Method, apparatus and medium for video processing

Abstract

An embodiment of the present disclosure provides a scheme for video processing. A video processing method is proposed. The method includes: performing a conversion between a current video block of the video and a bitstream of the video based on a general constraint information (GCI) of the video, the GCI including one or more syntax elements, where each of the one or more syntax elements is not present in the bitstream and has a value equal to a first predetermined value. Compared with the conventional scheme, the proposed method has an advantage of improving coding efficiency.

Description

[Technical field]

[0001] This application claims the benefit of priority to U.S. Provisional Application No. 63 / 281,381, filed November 19, 2021, the entire disclosure of which is incorporated herein by reference.

[0002] FIELD OF THE DISCLOSURE Embodiments of the present disclosure relate generally to video coding techniques, and more particularly, to signaling VVC range extension general constraint information flags. [Background technology]

[0003] Video coding standards have evolved primarily through the development of well-known ITU-T and ISO / IEC standards. ITU- created H.261 and H.263, ISO / IEC created MPEG-1 and MPEG-4 Visual, and the two organizations jointly created H.262 / MPEG-2 Video, H.264 / MPEG-4 Advanced Video Coding (AVC), and H.265 / HEVC standards. Since H.262, video coding standards have been based on a hybrid video coding structure in which temporal prediction plus transform coding is utilized. To explore future video coding technologies beyond HEVC, the Joint Video Exploration Team (JVET) was jointly established by VCEG and MPEG in 2015. Since then, many new methods have been adopted by JVET and incorporated into a reference software named Joint Exploration Model (JEM). Later, JVET was renamed to JVET when the VVC project was officially launched. VVC is a new coding standard that aims to reduce bitrate by 50% compared to HEVC.

[0004] The VVC standard and associated Versatile Supplemental Enhancement Information (VSEI) standard for coded video bitstreams are designed to be used in the widest range of applications, including both traditional uses such as television broadcast, videoconferencing, or playback from storage media, and newer, more advanced uses such as adaptive bitrate streaming, video region extraction, content composition and combining from multiple coded video bitstreams, multiview video, scalable layered coding, and viewport adaptive 360-degree immersive media. The latest draft amendments to the VVC standard include the specification of range extension profiles and other aspects. Summary of the Invention

[0005] The embodiments of the present disclosure provide a solution for video processing.

[0006] In a first aspect, a video processing method is proposed, comprising the steps of: performing a conversion between a current video block of the video and a bitstream of the video based on a general constraint information (GCI) of the video, the GCI comprising: a first syntax element indicating whether all pictures in one or more output layer sets (OLS) are recovery point pictures or intra random access point (IRAP) pictures; a second syntax element indicating whether extended dynamic range is used for the scaling and transformation process and binarization of the syntax elements abs_remaining and dec_abs_level for all pictures in one or more OLSs; a third syntax element indicating whether the slice parameters used for the syntax structure residual_ts_coding in the current slice are indicated in a syntax structure slice_header pointing to a sequence parameter set (SPS) for all pictures in one or more OLSs; a fourth syntax element indicating whether an alternative Rice parameter derivation is used for the binarization of syntax elements abs_remaining and dec_abs_level for all pictures in one or more OLSs, a fifth syntax element indicating whether a Rice parameter derivation for the binarization of syntax elements abs_remaining and dec_abs_level is initialized at the beginning of each TU using statistics accumulated from a previous transform unit (TU) for all pictures in one or more OLSs, or a sixth syntax element indicating whether a syntax element sh_reverse_last_sig_coeff_flag is present in a syntax structure slice_header pointing to the SPS for all pictures in one or more OLSs, wherein each of the one or more syntax elements is not present in the bitstream and has a value equal to a first predetermined value.

[0007] According to the method according to the first aspect of the present disclosure, the value of each of the six GCI syntax elements is inferred to be equal to a predefined value (e.g., 0) when it is not present in the bitstream. Compared with the conventional solution in which the values ​​of such GCI syntax elements are not inferred, the proposed method has the advantage that the values ​​of these GCI syntax elements can be obtained even when they are not present in the bitstream, thereby ensuring a uniform process of video processing and improving coding efficiency.

[0008] In a second aspect, an apparatus for processing video data is proposed, said apparatus for processing video data comprising a processor and a non-transitory memory with instructions that, when executed by the processor, cause the processor to perform a method according to the first aspect of the present disclosure.

[0009] In a third aspect, a non-transitory computer-readable storage medium is proposed, said non-transitory computer-readable storage medium storing instructions for causing a processor to perform the method according to the first aspect of the present disclosure.

[0010] In a fourth aspect, another non-transitory computer-readable recording medium is proposed. The non-transitory computer-readable recording medium stores a bitstream of a video generated by a method executed by a video processing device, the method comprising the steps of: performing a conversion between a current video block of the video and the bitstream of the video based on a general constraint information (GCI) of the video, the GCI including: a first syntax element indicating whether all pictures in one or more output layer sets (OLS) are recovery point pictures or intra random access point (IRAP) pictures; a second syntax element indicating whether extended dynamic range is used for the scaling and transformation process and binarization of syntax elements abs_remaining and dec_abs_level for all pictures in one or more OLS; a third syntax element indicating whether the slice parameters used for the syntax structure residual_ts_coding in the current slice are indicated in a syntax structure slice_header pointing to a sequence parameter set (SPS) for all pictures in one or more OLS; a fourth syntax element indicating whether an alternative Rice parameter derivation is used for the binarization of syntax elements abs_remaining and dec_abs_level for all pictures in one or more OLSs, a fifth syntax element indicating whether a Rice parameter derivation for the binarization of syntax elements abs_remaining and dec_abs_level is initialized at the beginning of each TU using statistics accumulated from a previous transform unit (TU) for all pictures in one or more OLSs, or a sixth syntax element indicating whether a syntax element sh_reverse_last_sig_coeff_flag is present in a syntax structure slice_header pointing to the SPS for all pictures in one or more OLSs, wherein each of the one or more syntax elements is not present in the bitstream and has a value equal to a first predetermined value.

[0011] In a fifth aspect, a method for storing a bitstream of a video is proposed, comprising the steps of: performing a conversion between a current video block of the video and the bitstream of the video based on a General Constraint Information (GCI) of the video, the GCI comprising: a first syntax element indicating whether all pictures in one or more Output Layer Sets (OLS) are recovery point pictures or Intra Random Access Point (IRAP) pictures; a second syntax element indicating whether extended dynamic range is used for the scaling and transformation process and binarization of the syntax elements abs_remaining and dec_abs_level for all pictures in one or more OLSs; a third syntax element indicating whether the slice parameters used for the syntax structure residual_ts_coding in the current slice are indicated in a syntax structure slice_header pointing to a Sequence Parameter Set (SPS) for all pictures in one or more OLSs; a fourth syntax element indicating whether an alternative Rice parameter derivation is used for the binarization of syntax elements abs_remaining and dec_abs_level, a fifth syntax element indicating whether, for all pictures in one or more OLSs, a Rice parameter derivation for the binarization of syntax elements abs_remaining and dec_abs_level is initialized at the beginning of each TU using statistics accumulated from previous transform units (TUs), or a sixth syntax element indicating, for all pictures in one or more OLSs, whether a syntax element sh_reverse_last_sig_coeff_flag is present in a syntax structure slice_header pointing to the SPS, and storing the bitstream in a non-transitory computer-readable recording medium, wherein each of the one or more syntax elements is not present in the bitstream and has a value equal to a first predetermined value.

[0012] This description is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This description is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. [Brief description of the drawings]

[0013] The above and other objects, features, and advantages of exemplary embodiments of the present disclosure will become more apparent through the following detailed description taken in conjunction with the accompanying drawings, in which like reference numerals generally refer to like components.

[0014] [Figure 1] 1 shows a block diagram illustrating an example video coding system according to some embodiments of the present disclosure.

[0015] [Diagram 2] 1 shows a block diagram illustrating a first exemplary video encoder according to some embodiments of the present disclosure.

[0016] [Diagram 3] 1 shows a block diagram illustrating an example video decoder according to some embodiments of the present disclosure.

[0017] [Figure 4] 1 illustrates a flowchart of a video processing method according to some embodiments of the present disclosure.

[0018] [Diagram 5] FIG. 1 illustrates a block diagram of a computing device capable of implementing various embodiments of the present disclosure.

[0019] Throughout the drawings, the same or similar reference numbers typically refer to the same or similar elements. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Next, the principles of the present disclosure will be described with reference to some embodiments. It should be understood that these embodiments are provided for illustrative purposes only, to help those skilled in the art understand and embody the present disclosure, and do not imply any limitations on the scope of the present disclosure. The disclosure described herein can be embodied in various ways other than those described below.

[0021] In the following description and claims, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0022] References in this disclosure to "one embodiment," "one embodiment," "exemplary embodiment," and the like indicate that the described embodiment may include a particular feature, structure, or characteristic, but not all embodiments necessarily include the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. Furthermore, when a particular feature, structure, or characteristic is described in connection with an exemplary embodiment, it is noted that it is within the knowledge of one of ordinary skill in the art to affect such feature, structure, or characteristic in connection with other embodiments, whether or not explicitly described.

[0023] Terms such as "first" and "second" may be used herein to describe various elements, but it should be understood that these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element, without departing from the scope of the exemplary embodiments. As used herein, the term "and / or" includes any and all combinations of one or more of the listed terms.

[0024] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly dictates otherwise. It will be further understood that the terms "comprise," "comprising," "having," "having," "containing," and / or "including," as used herein, specify the presence of stated features, elements, and / or components, etc., but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof.

[0025] Example Environment 1 is a block diagram illustrating an example video coding system 100 that may utilize techniques of this disclosure. As shown, video coding system 100 may include a source device 110 and a destination device 120. Source device 110 may also be referred to as a video encoding device, and destination device 120 may also be referred to as a video decoding device. In operation, source device 110 may be configured to generate encoded video data, and destination device 120 may be configured to decode the encoded video data generated by source device 110. Source device 110 may include a video source 112, a video encoder 114, and an input / output (I / O) interface 116.

[0026] Video source 112 may include sources such as video capture devices. Examples of video capture devices include, but are not limited to, an interface that receives video data from a video content provider, a computer graphics system that generates video data, and / or combinations thereof.

[0027] The video data may include one or more pictures. The video encoder 114 encodes the video data from the video source 112 to generate a bitstream. The bitstream may include a series of bits forming a coded representation of the video data. The bitstream may include coded pictures and associated data. A coded picture is a coded representation of a picture. The associated data may include sequence parameter sets, picture parameter sets, and other syntax structures. The I / O interface 116 may include a modulator / demodulator and / or a transmitter. The coded video data may be transmitted directly to the destination device 120 through the network 130A via the I / O interface 116. The coded video data may be stored in a storage medium / server 130B for access by the destination device 120.

[0028] Destination device 120 may include an I / O interface 126, a video decoder 124, and a display device 122. I / O interface 126 may include a receiver and / or a modem. I / O interface 126 may obtain encoded video data from source device 110 or storage medium / server 130B. Video decoder 124 may decode the encoded video data. Display device 122 may display the decoded video data to a user. Display device 122 may be integrated with destination device 120 or may be external to destination device 120 configured to interface with an external display device.

[0029] Video encoder 114 and video decoder 124 may operate according to a video compression standard, such as the High Efficiency Video Coding (HEVC) standard, the Versatile Video Coding (VVC) standard, and other current and / or future standards.

[0030] FIG. 2 is a block diagram illustrating an example of a video encoder 200, which may be an example of the video encoder 114 in the system 100 shown in FIG. 1, according to some embodiments of the disclosure.

[0031] Video encoder 200 may be configured to embody any or all of the techniques of this disclosure. In the example of FIG. 2, video encoder 200 includes multiple functional components. The techniques described in this disclosure may be shared among various components of video encoder 200. In some examples, a processor may be configured to perform any or all of the techniques described in this disclosure.

[0032] In some embodiments, the video encoder 200 may include a division unit 201, a prediction unit 202, which may include a mode selection unit 203, a motion estimation unit 204, a motion compensation unit 205, and an intra prediction unit 206, a residual generation unit 207, a transform unit 208, a quantization unit 209, an inverse quantization unit 210, an inverse transform unit 211, a reconstruction unit 212, a buffer 213, and an entropy coding unit 214.

[0033] In other examples, video encoder 200 may include more, fewer, or different functional components. In one example, prediction unit 202 may include an intra block copy (IBC) unit. The IBC unit may perform prediction in an IBC mode, where at least one reference picture is the picture in which the current video block is located.

[0034] Furthermore, some components, such as the motion estimation unit 204 and the motion compensation unit 205, may be integrated but are depicted separately in the example of FIG. 2 for illustrative purposes.

[0035] Division unit 201 may divide a picture into one or more video blocks. Video encoder 200 and video decoder 300 may support a variety of video block sizes.

[0036] The mode selection unit 203 may, for example, select one of intra or inter coding modes based on the error result, provide the resulting intra-coded or inter-coded block to the residual generation unit 207 to generate residual block data, and provide the resulting intra-coded or inter-coded block to the reconstruction unit 212 to reconstruct the coded block and use it as a reference picture. In some examples, the mode selection unit 203 may select a combined intra- and inter-prediction (CIIP) mode, in which prediction is based on an inter prediction signal and an intra prediction signal. In the case of inter prediction, the mode selection unit 203 may select a resolution of the motion vector of the block (e.g., sub-pixel or integer pixel accuracy).

[0037] To perform inter prediction on the current video block, motion estimation unit 204 may generate motion information for the current video block by comparing one or more reference frames from buffer 213 with the current video block. Motion compensation unit 205 may determine a prediction video block for the current video block based on the motion information and decoded samples of pictures from buffer 213 other than the picture associated with the current video block.

[0038] Motion estimation unit 204 and motion compensation unit 205 may perform different operations on a current video block depending on whether the current video block is in an I slice, a P slice, or a B slice, for example. As used herein, an "I slice" may refer to a portion of a picture composed of macroblocks, all of which are based on macroblocks in the same picture. Additionally, as used herein, in some aspects, a "P slice" and a "B slice" may refer to a portion of a picture composed of macroblocks that are independent of macroblocks in the same picture.

[0039] In some examples, motion estimation unit 204 may perform unidirectional prediction on the current video block, and motion estimation unit 204 may look for a reference picture in list 0 or list 1 for a reference video block of the current video block. Motion estimation unit 204 may then generate a reference index indicating a reference picture in list 0 or list 1 that contains the reference video block, and a motion vector indicating a spatial displacement between the current video block and the reference video block. Motion estimation unit 204 may output the reference index, the prediction direction indicator, and the motion vector as motion information for the current video block. Motion compensation unit 205 may generate a predictive video block for the current video block based on the reference video block indicated by the motion information of the current video block.

[0040] Alternatively, in other examples, motion estimation unit 204 may perform bidirectional prediction on the current video block. Motion estimation unit 204 may look for a reference picture in list 0 for a reference video block of the current video block, and may look for a reference picture in list 1 for another reference video block of the current video block. Motion estimation unit 204 may then generate a reference index indicating the reference picture in list 0 and list 1 that contains the reference video block, and a motion vector indicating a spatial displacement between the reference video block and the current video block. Motion estimation unit 204 may output the reference index and the motion vector of the current video block as motion information of the current video block. Motion compensation unit 205 may generate a predictive video block for the current video block based on the reference video block indicated by the motion information of the current video block.

[0041] In some examples, motion estimation unit 204 may output a full set of motion information for the decoding process of the decoder. Alternatively, in some embodiments, motion estimation unit 204 may signal the motion information of the current video block with reference to the motion information of another video block. For example, motion estimation unit 204 may determine that the motion information of the current video block is sufficiently similar to the motion information of a neighboring video block.

[0042] In one example, motion estimation unit 204 may indicate, in a syntax structure associated with the current video block, a value that indicates to video decoder 300 that the current video block has the same motion information as another video block.

[0043] In another example, motion estimation unit 204 may identify another video block and a motion vector differential (MVD) in a syntax structure associated with the current video block. The motion vector differential indicates a difference between the motion vector of the current video block and the motion vector of the indicated video block. Video decoder 300 may determine the motion vector of the current video block using the motion vector and the motion vector differential of the indicated video block.

[0044] As discussed above, video encoder 200 may predictively signal motion vectors. Two examples of predictive signaling techniques that may be implemented by video encoder 200 include advanced motion vector prediction (AMVP) and merge mode signaling.

[0045] Intra prediction unit 206 may perform intra prediction on the current video block. When intra prediction unit 206 performs intra prediction on the current video block, intra prediction unit 206 may generate predictive data for the current video block based on decoded samples of other video blocks in the same picture. The predictive data for the current video block may include a predicted video block and various syntax elements.

[0046] Residual generation unit 207 may generate residual data for the current video block by subtracting (e.g., as indicated by a minus sign) the prediction video block of the current video block from the current video block. The residual data for the current video block may include residual video blocks that correspond to different sample components of the samples in the current video block.

[0047] In other examples, such as in skip mode, residual data for the current video block may not be present, and residual generation unit 207 may not perform the subtraction operation.

[0048] Transform processing unit 208 may apply one or more transforms to the residual video block associated with the current video block to generate one or more transform coefficient video blocks for the current video block.

[0049] After transform processing unit 208 generates the transform coefficient video block associated with the current video block, quantization unit 209 may quantize the transform coefficient video block associated with the current video block based on one or more quantization parameter (QP) values ​​associated with the current video block.

[0050] Inverse quantization unit 210 and inverse transform unit 211 may apply inverse quantization and inverse transform, respectively, to the transform coefficient video block to reconstruct a residual video block from the transform coefficient video block. Reconstruction unit 212 may add the reconstructed residual video block to corresponding samples from one or more prediction video blocks generated by prediction unit 202 to generate a reconstructed video block associated with the current video block for storage in buffer 213.

[0051] After reconstruction unit 212 reconstructs the video blocks, a loop filtering operation may be performed to reduce video blocking artifacts in the video blocks.

[0052] Entropy encoding unit 214 may receive data from other functional components of video encoder 200. Once entropy encoding unit 214 receives the data, it may perform one or more entropy encoding operations to generate entropy encoded data and output a bitstream including the entropy encoded data.

[0053] FIG. 3 is a block diagram illustrating an example of a video decoder 300, which may be an example of the video decoder 124 in the system 100 shown in FIG. 1, according to some embodiments of the disclosure.

[0054] The video decoder 300 may be configured to perform any or all of the techniques of this disclosure. In the example of FIG. 3, the video decoder 300 includes multiple functional components. The techniques described in this disclosure may be shared among various components of the video decoder 300. In some examples, a processor may be configured to perform any or all of the techniques described in this disclosure.

[0055] 3, the video decoder 300 includes an entropy decoding unit 301, a motion compensation unit 302, an intra prediction unit 303, an inverse quantization unit 304, an inverse transform unit 305, a reconstruction unit 306, and a buffer 307. The video decoder 300 may, in some examples, perform a decoding pass that is generally inverse to the encoding pass described with respect to the video encoder 200.

[0056] The entropy decoding unit 301 may retrieve an encoded bitstream. The encoded bitstream may include entropy coded video data (e.g., coded blocks of video data). The entropy decoding unit 301 may decode the entropy coded video data, from which the motion compensation unit 302 may determine motion information including motion vectors, motion vector precision, reference picture list indexes, and other motion information. The motion compensation unit 302 may determine such information, for example, by performing AMVP and merge mode. AMVP is used and includes derivation of some most likely candidates based on data from neighboring PB and reference pictures. The motion information typically includes horizontal and vertical motion vector displacement values, one or two reference picture indexes, and, for prediction regions in B slices, identification of which reference picture list is associated with each index. As used herein, in some aspects, "merge mode" may refer to deriving motion information from spatially or temporally neighboring blocks.

[0057] The motion compensation unit 302 may generate a motion compensated block, possibly performing interpolation based on an interpolation filter. An identifier of the interpolation filter used with sub-pixel precision may be included in the syntax element.

[0058] The motion compensation unit 302 may calculate interpolated values ​​for sub-integer pixels of the reference block using an interpolation filter used by the video encoder 200 during encoding of the video block. The motion compensation unit 302 may determine the interpolation filter used by the video encoder 200 according to the received syntax information and generate a predictive block using the interpolation filter.

[0059] The motion compensation unit 302 may use at least a portion of the syntactic information to determine the size of blocks used to code frames and / or slices of the coded video sequence, partition information describing how each macroblock of a picture of the coded video sequence is divided, a mode indicating how each partition is coded, one or more reference frames (and reference frame lists) for each inter-encoded block, and other information for decoding the coded video sequence. As used herein, in some aspects, a "slice" may refer to a data structure that can be decoded independently from other slices of the same picture for entropy coding, signal prediction, and residual signal reconstruction. A slice can be either an entire picture or a region of a picture.

[0060] The intra prediction unit 303 may form a prediction block from spatially neighboring blocks, e.g., using an intra prediction mode received in the bitstream. The inverse quantization unit 304 inverse quantizes, or dequantizes, the quantized video block coefficients provided in the bitstream and decoded by the entropy decoding unit 301. The inverse transform unit 305 applies an inverse transform.

[0061] The reconstruction unit 306 may obtain a decoded block, for example, by adding the residual block and a corresponding prediction block generated by the motion compensation unit 302 or the intra prediction unit 303. Optionally, a deblocking filter may be applied to filter the decoded block to remove blockiness artifacts. The decoded video block is then stored in a buffer 307, which provides reference blocks for subsequent motion compensation / intra prediction, and also generates the decoded video for presentation on a display device.

[0062] Some exemplary embodiments of the present disclosure will be described in detail below. Section headings are used herein for ease of understanding, but it should be understood that they do not limit the embodiments disclosed in a section to only that section. Furthermore, although certain embodiments are described with reference to versatile video coding or other specific video codecs, the disclosed techniques are applicable to other video coding techniques. Furthermore, although some embodiments describe video coding steps in detail, it will be understood that the corresponding decoding steps that undo the coding are performed by a decoder. Furthermore, the term video processing encompasses video coding or compression, video decoding or decompression, and video transcoding, which represents video pixels from one compressed format to another compressed format or at a different compressed bit rate. 1. Overview This disclosure relates to image / video coding techniques, and in particular to Versatile Video Coding (VVC) range extension, signaling of General Constraint Information (GCI) flags. The ideas can be applied individually or in various combinations to video bitstreams coded by video codecs such as the VVC standard. 2. Background 2.1. Video Coding Standards Video coding standards have evolved primarily through the development of well-known ITU-T and ISO / IEC standards. ITU-T created H.261 and H.263, ISO / IEC created MPEG-1 and MPEG-4 Visual, and the two organizations jointly created the H.262 / MPEG-2 Video, H.264 / MPEG-4 Advanced Video Coding (AVC), and H.265 / HEVC standards. Since H.262, video coding standards have been based on a hybrid video coding structure where temporal prediction plus transform coding is utilized. To explore future video coding technologies beyond HEVC, the Joint Video Exploration Team (JVET) was jointly established by VCEG and MPEG in 2015. Since then, many new methods have been adopted by JVET and incorporated into a reference software named the Joint Exploration Model (JEM). JVET was later renamed to Joint Video Experts Team (JVET) when the Versatile Video coding (VVC) project was officially launched. VVC is a new coding standard that aims for a 50% bitrate reduction compared to HEVC, and was finalized by JVET at its 19th meeting, which ended on July 1, 2020. The Versatile Video Coding (VVC) standard (ITU-T H.266 | ISO / IEC 23090-3) and the associated Versatile Supplemental Enhancement Information (VSEI) standard for coded video bitstreams (ITU-T H.274 | ISO / IEC 23002-7) are designed to be used in the widest range of applications, including both traditional applications such as television broadcasting, videoconferencing, or playback from storage media, and newer, more advanced applications such as adaptive bitrate streaming, video region extraction, composition and combining of content from multiple coded video bitstreams, multiview video, scalable layered coding, and viewport-adaptive 360° immersive media. The Essential Video Coding (EVC) standard (ISO / IEC 23094-1) is another video coding standard recently developed by MPEG. The latest revised draft of the VVC standard includes specifications for range extension and several other aspects. 2.2. Profiles, Layers, Levels (PTL) and Subprofiles in VVC VVC v1 defines six profiles, as listed in Table 1. Each of these profiles is defined to address a wide range of applications and has a logical "nesting" relationship with each other. In Table 1, the term "4:2:0" refers to video with chroma color planes that are half the width and half the height of the luma plane, which is the most common format used to encode camera-captured content in consumer applications. "4:4:4" refers to using chroma color planes that are the same width and height as the luma plane, commonly used for graphics, display monitors, and computer desktop rendering. "4:2:2" is a less common format with half the width and the same height as the luma, and is often used, for example, in studios for interlaced captured video. Monochrome video has only a single color plane, called the luma plane (which may not actually represent a luma signal, but may represent, for example, a depth map for 3D video applications or a transparency map that overlays the decoded video on a background). It should be noted that a decoder conforming to the Still Image Profile shall be able to decode the first picture of a typical Video Profile bitstream, since the first picture in the bitstream is usually an intra-coded picture. Such a decoder can also decode other IRAP pictures extracted as snapshots from the video bitstream. This subset relationship between the Video and Still Image Profiles provides the ability to share encoder and decoder modules for use in different applications (there is a trend towards convergence until most new video cameras can also be used for still photography, and vice versa). [Table 1] The PTL information is signaled using a syntax structure that can be included in a VPS (where the PTL structure applies to one or more OLSs) or an SPS (where the layer to which the PTL structure points), including the PTL to which the bitstream conforms and additional PTLs for temporal sublayer representations, each of which is a self-contained subset of the bitstream. In addition to the profiles defined in the VVC specification as shown in Table 1, VVC also allows an encoder to signal the conformance of a bitstream to a sub-profile. A sub-profile is an interoperability subset indicator, similar to a profile, that imposes further restrictions on an existing specified profile. Such sub-profiles are defined outside the VVC specification and are indicated using registered identifier codes as specified in Rec. ITU-T T.35 to avoid multiple meanings being defined for the same sub-profile code value. External organizations may define their own sub-profiles that are deemed sufficient to meet the needs of a particular application. The sub-profile indicator syntax element in the PTL structure allows for signaling within a bitstream that the bitstream conforms to such externally defined restrictions. 2.3. VVC General Constraint Information (GCI) In VVC, in addition to the profile, tier, and level (PTL) information, the PTL syntax structure may also optionally contain a General Constraint Information (GCI) syntax structure, which contains a list of constraint flags and non-flag syntax elements that indicate certain constraint properties of the bitstream. If present, a GCI syntax element value greater than 0 indicates that the bitstream is constrained in a particular manner, typically indicating that a particular coding tool is not used in the bitstream, while a value of 0 signals that the associated constraint may not be applied, allowing (but not requiring) the associated coding tool to be used in the bitstream (if its use is supported by the indicated profile). GCI includes several types of constraint syntax elements, including the following: - Flags for general bitstream restrictions, such as indicating that only intra-coding is used, that all layers are independently coded, or that the bitstream contains only one AU; - fields constraining the bit depth and chroma format of the coded picture, - a flag indicating that a particular NAL unit type is not allowed to be present in the bitstream, - flags that constrain how pictures are divided into slices, tiles, and subpictures in the bitstream; - flags limiting the size of the CTU and the size and type of the partitioning tree, - flags that constrain the use of certain intracoding tools, - flags that constrain the use of certain intercoding tools, - flags that constrain the transform, quantization, and residual coding tools, and - Flags that constrain aspects of the in-loop filter. The purpose of the GCI syntax structure is to allow easy discovery of configuration information regarding features required for decoding of a bitstream, and to permit interoperability points that impose restrictions beyond those specified in the PTL to be signaled at a finer granularity than previous video coding standards allowed. Similar to sub-profiles, the use of the GCI syntax structure allows for defining interoperability for decoder implementations that do not support all features of the VVC profile, but address the needs of a particular application. A decoder implementation may check the GCI syntax elements to see if a bitstream avoids the use of certain features, in order to determine how to configure the decoding process and to identify whether the bitstream is decodable by the decoder. A decoder implementation that supports all features of the VVC profile may ignore the GCI syntax element values, since such a decoder can decode any bitstream that conforms to the indicated PTL. Unlike sub-profile indicators, whose semantics are defined outside the VVC specification, the semantics of GCI syntax elements are defined within the VVC specification. Sub-profiles can also be used in combination with GCI, with the sub-profile imposing constraints on the values ​​of GCI syntax elements. Using GCI together with or instead of sub-profile indicators avoids the possibility that the meaning of the sub-profile indicators will not be recognized by the decoder (because the meaning of the sub-profile indicators does not need to be exposed). The syntax of the GCI syntax construct is as follows: [Table 2] TIFF2024538467000004.tif254166TIFF2024538467000005.tif254165In the syntax of the GCI syntax structure, the first syntax element is gci_present_flag which gates the presence of all GCI syntax elements as well as bits that are reserved for future GCI syntax elements. For simplicity, all syntax elements in the GCI syntax structure except gci_present_flag, gci_num_reserved_bits, gci_reserved_zero_bit[i], and gci_alignment_zero_bit are referred to as GCI syntax elements. The semantics of some GCI syntactic constructs are as follows: When gci_present_flag is equal to 1, it specifies that the GCI syntax element is present in the general_constraints_info() syntax structure. When gci_present_flag is equal to 0, it specifies that the GCI field is not present in the general_constraints_info() syntax structure. The semantics of the GCI syntax element specified in this clause apply when gci_present_flag is equal to 1. When gci_present_flag is equal to 0, the general_constraint_info() syntax structure does not impose any constraints. When gci_intra_only_constraint_flag is equal to 1, it specifies that sh_slice_type for all slices in OlsInScope is equal to 2. When gci_intra_only_constraint_flag is equal to 0, no such constraint is imposed. ... 2.4. General Constraint Information (GCI) Flags in VVC Range Extension During the development of the VVC range extension, six new GCI flags were added: 1) gci_all_rap_pictures_constraint_flag 2) gci_no_extended_precision_processing_constraint_flag 3) gci_no_ts_residual_coding_rice_constraint_flag 4) gci_no_rrc_rice_extension_constraint_flag 5) gci_no_persistent_rice_adaptation_constraint_flag 6) gci_no_reverse_last_sig_coeff_constraint_flag (outside 1) TIFF2024538467000006.tif19163 [Table 3] For simplicity, all syntax elements in the updated GCI syntax structure, except for gci_present_flag, gci_num_additional_bits, gci_reserved_zero_bit[i], and gci_alignment_zero_bit, are referred to as GCI syntax elements. Changes to the semantics of GCI syntax constructs are: ... (outside 2) TIFF2024538467000008.tif44163 gci_num_additional_bits specifies the number of additional GCI bits in the General Constraint Information syntax structure other than the gci_alignment_zero_bit syntax element (if present). The value of gci_num_additional_bits shall be equal to 0 or 1 in bitstreams conforming to this version of this document. Values ​​greater than 1 for gci_num_additional_bits are reserved for future use by ITU-T | ISO / IEC. Although this version of this document requires that the value of gci_num_additional_bits be 0 or 1, decoders conforming to this version of this document shall permit values ​​of gci_num_additional_bits greater than 1 to appear in the syntax and shall ignore the values ​​of all gci_reserved_zero_bit[i] syntax elements if gci_num_additional_bits is greater than 1. When gci_all_rap_pictures_constraint_flag is equal to 1, it specifies that all pictures in OlsInScope are GDR pictures or IRAP pictures with ph_recovery_poc_cnt equal to 0. When gci_all_rap_pictures_constraint_flag is equal to 0, no such constraint is imposed. When gci_no_extended_precision_processing_constraint_flag is equal to 1, it specifies that sps_extended_precision_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_extended_precision_processing_constraint_flag is equal to 0, no such constraint is imposed. If gci_no_ts_residual_coding_rice_constraint_flag is equal to 1, it specifies that sps_ts_residual_coding_rice_present_in_sh_flag for all pictures in OlsInScope is equal to 0. g If ci_no_ts_residual_coding_rice_constraint_flag is equal to 0, no such constraint is imposed. When gci_no_rrc_rice_extension_constraint_flag is equal to 1, it specifies that sps_rrc_rice_extension_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_rrc_rice_extension_constraint_flag is equal to 0, no such constraint is imposed. When gci_no_persistent_rice_adaptation_constraint_flag is equal to 1, it specifies that sps_persistent_rice_adaptation_enabled_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_persistent_rice_adaptation_constraint_flag is equal to 0, no such constraint is imposed. When gci_no_reverse_last_sig_coeff_constraint_flag is equal to 1, it specifies that sps_reverse_last_sig_coeff_enabled_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_reverse_last_sig_coeff_constraint_flag is equal to 0, no such constraint is imposed. ... 3. Problems If gci_present_flag is equal to 0, then no GCI syntax elements containing new range extension GCI flags are present. In that case, the general_constraint_info() syntax structure imposes no constraints. However, if gci_present_flag is equal to 1, then all GCI syntax elements specified in VVC Edition 1 are definitely present, but new range extension GCI flags may or may not be present depending on whether gci_num_additional_bits (which in VVC Edition 1 is gci_num_reserved_bits) is greater than 0. A problem arises when gci_present_flag is equal to 1 and gci_num_additional_bits is equal to 0, in which case no new range-extended GCI flags are present, but their values ​​are not inferred, so it is unclear whether the constraints specified by the flags equal to 1 apply. 4. Detailed solutions In order to solve the above problems, the methods summarized below are disclosed. The solutions should be considered as examples to illustrate the general concept and should not be interpreted narrowly. Moreover, these solutions can be applied individually or in combination in any manner. 1) In one example, if gci_present_flag is equal to 1 and gci_num_additional_bits is equal to 0, then the value of each of the six new VVC range extension GCI flags (listed below) is inferred to be equal to 0. a. gci_all_rap_pictures_constraint_flag b. gci_no_extended_precision_processing_constraint_flag c. gci_no_ts_residual_coding_rice_constraint_flag d. gci_no_rrc_rice_extension_constraint_flag e. gci_no_persistent_rice_adaptation_constraint_flag f. gci_no_reverse_last_sig_coeff_constraint_flag 2) Alternatively, in another example, the value of each of the six new VVC range extension GCI flags is inferred to be equal to 0 whenever not present. 3) Alternatively, in yet another example, the respective values ​​of all GCI syntax elements, including those specified in VVC Edition 1 and the six new VVC range extension GCI flags, are inferred to be equal to 0 whenever not present. 5. Embodiments (Outside 3) TIFF2024538467000009.tif201635.1. Embodiment 1 This embodiment corresponds to item 1 of section 4. The semantics of the GCI syntax constructs are as follows: All syntax elements in the GCI syntax structure except gci_present_flag, gci_num_additional_bits, gci_reserved_zero_bit[i], and gci_alignment_zero_bit are referred to as GCI syntax elements. (outside 4) TIFF2024538467000010.tif29163Specified in this clause gci_intra_only_constraint_flag from gci_no_virtual_boundaries_constraint_flag The semantics of GCI syntax elements apply when gci_present_flag is equal to 1. When gci_present_flag is equal to 0, the general_constraint_info() syntax constructs impose no constraints. When gci_intra_only_constraint_flag is equal to 1, it specifies that sh_slice_type for all slices in OlsInScope shall be equal to 2. When gci_intra_only_constraint_flag is equal to 0, no such constraint is imposed. ... If gci_sixteen_minus_max_bitdepth_constraint_idc is greater than 0, it specifies that the value of sps_bitdepth_minus8 plus 8 for all pictures in OlsInScope shall be in the range of 0 to 16-gci_sixteen_minus_max_bitdepth_constraint_idc. If gci_sixteen_minus_max_bitdepth_constraint_idc is equal to 0, Such No constraint is imposed. The value of gci_sixteen_minus_max_bitdepth_constraint_idc shall be in the range of 0 to 8. If gci_three_minus_max_chroma_format_constraint_idc is greater than 0, it specifies that sps_chroma_format_idc for all pictures in OlsInScope shall be in the range of 0 to 3-gci_three_minus_max_chroma_format_constraint_idc. If gci_three_minus_max_chroma_format_constraint_idc is equal to 0, Such No restrictions are imposed. ... gci_num_additional_bits specifies the number of additional GCI bits in the General Constraint Information syntax structure other than the gci_alignment_zero_bit syntax element (if present). The value of gci_num_additional_bits shall be equal to 0 or 1 in bitstreams conforming to this version of this document. Values ​​greater than 1 for gci_num_additional_bits are reserved for future use by ITU-T | ISO / IEC. Although this version of this document requires that the value of gci_num_additional_bits be 0 or 1, decoders conforming to this version of this document shall permit values ​​of gci_num_additional_bits greater than 1 to appear in the syntax and shall ignore the values ​​of all gci_reserved_zero_bit[i] syntax elements if gci_num_additional_bits is greater than 1. When gci_all_rap_pictures_constraint_flag is equal to 1, it specifies that all pictures in OlsInScope are GDR pictures or IRAP pictures with ph_recovery_poc_cnt equal to 0. When gci_all_rap_pictures_constraint_flag is equal to 0, no such constraint is imposed. If gci_present_flag is equal to 1 and gci_num_additional_bits is equal to 0, a value of gci_all_rap_pictures_constraint_flag is inferred to be equal to 0. When gci_no_extended_precision_processing_constraint_flag is equal to 1, it specifies that sps_extended_precision_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_extended_precision_processing_constraint_flag is equal to 0, no such constraint is imposed. If gci_present_flag is equal to 1 and gci_num_additional_bits is equal to 0, the value of gci_no_extended_precision_processing_constraint_flag is inferred to be equal to 0. When gci_no_ts_residual_coding_rice_constraint_flag is equal to 1, it specifies that sps_ts_residual_coding_rice_present_in_sh_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_ts_residual_coding_rice_constraint_flag is equal to 0, no such constraint is imposed. If gci_present_flag is equal to 1 and gci_num_additional_bits is equal to 0, the value of gci_no_ts_residual_coding_rice_constraint_flag is inferred to be equal to 0. When gci_no_rrc_rice_extension_constraint_flag is equal to 1, it specifies that sps_rrc_rice_extension_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_rrc_rice_extension_constraint_flag is equal to 0, no such constraint is imposed. If gci_present_flag is equal to 1 and gci_num_additional_bits is equal to 0, the value of gci_no_rrc_rice_extension_constraint_flag is inferred to be equal to 0. When gci_no_persistent_rice_adaptation_constraint_flag is equal to 1, it specifies that sps_persistent_rice_adaptation_enabled_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_persistent_rice_adaptation_constraint_flag is equal to 0, no such constraint is imposed. If gci_present_flag is equal to 1 and gci_num_additional_bits is equal to 0, the value of gci_no_persistent_rice_adaptation_constraint_flag is inferred to be equal to 0. When gci_no_reverse_last_sig_coeff_constraint_flag is equal to 1, it specifies that sps_reverse_last_sig_coeff_enabled_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_reverse_last_sig_coeff_constraint_flag is equal to 0, no such constraint is imposed. If gci_present_flag is equal to 1 and gci_num_additional_bits is equal to 0, the value of gci_no_reverse_last_sig_coeff_constraint_flag is inferred to be equal to 0. ... 5.2. Embodiment 2 This embodiment corresponds to item 2 of section 4. The semantics of the GCI syntax constructs are as follows: All syntax elements in the GCI syntax structure except gci_present_flag, gci_num_additional_bits, gci_reserved_zero_bit[i], and gci_alignment_zero_bit are referred to as GCI syntax elements. (outside 5) TIFF2024538467000011.tif29163Specified in this clause From gci_intra_only_constraint_flag to gci_no_virtual_boundaries_constraint_flag The semantics of GCI syntax elements apply when gci_present_flag is equal to 1. When gci_present_flag is equal to 0, the general_constraint_info() syntax constructs impose no constraints. When gci_intra_only_constraint_flag is equal to 1, it specifies that sh_slice_type for all slices in OlsInScope shall be equal to 2. When gci_intra_only_constraint_flag is equal to 0, no such constraint is imposed. ... If gci_sixteen_minus_max_bitdepth_constraint_idc is greater than 0, it specifies that the value of sps_bitdepth_minus8 plus 8 for all pictures in OlsInScope shall be in the range of 0 to 16-gci_sixteen_minus_max_bitdepth_constraint_idc. If gci_sixteen_minus_max_bitdepth_constraint_idc is equal to 0, Such No constraint is imposed. The value of gci_sixteen_minus_max_bitdepth_constraint_idc shall be in the range of 0 to 8. If gci_three_minus_max_chroma_format_constraint_idc is greater than 0, it specifies that sps_chroma_format_idc for all pictures in OlsInScope shall be in the range of 0 to 3-gci_three_minus_max_chroma_format_constraint_idc. If gci_three_minus_max_chroma_format_constraint_idc is equal to 0, Such No restrictions are imposed. ... gci_num_additional_bits specifies the number of additional GCI bits in the General Constraint Information syntax structure other than the gci_alignment_zero_bit syntax element (if present). The value of gci_num_additional_bits shall be equal to 0 or 1 in bitstreams conforming to this version of this document. Values ​​greater than 1 for gci_num_additional_bits are reserved for future use by ITU-T | ISO / IEC. Although this version of this document requires that the value of gci_num_additional_bits be 0 or 1, decoders conforming to this version of this document shall permit values ​​of gci_num_additional_bits greater than 1 to appear in the syntax and shall ignore the values ​​of all gci_reserved_zero_bit[i] syntax elements if gci_num_additional_bits is greater than 1. When gci_all_rap_pictures_constraint_flag is equal to 1, it specifies that all pictures in OlsInScope are GDR pictures or IRAP pictures with ph_recovery_poc_cnt equal to 0. When gci_all_rap_pictures_constraint_flag is equal to 0, no such constraint is imposed. If not present, the value of gci_all_rap_pictures_constraint_flag is inferred to be equal to 0. When gci_no_extended_precision_processing_constraint_flag is equal to 1, it specifies that sps_extended_precision_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_extended_precision_processing_constraint_flag is equal to 0, no such constraint is imposed. If not present, the value of gci_no_extended_precision_processing_constraint_flag is inferred to be equal to 0. When gci_no_ts_residual_coding_rice_constraint_flag is equal to 1, it specifies that sps_ts_residual_coding_rice_present_in_sh_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_ts_residual_coding_rice_constraint_flag is equal to 0, no such constraint is imposed. If not present, the value of gci_no_ts_residual_coding_rice_constraint_flag is inferred to be equal to 0. When gci_no_rrc_rice_extension_constraint_flag is equal to 1, it specifies that sps_rrc_rice_extension_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_rrc_rice_extension_constraint_flag is equal to 0, no such constraint is imposed. If not present, the value of gci_no_rrc_rice_extension_constraint_flag is inferred to be equal to 0. When gci_no_persistent_rice_adaptation_constraint_flag is equal to 1, it specifies that sps_persistent_rice_adaptation_enabled_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_persistent_rice_adaptation_constraint_flag is equal to 0, no such constraint is imposed. If not present, the value of gci_no_persistent_rice_adaptation_constraint_flag is inferred to be equal to 0. When gci_no_reverse_last_sig_coeff_constraint_flag is equal to 1, it specifies that sps_reverse_last_sig_coeff_enabled_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_reverse_last_sig_coeff_constraint_flag is equal to 0, no such constraint is imposed. If not present, the value of gci_no_reverse_last_sig_coeff_constraint_flag is inferred to be equal to 0. ... 5.3. Third embodiment This embodiment corresponds to item 3 of section 4. The semantics of the GCI syntax constructs are as follows: All syntax elements in the GCI syntax structure except gci_present_flag, gci_num_additional_bits, gci_reserved_zero_bit[i], and gci_alignment_zero_bit are referred to as GCI syntax elements. If any GCI syntax element is not present, the value of that GCI syntax element is inferred to be equal to 0. (outside 6) TIFF2024538467000012.tif30163The semantics of the GCI syntax elements specified in this clause apply when gci_present_flag is equal to 1. When gci_present_flag is equal to 0, the general_constraint_info() syntax construct imposes no constraints. When gci_intra_only_constraint_flag is equal to 1, it specifies that sh_slice_type for all slices in OlsInScope shall be equal to 2. When gci_intra_only_constraint_flag is equal to 0, no such constraint is imposed. ... If gci_sixteen_minus_max_bitdepth_constraint_idc is greater than 0, it specifies that the value of sps_bitdepth_minus8 plus 8 for all pictures in OlsInScope shall be in the range of 0 to 16-gci_sixteen_minus_max_bitdepth_constraint_idc. If gci_sixteen_minus_max_bitdepth_constraint_idc is equal to 0, Such No constraint is imposed. The value of gci_sixteen_minus_max_bitdepth_constraint_idc shall be in the range of 0 to 8. Specifies that sps_chroma_format_idc for all pictures in OlsInScope must be in the range of 0 to 3-gci_three_minus_max_chroma_format_constraint_idc if gci_three_minus_max_chroma_format_constraint_idc is greater than 0. If gci_three_minus_max_chroma_format_constraint_idc is equal to 0, Such No restrictions are imposed. ... gci_num_additional_bits specifies the number of additional GCI bits in the General Constraint Information syntax structure other than the gci_alignment_zero_bit syntax element (if present). The value of gci_num_additional_bits shall be equal to 0 or 1 in bitstreams conforming to this version of this document. Values ​​greater than 1 for gci_num_additional_bits are reserved for future use by ITU-T | ISO / IEC. Although this version of this document requires that the value of gci_num_additional_bits be 0 or 1, decoders conforming to this version of this document shall permit values ​​of gci_num_additional_bits greater than 1 to appear in the syntax and shall ignore the values ​​of all gci_reserved_zero_bit[i] syntax elements if gci_num_additional_bits is greater than 1. When gci_all_rap_pictures_constraint_flag is equal to 1, it specifies that all pictures in OlsInScope are GDR pictures or IRAP pictures with ph_recovery_poc_cnt equal to 0. When gci_all_rap_pictures_constraint_flag is equal to 0, no such constraint is imposed. When gci_no_extended_precision_processing_constraint_flag is equal to 1, it specifies that sps_extended_precision_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_extended_precision_processing_constraint_flag is equal to 0, no such constraint is imposed. When gci_no_ts_residual_coding_rice_constraint_flag is equal to 1, it specifies that sps_ts_residual_coding_rice_present_in_sh_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_ts_residual_coding_rice_constraint_flag is equal to 0, no such constraint is imposed. When gci_no_rrc_rice_extension_constraint_flag is equal to 1, it specifies that sps_rrc_rice_extension_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_rrc_rice_extension_constraint_flag is equal to 0, no such constraint is imposed. When gci_no_persistent_rice_adaptation_constraint_flag is equal to 1, it specifies that sps_persistent_rice_adaptation_enabled_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_persistent_rice_adaptation_constraint_flag is equal to 0, no such constraint is imposed. When gci_no_reverse_last_sig_coeff_constraint_flag is equal to 1, it specifies that sps_reverse_last_sig_coeff_enabled_flag for all pictures in OlsInScope shall be equal to 0. When gci_no_reverse_last_sig_coeff_constraint_flag is equal to 0, no such constraint is imposed. ...

[0063] An embodiment of the present disclosure relates to signaling of a VVC range extension general constraint information flag.

[0064] FIG. 4 illustrates a flowchart of a method 400 for video processing according to some embodiments of the present disclosure. As shown in FIG. 4, at 402, conversion between a current video block of a video and a bitstream of the video is performed based on general constraint information (GCI) of the video. As used herein, the term "block" may represent a video processing unit including a coding tree block (CTB), a coding tree unit (CTU), a coding block (CB), a coding unit (CU), a prediction unit (PU), a transform unit (TU), a prediction block (PB), a transform block (TB), a number of samples / pixels, etc. A block may be rectangular or non-rectangular. In some embodiments, the conversion may include encoding the current video block into a bitstream. Additionally or alternatively, the conversion may include decoding the current video block from the bitstream.

[0065] The GCI indicates certain constraint characteristics of the bitstream. The GCI includes one or more syntax elements from the following syntax elements: (1) a first syntax element indicating whether all pictures in one or more output layer sets (OLS) are recovery point pictures or intra random access point (IRAP) pictures, (2) a second syntax element indicating whether extended dynamic range is used for the scaling and transformation process and binarization of the syntax elements abs_remaining and dec_abs_level for all pictures in one or more OLSs, (3) whether the slice parameters used for the syntax structure residual_ts_coding in the current slice are indicated in the syntax structure slice_header pointing to a sequence parameter set (SPS) for all pictures in one or more OLSs. (4) a fourth syntax element indicating, for all pictures in one or more OLSs, whether an alternative Rice parameter derivation is used for the binarization of syntax elements abs_remaining and dec_abs_level; (5) a fifth syntax element indicating, for all pictures in one or more OLSs, whether a Rice parameter derivation for the binarization of syntax elements abs_remaining and dec_abs_level is initialized at the beginning of each TU using statistics accumulated from a previous transform unit (TU); or (6) a sixth syntax element indicating, for all pictures in one or more OLSs, whether a syntax element sh_reverse_last_sig_coeff_flag is present in a syntax structure slice_header pointing to the SPS. Each of the one or more syntax elements mentioned above is not present in the bitstream and has a value equal to a first predetermined value. In one example, the first predetermined value may be equal to 0. It should be understood that the first predetermined value may be any other suitable value, such as 1. The scope of the present disclosure is not limited in this respect.

[0066] In some embodiments, the first syntax element may be the syntax element gci_all_rap_pictures_constraint_flag, the second syntax element may be the syntax element gci_no_extended_precision_processing_constraint_flag, the third syntax element may be the syntax element gci_no_ts_residual_coding_rice_constraint_flag, the fourth syntax element may be the syntax element gci_no_rrc_rice_extension_constraint_flag, the fifth syntax element may be the syntax element gci_no_persistent_rice_adaptation_constraint_flag, and the sixth syntax element may be the syntax element gci_no_reverse_last_sig_coeff_constraint_flag. As an example, if the syntax element gci_all_rap_pictures_constraint_flag is not present in the bitstream, its value may be inferred to be 0.

[0067] Based on the above, the value of each of the six GCI syntax elements is inferred to be equal to a predetermined value (e.g., 0) if it is not present in the bitstream. Compared with the conventional solution in which the values ​​of these GCI syntax elements are not inferred, the proposed method has the advantage that the values ​​of these GCI syntax elements can be obtained even if they are not present in the bitstream, thereby ensuring a uniform process of video processing and improving coding efficiency.

[0068] In some embodiments, the GCI may further include a seventh syntax element and an eighth syntax element. The seventh syntax element may indicate whether a GCI syntax element is present in the syntax structure for the GCI. The seventh syntax element may have a value equal to a second predetermined value. The eighth syntax element may indicate a number of additional GCI bits other than the syntax element gci_alignment_zero_bit in the syntax structure. The eighth syntax element may have a value equal to a third predetermined value. In one example, the seventh syntax element may be a syntax element gci_present_flag and the eighth syntax element may be a syntax element gci_num_additional_bits. Further, the second predetermined value may be 1 and the third predetermined value may be 0. It should be understood that the second and third predetermined values ​​may be other suitable values. The scope of the present disclosure is not limited in this respect.

[0069] Alternatively, or in addition, the GCI may further include a ninth syntax element different from the first syntax element, the second syntax element, the third syntax element, the fourth syntax element, the fifth syntax element, and the sixth syntax element. The ninth syntax element may be absent from the bitstream and have a value equal to a first predetermined value. For example, the ninth syntax element may be one of the GCI syntax elements specified in VVC Edition 1, such as syntax element gci_intra_only_constraint_flag, syntax element gci_no_virtual_boundaries_constraint_flag, etc. If the syntax element gci_intra_only_constraint_flag is absent from the bitstream, its value may be inferred to be 0. It should be understood that the above discussion and / or examples are provided for illustrative purposes only. The scope of the present disclosure is not limited in this respect.

[0070] According to an embodiment of the present invention, a non-transitory computer-readable recording medium is proposed. A bitstream of a video is stored in the non-transitory computer-readable recording medium. The bitstream may be generated by a method executed by a video processing device. According to the method, conversion between a current video block of a video and a bitstream of a video is performed based on a General Constraint Information (GCI) of the video. The GCI includes a first syntax element indicating whether all pictures in one or more Output Layer Sets (OLS) are recovery point pictures or Intra Random Access Point (IRAP) pictures, a second syntax element indicating whether extended dynamic range is used for the scaling and transformation process and binarization of the syntax elements abs_remaining and dec_abs_level for all pictures in one or more OLSs, a third syntax element indicating whether the Rice parameters used for the syntax structure residual_ts_coding in the current slice are indicated in a syntax structure slice_header pointing to a Sequence Parameter Set (SPS) for all pictures in one or more OLSs, a fourth syntax element indicating whether the Rice parameters used for the syntax structure residual_ts_coding in the current slice are indicated in a syntax structure slice_header pointing to a Sequence Parameter Set (SPS), a fifth syntax element indicating whether the Rice parameters used for the syntax structure residual_ts_coding in the current slice are indicated in a syntax structure slice_header pointing to a Sequence Parameter Set (SPS), a sixth ... S, a fourth syntax element indicating whether an alternative Rice parameter derivation is used for the binarization of syntax elements abs_remaining and dec_abs_level for all pictures in one or more OLSs, a fifth syntax element indicating whether a Rice parameter derivation for the binarization of syntax elements abs_remaining and dec_abs_level is initialized at the beginning of each TU using statistics accumulated from previous transform units (TUs) for all pictures in one or more OLSs, or a sixth syntax element indicating whether a syntax element sh_reverse_last_sig_coeff_flag is present in a syntax structure slice_header pointing to the SPS for all pictures in one or more OLSs, each of which is not present in the bitstream and has a value equal to a first predetermined value.

[0071] According to an embodiment of the present invention, a method for storing a bitstream of a video is proposed, in which a conversion between a current video block of a video and a bitstream of the video is performed based on a General Constraint Information (GCI) of the video, and the bitstream is stored in a non-transitory computer-readable recording medium. The GCI includes a first syntax element indicating whether all pictures in one or more Output Layer Sets (OLS) are recovery point pictures or Intra Random Access Point (IRAP) pictures, a second syntax element indicating whether extended dynamic range is used for the scaling and transformation process and binarization of the syntax elements abs_remaining and dec_abs_level for all pictures in one or more OLSs, a third syntax element indicating whether the slice parameters used for the syntax structure residual_ts_coding in the current slice are indicated in a syntax structure slice_header pointing to a Sequence Parameter Set (SPS) for all pictures in one or more OLSs, a fourth syntax element indicating whether the slice parameters used for the syntax structure residual_ts_coding in the current slice are indicated in a syntax structure slice_header pointing to a Sequence Parameter Set (SPS), a fifth syntax element indicating whether the slice parameters used for the syntax structure residual_ts_coding in the current slice are indicated in a syntax structure slice_header pointing to a Sequence Parameter Set (SPS), and a fifth syntax element indicating whether the slice parameters used for the syntax structure residual_ts_coding in the current slice are indicated in a syntax structure slice_header pointing to a Sequence Parameter Set (SPS). S, a fourth syntax element indicating whether an alternative Rice parameter derivation is used for the binarization of syntax elements abs_remaining and dec_abs_level for all pictures in one or more OLSs, a fifth syntax element indicating whether a Rice parameter derivation for the binarization of syntax elements abs_remaining and dec_abs_level is initialized at the beginning of each TU using statistics accumulated from previous transform units (TUs) for all pictures in one or more OLSs, or a sixth syntax element indicating whether a syntax element sh_reverse_last_sig_coeff_flag is present in a syntax structure slice_header pointing to the SPS for all pictures in one or more OLSs, each of which is not present in the bitstream and has a value equal to a first predetermined value.

[0072] Implementations of the present disclosure can be described in light of the following clauses, the features of which can be combined in any reasonable manner.

[0073] Clause 1. A video processing method, comprising: performing a conversion between a current video block of the video and a bitstream of the video based on a general constraint information (GCI) of the video, the GCI comprising: a first syntax element indicating whether all pictures in one or more output layer sets (OLS) are recovery point pictures or intra random access point (IRAP) pictures; a second syntax element indicating whether extended dynamic range is used for the scaling and transformation process and binarization of syntax elements abs_remaining and dec_abs_level for all pictures in one or more OLSs; a third syntax element indicating whether slice parameters used for a syntax structure residual_ts_coding in a current slice are indicated in a syntax structure slice_header pointing to a sequence parameter set (SPS) for all pictures in one or more OLSs; a fourth syntax element indicating, for all pictures in one or more OLSs, whether an alternative Rice parameter derivation is used for the binarization of syntax elements abs_remaining and dec_abs_level; a fifth syntax element indicating, for all pictures in one or more OLSs, whether a Rice parameter derivation for the binarization of syntax elements abs_remaining and dec_abs_level is initialized at the beginning of each TU using statistics accumulated from a previous transform unit (TU); or a sixth syntax element indicating, for all pictures in one or more OLSs, whether a syntax element sh_reverse_last_sig_coeff_flag is present in a syntax structure slice_header pointing to the SPS, wherein each of the one or more syntax elements is not present in the bitstream and has a value equal to a first predetermined value.

[0074] Clause 2. The method of clause 1, wherein the first predetermined value is zero.

[0075] Clause 3. A method according to any one of clauses 1 to 2, wherein the first syntax element is the syntax element gci_all_rap_pictures_constraint_flag, the second syntax element is the syntax element gci_no_extended_precision_processing_constraint_flag, the third syntax element is the syntax element gci_no_ts_residual_coding_rice_constraint_flag, the fourth syntax element is the syntax element gci_no_rrc_rice_extension_constraint_flag, the fifth syntax element is the syntax element gci_no_persistent_rice_adaptation_constraint_flag, and the sixth syntax element is the syntax element gci_no_reverse_last_sig_coeff_constraint_flag.

[0076] Clause 4. A method according to any one of clauses 1 to 3, wherein the GCI further includes a seventh syntax element and an eighth syntax element, the seventh syntax element indicating whether a GCI syntax element is present in a syntax structure for the GCI, the eighth syntax element indicating the number of additional GCI bits other than the syntax element gci_alignment_zero_bit in the syntax structure, the seventh syntax element having a value equal to a second predetermined value, and the eighth syntax element having a value equal to a third predetermined value.

[0077] Clause 5. The method of clause 4, wherein the seventh syntax element is the syntax element gci_present_flag, the eighth syntax element is the syntax element gci_num_additional_bits, the second predetermined value is 1, and the third predetermined value is 0.

[0078] Clause 6. The method of any one of clauses 1 to 3, wherein the GCI further includes a ninth syntax element different from the first syntax element, the second syntax element, the third syntax element, the fourth syntax element, the fifth syntax element and the sixth syntax element, the ninth syntax element being absent from the bitstream and having a value equal to the first predetermined value.

[0079] Clause 7. The method of any one of clauses 1 to 6, wherein the converting comprises encoding the current video block into the bitstream.

[0080] Clause 8. The method of any one of clauses 1 to 6, wherein the converting comprises decoding the current video block from the bitstream.

[0081] Clause 9. An apparatus for processing video data comprising a processor and a non-transitory memory comprising instructions which, when executed by the processor, cause the processor to perform a method according to any one of clauses 1 to 8.

[0082] Clause 10. A non-transitory computer-readable storage medium storing instructions that cause a processor to perform the method of any one of clauses 1 to 8.

[0083] Clause 11. A non-transitory computer-readable recording medium storing a bitstream of a video generated by a method executed by a video processing device, the method comprising: performing a conversion between a current video block of the video and the bitstream of the video based on General Constraint Information (GCI) for the video, the GCI comprising: a first syntax element indicating whether all pictures in one or more Output Layer Sets (OLSs) are recovery point pictures or Intra Random Access Point (IRAP) pictures; a second syntax element indicating whether extended dynamic range is used for the scaling and transformation process and the binarization of syntax elements abs_remaining and dec_abs_level for all pictures in one or more OLSs; a syntax structure slice_seq_seq_ratio indicating whether a slice parameter used in the current slice is used for the syntax structure residual_ts_coding for all pictures in one or more OLSs; a third syntax element indicating whether an alternative Rice parameter derivation is indicated in a slice_header pointing to the SPS, a fourth syntax element indicating whether, for all pictures in one or more OLSs, an alternative Rice parameter derivation is used for the binarization of syntax elements abs_remaining and dec_abs_level, a fifth syntax element indicating whether, for all pictures in one or more OLSs, a Rice parameter derivation for the binarization of syntax elements abs_remaining and dec_abs_level is initialized at the beginning of each TU using accumulated statistics from a previous transform unit (TU), or a sixth syntax element indicating whether, for all pictures in one or more OLSs, a syntax element sh_reverse_last_sig_coeff_flag is present in a syntax structure slice_header pointing to the SPS, wherein each of the one or more syntax elements is not present in the bitstream and has a value equal to a first predetermined value.

[0084] Clause 12. A method for storing a bitstream of a video, comprising the steps of: performing a conversion between a current video block of the video and the bitstream of the video based on a general constraint information (GCI) for the video, the GCI comprising: a first syntax element indicating whether all pictures in one or more output layer sets (OLS) are recovery point pictures or intra random access point (IRAP) pictures; a second syntax element indicating whether extended dynamic range is used for the scaling and transformation process and the binarization of the syntax elements abs_remaining and dec_abs_level for all pictures in one or more OLSs; a third syntax element indicating whether the slice parameters used for the syntax structure residual_ts_coding in the current slice are indicated in a syntax structure slice_header pointing to a sequence parameter set (SPS) for all pictures in one or more OLSs; a fourth syntax element indicating whether an alternative Rice parameter derivation is used for the binarization of syntax elements abs_remaining and dec_abs_level for all pictures in S, a fifth syntax element indicating whether a Rice parameter derivation for the binarization of syntax elements abs_remaining and dec_abs_level is initialized at the beginning of each TU using statistics accumulated from previous transform units (TUs) for all pictures in one or more OLSs, or a sixth syntax element indicating whether a syntax element sh_reverse_last_sig_coeff_flag is present in a syntax structure slice_header pointing to the SPS, and storing the bitstream in a non-transitory computer-readable recording medium, wherein each of the one or more syntax elements is not present in the bitstream and has a value equal to a first predetermined value.

[0085] Exemplary Devices

[0086] 5 illustrates a block diagram of a computing device 500 capable of implementing various embodiments of the present disclosure. The computing device 500 may be embodied as or included in the source device 110 (or the video encoder 114 or 200) or the destination device 120 (or the video decoder 124 or 300).

[0087] It will be appreciated that the computing device 500 illustrated in FIG. 5 is for illustrative purposes only and is not intended to suggest any limitation on the functionality and scope of the embodiments of the present disclosure.

[0088] 5, the computing device 500 includes a general purpose computing device 500. The computing device 500 may include at least one or more processors or processing units 510, a memory 520, a storage unit 530, one or more communication units 540, one or more input devices 550, and one or more output devices 560.

[0089] In some embodiments, the computing device 500 may be embodied as any user terminal or server terminal having computing capabilities. The server terminal may be a server provided by a service provider, a large-scale computing device, etc. The user terminal may be any type of mobile, fixed, or portable terminal, including, for example, a mobile phone, a station, a unit, a device, a multimedia computer, a multimedia tablet, an Internet node, a communicator, a desktop computer, a laptop computer, a notebook computer, a netbook computer, a tablet computer, a personal communication system (PCS) device, a personal navigation device, a personal digital assistant (PDA), an audio / video player, a digital camera / camcorder, a positioning device, a television receiver, a radio broadcast receiver, an electronic book device, a gaming device, or any combination thereof (including accessories and peripherals of these devices, or any combination thereof). It is contemplated that the computing device 500 may support any type of interface to a user, such as "wearable" circuitry.

[0090] The processing unit 510 may be a physical or virtual processor and may implement various processes based on programs stored in the memory 520. In a multiprocessor system, multiple processing units execute computer-executable instructions in parallel to increase the parallel processing capabilities of the computing device 500. The processing unit 510 may also be referred to as a central processing unit (CPU), a microprocessor, a controller, or a microcontroller.

[0091] Computing device 500 typically includes a variety of computer storage media. Such media may be any media accessible by computing device 500, including but not limited to volatile and non-volatile media, or removable and non-removable media. Memory 520 may be volatile memory (e.g., registers, cache, random access memory (RAM)), non-volatile memory (e.g., read only memory (ROM), electrically erasable programmable read only memory (EEPROM), flash memory), or any combination thereof. Storage unit 530 may be any removable or non-removable media, including machine-readable media such as memory, flash memory drives, magnetic disks, or other media that can be used to store information and / or data and that can be accessed by computing device 500.

[0092] The computing device 500 may further include additional removable / non-removable, volatile / non-volatile memory media. Although not shown in FIG. 5, a magnetic disk drive that reads from and writes to a removable non-volatile magnetic disk and an optical disk drive that reads from and writes to a removable non-volatile optical disk may be provided. In such a case, each drive may be connected to a bus (not shown) via one or more data media interfaces.

[0093] The communication unit 540 communicates with further computing devices via a communication medium. Furthermore, the functionality of the components in the computing device 500 may be embodied by a single computing cluster or multiple computing machines that can communicate via a communication connection. Thus, the computing device 500 can operate in a networked environment using logical connections with one or more other servers, networked personal computers (PCs), or further general network nodes.

[0094] The input device 550 may be one or more of a variety of input devices such as a mouse, a keyboard, a tracking ball, a voice input device, etc. The output device 560 may be one or more of a variety of output devices such as a display, a loudspeaker, a printer, etc. The communication unit 540 allows the computing device 500 to further communicate with one or more external devices (not shown), such as a storage device and a display device, one or more devices allowing a user to interact with the computing device 500, or any device (such as a network card, a modem, etc.) allowing the computing device 500 to communicate with one or more other computing devices, as needed. Such communication may be performed via an input / output (I / O) interface (not shown).

[0095] In some embodiments, instead of being integrated into a single device, some or all of the components of the computing device 500 may be located in a cloud computing architecture. In a cloud computing architecture, the components may be provided remotely and work together to perform the functions described in this disclosure. In some embodiments, cloud computing provides computing, software, data access, and storage services without the end user needing to be aware of the physical location or configuration of the systems or hardware providing these services. In various embodiments, cloud computing provides services over a wide area network (such as the Internet) using appropriate protocols. For example, a cloud computing provider provides applications over a wide area network that can be accessed through a web browser or other computing components. The software or components of the cloud computing architecture and corresponding data may be stored on a server located in a remote location. Computing resources in a cloud computing environment may be consolidated or distributed at remote data center locations. A cloud computing infrastructure may act as a single access point for users but provide services through a shared data center. Thus, a cloud computing architecture may be used to provide the components and functions described herein from a service provider located in a remote location. Alternatively, they may be provided from a traditional server or installed directly or otherwise on a client device.

[0096] The computing device 500 may be used to implement video encoding / decoding in embodiments of the present disclosure. The memory 520 may include one or more video encoding modules 525 having one or more program instructions. These modules are accessible and executable by the processing unit 510 to perform the functions of various embodiments described herein.

[0097] In an example embodiment performing video encoding, input device 550 may receive video data to be encoded as input 570. The video data may be processed, for example, by video coding module 525 to generate an encoded bitstream. The encoded bitstream may be provided as output 580 via output device 560.

[0098] In an example embodiment performing video decoding, input device 550 may receive an encoded bitstream as input 570. The encoded bitstream may be processed, for example, by video coding module 525 to generate decoded video data. The decoded video data may be provided as output 580 via output device 560.

[0099] Although the present disclosure has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present application as defined by the appended claims. Such variations are intended to be within the scope of the present application. Accordingly, the foregoing description of the embodiments of the present application is not intended to be limiting.

Claims

1. 1. A video processing method comprising the steps of: performing a conversion between a current video block of the video and a bitstream of the video based on general constraint information (GCI) for the video; The GCI is A first syntax element indicating whether all pictures in one or more output layer sets (OLS) are recovery point pictures or intra random access point (IRAP) pictures; A second syntax element indicating whether extended dynamic range is used for the scaling and transformation process and the binarization of the syntax elements abs_remaining and dec_abs_level for all pictures in the one or more OLSs; a third syntax element indicating whether the Rice parameters used for the syntax structure residual_ts_coding in the current slice for all pictures in one or more OLSs are indicated in a syntax structure slice_header pointing to a sequence parameter set (SPS); a fourth syntax element indicating whether an alternative Rice parameter derivation is used for the binarization of the syntax elements abs_remaining and dec_abs_level for all pictures in one or more OLSs; a fifth syntax element indicating whether the Rice parameter derivation for the binarization of the syntax elements abs_remaining and dec_abs_level is initialized at the beginning of each transform unit (TU) using accumulated statistics from previous TUs for all pictures in one or more OLSs; or for all pictures in the one or more OLSs, including one or more syntax elements from a sixth syntax element indicating whether a syntax element sh_reverse_last_sig_coeff_flag is present in a syntax structure slice_header pointing to said SPS; 13. The method of claim 12, wherein each of the one or more syntax elements is absent from the bitstream and has a value equal to a first predetermined value.

2. The method of claim 1 , wherein the first predetermined value is zero.

3. The first syntax element is a syntax element gci_all_rap_pictures_constraint_flag, The second syntax element is a syntax element gci_no_extended_precision_processing_constraint_flag, The third syntax element is a syntax element gci_no_ts_residual_coding_rice_constraint_flag, The fourth syntax element is a syntax element gci_no_rrc_rice_extension_constraint_flag, The fifth syntax element is a syntax element gci_no_persistent_rice_adaptation_constraint_flag, The method according to claim 1 , wherein the sixth syntax element is a syntax element gci_no_reverse_last_sig_coeff_constraint_flag.

4. 4. The method of claim 1, wherein the GCI further includes a seventh syntax element and an eighth syntax element, the seventh syntax element indicating whether a GCI syntax element is present in a syntax structure for the GCI, the eighth syntax element indicating a number of additional GCI bits other than the syntax element gci_alignment_zero_bit in the syntax structure, the seventh syntax element having a value equal to a second predetermined value, and the eighth syntax element having a value equal to a third predetermined value.

5. 5. The method of claim 4, wherein the seventh syntax element is a syntax element gci_present_flag, the eighth syntax element is a syntax element gci_num_additional_bits, the second predetermined value is 1, and the third predetermined value is 0.

6. 4. The method of claim 1, wherein the GCI further comprises a ninth syntax element different from the first syntax element, the second syntax element, the third syntax element, the fourth syntax element, the fifth syntax element and the sixth syntax element, the ninth syntax element being absent from the bitstream and having a value equal to the first predetermined value.

7. The method of claim 1 , wherein the converting comprises encoding the current video block into the bitstream.

8. The method of claim 1 , wherein the conversion comprises decoding the current video block from the bitstream.

9. 1. An apparatus for processing video data comprising a processor and a non-transitory memory with instructions, comprising: An apparatus, the instructions, when executed by the processor, causing the processor to perform the method of any one of claims 1 to 8.

10. A non-transitory computer readable storage medium storing instructions that cause a processor to perform the method of any one of claims 1 to 8.

11. 1. A non-transitory computer-readable recording medium for storing a bitstream of video generated by a method performed by a video processing device, comprising: The method includes performing a conversion between a current video block of the video and a bitstream of the video based on general constraint information (GCI) for the video; The GCI is A first syntax element indicating whether all pictures in one or more output layer sets (OLS) are recovery point pictures or intra random access point (IRAP) pictures; A second syntax element indicating whether extended dynamic range is used for the scaling and transformation process and the binarization of the syntax elements abs_remaining and dec_abs_level for all pictures in the one or more OLSs; a third syntax element indicating whether the Rice parameters used for the syntax structure residual_ts_coding in the current slice for all pictures in one or more OLSs are indicated in a syntax structure slice_header pointing to a sequence parameter set (SPS); a fourth syntax element indicating whether an alternative Rice parameter derivation is used for the binarization of the syntax elements abs_remaining and dec_abs_level for all pictures in one or more OLSs; a fifth syntax element indicating whether the Rice parameter derivation for the binarization of the syntax elements abs_remaining and dec_abs_level is initialized at the beginning of each transform unit (TU) using accumulated statistics from previous TUs for all pictures in one or more OLSs; or For all pictures in the one or more OLSs, one or more syntax elements from a sixth syntax element indicating whether a syntax element sh_reverse_last_sig_coeff_flag is present in a syntax structure slice_header pointing to the SPS; 5. The non-transitory computer-readable storage medium of claim 1, wherein each of the one or more syntax elements is absent from the bitstream and has a value equal to a first predetermined value.

12. 1. A method for storing a video bitstream, comprising: performing a conversion between a current video block of the video and a bitstream of the video based on general constraint information (GCI) for the video, The GCI is a first syntax element indicating whether all pictures in one or more output layer sets (OLS) are recovery point pictures or intra random access point (IRAP) pictures; A second syntax element indicating whether extended dynamic range is used for the scaling and transformation process and the binarization of the syntax elements abs_remaining and dec_abs_level for all pictures in the one or more OLSs; a third syntax element indicating whether the Rice parameters used for the syntax structure residual_ts_coding in the current slice for all pictures in one or more OLSs are indicated in a syntax structure slice_header pointing to a sequence parameter set (SPS); a fourth syntax element indicating whether an alternative Rice parameter derivation is used for the binarization of the syntax elements abs_remaining and dec_abs_level for all pictures in one or more OLSs; a fifth syntax element indicating whether the Rice parameter derivation for the binarization of the syntax elements abs_remaining and dec_abs_level is initialized at the beginning of each transform unit (TU) using accumulated statistics from previous TUs for all pictures in one or more OLSs; or for all pictures in one or more OLSs, including one or more syntax elements from a sixth syntax element indicating whether a syntax element sh_reverse_last_sig_coeff_flag is present in a syntax structure slice_header pointing to said SPS; storing the bitstream on a non-transitory computer-readable recording medium; 13. The method of claim 12, wherein each of the one or more syntax elements is absent from the bitstream and has a value equal to a first predetermined value.

Images