing the amount of data required to represent the digital video image. The compressed data is then received at the destination by a video decompression device that decodes the video data. Due to limited network resources and the ever-increasing demand for higher video quality, improved compression and decompression techniques that improve the compression ratio with little to no sacrifice of picture quality are desirable. [Overview of the initiative]

[0005] Embodiments of this application provide apparatus and methods for encoding and decoding according to independent claims.

[0006] The above and other objectives are achieved by the subject matter of the independent claim. Further forms of implementation are evident from the dependent claims, detailed description and drawings.

[0007] A first aspect of the present invention provides a coding method implemented by a decoding device, the method comprising: obtaining a bitstream of the current picture; obtaining the number of tiles in a tile row of the current picture; obtaining the address value of a slice of the current picture; obtaining the value of tileX according to the address value of the slice; and, if the difference between the number of tiles in a tile row of the current picture and the value of tileX is not equal to a first threshold, parsing an indicator value of the slice width from the bitstream of the current picture.

[0008] According to embodiments of the present invention, a signaling scheme is disclosed in which only at least two tile rows exist, in which case a syntax element of the slice width is signaled. Thus, bitstream utilization and decoding efficiency are improved.

[0009] The first threshold is an integer value, and the first threshold can be 0, 1, 2, ...

[0010] It can be understood that the number of tiles in a tile row is equivalent to the number of tiles in a tile column.

[0011] In one implementation, the method further includes the step of setting the slice width indicator to a default value when the difference between the number of tiles in the current picture tile row and the value of tileX is equal to a first threshold. The default value is an integer value, and in one example, the default value may be 0 or 1.

[0012] In one implementation, the default value indicates that the slice width contains one tile column.

[0013] In one implementation, the step of obtaining the value of tileX according to the address value of the slice includes the step of obtaining the value of tileX according to the address value of the slice and the number of tiles in the tile row of the current picture.

[0014] In one implementation, the address of a slice is the index of the leftmost tile in the top row of tiles in the slice, and the tiles currently included in the picture are indexed according to the raster scan order.

[0015] In one implementation, the value of tileX is obtained according to a modulo operation between the value of the slice address and the number of tiles in the tile row of the current picture. In some examples, it can be understood that the condition "when the difference value between the number of tiles in the tile row of the current picture and the value of tileX is not equal to the first threshold" is equal to the condition "when the difference value between the number of tiles in the tile row of the current picture and the value of the modulo operation between the value of the slice address and the number of tiles in the tile row of the current picture is not equal to the first threshold". Therefore, the value of tileX is not calculated first, but is represented according to the result of the modulo operation between the value of the slice address and the number of tiles in the tile row of the current picture.

[0016] In one implementation, the value of the slice address specifies the address of the upper left coordinate of the slice in the tile index.

[0017] In one implementation, the value of tileX indicates the value of the horizontal coordinate. In one example, the value of tileX indicates the horizontal address in the tile index.

[0018] In one implementation, the method further includes the steps of obtaining the number of tiles in the tile column of the current picture, obtaining the value of tileY according to the value of the slice address, and parsing the indication value of the slice height from the bit stream of the current picture when the difference value between the number of tiles in the tile column of the current picture and the value of tileY is not equal to the second threshold. The second threshold is an integer value, and the second threshold may be 0, 1, 2,....

[0019] It can be understood that the number of tiles in the tile column has the same meaning as the number of tile rows.

[0020] In one implementation, the method further includes the step of setting the indication value of the slice height to a preset value when the difference value between the number of tiles in the tile column of the current picture and the value of tileY is equal to the second threshold.

[0021] In one implementation manner, the step of obtaining the value of tileY according to the value of the slice address includes the step of obtaining the value of tileY according to the value of the slice address and the number of tiles in the tile row of the current picture.

[0022] In one implementation manner, the value of tileY is obtained according to an integer division operation between the value of the slice address and the number of tiles in the tile row of the current picture. In one implementation manner, the value of tileY indicates the value of the vertical coordinate. In some examples, it can be understood that the condition "when the difference value between the number of tiles in the tile column of the current picture and the value of tileY is not equal to the second threshold" is equal to the condition "when the difference value between the number of tiles in the tile column of the current picture and the value obtained by the integer division operation between the value of the slice address and the number of tiles in the tile column of the current picture is not equal to the second threshold". Therefore, the value of tileY is not calculated first, but is represented according to the result of the integer division operation between the value of the slice address and the number of tiles in the tile row of the current picture. In one example, the value of tileY indicates the vertical address in the tile index.

[0023] The second aspect of the present invention provides a coding method implemented by a decoding device, and the method includes the steps of obtaining the bitstream of the current picture, obtaining the number of tiles in the tile column of the current picture, obtaining the value of the slice address of the current picture, obtaining the value of tileY according to the value of the slice address, and when the difference value between the number of tiles in the tile column of the current picture and the value of tileY is not equal to the second threshold, parsing the indication value of the slice height from the bitstream of the current picture.

[0024] The second threshold is an integer value, and the second threshold may be 0, 1, 2,...

[0025] It can be understood that the number of tiles in the tile column has the same meaning as the number of tile rows.

[0026] In one implementation, the method further includes the step of setting the slice height indicator to a preset value when the difference between the number of tiles in the current picture's tile column and the value of tileY is equal to a second threshold. The default value is an integer, and in one example, the default value may be 0 or 1.

[0027] In one implementation, the default value indicates that the slice height contains one tile row.

[0028] In one implementation, the step of obtaining the value of tileY according to the address value of the slice is: The current step is to get the number of tiles in the picture tile row, The steps include obtaining the value of tileY according to the slice address and the number of tiles in the current picture's tile row, and Includes.

[0029] In one implementation, the value of tileY represents the vertical coordinate value. In one example, the value of tileY represents the vertical address in the tile index.

[0030] In one implementation, the address of a slice is the index of the leftmost tile in the top row of tiles in the slice, and the tiles currently included in the picture are indexed according to the raster scan order.

[0031] In one implementation, the value of tileY is obtained by performing an integer division operation between the slice address and the number of tiles in the current picture's tile row.

[0032] In the one-implementation method, the slice address value specifies the address of the top-left coordinate of the slice in the tile index.

[0033] One implementation further includes the steps of obtaining the number of tiles in the current picture's tile row, obtaining the value of tileX according to the slice address value, and, if the difference between the number of tiles in the current picture's tile row and the value of tileX is not equal to a first threshold, parsing an indicator value of the slice width from the current picture's bitstream. The first threshold is an integer value and may be 0, 1, 2...

[0034] It can be understood that the number of tiles in a tile row is equivalent to the number of tiles in a tile column.

[0035] In one implementation, the method further includes the step of setting the slice width indicator to a default value when the difference between the number of tiles in the current picture tile row and the value of tileX is equal to a first threshold. The default value is an integer value, and in one example, the default value may be 0 or 1.

[0036] In one implementation, the default value indicates that the slice width contains one tile column.

[0037] In one implementation, the step of obtaining the value of tileX according to the address value of the slice includes the step of obtaining the value of tileX according to the address value of the slice and the number of tiles in the tile row of the current picture.

[0038] In one implementation, the address of a slice is the index of the leftmost tile in the top row of tiles in the slice, and the tiles currently included in the picture are indexed according to the raster scan order.

[0039] In one implementation, the value of tileX is obtained according to a modulo operation between the slice address and the number of tiles in the current picture's tile row. In some examples, the condition "when the difference between the number of tiles in the current picture's tile row and the value of tileX is not equal to a first threshold" can be understood as being equivalent to "when the difference between the number of tiles in the current picture's tile row and the value of the modulo operation between the slice address and the number of tiles in the current picture's tile row is not equal to a first threshold." Therefore, the value of tileX is not calculated first, but is expressed according to the result of the modulo operation between the slice address and the number of tiles in the current picture's tile row.

[0040] In the one-implementation method, the slice address value specifies the address of the top-left coordinate of the slice in the tile index.

[0041] In one implementation, the value of tileX represents the horizontal coordinate value.

[0042] A third aspect of the present invention provides a coding method implemented by an encoding device, the method comprising the steps of: obtaining the number of tiles in a tile row of the current picture; obtaining the address value of a slice of the current picture; obtaining the value of tileX according to the address value of the slice; and coding an indicator value of the slice width into the bitstream of the current picture when the difference between the number of tiles in a tile row of the current picture and the value of tileX is not equal to a first threshold.

[0043] According to embodiments of the present invention, a signaling scheme is disclosed in which only at least two tile rows exist, in which case a syntax element of the slice width is signaled. Thus, bitstream utilization and decoding efficiency are improved.

[0044] The first threshold is an integer value, and the first threshold can be 0, 1, 2, ...

[0045] It can be understood that the number of tiles in a tile row is equivalent to the number of tiles in a tile column.

[0046] In one implementation, the step of obtaining the value of tileX according to the address value of the slice includes the step of obtaining the value of tileX according to the address value of the slice and the number of tiles in the tile row of the current picture.

[0047] In one implementation, the address of a slice is the index of the leftmost tile in the top row of tiles in the slice, and the tiles currently included in the picture are indexed according to the raster scan order.

[0048] In one implementation, the value of tileX is obtained according to a modulo operation between the slice address and the number of tiles in the current picture's tile row. In some examples, the condition "when the difference between the number of tiles in the current picture's tile row and the value of tileX is not equal to a first threshold" can be understood as being equivalent to "when the difference between the number of tiles in the current picture's tile row and the value of the modulo operation between the slice address and the number of tiles in the current picture's tile row is not equal to a first threshold." Therefore, the value of tileX is not calculated first, but is expressed according to the result of the modulo operation between the slice address and the number of tiles in the current picture's tile row.

[0049] In the one-implementation method, the slice address value specifies the address of the top-left coordinate of the slice in the tile index.

[0050] In one implementation, the value of tileX represents the horizontal coordinate value.

[0051] One implementation further includes the steps of obtaining the number of tiles in the tile sequence of the current picture, obtaining the value of tileY according to the value of the slice address, and coding an indicator value of the slice height into the bitstream of the current picture if the difference between the number of tiles in the tile sequence of the current picture and the value of tileY is not equal to a second threshold. The second threshold is an integer value and may be 0, 1, 2...

[0052] It can be understood that the number of tiles in a tile column is equivalent to the number of tile rows.

[0053] In one implementation, the step of obtaining the value of tileY according to the address value of the slice includes the step of obtaining the value of tileY according to the address value of the slice and the number of tiles in the tile row of the current picture.

[0054] In one implementation, the value of tileY is obtained by integer division between the slice address and the number of tiles in the current picture's tile row. In one implementation, the value of tileY represents the vertical coordinate value. In some examples, the condition "when the difference between the number of tiles in the current picture's tile row and the value of tileY is not equal to a second threshold" can be understood as being equivalent to the condition "when the difference between the number of tiles in the current picture's tile row and the result of integer division between the slice address and the number of tiles in the current picture's tile row is not equal to a second threshold". Therefore, the value of tileY is not calculated first, but is expressed according to the result of integer division between the slice address and the number of tiles in the current picture's tile row.

[0055] A fourth aspect of the present invention provides a coding method implemented by an encoding device, the method comprising the steps of: obtaining the number of tiles in a tile sequence of the current picture; obtaining the address value of a slice of the current picture; obtaining the value of tileY according to the address value of the slice; and coding an indicator value of the slice height into the bitstream of the current picture when the difference between the number of tiles in a tile sequence of the current picture and the value of tileY is not equal to a second threshold.

[0056] The second threshold is an integer value, and it can be 0, 1, 2, ...

[0057] It can be understood that the number of tiles in a tile column is equivalent to the number of tile rows.

[0058] In one implementation, the step of obtaining the value of tileY according to the address value of the slice is: This includes the step of obtaining the value of tileY according to the slice address value and the number of tiles in the current picture's tile row.

[0059] In one implementation, the value of tileY represents the value of the vertical coordinate.

[0060] In one implementation, the address of a slice is the index of the leftmost tile in the top row of tiles in the slice, and the tiles currently included in the picture are indexed according to the raster scan order.

[0061] In one implementation, the value of tileY is obtained by performing an integer division operation between the slice address and the number of tiles in the current picture's tile row.

[0062] In the one-implementation method, the slice address value specifies the address of the top-left coordinate of the slice in the tile index.

[0063] One implementation further includes the steps of obtaining the number of tiles in the current picture's tile row, obtaining the value of tileX according to the slice address value, and coding an indicator value of the slice width into the current picture's bitstream if the difference between the number of tiles in the current picture's tile row and the value of tileX is not equal to a first threshold. The first threshold is an integer value and may be 0, 1, 2...

[0064] It can be understood that the number of tiles in a tile row is equivalent to the number of tiles in a tile column.

[0065] In one implementation, the step of obtaining the value of tileX according to the address value of the slice includes the step of obtaining the value of tileX according to the address value of the slice and the number of tiles in the tile row of the current picture.

[0066] In one implementation, the address of a slice is the index of the leftmost tile in the top row of tiles in the slice, and the tiles currently included in the picture are indexed according to the raster scan order.

[0067] In one implementation, the value of tileX is obtained according to a modulo operation between the slice address and the number of tiles in the current picture's tile row. In some examples, the condition "when the difference between the number of tiles in the current picture's tile row and the value of tileX is not equal to a first threshold" can be understood as being equivalent to "when the difference between the number of tiles in the current picture's tile row and the value of the modulo operation between the slice address and the number of tiles in the current picture's tile row is not equal to a first threshold." Therefore, the value of tileX is not calculated first, but is expressed according to the result of the modulo operation between the slice address and the number of tiles in the current picture's tile row.

[0068] In the one-implementation method, the slice address value specifies the address of the top-left coordinate of the slice in the tile index.

[0069] In one implementation, the value of tileX represents the horizontal coordinate value.

[0070] A fifth aspect of the present invention provides a video decoding device, the device comprising: Currently, there is an GET module configured to retrieve the bitstream of the picture, and the GET module is configured to retrieve the number of tiles in the tile row of the picture, and to retrieve the address value of the slice of the picture, A computation module configured to obtain the value of tileX according to the value of the slice address, The system includes a parsing module configured to parse a slice width instruction value from the bitstream of the current picture when the difference between the number of tiles in the current picture's tile row and the value of tileX is not equal to a first threshold.

[0071] Details of each module in the fifth aspect of the present invention may refer to the embodiments and implementations in the first aspect of the present invention described above.

[0072] A sixth aspect of the present invention provides a video decoding device, the decoding device is Currently, there is an GET module configured to obtain the bitstream of the picture, and the GET module is configured to obtain the number of tiles in the tile column of the picture and the address value of the slice of the picture, A computation module configured to obtain the value of tileY according to the value of the slice address, The system includes a parsing module configured to parse a slice height indicator value from the bitstream of the current picture when the difference between the number of tiles in the current picture's tile column and the value of tileY is not equal to a second threshold.

[0073] Details of each module in the sixth aspect of the present invention may refer to the embodiments and implementations in the second aspect of the present invention described above.

[0074] A seventh aspect of the present invention provides a video encoding device, the encoding device is Currently, there is a retrieval module configured to retrieve the number of tiles in a tile row of the picture, and the retrieval module is configured to retrieve the address value of a slice of the picture, A computation module configured to obtain the value of tileX according to the value of the slice address, When the difference between the number of tiles in the current picture's tile row and the value of tileX is not equal to the first threshold, a coding module configured to code the slice width instruction value into the current picture's bitstream and Includes.

[0075] Details of each module in the seventh aspect of the present invention may refer to the embodiments and implementations in the third aspect of the present invention described above.

[0076] An eighth aspect of the present invention provides a video encoding device, the video encoding device is Currently, there is a retrieval module configured to retrieve the number of tiles in a row of tiles in a picture, and the retrieval module is configured to retrieve the address value of a slice in the picture, A computation module configured to obtain the value of tileY according to the value of the slice address, When the difference between the number of tiles in the current picture's tile column and the value of tileY is not equal to the second threshold, a coding module configured to code the slice height instruction value into the current picture's bitstream and Includes.

[0077] Details of each module in the eighth aspect of the present invention may refer to the embodiments and implementations in the fourth aspect of the present invention described above.

[0078] A ninth aspect of the present invention provides a decoder including a processing circuit for performing a method according to any one of the first aspect, the second aspect, and implementations of the first aspect or the second aspect.

[0079] A tenth aspect of the present invention provides a decoder including a processing circuit for performing a method according to any one of the third aspect, the fourth aspect, and the implementation methods of the third aspect and the fourth aspect.

[0080] A tenth aspect of the present invention provides a computer program product including program code for performing any one of the first, second, third, and fourth aspects, and implementations of the first, second, third, and fourth aspects.

[0081] An eleventh aspect of the present invention provides a non-temporary computer-readable medium that, when executed by a computer device, holds program code that causes the computer device to execute any one of the first, second, third, and fourth aspects, and any implementation of the first, second, third, and fourth aspects.

[0082] A twelfth aspect of the present invention is: One or more processors, A non-temporary computer-readable storage medium coupled to a processor and storing a program for execution by the processor, wherein the program, when executed by the processor, configures a decoder to execute one of the following methods: a first embodiment, a second embodiment, and an implementation of the first embodiment or the second embodiment. A decoder including this is provided.

[0083] A thirteenth aspect of the present invention is: One or more processors, A non-temporary computer-readable storage medium coupled to a processor and storing a program for execution by the processor, wherein the program, when executed by the processor, configures a decoder to execute a method according to one of the third, fourth, and third, fourth implementations. An encoder including the following is provided. [Brief explanation of the drawing]

[0084] Embodiments of the present invention will be described in more detail below with reference to the attached figures and drawings. [Figure 1A] This is a block diagram showing an example of a video coding system configured to realize embodiments of the present invention. [Figure 1B] This block diagram shows another example of a video coding system configured to realize embodiments of the present invention. [Figure 2] This block diagram shows an example of a video encoder configured to realize an embodiment of the present invention. [Figure 3] This is a block diagram illustrating an exemplary structure of a video decoder configured to realize embodiments of the present invention. [Figure 4] This is a block of examples of encoding or decoding devices. [Figure 5] This is a block of other examples of encoding or decoding devices. [Figure 6] This is an example of a picture split into CTUs. [Figure 7] This is an example of a tile-based raster scan order in CTU. [Figure 8] This is an example of a picture partition. [Figure 9] This is an example of CTU address information within a picture. [Figure 10] Another example of a picture partition. [Figure 11]This is a block diagram showing an exemplary structure of a content supply system 3100 that realizes a content distribution service. [Figure 12] This is a block diagram showing the structure of an example terminal device. [Figure 13] This is a flowchart showing an embodiment of the method. [Figure 14] This is a block diagram of an apparatus embodiment.

[0085] In the following, unless otherwise explicitly specified, the same reference numeral indicates the same or at least functionally equivalent features. [Modes for carrying out the invention]

[0086] The following description refers to the accompanying drawings, which form part of this disclosure and illustrate, by example, specific embodiments of the invention or specific ways in which embodiments of the invention may be used. It is understood that embodiments of the invention may be used in other ways and may include structural or logical modifications not shown in the drawings. Accordingly, the following detailed description should not be taken as limiting, and the scope of the invention is defined by the appended claims.

[0087] For example, disclosure relating to a described method may also apply to a corresponding device or system configured to perform the method, and vice versa. For example, if one or more steps of a particular method are described, the corresponding device may include one or more units, e.g., functional units, for performing the steps of the described one or more methods, even if one or more such units are not explicitly described or shown in the drawings (e.g., one unit performs one or more steps, or multiple units each perform one or more of the steps). On the other hand, for example, if a particular device is described based on one or more units, e.g., functional units, the corresponding method may include one step for performing the function of one or more units, even if one or more such steps are not explicitly described or shown in the drawings (e.g., one step performs the function of one or more units, or multiple steps each perform one or more of the functions of the multiple units). Furthermore, it is understood that the various exemplary embodiments and / or features described herein may be combined with each other unless otherwise specified.

[0088] Typically, video coding refers to the processing of a sequence of pictures that make up a video or 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) comprises two parts: video encoding and video decoding. Video encoding is performed on the source side and typically involves processing the original video picture (e.g., by compression) to reduce the amount of data required to represent the video picture (for more efficient storage and / or transmission). Video decoding is performed on the destination side and typically involves the reverse processing compared to the encoder in order to reconstruct the video picture. Embodiments referring to “coding” a video picture (or picture in general) are understood to relate to “encoding” or “decoding” a video picture or the respective video sequence. The combination of the encoding and decoding parts is also called a codec (Coding and Decoding).

[0089] In lossless video coding, the original video picture can be reconstructed, meaning the reconstructed video picture has the same quality as the original video picture (assuming there is no transmission loss or other data loss during storage or transmission). In lossy video coding, further compression is performed, for example, by quantization, to reduce the amount of data representing the video picture, which cannot be fully reconstructed by the decoder, meaning the quality of the reconstructed video picture is lower or worse compared to the quality of the original video picture.

[0090] Several video coding standards belong to the group of “lossy hybrid video codecs” (i.e., combining spatial and temporal prediction in the sample domain with 2D transform coding to apply quantization in the transform domain). Each picture in a video sequence is typically partitioned into a set of non-overlapping blocks, and coding is typically performed at the block level. In other words, in the encoder, for example, spatial (intra-picture) prediction and / or temporal (inter-picture) prediction are used to generate predicted blocks, the predicted blocks are subtracted from the current block (the block currently being processed / to be processed) to obtain the residual block, and the residual block is transformed to quantize it in the transform domain to reduce the amount of data to be transmitted (compression), so video is typically processed, i.e., encoded, at the block (video block) level. On the other hand, in the decoder, the reverse processing compared to the encoder is applied to the encoded or compressed block to reconstruct the current block for representation. Furthermore, the encoder replicates the decoder processing loop so that both generate the same predictions (e.g., intra and inter-predictions) and / or reconstructions to process subsequent blocks, i.e., to code them.

[0091] Embodiments of the video coding system 10, video encoder 20, and video decoder 30 will be described below with reference to Figures 1 to 3.

[0092] Figure 1A is a schematic block diagram showing an exemplary coding system 10, for example, a video coding system 10 (or simply coding system 10), which may utilize the technology of the present application. The video encoder 20 (or simply encoder 20) and video decoder 30 (or simply decoder 30) of the video coding system 10 represent examples of devices that may be configured to perform the various exemplary technologies described in the present application.

[0093] As shown in Figure 1A, the coding system 10 includes a source device 12 configured to provide encoded picture data 21 to a destination device 14 for decoding, for example, encoded picture data 13.

[0094] The source device 12 includes an encoder 20 and may also include, optionally, a picture source 16, a preprocessor (or preprocessing unit) 18, for example, a picture preprocessor 18, and a communication interface or communication unit 22.

[0095] The picture source 16 may be any type of picture capture device, e.g., a camera for capturing real-world pictures, and / or any type of picture generation device, e.g., a computer graphics processor for generating computer-animated pictures, or any other type of 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). The picture source may also be any type of memory or storage for storing any of the above pictures.

[0096] In contrast to the processing performed by the preprocessor 18 and the preprocessing unit 18, the picture or picture data 17 may also be called the raw picture or raw picture data 17.

[0097] The preprocessor 18 is configured to receive (raw) picture data 17, perform preprocessing on the picture data 17, and obtain a preprocessed picture 19 or preprocessed picture data 19. The preprocessing performed by the preprocessor 18 may include, for example, cropping, color format conversion (e.g., RGB to YCbCr), color correction, or noise reduction. It is understood that the preprocessing unit 18 may be any selected component.

[0098] The video encoder 20 is configured to receive pre-processed picture data 19 and provide encoded picture data 21 (further details are described below, for example, based on Figure 2).

[0099] The communication interface 22 of the source device 12 may be configured to receive encoded picture data 21 and transmit the encoded picture data 21 (or any further processed version thereof) over the communication channel 13 to another device, for example, the destination device 14 or any other device, for storage or direct reconstruction.

[0100] The destination device 14 includes a decoder 30 (e.g., a video decoder 30), and may also include, optionally, a communication interface or communication unit 28, a post-processor 32 (or post-processing unit 32), and a display device 34.

[0101] The communication interface 28 of the destination device 14 is configured to receive encoded picture data 21 (or any further processed version thereof) from, for example, directly from the source device 12 or from any other source, for example, a storage device, for example, an encoded picture data storage device, and to provide the encoded picture data 21 to the decoder 30.

[0102] Communication interfaces 22 and 28 may be configured to transmit or receive encoded picture data 21 or encoded data 13 via a direct communication link between the source device 12 and the destination device 14, for example, via a direct wired or wireless connection, or via any type of network, for example, a wired or wireless network or a combination thereof, or any type of private and public network, or a combination thereof.

[0103] The communication interface 22 may be configured, for example, to package the encoded picture data 21 into an appropriate format, such as a packet, and / or process the encoded picture data using any type of transmit encoding or processing for transmission over a communication link or communication network.

[0104] The communication interface 28, which forms the counterpart to the communication interface 22, may be configured, for example, to receive the transmitted data and process the transmitted data using any of the corresponding types of transmission decoding or processing and / or depackaging to obtain the encoded picture data 21.

[0105] Both communication interfaces 22 and 28 may be configured as unidirectional or bidirectional communication interfaces, as indicated by the arrows in Figure 1A for the communication channel 13 pointing from source device 12 to destination device 14, for example, to send and receive messages, to set up connections, and to acknowledge and exchange any other information relating to communication links and / or data transmission, such as encoded picture data transmission.

[0106] The decoder 30 is configured to receive encoded picture data 21 and provide decoded picture data 31 or decoded picture 31 (further details are described below, for example, based on Figure 3 or Figure 5).

[0107] The post-processor 32 of the destination device 14 is configured to post-process the decoded picture data 31 (also called reconstructed picture data), for example, the decoded picture 31, to obtain post-processed picture data 33, for example, the post-processed picture 33. The post-processing performed by the post-processing unit 32 may include, for example, color format conversion (e.g., YCbCr to RGB), color correction, cropping or resampling, or any other processing to prepare the decoded picture data 31 for display by, for example, the display device 34.

[0108] The display device 34 of the destination device 14 is configured to receive the post-processed picture data 33 and, for example, display the picture to a user or viewer. The display device 34 may be or include any type of display that presents the reconstructed picture, such as an integrated or external display or monitor. The display may be or include, for example, a liquid crystal display (LCD), an organic light-emitting diode (OLED) display, a plasma display, a projector, a micro-LED display, a liquid crystal on silicon (LCoS), a digital light processor (DLP), or any other type of display.

[0109] Figure 1A shows the source device 12 and the destination device 14 as separate devices, but the device embodiments may also include the functions of both or both, the source device 12 or its corresponding function and the destination device 14 or its corresponding function. In such embodiments, the source device 12 or its corresponding function and the destination device 14 or its corresponding function may be implemented using the same hardware and / or software, or by separate hardware and / or software, or any combination thereof.

[0110] As will be apparent to those skilled in the art based on the description, the presence and (exact) division of different units or functions within the source device 12 and / or destination device 14 as shown in Figure 1A may vary depending on the actual device and application.

[0111] The encoder 20 (e.g., video encoder 20) or the decoder 30 (e.g., video decoder 30), or both the encoder 20 and the decoder 30, may be implemented via processing circuits, such as one or more microprocessors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), discrete logic, hardware, dedicated video coding, or any combination thereof, as shown in Figure 1B. The encoder 20 may be implemented via processing circuits 46 to embody various modules, as described with respect to the encoder 20 in Figure 2 and / or any other encoder system or subsystem described herein. The decoder 30 may be implemented via processing circuits 46 to embody various modules, as described with respect to the decoder 30 in Figure 3 and / or any other decoder system or subsystem described herein. The processing circuits may be configured to perform various operations, as described below. As shown in Figure 5, if the technology is partially implemented in software, the device may store instructions for the software in a suitable non-temporary computer-readable storage medium, and may execute the instructions in hardware using one or more processors to perform the technology of this disclosure. Either the video encoder 20 or the video decoder 30 may be integrated as part of a combined encoder / decoder (CODEC) within a single device, for example, as shown in Figure 1B.

[0112] The source device 12 and destination device 14 may include any of a broad range of devices, including handheld or fixed devices of any kind, such as notebook or laptop computers, mobile phones, smartphones, tablets or tablet computers, cameras, desktop computers, set-top boxes, televisions, display devices, digital media players, video game consoles, video streaming devices (such as content service servers or content distribution servers), broadcast receiver devices, broadcast transmitter devices, etc., and may or may not use any kind of operating system. In some cases, the source device 12 and destination device 14 may be equipped for wireless communication. Therefore, the source device 12 and destination device 14 may also be wireless communication devices.

[0113] In some cases, the video coding system 10 shown in Figure 1A is merely an example, and the technology of the present invention may be applied to video coding configurations (e.g., video coding or video decoding) that do not necessarily involve any data communication between the coding device and the decoding device. In other examples, the data may be retrieved from local memory, streamed over a network, etc. The video coding device may code the data and store it in memory, and / or the video decoding device may retrieve the data from memory and decode it. In some examples, coding and decoding are performed by devices that do not communicate with each other but simply code the data into memory and / or retrieve the data from memory and decode it.

[0114] For the sake of explanation, embodiments of the present invention are described herein by reference to, for example, reference software for High-Efficiency Video Coding (HEVC) or Versatile Video Coding (VVC), and next-generation video coding standards developed by the ITU-T Video Coding Experts Group (VCEG) and the Joint Collaboration Team on Video Coding (JCT-VC) of the ISO / IEC 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.

[0115] Encoder and encoding method Figure 2 shows a schematic block diagram of an exemplary video encoder 20 configured to realize the technology of the present invention. In the example of Figure 2, the video encoder 20 includes an input 201 (or input interface 201), a residual calculation unit 204, a transformation processing unit 206, a quantization unit 208, an inverse quantization unit 210, an inverse transformation 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 processing unit 254, and a partition unit 262. The inter-prediction unit 244 may include a motion estimation unit and a motion compensation unit (not shown). The video encoder 20 as shown in Figure 2 may also be called a hybrid video encoder or a video encoder with a hybrid video codec.

[0116] The residual calculation unit 204, the conversion processing unit 206, the quantization unit 208, and the mode selection unit 260 may also be referred to as forming the forward signal path of the encoder 20. On the other hand, the inverse quantization unit 210, the inverse conversion 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 also be referred to as forming the reverse signal path of the video encoder 20, where the reverse signal path corresponds to the signal path of the decoder (see decoder 30 in Figure 3). The inverse quantization unit 210, the inverse conversion 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 referred to as forming the “built-in decoder” of the video encoder 20.

[0117] Picture and picture partition (picture and block) The encoder 20 may be configured, for example, to receive a picture 17 (or picture data 17) via input 201, for example, a picture of a sequence of pictures that form a video or video sequence. The received picture or picture data may also be a preprocessing picture 19 (preprocessing picture data 19). For brevity, the following description will refer to picture 17. Picture 17 may also be called the current picture or the picture to be coded (in particular, in video coding, to distinguish the current picture from other pictures, for example, pictures encoded and / or decoded before the same video sequence, i.e., the video sequence that also contains the current picture).

[0118] A (digital) picture is, or can be thought of as, a two-dimensional array or matrix of samples having intensity values. A sample in the array may also be called a pixel (short for picture element) or pel. 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, typically three color components are used; that is, a picture may or may contain three sample arrays. In the RGB format or color space, a picture contains corresponding red, green, and blue sample arrays. However, in video coding, each pixel is typically represented by a luminance and chrominance format or color space, e.g., YCbCr, which includes a luminance component represented by Y (sometimes L is used instead) and two chrominance components represented by Cb and Cr. The luminance (or abbreviated as luma) component Y represents brightness or gray level intensity (e.g., in a grayscale picture). On the other hand, the two chrominance (or chroma for short) components Cb and Cr represent chromaticity or color information components. Therefore, 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 to or from YCbCr format, and vice versa; the process is also known as color conversion or transformation. If the picture is monochrome, the picture may include only a luminance sample array. Therefore, a picture may be, for example, a luminance sample array in a monochrome format, or two corresponding arrays of luminance samples and chroma samples in 4:2:0, 4:2:2, and 4:4:4 color formats.

[0119] Embodiments of the video encoder 20 may include a picture partition unit (not shown in Figure 2) configured to partition a picture 17 into a plurality of (typically non-overlapping) picture blocks 203. These blocks may also be called root blocks, macro blocks (H.264 / AVC), coding tree blocks (CTB), or coding tree units (CTU) (H.265 / HEVC and VVC). The picture partition unit may be configured to use the same block size for all pictures in the video sequence and for the corresponding grid that defines the block size, or to change the block size between pictures or subsets or groups of pictures and partition each picture into the corresponding block.

[0120] In a further embodiment, the video encoder may be configured to directly receive blocks 203 of picture 17, for example, one, some, or all of the blocks that make up picture 17. Picture block 203 may also be called the picture block now or the picture block to be coded.

[0121] Similar to picture 17, picture block 203 is also a two-dimensional array or matrix of samples having intensity values ​​(sample values), or can be conceived as such, but with fewer dimensions than picture 17. In other words, block 203 may contain, for example, one sample array (e.g., a luma array in the case of monochrome picture 17, or a luma or chroma array in the case of a color picture) or three sample arrays (e.g., a luma and two chroma arrays in the case of color picture 17), or any other number and / or type of arrays 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, the block may be, for example, an M×N (M columns × N rows) array of samples, or an M×N array of conversion coefficients.

[0122] An embodiment of the video encoder 20 shown in Figure 2 may be configured to encode the picture 17 block by block, for example, encoding and prediction may be performed for each block 203.

[0123] An embodiment of the video encoder 20, as shown in Figure 2, may be further configured to partition and / or encode a picture by using slices (also called video slices), the picture may be partitioned into one or more slices (typically non-overlapping) or encoded using such slices, each slice may contain one or more blocks (e.g., CTUs).

[0124] Embodiments of the video encoder 20, as shown in Figure 2, may be further configured to partition and / or encode a picture by using tile groups (also called video tile groups) and / or tiles (also called video tiles), wherein the picture may be partitioned into or encoded using one or more (typically non-overlapping) tile groups, each tile group may include, for example, one or more blocks (e.g., CTUs) or one or more tiles, each tile may be, for example, rectangular in shape and may include one or more blocks (e.g., CTUs), for example, complete or partial blocks.

[0125] Residual calculation The residual calculation unit 204 may be configured to calculate the residual block 205 (also called residual 205) by, for example, subtracting the sample value of the prediction block 265 from the sample value of the picture block 203 for each sample (for each pixel) to obtain the residual block 205 in the sample domain, based on the picture block 203 and the prediction block 265 (further details regarding the prediction block 265 are provided below).

[0126] conversion The transformation processing unit 206 may be configured to obtain transformation coefficients 207 in the transformation domain by applying a transformation, such as a discrete cosine transform (DCT) or discrete sine transform (DST), to the sample values ​​of the residual block 205. The transformation coefficients 207 are also called transformation residual coefficients and may represent the residual block 205 in the transformation domain.

[0127] The conversion processing unit 206 may be configured to apply an integer approximation of DCT / DST, such as the conversion specified for H.265 / HEVC. Compared to the orthogonal DCT conversion, such an integer approximation is typically scaled by a specific factor. Further scaling factors are applied as part of the conversion process to maintain the norm of the residual blocks processed by the forward and inverse conversions. The scaling factors are typically selected based on specific constraints, such as the scaling factor being a power of 2 for the shift operation, the bit depth of the conversion coefficients, and the trade-off between precision and implementation cost. A specific scaling factor may be specified, for example, for the inverse conversion by the inverse conversion processing unit 212 (and, for example, the corresponding inverse conversion by the inverse conversion processing unit 312 in the video decoder 30), and a corresponding scaling factor may be specified accordingly, for example, for the forward conversion by the conversion processing unit 206 in the encoder 20.

[0128] Embodiments of the video encoder 20 (each a conversion processing unit 206) may be configured to output conversion parameters, for example, the type of conversion or multiple conversions, which are encoded or compressed, for example, directly or via the entropy coding unit 270, so that, for example, the video decoder 30 may receive and use the conversion parameters for decoding.

[0129] Quantization The quantization unit 208 may be configured to quantize the transformation coefficient 207 by, for example, applying scalar quantization or vector quantization to obtain the quantized coefficient 209. The quantized coefficient 209 may also be called the quantized transformation coefficient 209 or the quantized residual coefficient 209.

[0130] The quantization process may reduce the bit depth associated with some or all of the conversion coefficients 207. For example, n-bit conversion coefficients may be truncated to m-bit conversion coefficients during quantization, where n is greater than m. The degree of quantization may be changed by adjusting the quantization parameter (QP). For example, in scalar quantization, different scaling may be applied to achieve finer or coarser quantization. Smaller quantization step sizes correspond to finer quantization, while larger quantization step sizes correspond to coarser quantization. Applicable quantization steps may be indicated by the quantization parameter (QP). The quantization parameter may be, for example, an index to a given set of applicable quantization step sizes. For example, a small quantization parameter may correspond to finer quantization (smaller quantization step size), a large quantization parameter may correspond to coarser quantization (larger quantization step size), and vice versa. Quantization may involve division by the quantization step size, and the corresponding and / or inverse dequantization by the inverse quantization unit 210 may involve multiplication by the quantization step size. Some standards, e.g., embodiments by HEVC, may be configured to use quantization parameters to determine the quantization step size. Generally, the quantization step size may be calculated based on the quantization parameters using a fixed-point approximation of the equations involving division. Further scaling factors for quantization and dequantization may be introduced to restore the norm of the residual block, which may be modified due to the scaling used in the fixed-point approximation of the equations for the quantization step size and quantization parameters. In one exemplary implementation, the scaling of the inverse transform and dequantization may be combined. Alternatively, a customized quantization table may be used and signaled, for example, from encoder to decoder in a bitstream. Quantization is an irreversible operation, and losses increase with increasing quantization step size.

[0131] Embodiments of the video encoder 20 (each a quantization unit 208) may be configured to output a quantization parameter (QP) which is encoded, for example, directly or via an entropy coding unit 270, so that, for example, the video decoder 30 may receive and apply the quantization parameter for decoding.

[0132] inverse quantization The inverse quantization unit 210 is configured to obtain the de-quantized coefficients 211 by applying the inverse of the quantization scheme applied by the quantization unit 208 to the quantized coefficients, for example, by applying the inverse of the quantization scheme applied by the quantization unit 208, based on or using the same quantization step size as the quantization unit 208. The de-quantized coefficients 211 are also called de-quantized residual coefficients 211 and may correspond to the transformation coefficients 207, although they are typically not identical to the transformation coefficients due to quantization losses.

[0133] Inverse Transform The inverse transformation processing unit 212 is configured to obtain a reconstructed residual block 213 (or the corresponding antiquantized coefficient 213) in the sample domain by applying the inverse transformation of the transformation applied by the transformation processing unit 206, for example, the inverse discrete cosine transform (DCT) or the inverse discrete sine transform (DST), or other inverse transformations. The reconstructed residual block 213 may also be called the transformation block 213.

[0134] Reconstruction The reconstruction unit 214 (e.g., an adder or totaler 214) is configured to obtain the reconstructed block 215 in the sample domain by adding the transformed 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 prediction block 265 sample by sample.

[0135] filtering The loop filter unit 220 (or simply "loop filter" 220) is configured to filter the reconstructed block 215 to obtain a filtered block 221, or more generally, to filter the reconstructed sample to obtain a filtered sample. The loop filter unit is configured, for example, to smooth pixel transitions or to 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, such as a bilateral filter, an adaptive loop filter (ALF), a sharpening, smoothing filter, or a co-filter, or any combination thereof. Although the loop filter unit 220 is shown as an in-loop filter in Figure 2, in other configurations, the loop filter unit 220 may be implemented as a post-loop filter. The filtered block 221 may also be called a filtered reconstructed block 221.

[0136] Embodiments of the video encoder 20 (each a loop filter unit 220) may be configured to output loop filter parameters (such as sample-adaptive offset information) that are encoded, for example, directly or via an entropy coding unit 270, so that, for example, the decoder 30 may receive and apply the same loop filter parameters or the respective loop filters for decoding.

[0137] Decode picture buffer The decoded picture buffer (DPB) 230 may be a memory that stores a reference picture or generally reference picture data for encoding video data by the video encoder 20. The DPB 230 may be formed from any of various 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 be further configured to store the same current picture or a different picture, for example, other previously filtered blocks of a previously reconstructed picture, for example, a previously reconstructed and filtered block 221, for example, for interpretation, it may provide a fully reconstructed, i.e., decoded picture (and corresponding reference blocks and samples) and / or a partially reconstructed current picture (and corresponding reference blocks and samples). The decoded picture buffer (DPB) 230 may also be configured to store one or more unfiltered reconstructed blocks 215, or generally, for example, if the reconstructed blocks 215 are not filtered by the loop filter unit 220, unfiltered reconstructed samples, or other further processed versions of any of the reconstructed blocks or samples.

[0138] Mode selection (partition and prediction) The mode selection unit 260 includes a partition unit 262, an inter-prediction unit 244, and an intra-prediction unit 254, and is configured to receive or acquire 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 from the same (current) picture and / or one or more previously decoded pictures, e.g., from the decoded picture buffer 230 or other buffers (e.g., line buffers not shown). The reconstructed picture data is used as reference picture data for predictions, e.g., inter-prediction or intra-prediction, to acquire prediction blocks 265 or predictors 265.

[0139] The mode selection unit 260 may be configured to determine or select a partition (including no partition) for the current block prediction mode and a prediction mode (e.g., intra or inter-prediction mode), and to generate a corresponding prediction block 265 to be used for calculating the residual block 205 and for reconstructing the reconstructed block 215.

[0140] Embodiments of the mode selection unit 260 may be configured to select partition and prediction modes (for example, from those supported or available by the mode selection unit 260) that provide the best fit, or in other words, minimum residual (minimum residual meaning better compression for transmission or storage) or minimum signaling overhead (minimum signaling overhead meaning better compression for transmission or storage), or that consider or balance both. The mode selection unit 260 may be configured to determine the partition and prediction modes based on rate distortion optimization (RDO), i.e., to select a prediction mode that provides the minimum rate distortion. In this context, terms such as “best,” “minimum,” and “optimal” do not necessarily refer to an overall “best,” “minimum,” and “optimal,” but may refer to termination or selection criteria such as a value above or below a threshold, or the satisfaction of other constraints that result in a potentially “suboptimal selection” but reduce complexity and processing time.

[0141] In other words, the partition unit 262 may be configured to partition block 203 into smaller block partitions or subblocks (which also form blocks) by repeatedly using, for example, quad-tree partitioning (QT), binary partitioning (BT), or triple-tree partitioning (TT), or any combination thereof, and to perform predictions for each of the block partitions or subblocks, for example, mode selection includes selecting the tree structure of the partitioned block 203, and prediction modes are applied to each of the block partitions or subblocks.

[0142] The following describes in more detail the partitioning (by the partition unit 260, for example) and prediction (by the inter-prediction unit 244 and intra-prediction unit 254) processes performed by the exemplary video encoder 20.

[0143] partition The partition unit 262 may now partition (or divide) block 203 into smaller partitions, for example, smaller blocks of a square or rectangular size. These smaller blocks (also called subblocks) may be further partitioned into even smaller partitions. This is also called a tree partition or hierarchical tree partition. For example, the root block at root tree level 0 (hierarchical level 0, depth 0) may be recursively partitioned into, for example, two or more blocks at the next lower tree level, for example, a node at tree level 1 (hierarchical level 1, depth 1), and these blocks may be further partitioned into, for example, two or more blocks at the next lower tree level, for example, tree level 2 (hierarchical level 2, depth 2), until the partitioning ends, for example, because a termination criterion is met, for example, because the maximum tree depth or minimum block size has been reached. Blocks that are not further partitioned are also called leaf blocks or leaf nodes of the tree. A tree that uses partitions into two partitions is called a binary tree (BT), a tree that uses partitions into three partitions is called a ternary tree (TT), and a tree that uses partitions into four partitions is called a quad tree (QT).

[0144] As described above, the term “block” as used herein may refer to a part of a picture, particularly a square or rectangular portion. For example, with reference to 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 to a corresponding block, such as a coding tree block (CTB), a coding block (CB), a transform block (TB), or a prediction block (PB).

[0145] For example, a coding tree unit (CTU) may be or include a CTB of a luma sample, two corresponding CTBs of a chroma sample of a picture having three sample sequences, or a CTB of a sample of a picture coded using a syntax structure used to code a monochrome picture or three separate color planes and samples. Correspondingly, a coding tree block (CTB) may be an N×N block of samples for some value N, such that the division of components into a CTB is a partition. A coding unit (CU) may be or include a coding block of a luma sample, two corresponding coding blocks of a chroma sample of a picture having three sample sequences, or a coding block of a sample of a picture coded using a syntax structure used to code a monochrome picture or three separate color planes and samples. Correspondingly, a coding block (CB) may be an M×N block of samples for some values ​​M and N, such that the division of a CTB into a coding block is a partition.

[0146] For example, in an embodiment using HEVC, a coding tree unit (CTU) may be partitioned into CUs by using a quadtree structure, which is represented as a coding tree. The decision of whether to code a picture region using interpicture (time) prediction or intrapicture (spatial) prediction is made at the CU level. Each CU can be further partitioned into one, two, or four PUs, according to the PU partitioning type. Within a single PU, the same prediction process is applied, and relevant information is sent to the decoder for each PU. After obtaining residual blocks by applying the prediction process based on the PU partitioning type, the CU can be partitioned into transform units (TUs) according to other quadtree structures similar to the coding tree for the CU.

[0147] For example, in an embodiment of the latest video coding standard currently under development called Versatile Video Coding (VVC), combined quad-tree and binary tree (QTBT) partitions are used, for example, to partition coding blocks. In the QTBT block structure, CUs can be either square or rectangular in shape. For example, a coding tree unit (CTU) is first partitioned by a quad-tree structure. The quad-tree leaf nodes are further partitioned by a binary or ternary (or triple) tree structure. The partitioned leaf nodes are called coding units (CUs), and their segmentation is used for prediction and transformation processing without 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 triple-tree partitioning, may be used with the QTBT block structure.

[0148] In one example, the mode selection unit 260 of the video encoder 20 may be configured to perform any combination of the partitioning techniques described herein.

[0149] As described above, the video encoder 20 is configured to determine or select the best or most optimal prediction mode from a set of prediction modes (for example, a predetermined set). The set of prediction modes may include, for example, an intra-prediction mode and / or an inter-prediction mode.

[0150] Intra Prediction The set of intra-prediction modes may include 35 different intra-prediction modes, such as DC (or mean) mode and non-directional modes like planar mode, or directional modes like those defined for HEVC, or it may include 67 different intra-prediction modes, such as DC (or mean) mode and non-directional modes like planar mode, or directional modes like those defined for VVC.

[0151] The intra-prediction unit 254 is configured to use reconfigured samples of adjacent blocks of the same current picture to generate an intra-prediction block 265 according to a certain intra-prediction mode from a set of intra-prediction modes.

[0152] The intra-prediction unit 254 (or generally the mode selection unit 260) is further configured to output intra-prediction parameters (or generally information indicating the selected intra-prediction mode for a block) to the entropy coding unit 270 in the form of syntax elements 226 for inclusion in the coded picture data 21, so that, for example, the video decoder 30 may receive and use the prediction parameters for decoding.

[0153] Interpretation The set of interpretation modes (or possible ones) depends on the available reference picture (i.e., a previous, at least partially decoded picture stored in DBP230) and other interpretation parameters, such as whether the entire reference picture is used to search for the best-fitting reference block, or only a portion of the reference picture, such as the search window area around the current block's region, and / or whether pixel interpolation, such as half / semi-per and / or quarter-per interpolation, is applied.

[0154] In addition to the prediction modes described above, skip mode and / or direct mode may also be applied.

[0155] The interpretation unit 244 may include a motion estimation (ME) unit and a motion compensation (MC) unit (neither of which are shown in Figure 2). The motion estimation unit may be configured to receive or acquire, for motion estimation, a picture block 203 (the current block 203 of the current picture 17) and a decoded picture 231, or at least one or more previously reconstructed blocks, for example, one or more other / different previously reconstructed blocks of a decoded picture 231. For example, a video sequence may include a current picture and a previous decoded picture 231, or in other words, the current picture and the previous decoded picture 231 may be part of or form part of a sequence of pictures that make up the video sequence.

[0156] The encoder 20 may be configured, for example, to select a reference block from multiple reference blocks of the same or different pictures of multiple other pictures, and to provide the motion estimation unit with an offset (spatial offset) between the reference picture (or reference picture index) and / or the position (x,y coordinates) of the reference block and the position of the current block as an interpretation parameter. This offset is also called a motion vector (MV).

[0157] The motion compensation unit is configured to acquire, for example, interprediction parameters, and perform interprediction based on or using the interprediction parameters to acquire interprediction block 265. Motion compensation performed by the motion compensation unit may include fetching or generating prediction blocks based on the motion / block vector determined by motion estimation, and possibly performing interpolation to sub-pixel precision. Interpolation filtering may generate further pixel samples from known pixel samples, thus potentially increasing the number of candidate prediction blocks that can be used to code picture blocks. Now, upon receiving the motion vector of a picture block, the motion compensation unit may find the prediction block pointed to by the motion vector in one of the reference picture lists.

[0158] The motion compensation unit may also generate syntax elements associated with blocks and video slices for use by the video decoder 30 when decoding picture blocks of video slices. In addition to or as an alternative to slices and their respective syntax elements, tile groups and / or tiles and their respective syntax elements may be generated or used.

[0159] Entropy coding The entropy coding unit 270 is configured to obtain encoded picture data 21 that can be output via output 272 in the form of an encoded bitstream 21, for example, by applying or bypassing (uncompressing) an entropy coding algorithm or scheme (e.g., variable length coding (VLC) scheme, context adaptive VLC (CAVLC) scheme, arithmetic coding scheme, binarization, context adaptive binary arithmetic coding (CABAC) scheme, syntax-based context-adaptive binary arithmetic coding (SBAC) scheme, probability interval partitioning entropy (PIPE) coding scheme, or other entropy coding methods or techniques) to the quantized coefficients 209, inter-prediction parameters, intra-prediction parameters, loop filter parameters and / or other syntax elements, for example, an encoded picture data 21 that can be output via output 272 in the form of an encoded bitstream 21, so that, for example, a video decoder 30 may receive and use the parameters for decoding. The encoded bitstream 21 may be transmitted to the video decoder 39, or it may be stored in memory for later transmission or retrieval by the video decoder 30.

[0160] Other structural variations of the video encoder 20 can be used to encode video streams. For example, a non-conversion-based encoder 20 can directly quantize the residual signal for a given block or frame without a conversion processing unit 206. In other implementations, the encoder 20 may have a quantization unit 208 and an inverse quantization unit 210 coupled into a single unit.

[0161] Decoder and decoding method Figure 3 shows an example of a video decoder 30 configured to realize the technology of the present invention. The video decoder 30 is configured to receive encoded picture data 21 (e.g., encoded bitstream 21) encoded by, for example, the encoder 20, in order to obtain a decoded picture 331. The encoded picture data or bitstream includes information for decoding the encoded picture data, for example, data representing picture blocks and associated syntax elements of an encoded video slice (and / or tile group or tile).

[0162] In the example in Figure 3, the decoder 30 includes an entropy decoding unit 304, an inverse quantization unit 310, an inverse transformation processing unit 312, a reconstruction unit 314 (e.g., a totalizer 314), a loop filter 320, a decoded picture buffer (DBP) 330, a mode application unit 360, an inter-prediction unit 344, and an intra-prediction unit 354. The inter-prediction unit 344 may be or may include a motion compensation unit. In some examples, the video decoder 30 may perform a decoding path that is generally the reverse of the encoding path described for the video encoder 100 from Figure 2.

[0163] As described with respect to encoder 20, the inverse quantization unit 210, inverse processing unit 212, reconstruction unit 214, loop filter 220, decoded picture buffer (DPB) 230, inter-prediction unit 344, and intra-prediction unit 354 may also be called the “internal decoder” of video encoder 20. Thus, the inverse quantization unit 310 may be functionally identical to the inverse quantization unit 110, the inverse processing unit 312 may be functionally identical to the inverse processing unit 212, the reconstruction unit 314 may be functionally identical to the reconstruction unit 214, the loop filter 320 may be functionally identical to the loop filter 220, and the decoded picture buffer 330 may be functionally identical to the decoded picture buffer 230. Therefore, the descriptions provided for each unit and function of video encoder 20 apply correspondingly to each unit and function of video decoder 30.

[0164] Entropy decoding The entropy decoding unit 304 is configured to parse the bitstream 21 (or generally the encoded picture data 21) and, for example, perform entropy decoding on the encoded picture data 21 to obtain, for example, quantized coefficients 309 and / or decoded coding parameters (not shown in Figure 3), such as inter-prediction parameters (e.g., reference picture index and motion vector), intra-prediction parameters (e.g., intra-prediction mode or index), transformation 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 an encoding scheme such as those described with respect to 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 application 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 video block level. In addition to or as an alternative to slices and their respective syntax elements, tile groups and / or tiles and their respective syntax elements may be received and / or used.

[0165] inverse quantization The inverse quantization unit 310 may be configured to receive quantization parameters (QP, quantization parameter) (or information generally related to inverse quantization) and quantized coefficients from encoded picture data 21 (for example, by parsing and / or decoding by an entropy decoding unit 304), and to apply inverse quantization to the decoded quantized coefficients 309 based on the quantization parameters to obtain de-quantized coefficients 311, which may also be called transformed coefficients 311. The inverse quantization process may include using quantization parameters determined by the video encoder 20 for each video block in a video slice (or tile or tile group) to determine the degree of quantization and the degree of inverse quantization to be applied.

[0166] Inverse Transform The inverse transform processing unit 312 may be configured to receive the dequantized coefficients 311, also called the transform coefficients 311, and to apply a transform to the dequantized coefficients 311 in order to obtain the reconstructed residual block 213 in the sample domain. The reconstructed residual block 213 may also be called the transform block 313. The transform may be an inverse transform, such as an inverse DCT, inverse DST, inverse integer transform, or a conceptually similar inverse transform process. The inverse transform processing unit 312 may be further configured to receive transform parameters or corresponding information from the encoded picture data 21 (for example, by parsing and / or decoding by the entropy decoding unit 304) to determine the transform to be applied to the dequantized coefficients 311.

[0167] Reconstruction The reconstruction unit 314 (for example, an adder or totalizer 314) may be configured to obtain the reconstructed block 315 in the sample domain by adding the reconstructed residual block 313 to the prediction block 365, for example by adding the sample value of the reconstructed residual block 313 to the sample value of the prediction block 365.

[0168] filtering The loop filter unit 320 (either within or after the coding loop) is configured to filter the reconstructed block 315 to obtain the filtered block 321, for example, to smooth pixel transitions or to improve video quality. The 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, smoothing filter, or a co-filter, or any combination thereof. The loop filter unit 320 is shown in Figure 3 as an in-loop filter, but in other configurations, the loop filter unit 320 may be implemented as a post-loop filter.

[0169] Decode picture buffer The decoded video block 321 of the picture is then stored in the decoded picture buffer 330, which stores the decoded picture 331 as a reference picture for later motion compensation for other pictures and / or for output of their respective displays.

[0170] The decoder 30 is configured to output the decoded picture 311, for example, via output 312, for presentation or viewing by the user.

[0171] prediction The inter-prediction unit 344 may be identical to the inter-prediction unit 244 (in particular, the motion compensation unit), and the intra-prediction unit 354 may be functionally identical to the inter-prediction unit 254, and they perform partition or partition decisions and predictions based on the respective information received from the partition and / or prediction parameters or encoded picture data 21 (for example, by parsing and / or decoding by the entropy decoding unit 304). The mode application unit 360 may be configured to perform predictions (intra or inter-predictions) block by block based on the reconstructed picture, block or each (filtered or unfiltered) sample to obtain a predicted block 365.

[0172] When a video slice is coded as an intra-coded (I) slice, the intra-prediction unit 354 of the mode application unit 360 is configured to generate a prediction block 365 for the picture block of the current video slice based on the signaled intra-prediction mode and data from blocks decoded before the current picture. When a video picture is coded as an intercoded (i.e., B or P) slice, the inter-prediction unit 344 (e.g., motion compensation unit) of the mode application unit 360 is configured to generate a prediction block 365 for the video block of the current video slice based on motion vectors and other syntax elements received from the entropy decoding unit 304. In inter-prediction, the prediction block may be generated from one of the reference pictures in one of the reference picture lists. The video decoder 30 may configure the reference frame list, list 0 and list 1 using default configuration techniques based on the reference pictures stored in the DPB 330. The same or similar may apply to embodiments that use tile groups (e.g., video tile groups) and / or tiles (e.g., video tiles) in addition to or as an alternative to slices (e.g., video slices), for example, video may be coded using I, P, or B tile groups and / or tiles.

[0173] The mode-applying unit 360 is configured to determine prediction information for video blocks in the current video slice by parsing motion vectors or related information and other syntax elements, and uses the prediction information to generate prediction blocks for the current video block being decoded. For example, the mode-applying 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 in the video slice, the inter-prediction slice type (e.g., B-slice, P-slice, or GPB-slice), configuration information for one or more of the slice's reference picture lists, the motion vector for each inter-coded video block in the slice, the inter-prediction state for each inter-coded video block in the slice, and other information for decoding the video blocks in the current video slice. The same or similar may apply to, or thereafter, embodiments that use tile groups (e.g., video tile groups) and / or tiles (e.g., video tiles) in addition to or as an alternative to slices (e.g., video slices), for example, video may be coded using I, P, or B tile groups and / or tiles.

[0174] Embodiments of the video decoder 30, as shown in Figure 3, may be configured to partition and / or decode a picture using slices (also called video slices), the picture may be partitioned into one or more slices (typically non-overlapping) or decoded using such slices, each slice may contain one or more blocks (e.g., CTUs).

[0175] Embodiments of the video decoder 30, as shown in Figure 3, may be configured to partition and / or decode a picture using tile groups (also called video tile groups) and / or tiles (also called video tiles), wherein the picture may be partitioned into or decoded using one or more (typically non-overlapping) tile groups, each tile group may, for example, contain one or more blocks (e.g., CTUs) or one or more tiles, each tile may, for example, be rectangular in shape and contain one or more blocks (e.g., CTUs), for example, complete or partial blocks.

[0176] Other variations of the video decoder 30 can be used to decode encoded picture data 21. For example, the decoder 30 can generate an output video stream without a loop filter unit 320. For example, a non-transformation-based decoder 30 can directly dequantize the residual signal for a particular block or frame without an inverse transformation unit 312. In other implementations, the video decoder 30 may have an inverse quantization unit 310 and an inverse transformation unit 312 coupled into a single unit.

[0177] It should be understood that in encoder 20 and 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 clipping or shifting may be performed on the processing result of interpolation filtering, motion vector derivation, or loop filtering.

[0178] It should be noted that further operations may be applied to the currently derived motion vectors of a block (including, but not limited to, control point motion vectors in affine mode, subblock motion vectors in affine, planar, and ATMVP modes, time motion vectors, etc.). For example, the value of a motion vector is constrained to a predetermined range according to its representation bits. If the representation bits of a motion vector are bitDepth, the range is -2^(bitDepth-1) to 2^(bitDepth-1)-1, where "^" means exponentiation. For example, if bitDepth is set to equal 16, the range is -32768 to 32767, and if bitDepth is set to equal 18, the range is -131072 to 131071. For example, the value of a derived motion vector (e.g., the MV of four 4x4 subblocks in one 8x8 block) is constrained so that the maximum difference between the integer parts of the MVs of the four 4x4 subblocks is not greater than N pixels, such as not being greater than 1 pixel. Here, we provide two methods for constraining the motion vector according to bitDepth.

[0179] Method 1: Remove the overflow MSB (most significant bit) using flow calculation. 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) Here, mvx is the horizontal component of the motion vector of an image block or subblock, mvy is the vertical component of the motion vector of an image block or subblock, and ux and uy represent the intermediate values.

[0180] For example, when the value of mvx is -32769, after applying equations (1) and (2), the resulting value is 32767. In a computer system, decimal values are stored as two's complements. The two's complement of -32769 is 1,0111,1111,1111,1111 (17 bits), and in this case, the MSB is discarded, so 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)

[0181] As shown in equations (5) to (8), the operation may be applied between the sum of mvp and mvd.

[0182] Method 2: Remove the overflow 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) Here, vx is the horizontal component of the motion vector of an image block or sub-block, vy is the vertical component of the motion vector of an image block or sub-block, x, y, and z respectively correspond to the three input values of the MV clipping process, and the definition of the function Clip3 is as follows.

Number

[0183] Figure 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 embodiments of the disclosure described herein. In the embodiment, the video coding device 400 may be a decoder such as the video decoder 30 in Figure 1A or an encoder such as the video encoder 20 in Figure 1A.

[0184] The video coding device 400 includes an inlet 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 exit port 450 (or output port 450) for transmitting data, and memory 460 for storing data. The video coding device 400 may also include optical-to-electrical (OE) and electrical-to-optical (EO) components coupled to the inlet port 410, receiver unit 420, transmitter unit 440, and exit port 450 for the exit or input of optical or electrical signals.

[0185] The processor 430 is implemented by hardware and software. The processor 430 may be implemented as one or more CPU chips, cores (e.g., a multi-core processor), FPGAs, ASICs, and DSPs. The processor 430 communicates with the input port 410, the receiver unit 420, the transmitter unit 440, the output port 450, and the memory 460. The processor 430 includes a coding module 470. The coding module 470 implements the embodiments of the disclosure described above. For example, the coding module 470 implements, processes, prepares, or provides various coding operations. Thus, what is included in the coding module 470 provides a substantial improvement to the functionality of the video coding device 400, resulting in the conversion 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.

[0186] 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 such programs when they are selected for execution and for storing instructions and data read during program execution. 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).

[0187] Figure 5 is a simplified block diagram of a device 500 which may be used as one or both of the source device 12 and destination device 14 from Figure 1 according to an exemplary embodiment.

[0188] The processor 502 within the device 500 may be a central processing unit. Alternatively, the processor 502 may be any other type of device, or multiple devices, that currently exist or may be developed in the future, capable of manipulating or processing information. The implementation of the disclosure can be carried out with a single processor, e.g., processor 502, as shown in the figure, but advantages in speed and efficiency can be achieved by using more than one processor.

[0189] The memory 504 within the device 500 can be, in implementation, a read-only memory (ROM) device or a random access memory (RAM) device. Any other suitable type of storage device can be used as memory 504. Memory 504 may contain code and data 506 accessed by the processor 502 using the bus 512. Memory 504 may further contain an operating system 508 and an application program 510, the application program 510 including at least one program that enables the processor 502 to perform the method described herein. For example, the application program 510 may include applications 1 to N, further including a video coding application that performs the method described herein.

[0190] The device 500 may also include one or more output devices, such as a display 518. The display 518 may, in one example, be a touch-sensitive display that combines a display with a touch-sensitive element capable of sensing touch input. The display 518 can be coupled to the processor 502 via the bus 512.

[0191] Although shown here as a single bus, the bus 512 of device 500 can consist of multiple buses. Furthermore, the secondary storage 514 can be directly coupled to other components of device 500 or accessed via a network, and may include a single integrated unit such as a memory card or multiple units such as multiple memory cards. Thus, device 500 can be implemented in a wide range of configurations.

[0192] Parameter set The parameter sets are fundamentally similar and share the same basic design goals: bitrate efficiency, error recovery, and the provision of a system layer interface. HEVC (ITU-T H.265) has a hierarchy of parameter sets, including the Video Parameter Set (VPS), Sequence Parameter Set (SPS), and Picture Parameter Set (PPS), which are similar to their counterparts in AVC and VVC. Each slice references a single active PPS, SPS, and VPS to access the information used to decode the slice. The PPS contains information applicable to all slices within a picture; therefore, all slices within a picture must reference the same PPS. Slices in different pictures are permitted to reference the same PPS. Similarly, the SPS contains information applicable to all pictures within the same coded video sequence.

[0193] While PPS may differ for different pictures, it is common for many or all pictures in a coded video sequence to refer to the same PPS. Reusing parameter sets is bitrate-efficient because it avoids the need to send shared information multiple times. It is also loss-robust because it allows the contents of the parameter set to be carried over a more reliable external communication link to ensure they are not lost, or to be frequently repeated within the bitstream.

[0194] Sequence Parameter Set (SPS) SPS is applied to one or more layers of a coded video sequence and contains parameters that do not change for each picture within the coded video sequence. In particular, SPS includes signaling information for subpictures.

[0195] Some parts of the table below show snapshots of subpicture signaling in SPS in ITU JVET-Q2001-v11, and the download links are as follows. http: / / phenix.it-sudparis.eu / jvet / doc_end_user / documents / 17_Brussels / wg11 / JVET-Q2001-v11.zip For the remainder of this application, this document will be referred to as VVC Draft 8 for abbreviation. [Table 1] TIFF0007892931000003.tif115166

[0196] Several syntax elements within the SPS signal the location information and control flags for each subpicture. The location information for the i-th subpicture includes the following: - subpic_ctu_top_left_x[i], which indicates the horizontal component of the top-left coordinate of subpicture i within the picture, or - subpic_ctu_top_left_y[i] indicates the vertical component of the top-left coordinate of subpicture i within the picture, or • subpic_width_minus1[i] indicates the width of subpicture i within the picture, or • subpic_height_minus1[i] indicates the height of subpicture i within the picture.

[0197] Some syntax elements, such as sps_num_subpics_minus1, indicate the number of subpictures within a picture.

[0198] CTU, slice, tile, and picture partitioning to subpictures Partitioning pictures to the CTU A picture is divided into a series of coding tree units (CTUs). The term CTU is sometimes used interchangeably with CTB (coding tree block). In one example, the term CTU is the same as the definition of CTU in ITU-T H.265. For a picture with three sample arrays, a CTU contains an N×N block of chroma samples and two corresponding blocks of chroma samples. Figure 6 shows an example of a picture divided into CTUs. The size of the CTUs may be the same except for those located at the picture boundaries (where incomplete CTUs may exist).

[0199] Picture partitioning on tiles In some examples, when tiling is enabled, a picture is divided into groups of rectangular CTUs separated by vertical and / or horizontal boundaries. The vertical and horizontal tile boundaries traverse the picture from top to bottom and from the left picture boundary to the right picture boundary, respectively. Indicative information related to the positions of the horizontal and vertical tile boundaries is coded into the bitstream.

[0200] Figure 7 illustrates the partitioning of a picture into nine tiles. In this example, tile boundaries are indicated by bold dashed lines. CTU's tile-based raster scan order is performed using nine tiles of different sizes within the picture.

[0201] When there are more than one tile that vertically divides the picture, the scan order of the CTUs is changed relative to the raster scan order of the CTUs within the picture. The CTUs are scanned according to the following rules:

[0202] 1. Tiles are scanned from left to right and top to bottom in raster scan order, which is called tile scan order. This means that starting with the top-left tile, all tiles in the same tile row are scanned from left to right. Then, starting with the first tile in the second tile row (the row below), all tiles in the second tile row are scanned from left to right. This process is repeated until all tiles have been scanned.

[0203] 2. For each tile, the CTUs within that tile are scanned in raster scan order. For each row of CTUs, the CTUs are scanned from left to right, and the row of CTUs is scanned from top to bottom. Figure 7 illustrates the scan order of CTUs within a tile, where the numbers corresponding to the CTUs indicate the scan order.

[0204] The tiles provide a partition of a picture in such a way that each tile can be decoded independently of other tiles in the same picture, and the decoding exhibits entropy, residuals, and predictive decoding. Furthermore, the tiles make it possible to partition a picture into regions of similar size. Thus, it becomes possible to process the tiles of a picture in parallel, which is preferable for multi-core processing environments where each processing core is identical to the others.

[0205] The terms processing order and scan order are used in this application as follows:

[0206] The process indicates the encoding or decoding of CTUs within the encoder or decoder. The scan order relates to the indexing of a particular partition within a picture. CTUs are indexed in ascending order within a picture according to the specified scan order. The CTU scan order within a tile refers to how the CTUs within the tile are indexed, which may not be the same as the order in which they are processed (i.e., the processing order).

[0207] Partitioning a picture into a slice The concept of slicing provides a partition of a picture in such a way that each slice can be decoded independently of other slices of the same picture, and the decoding exhibits entropy, residuals, and predictive decoding. The difference from tiling is that slices can have any shape other than rectangles (making them more flexible in terms of partitioning possibilities), and the purpose of slice partitioning is not for parallel processing, but for packet size matching and error tolerance in a transmission environment.

[0208] A slice may contain a complete picture or a portion of a picture. According to ITU-T H.265, a slice contains a sequence of CTUs of pictures in processing order. A slice is identified according to its starting CTU address, which is signaled in the slice header, picture parameter set, or other unit. For example, when a slice needs to contain integer tiles, it may be identified according to its starting tile address.

[0209] In VVC Draft 8, a slice contains an integer tile, or a continuous row of integer CTUs within a picture tile. Therefore, a vertical slice boundary is also a vertical tile boundary. A slice's horizontal boundary may not be a tile boundary, and a horizontal CTU boundary may be contained within the tile. For example, when a tile is divided into multiple rectangular slices, each slice contains a complete, continuous row of integer CTUs within the tile.

[0210] In some examples, there are two slicing modes: raster scan slicing mode and rectangular slicing mode. In raster scan slicing mode, a slice contains a sequence of tiles in a tile raster scan of the picture. In rectangular slicing mode, a slice contains multiple tiles that together form a rectangular area of ​​the picture, or a slice contains multiple consecutive CTU rows of a single tile that together form a rectangular area of ​​the picture. Tiles within a rectangular slice are scanned in tile raster scan order within the rectangular area corresponding to that slice.

[0211] All slices of a picture together form the entire picture, and all CTUs of a picture are contained within one of its slices. The same rules apply to tiles and subpictures.

[0212] Partitioning a picture into a sub-picture A subpicture may be a rectangular partition of a picture. A subpicture may be the whole picture or a part of a picture. A subpicture is a partition of a picture in such a way that each subpicture can be decoded independently of other subpictures in the whole video sequence. In VVC Draft 8, a subpicture i can be decoded independently of other subpictures in the whole video sequence if the subpic_treated_as_pic_flag[i] directive is true for that subpicture i (for example, the value of subpic_treated_as_pic_flag[i] is 1).

[0213] The difference between a subpicture and a tile or slice is that a subpicture represents a video sequence that can be decoded independently. For tiles and slices, independent decoding is performed within a single picture of the video sequence.

[0214] In VVC Draft 8, a subpicture contains one or more slices that collectively cover the rectangular area of ​​the picture. Therefore, each subpicture boundary is always a slice boundary, and each vertical subpicture boundary is always a vertical tile boundary.

[0215] Figure 8 shows examples of tiles, slices, and subpictures. Figure 8 shows an example of a picture containing four tiles (two tile columns and two tile rows), four rectangular slices, and three subpictures. Subpicture 2 contains two slices, and subpictures 1 and 3 each contain one slice. Subpicture 1 contains two tiles, and subpictures 2 and 3 each contain one tile. The boundaries of the subpictures, slices, and tiles all coincide with the boundaries of the CTU. To distinguish them within the boundaries, they are shown with small offsets from each other.

[0216] In the example shown in Figure 8, the picture is partitioned into 216 CTUs, 4 tiles, 4 slices, and 3 subpictures. The value of sps_num_subpics_minus1 is 2, and the syntax element related to the position has the following value: About sub-picture 1 • subpic_ctu_top_left_x[0] is not signaled and is estimated as 0. • subpic_ctu_top_left_y[0] is not signaled and is estimated as 0. The value of subpic_width_minus1[0] is 8. The value of subpic_height_minus1[0] is 11. About sub-picture 2 The value of subpic_ctu_top_left_x[1] is 9. The value of subpic_ctu_top_left_y[1] is 0. The value of subpic_width_minus1[1] is 8. The value of subpic_height_minus1[1] is 5. About sub-picture 3 The value of subpic_ctu_top_left_x[2] is 9. The value of subpic_ctu_top_left_y[2] is 6. • subpic_width_minus1[2] is not signaled and is estimated to be 8. • subpic_height_minus1[2] is not signaled and is estimated to be 5.

[0217] Tile signaling The following table illustrates the signaling of tile size and coordinates for tiles within a picture, as disclosed in the RBSP syntax table of the VVC Draft 8 picture parameter set. [Table 2]

[0218] Tile partition information (e.g., tile address and tile dimensions) is typically coded into a parameter set. In the example above, the value of the instruction no_pic_partition_flag is coded into the bitstream, and the value of no_pic_partition_flag is used to indicate whether the picture is partitioned into slices and tiles. If no_pic_partition_flag is true (meaning the picture is not partitioned into slices or tiles), it is assumed that the picture is partitioned into only one slice and only one tile, and these boundaries are aligned with the picture boundaries. Otherwise (no_pic_partition_flag is false), the tile partition information is coded into the bitstream.

[0219] The value of the syntax element tile_column_width_minus1[i] indicates the width of the i-th tile column. The value of the syntax element tile_row_height_minus1[i] indicates the height of the i-th tile row.

[0220] The height of tile rows and the width of tile columns can be explicitly signaled in the bitstream or estimated according to the bitstream. The syntax elements num_exp_tile_columns_minus1 and num_exp_tile_rows_minus1 indicate the number of tile columns and tile rows, respectively, and the width and height of these tiles are explicitly signaled in the bitstream. The width and height of other tile columns and rows are estimated according to a function.

[0221] Tile indexing represents the "tile scan order within the picture." Tiles within a picture are ordered (scanned) according to the raster scan order, with the first tile in the top-left corner of the picture being tile number 0. The index increases from left to right within each tile row, and after the last tile in a tile row is scanned, it continues to the leftmost tile of the next tile row (one row below the current tile row).

[0222] The CTU (CTU scan order within a tile) is scanned in the raster scan order.

[0223] The tile-based scan order of CTUs within a picture indicates that the tile scan order within the picture and the CTU scan order within each tile follow each other simultaneously. In other words, • Picture tiles are scanned according to the tile scanning order within the picture. • One tile's CTU is fully scanned before any of the CTUs in different tiles. • For each tile, the CTUs are scanned in raster scan order (the CTU scan order within the tile).

[0224] Slice signaling The following table illustrates the signaling of the size and coordinates of rectangular slices within a picture, as disclosed in the RBSP syntax table of the VVC Draft 8 picture parameter set. [Table 3]

[0225] In VVC Draft 8, a slice contains one or more complete tiles, or a tile contains one or more complete slices. Therefore, the coordinates and size of a slice are given in relation to the tile partition. In VVC Draft 8, tile partitions are signaled by the picture parameter set. Slice partition information is signaled using tile mapping information.

[0226] In the table above, the value of the syntax element num_slices_in_pic_minus1 indicates the number of slices in the picture. The value of the syntax element Tile_idx_delta[i] indicates the difference between the tile index of the (i+1)th slice and the tile of the first tile of the i-th slice. For example, the tile index of the first tile of the first slice in the picture is 0. If the tile index of the first tile of the second slice is 5, then the value of Tile_idx_delta[0] is equal to 5. In this context, the tile index may also be used as the address of a slice; for example, the index of the first tile of a slice is the starting address of the slice.

[0227] The value of the syntax element slice_width_in_tiles_minus1[i] indicates the width of the i-th slice in the picture, in terms of tile count, and the value of the syntax element slice_height_in_tiles_minus1[i] indicates the height of the i-th slice in the picture, in terms of tile count (for example, as disclosed in VVC Draft 8, adding 1 to slice_width_in_tiles_minus1[i] specifies the width of the i-th rectangular slice in terms of tile columns, and adding 1 to slice_height_in_tiles_minus1[i] specifies the height of the i-th rectangular slice in terms of tile rows).

[0228] In the table above, if both the value of slice_width_in_tiles_minus1[i] and the value of slice_height_in_tiles_minus1[i] are equal to 0 (indicating that the i-th slice has dimensions of at most one tile in height and one tile in width), the value of the syntax element num_exp_slices_in_tile[i] is coded into the bitstream. The value of the syntax element num_exp_slices_in_tile[i] indicates the number of slices in the tile.

[0229] According to VVC Draft 8, a slice may contain multiple complete tiles, or a tile may contain multiple complete slices. As shown in the syntax table above, the number of tiles in a slice is indicated by slice_width_in_tiles_minus1[i] and slice_height_in_tiles_minus1[i]. Also, if the number of tiles in a slice is equal to 1, the number of slices in a tile is indicated by num_exp_slices_in_tile[i]. Therefore, if both the value of slice_width_in_tiles_minus1[i] and the value of slice_height_in_tiles_minus1[i] are equal to 1, the size of the slice may be less than or equal to the size of the tile.

[0230] The syntax element single_slice_per_subpic_flag being true (for example, the value of single_slice_per_subpic_flag being equal to 1) indicates that for all subpictures of a picture, there is only one slice for each subpicture (in this case, a subpicture cannot be divided into more than one slice).

[0231] According to one alternative signaling method, the slice start address and slice size are indicated in VVC Draft 8 according to the following steps:

[0232] 1. First, tile partition information is shown as a bitstream, and the index (tileIdx) is used to index the tiles in the picture (following the tile scan order in the picture). After this step, the index, coordinates, and size values ​​for each tile are obtained.

[0233] 2. The number of slices in the picture is signaled. For example, the number of slices can be indicated by the value of the syntax element num_slices_in_pic_minus1.

[0234] 3. For the first slice in the picture, the width and height of the slice are shown by the number of tiles. The starting address of the first slice is not explicitly signaled and is presumed to be tileIdx0, and the first tile in the picture is the first tile in the first slice of the picture.

[0235] 4. If the size of the first slice is equal to one tile in width and one tile in height, and the tile contains more than one CTU row, the value of the syntax element num_exp_slices_in_tile[0] is signaled, and the value of the syntax element num_exp_slices_in_tile[0] indicates the number of slices contained in that tile. The value of num_exp_slices_in_tile[0] may indicate the number of slices in the tile whose size is explicitly indicated in the bitstream, but there may be slices in the tile whose number and size are estimated based on the tile size, and slices whose size is explicitly signaled. Thus, the total number of slices in a tile may be determined according to num_exp_slices_in_tile[0] and the tile size. For example, the number of slices in a tile can be represented by the parameter numSlicesInTile[0].

[0236] 5. For each of the second slices up to the last slice in the picture (including the second slice but excluding the last slice), the width and height of the slice in terms of tile number are explicitly indicated. The starting address of a slice may also be explicitly indicated by the value of the syntax element tile_idx_delta[i], where i is the slice index. If the starting address is not explicitly signaled (for example, if the slices are signaled in an order that allows the starting position of the next slice to be estimated by using the starting position, width, and height of the current slice), the starting address of a slice is estimated via a function. For example, if the slices are signaled in a bitstream in a left-to-right order within the picture, and the horizontal coordinates of the starting address of a slice and the width of the slice are known, the horizontal coordinates of the starting address of the next slice are estimated as the sum of the width of the slice and the starting address of the slice.

[0237] 6. If the size of the nth slice (where n is 2 or greater and less than or equal to the value of a slice in the picture minus 1) is equal to the width of one tile and the height of one tile, and there are more than one CTU row in the tiles contained within the nth slice, the value of the syntax element num_exp_slices_in_tile[n] is signaled, and the value of the syntax element num_exp_slices_in_tile[n] indicates the number of slices contained within that tile.

[0238] 7. For the last slice in a picture, the slice width and height are not explicitly signaled and are estimated according to the number of tiles in the picture width, the number of tiles in the picture height, and the starting address of the last slice. The starting address of the last slice can be explicitly indicated or estimated. The estimation of the width and height of the last slice in a picture can be performed according to the following two formulas, which are taken from section 6.5.1 of VVC Draft 8. slice_width_in_tiles_minus1[i] = NumTileColumns - 1 - tileX slice_height_in_tiles_minus1[i] = NumTileRows - 1 - tileY

[0239] Adding 1 to slice_width_in_tiles_minus1[i] specifies the width of the i-th rectangular slice in terms of tile columns.

[0240] Adding 1 to slice_height_in_tiles_minus1[i] specifies the height of the i-th rectangular slice in terms of tile rows.

[0241] In the above steps, when the start address of the slice is known, it can be estimated, so the width and height of the last slice are not signaled.

[0242] The variables tileX, tileY, NumTileColumns, and NumTileRows in the above equations are explained below.

[0243] Section 6.5.1 of VVC Draft 8 6.5.1 Process of CTB raster scan, tile scan, and sub-picture scan For rectangular slices, the list NumCtusInSlice[i] for i in the range from 0 to num_slices_in_pic_minus1 that specifies the number of CTUs in the i-th slice, the list SliceTopLeftTileIdx[i] for i in the range from 0 to num_slices_in_pic_minus1 that specifies the index of the top-left tile of the slice, and the matrix CtbAddrInSlice[i][j] for i in the range from 0 to num_slices_in_pic_minus1 and j in the range from 0 to NumCtusInSlice[i] - 1 that specifies the picture raster scan address of the j-th CTB in the i-th slice are derived as follows. [Table 4] TIFF0007892931000007.tif74158

[0244] The function AddCtbsToSlice(sliceIdx,startX,stopX,startY,stopY) is specified as follows: [Table 5]

[0245] The above description of signaling for slice start address and slice size within a picture is an example disclosed in VVC Draft 8. Specifically, the description describes the case where rectangular slices are used, the number of slices in each subpicture is not indicated as equal to 1 (when the value of the single_slice_per_subpic_flag syntax element is not equal to 1, and when the value of the single_slice_per_subpic_flag syntax element is equal to 1, each subpicture in a picture consists of only one slice), there are more than one tile in the picture, and the number of CTU rows in a tile is greater than 1. If some of the above parameters are changed, other modes of signaling for slice start address and slice size can be used. For example, if there is only one slice in each subpicture, the slice width and height are not explicitly signaled in the bitstream and are assumed to be equal to the corresponding subpicture width and height, respectively.

[0246] Subsection 6.5.1 of VVC Draft 8 also discloses the scan order of CTUs within slice i, where i is the slice index. The matrix CtbAddrInSlice[i][n], which is the output of this subsection, specifies the CTU scan order within slice i, where n is the CTU index from 0 up to the number of CTUs in slice i. The value of CtbAddrInSlice[i][n] specifies the address of the nth CTU within slice i.

[0247] Typically, the CTU scan order within a slice specifies the order in which the CTUs in the slice are scanned. The steps above in Section 6.5.1 of VVC Draft 8 illustrate an example of how the CTU scan order within a slice is determined, for example, how the matrix CtbAddrInSlice[i][n] is constructed.

[0248] As disclosed in VVC Draft 8, CtbAddrInSlice[i][n] (specifies the CTU scan order within slice i) also specifies the processing order of CTUs within the slice. Specifically, the CTUs of a picture are processed in the following order:

[0249] Slices are indexed by i, and are processed by incrementing i, starting from i equal to 0 and going up to i equal to the number of slices in the picture minus 1. Each CTUn in slice i is processed in ascending order, starting from n equal to 0 and going up to n equal to the number of CTUs in slice i minus 1. The value of CtbAddrInSlice[i][n] specifies the address of the nth CTU in slice i.

[0250] As disclosed in VVC Draft 8, the signaling method is used to indicate the number of slices in each subpicture of a picture. The value of single_slice_per_subpic_flag is used to indicate whether all subpictures of a picture contain only one slice. If the value of single_slice_per_subpic_flag is equal to 1, all subpictures of a picture contain only one slice. Otherwise (the value of single_slice_per_subpic_flag is not equal to 1), the subpictures of a picture may contain more than one slice.

[0251] FIG. 9 shows, as an example, the CTU addresses within a picture and one slice (slice 5, the fifth slice within the picture). According to this example, the values of CtbAddrInSlice are as follows. CtbAddrInSlice[4][0]=27 CtbAddrInSlice[4][1]=28 CtbAddrInSlice[4][2]=29 CtbAddrInSlice[4][3]=30 CtbAddrInSlice[4][4]=37 CtbAddrInSlice[4][5]=38 CtbAddrInSlice[4][6]=39 CtbAddrInSlice[4][7]=40

[0252] The scan order indicates that indexing is performed according to the order in which the index of X within Y is incremented, like the CTU scan order within a tile, where X is a CTU and Y is a tile.

[0253] Processing means decoding or encoding in an encoder or decoder. Thus, the processing order means the order in which X (e.g., a CTU) is processed in an encoder or decoder.

[0254] In VVC Draft 8, when there are more than one tile in a picture, the slices within the picture are signaled as follows.

[0255] 1. The value of the syntax element (explicit indication in the bitstream or estimation from the bitstream) is used to determine the starting tile address of the slice by the number of tiles.

[0256] 2. For each slice except the last slice, the number of tiles included in the slice is signaled. a. If a slice contains only one tile, the number of slices contained in the tile is indicated.

[0257] 3. For the last slice in a picture, if the slice contains at least one complete tile, the number of tiles contained in the slice is estimated.

[0258] In VVC Draft 8, if the size of the last slice in a picture is greater than or equal to one tile (in terms of width and height), the value of the size of the last slice is estimated from the bitstream and not directly coded in the bitstream.

[0259] As described above, the values of slice_width_in_tiles_minus1[i] and slice_height_in_tiles_minus1[i] (indicating the width and height of the i-th slice in terms of the number of tiles, respectively) are coded in the bitstream when i is less than num_slices_in_pic_minus1 (by the for loop "for(i = 0; i < num_slices_in_pic_minus; i++)"). When i is equal to num_slices_in_pic_minus1, for example, for the last slice, the values of the width and height of the slice are not signaled.

[0260] Embodiment 1 · Determine whether the picture is partitioned into more than one tile. · When it is determined that the picture is partitioned into more than one tile (for example, when the condition NumTilesInPic > 1 is true), obtain the number of tiles in the picture width (for example, the number of tiles in the tile row of the picture) NumTileColumns. · Obtain the number of tiles in the picture height (for example, the number of tiles in the tile column of the picture) NumTileRows. This function retrieves the top-left coordinate (SliceTopLeftTileIdx[i]) of the slice in the tile index. The tile index value specifies the index value of the tile in the picture, and the tiles are ordered (indexed) in the raster scan order within the picture. - Obtain the horizontal coordinates of the tile according to the tile index value indicated by the parameter tileX. - Obtain the vertical coordinates of the tile according to the tile index value indicated by the parameter tileY. For each slice in the picture, if the difference between NumTileColumns and tileX is greater than the first threshold, the slice width instruction value is coded into the bitstream. For each slice in the picture, if the difference between NumTileRows and tileY is greater than a second threshold, the value of the slice height indicator is coded into the bitstream.

[0261] The first and second thresholds may be integers greater than 0. In one example, both thresholds may be equal to 1. The thresholds indicate the size threshold in terms of the number of tiles along the horizontal (first threshold) and vertical (second threshold) directions. When the first threshold indicates that the size threshold is equal to one tile, if the difference between tileX and the number of tiles in the picture width is greater than one tile, the slice width indication is included in the bitstream. Note that the thresholds may differ depending on the rule for the starting value of tileX (the value of tileX for the first tile in the picture). For example, if the starting value of tileX is 0, the first threshold may be 1. If the starting value of tileX is 1, the first threshold may be 0.

[0262] In the embodiment, if the last slice contains at least one complete tile, the width and height values ​​of the last slice are also not coded into the bitstream.

[0263] In this embodiment, the value of tileX is obtained according to the modulo operation and the value of NumTileColumns. For example, tileX = tileIdx % NumTileColumns.

[0264] In this embodiment, the value of tileY is obtained according to a division operation and the value of NumTileRows. For example, tileY = tileIdx / NumTileRows.

[0265] In this embodiment, the condition "greater than threshold a" may be realized as "not equal to threshold b". It is also possible to realize this condition as "greater than or equal to threshold c". Typically, threshold a is equal to threshold b, and the third threshold c is equal to threshold a+1.

[0266] One possible implementation of the present invention is shown in Table 3. Table 1, which was part of VVC Draft 8, has been modified.

[0267] In Table 3, rows 10 and 11 describe how to obtain tileX and tileY. The value of SliceTopLeftTileIdx[i] specifies the index (tile index) of the top-left tile in the i-th slice. The tile index is the index of the tile in the picture, and the tiles are ordered in the raster scan order within the picture. For example, as shown in Figure 7, the tile containing CTU0 has tile index 0, the tile containing CTU16 has tile index 1, the tile containing CTU24 has tile index 2, the tile containing CTU44 has tile index 3, the tile containing CTU52 has tile index 4, the tile containing CTU56 has tile index 5, and so on.

[0268] The values ​​of tileX (the horizontal coordinate of the tile in the picture) and tileY (the vertical coordinate of the tile in the picture) are obtained using the following formulas. tileX=SliceTopLeftTileIdx[i]%NumTileColumns tileY=SliceTopLeftTileIdx[i] / NumTileColumns

[0269] In this embodiment, the following condition, "NumTileColumns-tileX>1", is added to the other conditions on line 12. If the condition is not met (NumTileColumns-tileX is not greater than 1), the value of the syntax element slice_width_in_tiles_minus1[i] is not coded directly into the bitstream. Thus, bitrate savings and therefore compression efficiency can be achieved.

[0270] Similarly, on line 14, the following condition, namely "NumTileRows-tileY>1", is added to the other conditions. If the condition is not met (NumTileRows-tileY is not greater than 1), the value of the syntax element slice_height_in_tiles_minus1[i] is not coded directly into the bitstream. Thus, bitrate savings and therefore compression efficiency can be achieved.

[0271] In one example, the threshold is 1, which can be different depending on the implementation method. [Table 6]

[0272] In one embodiment, the values ​​of slice_width_in_tiles_minus1[i] and slice_height_in_tiles_minus1[i] are estimated when they do not exist in the bitstream.

[0273] The following is an example of how the present invention can be implemented as described in Section 6.5.1 of VVC Draft 8.

[0274] For example, the value is estimated to be equal to 0. This can be achieved, for example, in section 6.5.1 of VVC Draft 8, as follows: [Table 7]

[0275] In the above assignment, the value of slice_width_in_tiles_minus1[i] is set to 0 when the difference between NumTileColumns and tileX is greater than 1, which is the same threshold used to determine the presence of slice_width_in_tiles_minus1[i] in the bitstream. In other words, the condition "NumTileColumns-tileX<=thr" determines whether slice_width_in_tiles_minus1[i] exists in the bitstream, and if slice_width_in_tiles_minus1[i] does not exist in the bitstream, its value is estimated (set to 0). If slice_height_in_tiles_minus1[i] does not exist in the bitstream, a similar assignment is made for slice_height_in_tiles_minus1[i].

[0276] The conditions “NumTileRows-tileY=<1” and “NumTileColumns-tileX=<1” in section 6.5.1 of the following VVC Draft 8 are for checking the presence of slice_width_in_tiles_minus1[i] and slice_height_in_tiles_minus1[i] in the bitstream. These may be expressed similarly in other ways, and the important point is that when slice_width_in_tiles_minus1 and slice_height_in_tiles_minus1 do not exist in rows 13 and 15 of Table 3 (the conditions for determining their presence in the bitstream evaluate to false), the values ​​of slice_width_in_tiles_minus1 and slice_height_in_tiles_minus1 should be estimated to be 0.

[0277] The estimated value of slice_height_in_tiles_minus1[i] is 0, which indicates that the height of slice i is equal to one tile.

[0278] When the value of slice_width_in_tiles_minus1[i] is estimated to be 0, this indicates that the width of slice i is equal to one tile.

[0279] slice_height_in_tiles_minus1 and slice_width_in_tiles_minus1 are syntax elements that indicate the size of the slice in each direction. According to embodiments of the present invention, if there is no syntax element in the bitstream relating to the width or height of the slice in terms of the number of tiles, the width or height of the slice is presumed to be one tile.

[0280] Implementation of the present invention in Section 6.5.1 of VVC Draft 8 6.5.1 Processes for CTB raster scanning, tile scanning, and subpicture scanning For a rectangular slice, the following are derived: NumCtusInSlice[i], a list of i in the range from 0 to num_slices_in_pic_minus1 that specifies the number of CTUs in the i-th slice; SliceTopLeftTileIdx[i], a list of i in the range from 0 to num_slices_in_pic_minus1 that specifies the index of the top-left tile of the slice; and CtbAddrInSlice[i][j], a matrix of i in the range from 0 to num_slices_in_pic_minus1 and j in the range from 0 to NumCtusInSlice[i]-1 that specifies the picture raster scan address of the j-th CTB in the i-th slice. [Table 8] TIFF0007892931000012.tif106154

[0281] The function AddCtbsToSlice(sliceIdx,startX,stopX,startY,stopY) is specified as follows: [Table 9]

[0282] As shown in Figure 13, a coding method implemented by a decoding device is disclosed, which includes the following:

[0283] S1301: Get the bitstream of the current picture.

[0284] The bitstream may be obtained via a wireless or wired network. The bitstream 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, Wi-Fi, Bluetooth, LTE, or 5G.

[0285] In the embodiment, the bitstream is a sequence of bits 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).

[0286] In some embodiments, during the decoding process, the decoder reads the bitstream and derives the decoded picture from the bitstream, and during the encoding process, the encoder generates the bitstream.

[0287] Typically, a bitstream contains syntax elements formed by a syntax structure. Syntax elements: elements of data represented in a bitstream.

[0288] Syntax structure: Zero or more syntax elements that exist together in a bitstream in a specified order.

[0289] In a concrete example, a bitstream format specifies the relationship between a network abstraction layer (NAL) unit stream and a byte stream, either of which is called a bitstream.

[0290] A bitstream can be in one of two formats: a NAL unit stream format or a byte stream format. Conceptually, the NAL unit stream format is the more "basic" type. A NAL unit stream format contains a sequence of syntactic structures called NAL units. This sequence is ordered in decryption order. There are constraints imposed on the decryption order (and content) of NAL units within a NAL unit stream.

[0291] A byte stream format can be constructed from NAL units by ordering them in decoding order and prepending on the NAL unit to form a byte stream by adding a start code prefix and zero or more zero-value bytes before each NAL unit. The NAL unit stream format can be extracted from the byte stream format by searching for the position of a unique start code prefix pattern within this stream of bytes.

[0292] This section specifies the relationship between the source picture and the decoded picture, given via a bitstream.

[0293] A video source represented by a bitstream is a sequence of pictures in the decoding order.

[0294] The source picture and the decoded picture each consist of one or more sample arrays. - Luma (Y) only (monochrome) - Luma and two chroma (YCbCr or YCgCo) - Green, blue, and red (also known as GBR or RGB) - Arrays representing other unspecified monochrome or tristimulus color sampling (e.g., also known as YZX, XYZ)

[0295] The variables and terms associated with these arrays are called luma (or L or Y) and chroma, and the two chroma arrays are called Cb and Cr, regardless of the actual color representation used. The actual color representation used can be indicated by a syntax specified by VUI parameters, such as those specified in ITU-T H.SEI|ISO / IEC 23002-7.

[0296] S1302: Gets the number of tiles in the current picture tile row.

[0297] It can be understood that the number of tiles in a tile row is equivalent to the number of tiles in a tile column.

[0298] In one example, the number of tiles in a picture's tile row is represented according to the variable NumTileColumns, which specifies the number of tile columns.

[0299] In one example, the number of tiles in a tile row of the current picture is obtained according to a parameter coded in the picture parameter set of the bitstream. The number of tiles in a tile row of the current picture may be obtained by directly parsing the parameter in the bitstream, or by deriving a value from the parameter.

[0300] S1303: Get the address value of the current picture slice.

[0301] In one example, the slice address value specifies the address of the top-left coordinate of the slice within the tile index.

[0302] In one example, the slice address is the index of the leftmost tile in the top row of tiles in the slice, and the tiles currently included in the picture are indexed according to the order of the raster scan.

[0303] In one example, the address value of a slice is represented according to the variable SliceTopLeftTileIdx[i], where "i" is the slice index.

[0304] For i between 0 and pps_num_slices_in_pic_minus1, SliceTopLeftTileIdx[i] specifies the tile index of the tile containing the first CTU in the slice. pps_num_slices_in_pic_minus1 plus 1 specifies the number of rectangular slices in each picture that references the picture parameter set PPS.

[0305] In one example, the slice address value is obtained according to parameters coded in the bitstream's picture parameter set. The number of tiles in the current picture tile row may be obtained by directly parsing the parameters in the bitstream, or by deriving the value from the parameters.

[0306] S1304: Get the value of tileX according to the slice address value.

[0307] For example, obtaining the value of tileX according to the slice address value includes obtaining the value of tileX according to the slice address value and the number of tiles in the current picture's tile row.

[0308] In one example, the value of tileX is obtained according to a modulo operation between the slice address and the number of tiles in the current picture's tile row.

[0309] In one example, tileX = SliceTopLeftTileIdx[i] % NumTileColumns.

[0310] In one example, the value of tileX represents the horizontal coordinate value.

[0311] S1305: If the difference between the number of tiles in the current picture's tile row and the value of tileX is not equal to the first threshold, parse the slice width instruction value from the current picture's bitstream.

[0312] The first threshold is an integer value, and the first threshold can be 0, 1, 2, ...

[0313] In one example, the slice width instruction is represented as pps_slice_width_in_tiles_minus1[i]. Adding 1 to pps_slice_width_in_tiles_minus1[i] specifies the width of the i-th rectangular slice in units of tile columns. The value of pps_slice_width_in_tiles_minus1[i] may be in the range of 0 or greater and NumTileColumns-1 or less. If it does not exist, the value of pps_slice_width_in_tiles_minus1[i] is assumed to be equal to 0.

[0314] In some cases, the condition "when the difference between the number of tiles in the current picture's tile row and the value of tileX is not equal to a first threshold" can be understood as being equivalent to "when the difference between the number of tiles in the current picture's tile row and the value of the modulo operation between the slice's address and the number of tiles in the current picture's tile row is not equal to a first threshold." Therefore, the value of tileX is not calculated first, but is represented according to the result of the modulo operation between the slice's address and the number of tiles in the current picture's tile row.

[0315] According to embodiments of the present invention, a signaling scheme is disclosed in which only at least two tile rows exist, in which case a syntax element of the slice width is signaled. Thus, bitstream utilization and decoding efficiency are improved.

[0316] In one example, the method further includes the step of setting the slice width indicator to a default value when the difference between the number of tiles in the current picture tile row and the value of tileX is equal to a first threshold. The default value is an integer, and in one example, the default value may be 0 or 1.

[0317] In one example, the default value indicates that the slice width contains one tile column.

[0318] In one example, the method further includes the steps of obtaining the number of tiles in the current picture's tile sequence, obtaining the value of tileY according to the slice address value, and, if the difference between the number of tiles in the current picture's tile sequence and the value of tileY is not equal to a second threshold, parsing an indicator value of the slice height from the current picture's bitstream. The second threshold is an integer value and may be 0, 1, 2...

[0319] It can be understood that the number of tiles in a tile column is equivalent to the number of tile rows.

[0320] In one example, the number of tiles in the current picture's tile row is represented according to the variable NumTileRows, which specifies the number of tile rows.

[0321] In one example, the slice height is expressed according to pps_slice_height_in_tiles_minus1[i]. Adding 1 to pps_slice_height_in_tiles_minus1[i] specifies the height of the i-th rectangular slice in units of tile rows when pps_num_exp_slices_in_tile[i] is equal to 0. The value of pps_slice_height_in_tiles_minus1[i] is assumed to be in the range of 0 or greater and NumTileRows-1 or less.

[0322] In one example, the method further includes the step of setting the slice height indicator to a preset value when the difference between the number of tiles in the current picture tile column and the value of tileY is equal to a second threshold.

[0323] In one example, the step of obtaining the value of tileY according to the slice address value includes the step of obtaining the value of tileY according to the slice address value and the number of tiles in the tile row of the current picture.

[0324] In one implementation, the value of tileY is obtained by performing an integer division operation between the slice address and the number of tiles in the current picture's tile column. For example, tileY = SliceTopLeftTileIdx[i] / NumTileColumns.

[0325] In one example, the value of tileY represents the value of the vertical coordinate. In some examples, the condition "when the difference between the number of tiles in the current picture's tile column and the value of tileY is not equal to a second threshold" can be understood as being equivalent to the condition "when the difference between the number of tiles in the current picture's tile column and the result of an integer division between the slice's address and the number of tiles in the current picture's tile column is not equal to a second threshold." Therefore, the value of tileY is not calculated first, but is represented according to the result of an integer division between the slice's address and the number of tiles in the current picture's tile column.

[0326] In one example, the syntax table for the above embodiment is as follows: [Table 10]

[0327] As shown in Figure 14, a video decoding device 1400 is disclosed, and the device 1400 is, Currently, there is an acquisition module 1401 configured to acquire the bitstream of the picture, and the acquisition module 1401 is configured to acquire the number of tiles in the tile row of the picture and to acquire the address value of the slice of the picture, Computation module 1402 configured to obtain the value of tileX according to the value of the slice address, The system includes a parsing module 1403 configured to parse a slice width instruction value from the bitstream of the current picture when the difference between the number of tiles in the current picture's tile row and the value of tileX is not equal to a first threshold.

[0328] Details of each module may be found by referring to the embodiments and implementations in the embodiments of the method described above.

[0329] Advantages of the present invention Figure 10 illustrates the partitioning of a picture into 96 CTUs, 4 tiles, and 8 slices.

[0330] According to the solutions disclosed in the VVC Draft 8 documentation, the following syntax elements must be coded into the bitstream according to Table 1. • Value equal to 0 num_slices_in_pic_minus1 • tile_idx_delta_present_flag whose value is equal to 1 • Regarding the first slice (meaning the index of i is equal to 0) ○ slice_width_in_tiles_minus1[0] has a value equal to 0 ○ slice_height_in_tiles_minus1[0] has a value equal to 0 ○num_exp_slices_in_tile[0] whose value is equal to 2 ○The number of CTU rows indicates the height of the first slice; a value equal to 0 is exp_slice_height_in_ctus_minus1[0]. Regarding the second slice (i=1): ○The value is equal to 1 exp_slice_height_in_ctus_minus1[1] ○tile_idx_delta[1] whose value is equal to 1 Regarding the third slice (i=2) ○ slice_width_in_tiles_minus1[2] has a value equal to 0 ○ slice_height_in_tiles_minus1[2] has a value equal to 0 ○num_exp_slices_in_tile[2] whose value is equal to 2 ○ The value is equal to 0 exp_slice_height_in_ctus_minus1[2] Regarding the 4th slice (i=3) ○ The value is equal to 1 exp_slice_height_in_ctus_minus1[3] ○tile_idx_delta[3] whose value is equal to 1 Regarding the 5th slice (i=4) ○The value is equal to 0 slice_width_in_tiles_minus1[4] ○The value is equal to 0 slice_height_in_tiles_minus1[4] ○ Value equal to 0 num_exp_slices_in_tile[4] ○tile_idx_delta[4] whose value is equal to 1 Regarding the 6th slice (i=5) ○The value is equal to 0 slice_width_in_tiles_minus1[5] ○The value is equal to 0 slice_height_in_tiles_minus1[5] ○num_exp_slices_in_tile[5] whose value is equal to 3 ○ The value is equal to 1 exp_slice_height_in_ctus_minus1[5] Regarding the 7th slice (i=6) ○ The value is equal to 0 exp_slice_height_in_ctus_minus1[6] Regarding the 8th slice (i=7) ○ The value is equal to 2 exp_slice_height_in_ctus_minus1[7]

[0331] According to embodiments of the present invention, as shown in Table 3, the following syntax elements need to be coded into the bitstream to describe the same picture partition in Figure 10. • Value equal to 0 num_slices_in_pic_minus1 • tile_idx_delta_present_flag whose value is equal to 1 • Regarding the first slice (meaning the index of i is equal to 0) ○ slice_width_in_tiles_minus1[0] has a value equal to 0 ○ slice_height_in_tiles_minus1[0] has a value equal to 0 ○num_exp_slices_in_tile[0] whose value is equal to 2 ○The number of CTU rows indicates the height of the first slice; a value equal to 0 is exp_slice_height_in_ctus_minus1[0]. Regarding the second slice (i=1): ○The value is equal to 1 exp_slice_height_in_ctus_minus1[1] ○tile_idx_delta[1] whose value is equal to 1 Regarding the third slice (i=2) ○ slice_height_in_tiles_minus1[2] has a value equal to 0 ○num_exp_slices_in_tile[2] whose value is equal to 2 ○ The value is equal to 0 exp_slice_height_in_ctus_minus1[2] Regarding the 4th slice (i=3) ○ The value is equal to 1 exp_slice_height_in_ctus_minus1[3] ○tile_idx_delta[3] whose value is equal to 1 Regarding the 5th slice (i=4) ○The value is equal to 0 slice_width_in_tiles_minus1[4] ○ Value equal to 0 num_exp_slices_in_tile[4] ○tile_idx_delta[4] whose value is equal to 1 Regarding the 6th slice (i=5) ○num_exp_slices_in_tile[5] whose value is equal to 3 ○ The value is equal to 1 exp_slice_height_in_ctus_minus1[5] Regarding the 7th slice (i=6) ○ The value is equal to 0 exp_slice_height_in_ctus_minus1[6] Regarding the 8th slice (i=7) ○ The value is equal to 2 exp_slice_height_in_ctus_minus1[7]

[0332] In short, the following syntax elements do not need to be coded into the bitstream. • slice_width_in_tiles_minus1[2] whose value is equal to 0 • slice_height_in_tiles_minus1[4] has a value equal to 0 • slice_width_in_tiles_minus1[5] has a value equal to 0 • slice_height_in_tiles_minus1[5] has a value equal to 0

[0333] The values ​​of these syntax elements are assumed to be equal to 0, according to the following conditions added in section 6.5.1 of VVC Draft 8: [Table 11] TIFF0007892931000016.tif43139

[0334] The following describes the encoding and decoding methods shown in each of the embodiments described above, as well as the application of systems using them.

[0335] 1. A coding method implemented by a decoding device, The current step is to obtain the bitstream of the picture (or frame), The current step is to get the number of tiles in the picture's tile row (for example, the value of NumTileColumns), This step retrieves the address of the current slice (e.g., SliceTopLeftTileIdx[i]), and the current slice is contained within the current picture. The steps are: to obtain the value of the horizontal coordinate (in this example, the horizontal coordinate means the coordinate located on the horizontal axis) (e.g., tileX) according to the current slice address (e.g., SliceTopLeftTileIdx[i]), If the difference between the number of tiles in the current picture's tile row (e.g., the value of NumTileColumns) and the value of the horizontal coordinate (e.g., tileX) is greater than a first threshold (e.g., the first threshold is an integer, which may be 0, 1, 2, etc.), then the steps are to parse the slice width (i.e., the slice width) indicator value from the current picture's bitstream (i.e., the slice width indicator value is coded into the bitstream) and A method that includes this.

[0336] Example 2. The method according to Example 1, further comprising the step of setting the slice width indicator to a default value (for example, the default value may be 0) when the difference between the number of tiles in the current picture tile row (e.g., the value of NumTileColumns) and the value of the horizontal coordinate (e.g., tileX) is less than or equal to a first threshold.

[0337] Example 3. The default value is the method described in Example 2, indicating that the current slice width contains one tile column.

[0338] Example 4. The method according to any one of Examples 1 to 3, wherein the step of obtaining a horizontal coordinate value according to the address value of the current slice includes the step of obtaining a horizontal coordinate value according to the address value of the current slice and the number of tiles in the tile row of the current picture.

[0339] Example 5. The address of the current slice is the index of the leftmost tile in the top row of tiles in the current slice, and the tiles contained in the current picture are indexed according to the raster scan order, as described in any one of Examples 1 through 4.

[0340] Example 6. The method in Example 4 or 5, wherein the horizontal coordinate value is obtained according to a modulo operation between the address value of the current slice and the number of tiles in the tile row of the current picture (e.g., SliceTopLeftTileIdx[i])%NumTileColumns).

[0341] Example 7. The value of the current slice's address (for example, SliceTopLeftTileIdx[i]) specifies the address of the top-left coordinate of the current slice in the tile index.

[0342] Example 8. Steps to obtain the number of tiles in the current picture's tile row (e.g., the value of NumTileRows), The steps are: to obtain the value of the vertical coordinate (in this example, the vertical coordinate means the coordinate located on the vertical axis) (e.g., tileY) according to the current slice address (e.g., SliceTopLeftTileIdx[i]), If the difference between the number of tiles in the current picture's tile row (e.g., the value of NumTileRows) and the value of the vertical coordinate (e.g., tileY) is greater than a second threshold (e.g., the second threshold is an integer, which may be 0, 1, 2, etc.), then the steps are to parse the slice height (i.e., the slice height) indicator value from the current picture's bitstream (i.e., the slice height indicator value is coded into the bitstream) and A method according to any one of Examples 1 to 7, further including the above.

[0343] Example 9. The method according to Example 8, further comprising the step of setting the indicated slice height to a preset value (for example, the preset value may be equal to 0) when the difference between the number of tiles in the current picture's tile row (e.g., the value of NumTileRows) and the value of the vertical coordinate (e.g., tileY) is less than or equal to a second threshold.

[0344] Example 10. The method according to Example 8 or 9, wherein the step of obtaining the vertical coordinate value according to the address value of the current slice includes the step of obtaining the vertical coordinate value according to the address value of the current slice and the number of tiles in the tile column of the current picture.

[0345] Example 11. The vertical coordinate value is obtained by integer division between the address of the current slice and the number of tiles in the tile row of the current picture (e.g., SliceTopLeftTileIdx[i]) / NumTileRows), as in Example 10.

[0346] Example 12. A coding method implemented by a decoding device, The current step is to obtain the bitstream of the picture (or frame), The current step is to get the number of tiles in the picture's tile row (for example, the value of NumTileRows), This step retrieves the address of the current slice (e.g., SliceTopLeftTileIdx[i]), and the current slice is contained within the current picture. The steps are: to obtain the value of the vertical coordinate (in this example, the vertical coordinate means the coordinate located on the vertical axis) (e.g., tileY) according to the current slice address (e.g., SliceTopLeftTileIdx[i]), If the difference between the number of tiles in the current picture's tile row (e.g., the value of NumTileRows) and the value of the vertical coordinate (e.g., tileY) is greater than a second threshold (e.g., the second threshold is an integer, which may be 0, 1, 2, etc.), then the steps are to parse the slice height (i.e., the slice height) indicator value from the current picture's bitstream (i.e., the slice height indicator value is coded into the bitstream) and A method that includes this.

[0347] Example 13. The method of Example 12, further comprising the step of setting the indicated slice height to a preset value (for example, the preset value may be equal to 0) when the difference between the number of tiles in the current picture tile row (e.g., the value of NumTileRows) and the value of the vertical coordinate (e.g., tileY) is less than or equal to a second threshold.

[0348] Example 14. The default value is the method described in Example 13, indicating that the current slice height contains one tile row.

[0349] Example 15. The step of obtaining the vertical coordinate value according to the current slice address value is: The method according to any one of Examples 12 to 14, comprising the step of obtaining the value of the vertical coordinate according to the address value of the current slice and the number of tiles in the tile column of the current picture.

[0350] Example 16. The address of the current slice is the index of the leftmost tile in the top row of tiles in the current slice, and the tiles contained in the current picture are indexed according to the raster scan order, as described in any one of Examples 12 through 15.

[0351] Example 17. The vertical coordinate value is obtained by integer division between the address of the current slice and the number of tiles in the tile row of the current picture (e.g., SliceTopLeftTileIdx[i]) / NumTileRows), as in the method of Example 15 or 16.

[0352] Example 18. The value of the current slice address (e.g., SliceTopLeftTileIdx[i]) specifies the address of the top-left coordinate of the current slice in the tile index, as described in any one of Examples 12 through 17.

[0353] Example 19. Steps to obtain the number of tiles in the current picture's tile row (e.g., the value of NumTileColumns), The steps are: to obtain the value of the horizontal coordinate (in this example, the horizontal coordinate means the coordinate located on the horizontal axis) (e.g., tileX) according to the current slice address (e.g., SliceTopLeftTileIdx[i]), If the difference between the number of tiles in the current picture's tile row (e.g., the value of NumTileColumns) and the value of the horizontal coordinate (e.g., tileX) is greater than a first threshold (e.g., the first threshold is an integer, which may be 0, 1, 2, etc.), then the steps are to parse the slice width (i.e., the slice width threshold is coded into the bitstream) from the current picture's bitstream and The method according to any one of Examples 12 to 18, further including the method described above.

[0354] Example 20. The method according to Example 19, further comprising the step of setting the slice width indicator to a default value (for example, the default value may be equal to 0) when the difference between the number of tiles in the current picture tile row (e.g., the value of NumTileColumns) and the value of the horizontal coordinate (e.g., tileX) is less than or equal to a first threshold.

[0355] Example 21. The method according to Example 19 or 20, wherein the step of obtaining the horizontal coordinate value according to the address value of the current slice includes the step of obtaining the horizontal coordinate value according to the address value of the current slice and the number of tiles in the tile row of the current picture.

[0356] Example 22. The horizontal coordinate value is obtained by a modulo operation between the address of the current slice and the number of tiles in the tile row of the current picture (e.g., SliceTopLeftTileIdx[i])%NumTileColumns).

[0357] Example 23. A coding method implemented by an encoding device, The current step is to get the number of tiles in the picture's tile row (for example, the value of NumTileColumns), This step retrieves the address of the current slice (e.g., SliceTopLeftTileIdx[i]), and the current slice is contained within the current picture. The steps are: to obtain the value of the horizontal coordinate (in this example, the horizontal coordinate means the coordinate located on the horizontal axis) (e.g., tileX) according to the current slice address (e.g., SliceTopLeftTileIdx[i]), The steps are as follows: If the difference between the number of tiles in the current picture's tile row (e.g., the value of NumTileColumns) and the value of the horizontal coordinate (e.g., tileX) is greater than a first threshold (e.g., the first threshold is an integer, which may be 0, 1, 2, etc.), then the steps are to code an indicator value for the slice width of the current picture (i.e., the slice width) (i.e., the slice width indicator value is coded into the bitstream) and obtain the bitstream; A method that includes this.

[0358] Example 24. Steps to obtain the number of tiles in the current picture's tile row (e.g., the value of NumTileRows), The steps are: to obtain the value of the vertical coordinate (in this example, the vertical coordinate means the coordinate located on the vertical axis) (e.g., tileY) according to the current slice address (e.g., SliceTopLeftTileIdx[i]), The steps are as follows: If the difference between the number of tiles in the current picture's tile row (e.g., the value of NumTileRows) and the value of the vertical coordinate (e.g., tileY) is greater than a second threshold (e.g., the second threshold is an integer, which may be 0, 1, 2, etc.), then the steps are to code an indicator value for the current picture's slice height (i.e., the slice height) (i.e., the slice height indicator value is coded into the bitstream) and obtain the bitstream; The method described in Example 23, further including the following.

[0359] Example 25. A coding method implemented by an encoding device, The current step is to get the number of tiles in the picture's tile row (for example, the value of NumTileRows), This step retrieves the address of the current slice (e.g., SliceTopLeftTileIdx[i]), and the current slice is contained within the current picture. The steps are: to obtain the value of the vertical coordinate (in this example, the vertical coordinate means the coordinate located on the vertical axis) (e.g., tileY) according to the current slice address (e.g., SliceTopLeftTileIdx[i]), The steps are as follows: If the difference between the number of tiles in the current picture's tile row (e.g., the value of NumTileRows) and the value of the vertical coordinate (e.g., tileY) is greater than a second threshold (e.g., the second threshold is an integer, which may be 0, 1, 2, etc.), then the steps are to code an indicator value for the current picture's slice height (i.e., the slice height) (i.e., the slice height indicator value is coded into the bitstream) and obtain the bitstream; A method that includes this.

[0360] Example 26. Steps to obtain the number of tiles in the current picture's tile row (e.g., the value of NumTileColumns), The steps are: to obtain the value of the horizontal coordinate (in this example, the horizontal coordinate means the coordinate located on the horizontal axis) (e.g., tileX) according to the current slice address (e.g., SliceTopLeftTileIdx[i]), The steps are as follows: When the difference between the number of tiles in the current picture's tile row (e.g., the value of NumTileColumns) and the value of the horizontal coordinate (e.g., tileX) is greater than a first threshold (e.g., the first threshold is an integer, which may be 0, 1, 2, etc.), the steps are to code an indicator value for the slice width of the current picture (i.e., the slice width) (i.e., the slice width threshold is coded into the bitstream) and obtain the bitstream; The method described in Example 25, further including the method described in Example 25.

[0361] Example 27. A decoder (30) including a processing circuit for performing the method described in any one of Examples 1 to 22.

[0362] Example 28. An encoder including a processing circuit for performing the method described in any one of Examples 23 to 26.

[0363] Example 29. A computer program product that, when executed on a computer or processor, includes program code for performing a method described in any one of the above examples.

[0364] Example 30. A decoder, One or more processors, A non-temporary computer-readable storage medium coupled to a processor and storing a program for execution by the processor, wherein the program, when executed by the processor, configures a decoder to perform the method described in any one of the above examples. A decoder that includes this.

[0365] Example 31. An encoder, One or more processors, A non-temporary computer-readable storage medium coupled to a processor and storing a program for execution by the processor, wherein the program, when executed by the processor, configures a decoder to perform the method described in any one of the above examples. An encoder that includes this.

[0366] Example 32. A non-temporary computer-readable medium that holds program code that, when executed by a computer device, causes the computer device to perform an action in any of the above examples.

[0367] Figure 8 is a block diagram showing a content supply system 3100 for realizing a content distribution service. This content supply system 3100 includes a capture device 3102 and a terminal device 3106, and optionally includes a display 3126. The capture device 3102 communicates with the terminal device 3106 over 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, Wi-Fi, Ethernet, cable, wireless (3G / 4G / 5G), USB, or any combination thereof.

[0368] The capture device 3102 may generate data and encode the data using an encoding method as shown in the above embodiment. Alternatively, the capture device 3102 may distribute the data to a streaming server (not shown in the drawings), which encodes the data and transmits the encoded data to the terminal device 3106. The capture device 3102 includes, but is not limited to, a camera, a smartphone or tablet, 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 as described above. When the data includes video, the video encoder 20 included in the capture device 3102 may actually perform video encoding. When the data includes audio (i.e., voice), the audio encoder included in the capture device 3102 may actually perform audio encoding. In some practical scenarios, the capture device 3102 distributes 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 encoded video data are not multiplexed. The capture device 3102 separately distributes encoded audio data and encoded video data to the terminal device 3106.

[0369] In the content supply system 3100, the terminal device 310 receives and plays back encoded data. The terminal device 3106 may be any device with data reception and recovery capabilities, such as a smartphone or tablet 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, that can decode the above encoded data. For example, the terminal device 3106 may include the destination device 14 as described above. 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.

[0370] In terminal devices with their own displays, such as smartphones or tablets 3108, computers or laptops 3110, network video recorders (NVRs) / digital video decoders (DVRs) 3112, TVs 3114, personal digital assistants (PDAs) 3122, or in-vehicle devices 3124, the terminal device can supply decoded data to its own display. In terminal devices without a display, such as STBs 3116, video conferencing systems 3118, or video surveillance systems 3120, an external display 3126 is made contact with the terminal device to receive and display the decoded data.

[0371] When each device in this system performs encoding or decoding, a picture encoding device or a picture decoding device can be used, as shown in the embodiment described above.

[0372] Figure 9 shows the structure of an example terminal device 3106. After the terminal device 3106 receives a stream from the capture device 3102, the protocol processing unit 3202 analyzes the transmission protocol of the stream. The protocol includes, but is not limited to, Real Time Streaming Protocol (RTSP), Hyper Text Transfer Protocol (HTTP), HTTP Live Streaming Protocol (HLS), MPEG-DASH, Real-time Transport Protocol (RTP), Real Time Messaging Protocol (RTMP), or any combination thereof.

[0373] After the protocol processing 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 described above, in some real-world scenarios, for example in a video conferencing 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 audio decoder 3208 without passing through the demultiplexing unit 3204.

[0374] Through demultiplexing, a video elementary stream (ES), an audio ES, and an optional subtitle are generated. The video decoder 3206, including the video decoder 30 as 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 the synchronization unit 3212. The 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 Figure 9) before being supplied to the synchronization unit 3212. Similarly, the audio frames may be stored in a buffer (not shown in Figure 9) before being supplied to the synchronization unit 3212.

[0375] The synchronization unit 3212 synchronizes video frames and audio frames and supplies video / audio to the video / audio display 3214. For example, the synchronization unit 3212 synchronizes the presentation of video and audio information. The information may be coded in the syntax using timestamps for the presentation of coded audio and visual data and timestamps for the delivery of the data stream itself.

[0376] If subtitles are included in the stream, the subtitle decoder 3210 decodes the subtitles, synchronizes them with the video and audio frames, and supplies the video / audio / subtitle to the video / audio / subtitle display 3216.

[0377] The present invention is not limited to the system described above, and either the picture encoding device or the picture decoding device in the above embodiment can be incorporated into other systems, such as a vehicle system.

[0378] 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 precisely defined, and further operators such as exponential calculations and real-valued division are defined. The numbering and counting rules generally start from 0, for example, "1st" is equivalent to the 0th, "2nd" is equivalent to the 1st, and so on.

[0379] Logical operators The following logical operators are defined as follows: [Table 12]

[0380] Logical operators The following logical operators are defined as follows: x&&y: Boolean "product" of x and y Boolean "union" of x||yx and y ! Boolean logic "negation" If x?y:zx is true or not equal to 0, it evaluates to the value of y; otherwise, it evaluates to the value of z.

[0381] Relational operators The following relational operators are defined as follows: > Larger than >= Above < Less than <= Below == equal != Not equal When a relational operator is applied to a syntax element or variable assigned the value "na" (not applicable), the value "na" is treated as a separate value of the syntax element or variable. The value "na" is considered not to be equal to any other value.

[0382] Bitwise operators The following bitwise operators are defined as follows: & Bitwise "product". When operating on integer arguments, the operation is performed on the two's complement representation of the integer values. When operating on a binary argument that contains fewer bits than the other argument, the shorter argument is extended by adding higher-order bits equal to 0. | Bitwise "sum". When operating on integer arguments, the operation is performed on the two's complement representation of the integer values. When operating on a binary argument that contains fewer bits than the other argument, the shorter argument is extended by adding higher-order bits equal to 0. ^ Bitwise "exclusive sum". When operating on integer arguments, the operation is performed on the two's complement representation of the integer values. When operating on a binary argument that contains fewer bits than the other argument, the shorter argument is extended by adding higher-order bits equal to 0. x>>y Arithmetic right shift of the two's complement integer representation of x by y binary digits. 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 a value equal to the MSB of x before the shift operation. x<<y Arithmetic left shift of the two's complement integer representation of x by y binary digits. 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.

[0383] Assignment operators The following assignment operators are defined as follows. = Assignment operator ++ Increment. That is, x++ is equal to x=x+1. When used in an array index, it is evaluated to the value of the variable before the increment operation. -- Decrement. That is, x-- is equal to x=x-1. When used in an array index, it is evaluated to the value of the variable before the decrement operation. += increments by the specified amount. That is, x+=3 is equal to x=x+3, and x+=(-3) is equal to x=x+(-3). -= Decrement by the specified amount. That is, x-=3 is equal to x=x-3, and x-=(-3) is equal to x=x-(-3).

[0384] Range notation The following notation is used to specify a range of values. x = y . . zx takes integer values ​​between y and z (inclusive), where x, y, and z are integers, and z is greater than y.

[0385] Mathematical functions The following mathematical functions are defined.

number

number

number

number

number

number

number

[0386] Order of operations When the precedence of an expression is not explicitly indicated by the use of parentheses, the following rules apply: - Higher-priority operations are evaluated before any lower-priority operations. - Operations with the same priority are evaluated sequentially from left to right.

[0387] The table below specifies the order of operations from highest to lowest, with higher positions in the table indicating higher priority.

[0388] For operators also used in the C programming language, the precedence used herein is the same as that used in the C programming language. [Table 13]

[0389] Text description of logical operations In text, the following format: if (condition 0) Statement 0 else(condition 1) Statement 1 ... else / *Reference notes regarding the remaining conditions* / statement n Statements of logical operations that are mathematically described may also be written in the following manner. ...as follows / ...the following applies: -If condition 0, statement 0 - If not, and condition 1 is true, then statement 1 -... -Otherwise (see note regarding the remaining conditions), statement n Each "if..., otherwise, if..., otherwise..." statement in the text is introduced by "if..." followed immediately by "...as follows" or "...as follows." The final condition in "if..., otherwise, if..., otherwise..." is always "...if..., otherwise...." Alternating "if..., otherwise, if..., otherwise..." statements can be identified by matching them with "...as follows" or "...as follows" ending with "...if..., otherwise...."

[0390] In text, the following format: if(condition 0a &&condition 0b) Statement 0 else if(condition 1a||condition 1b) Statement 1 ... else statement n Statements of logical operations that are mathematically described may also be written in the following manner. ...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

[0391] In text, the following format: if (condition 0) Statement 0 if (condition 1) Statement 1 Statements of logical operations that are mathematically described may also be written in the following manner. When condition 0, statement 0 When condition 1 is met, statement 1

[0392] While embodiments of the present invention have been described primarily in terms of video coding, it should be noted that embodiments of the coding system 10, encoder 20, and decoder 30 (and correspondingly system 10), as well as other embodiments described herein, may also be configured for still image picture processing or coding, i.e., processing or coding of individual pictures independent of any preceding or consecutive pictures, as in video coding. Generally, when picture processing coding is limited to a single picture 17, only the interpretation units 244 (encoder) and 344 (decoder) may be available. All other functions (also called tools or techniques) of the video encoder 20 and video decoder 30 may be used equivalently for still image picture processing, such as residual calculation 204 / 304, transformation 206, quantization 208, inverse quantization 210 / 310, (inverse) transformation 212 / 312, partitioning 262 / 362, intra prediction 254 / 354, and / or loop filtering 220, 320, as well as entropy coding 270 and entropy decoding 304.

[0393] For example, embodiments of the encoder 20 and decoder 30, and the functions described herein with respect to the encoder 20 and decoder 30, may be implemented in hardware, software, firmware, or a combination thereof. If implemented in software, the functions may be stored as one or more instructions or codes on a computer-readable medium or transmitted over a communication medium and executed by a hardware-based processing unit. The computer-readable medium may include a computer-readable storage medium corresponding to a tangible medium such as a data storage medium, or a communication medium including, for example, any medium that facilitates the transfer of computer programs from one location to another according to a communication protocol. Thus, the computer-readable medium may generally correspond to (1) a non-transient tangible computer-readable storage medium, or (2) a communication medium such as a signal or carrier wave. The data storage medium may be any available medium accessible by one or more computers or one or more processors to retrieve instructions, codes and / or data structures for the implementation of the technology described herein. The computer program product may include a computer-readable medium.

[0394] Such computer-readable storage media may include, but are not limited to, computer-readable storage media, such as 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 is accessible by a computer. Any connection is also appropriately called 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, and microwave, then coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of a medium. However, it should be understood that computer-readable storage media and data storage media do not include connections, carriers, signals, or other temporary media, but instead refer to non-temporary tangible storage media. When used herein, "disk" and "disc" include compact discs (CDs), laser discs, optical discs, digital versatile discs (DVDs), floppy discs, and Blu-ray discs, where a "disk" typically reproduces data magnetically, and a "disc" reproduces data optically using a laser. Any combination of the above should also be included in the scope of computer-readable media.

[0395] Instructions may be executed by one or more processors, such as digital signal processors (DSPs), general-purpose microprocessors, application-specific integrated circuits (ASICs), field-programmable logic arrays (FPGAs), or other equivalent integrated or discrete logic circuits. Therefore, when used herein, the term "processor" may refer to any of the above structures or any other structure suitable for the implementation of the technology described herein. Furthermore, in some embodiments, the functions described herein may be provided within dedicated hardware and / or software modules configured for encoding and decoding, or incorporated into a combined codec. The technology may also be fully implemented in one or more circuits or logic elements.

[0396] The technology of this disclosure may be implemented in a wide range of devices or apparatus, including wireless handsets, integrated circuits (ICs), or sets of ICs (e.g., chipsets). Various components, modules, or units are described in this disclosure to highlight the functional aspects of devices configured to perform the technology of this disclosure, but implementation by different hardware units is not necessarily required. Rather, as described above, various units may be coupled to a codec hardware unit in combination with appropriate software and / or firmware, or they may be provided by a collection of interoperable hardware units including one or more processors as described above.

Claims

1. A decryption method for a decryption device, The steps include: obtaining the bitstream of the current picture, the bitstream containing a no_pic_partition_flag, and the value of the no_pic_partition_flag being used to indicate whether the current picture is partitioned into slices or tiles; When the value of no_pic_partition_flag indicates that the current picture is partitioned into slices or tiles, The steps include obtaining the number of tiles in the tile row of the current picture, The steps include obtaining the address value of the slice of the current picture, The step of obtaining the value of tileX according to the value of the address of the slice, wherein the value of tileX represents the horizontal coordinate of the leftmost tile in the topmost tile row of the slice in units of tile columns, When the difference between the number of tiles in the tile row of the current picture and the value of tileX is not equal to a first threshold, the steps are to parse the indicated slice width of the slice from the bitstream of the current picture. A method that includes this.

2. The method according to claim 1, further comprising the step of setting the indicated value of the slice width to a default value when the difference between the number of tiles in the tile row of the current picture and the value of tileX is equal to the first threshold.

3. The method according to claim 2, wherein the default value indicates that the width of the slice includes one tile row.

4. The step of obtaining the value of tileX according to the value of the address of the slice is: The method according to claim 1, comprising the step of obtaining the value of tileX according to the value of the address of the slice and the number of tiles in the tile row of the current picture.

5. The method according to claim 4, wherein the value of tileX is obtained according to a modulo operation between the value of the address of the slice and the number of tiles in the tile row of the current picture.

6. A coding method for a coding device, The step of determining the value of no_pic_partition_flag, where no_pic_partition_flag is used to indicate whether the picture is currently partitioned into slices or tiles, and the step of When the aforementioned picture is partitioned into slices or tiles, The steps include obtaining the number of tiles in the tile row of the current picture, The steps include obtaining the address value of the slice of the current picture, The step of obtaining the value of tileX according to the value of the address of the slice, wherein the value of tileX represents the horizontal coordinate of the leftmost tile in the topmost tile row of the slice in units of tile columns, The steps include: obtaining a bitstream by encoding the specified slice width of the slice and the no_pic_partition_flag, wherein the specified value is encoded in the bitstream when the difference between the number of tiles in the tile row of the current picture and the value of tileX is not equal to a first threshold; and A method that includes this.

7. The method according to claim 6, further comprising the step of setting the indicated value of the slice width to a default value when the difference between the number of tiles in the tile row of the current picture and the value of tileX is equal to the first threshold.

8. The method according to claim 7, wherein the default value indicates that the width of the slice includes one tile row.

9. The step of obtaining the value of tileX according to the value of the address of the slice is: The method according to claim 6, comprising the step of obtaining the value of tileX according to the value of the address of the slice and the number of tiles in the tile row of the current picture.

10. The method according to claim 9, wherein the value of tileX is obtained according to a modulo operation between the value of the address of the slice and the number of tiles in the tile row of the current picture.

11. A decoder including a processing circuit for performing the method according to any one of claims 1 to 5.

12. An encoder comprising a processing circuit for performing the method according to any one of claims 6 to 10.

13. A method for storing a bitstream of video data, Steps include generating the bitstream, wherein the bitstream includes no_pic_partition_flag, the value of which is used to indicate whether the current picture is partitioned into slices or tiles, and if the value of which is no_pic_partition_flag indicates that the current picture is partitioned into slices or tiles, and the difference between the number of tiles in the tile row of the current picture and the value of tileX is not equal to a first threshold, the bitstream further includes an indication value of the slice width of the slice of the current picture, the value of which is obtained according to the address value of the slice, and the value of which is indicated by the horizontal coordinate of the leftmost tile in the top tile row of the slice in units of tile columns, The steps include storing the bitstream in a storage medium and A method that includes this.

14. A method for transmitting a bitstream of video data, Steps include: generating a bitstream and storing it in a storage medium, wherein the bitstream includes a no_pic_partition_flag, the value of which is used to indicate whether the current picture is partitioned into slices or tiles, and if the value of which is a no_pic_partition_flag indicates that the current picture is partitioned into slices or tiles, and the difference between the number of tiles in the tile row of the current picture and the value of tileX is not equal to a first threshold, the bitstream further includes an indicator value for the slice width of the slice of the current picture, the value of which is obtained according to the address value of the slice, and the value of which is indicated by the horizontal coordinate of the leftmost tile in the top tile row of the slice in units of tile columns; The steps of transmitting the bitstream and A method that includes this.

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