Abstract: The present disclosure relates to methods and apparatuses for decoding data for (still or video processing into a bitstream). Two or more sets of segmentation information elements are obtained from the bitstream. Then, each of the two or more sets of segmentation information elements are inputted respectively into two or more segmentation information processing layers out of a plurality of cascaded layers. In each of the two or more segmentation information processing layers, the respective sets of segmentation information are processed. The decoded data for picture or video processing are obtained based on the segmentation information processed by the plurality of cascaded layers. Accordingly, the data may be decoded from the bitstream in an efficient manner in the layered structure.

Abstract: The present disclosure relates to methods and apparatuses for encoding data for (still or video processing into a bitstream). In particular, the data are processed by a network which includes a plurality of cascaded layers. In the processing, feature maps are generated by the layers. The feature maps processed (output) by at least two different layers have different resolutions. In the processing, a layer is selected, out of the cascaded layers, which is different from the layer generating the feature map of the lowest resolution (e.g. latent space). The bitstream includes information related to the selected layer. With this approach, scalable processing which may operate on different resolutions is provided so that the bitstream may convey information relating to such different resolutions. Accordingly, the data may be efficiently coded within the bitstream, depending on the resolution which may vary depending on the content of the picture data coded.

Abstract: The present disclosure relates to video encoding and decoding, and in particular to determining motion information for a current block using a history-based motion vector predictor, HMVP, list. The HMVP list is constructed, with said list being an ordered list of N HMVP candidates Hk, k=0, . . . , N?1, which are associated with motion information of N preceding blocks of the frame and precede the current block. Each HMVP candidate has motion information including elements of one or more motion vectors, MVs, one or more reference picture indices corresponding to the MVs, and one or more bi-prediction weight indices. One or more HMVP candidates from the HMVP list are added into a motion information candidate list for the current block; and the motion information is derived based on the motion information candidate list.

Abstract: A method for inverse quantization of a current block of a picture is provided. The method is performed by a decoder, and the picture comprises a luminance component and a chrominance component, where the luminance component and the chrominance component are partitioned into multiple blocks. The method includes obtaining one or more existing quantization parameter (QP) values from a received bitstream, wherein the one or more existing QP values are associated with a current block in the chrominance component; determining a QP value for the current block in the chrominance component based on the one or more existing QP values; performing inverse quantization on the current block in the chrominance component using the determined QP value.

Abstract: Apparatuses and methods for Intra Sub-Partitions (ISP) are provided. The method includes: obtaining information of ISP, and determining a size of a chroma transform block (TB) of the coding unit based on SubWidthC and SubHeightC when at least a first condition is fulfilled. The first condition includes the information of ISP indicates that ISP is used for splitting the luma coding block. SubWidthC and SubHeightC are variables depending on chroma format information. The chroma format information indicates a chroma format of a picture the coding unit belongs to. The method can apply to all chroma format. The chroma format includes at least one of: 4:2:0, or 4:2:2, or 4:4:4. An accurate and versatile way to determine the size of the chroma transform block for the ISP is achieved.

Abstract: The present disclosure relates to efficient signaling of feature map information for a system employing a neural network. In particular, at the decoder side, a presence indicator is obtained based on information parsed from a bitstream. Based on the value of the obtained presence indicator, further data related to a feature map region are parsed or the parsing is bypassed. The presence indicator may be, for instance, a region presence indicator indicating whether feature map data is included in the bitstream or may be a side information presence indicator indicating whether a side information related to the feature map data is included in the bitstream. Similarly, an encoding method, as well as encoding and decoding devices, are provided. Accordingly, feature map data may be processed more efficiently, by reducing decoding complexity, and the amount of transmitted data can be reduced by applying the bypassing.

Abstract: A method comprising obtaining a bitstream, the bitstream comprises a transform unit syntax and a coding unit syntax, the transform unit syntax includes a value of a first flag and a value of a second flag related to, respectively, a first chroma transform block and a second chroma transform block of a current transform unit or a current sub-transform unit within the current transform unit, the first or second flag specifies whether the first or second chroma transform block contains at least one transform coefficient levels not equal to 0, the coding unit syntax includes a value of a third flag specifying whether a transform tree structure is present or not; and deriving a value of a fourth flag based on the values of the first, second, and third flags, the fourth flag specifies whether a luma transform block contains at least one transform coefficient levels not equal to 0.

Abstract: A filter for video coding is configured for processing a block for generation of a filtered block, where the block comprises a plurality of pixels. The filter includes one or more processor configured to: scan a current pixel of the block and its neighboring pixels of the current pixel according to a predefined scan template, obtain spectrum components by performing transform for the current pixel and its neighboring pixels, obtain filtered spectrum components based on a filtering parameter and the spectrum components, obtain filtered pixels by performing inverse transform for the filtered spectrum components, and generate a filtered block based on the filtered pixels.

Abstract: A method for inverse quantization of a current block of a picture is provided. The method is performed by a decoder, and the picture comprises a luminance component and a chrominance component, where the luminance component and the chrominance component are partitioned into multiple blocks. The method includes obtaining one or more existing quantization parameter (QP) values from a received bitstream, wherein the one or more existing QP values are associated with a current block in the chrominance component; determining a QP value for the current block in the chrominance component based on the one or more existing QP values; performing inverse quantization on the current block in the chrominance component using the determined QP value.

Abstract: A method of coding is implemented by a decoding device, the method includes: receiving a bitstream, and obtaining from the bitstream, a first luma bit depth value of luma samples of a current picture. The method also includes performing a Hadamard Transform Domain Filtering (HTDF) post reconstruction filtering of a block of the current picture by using a lookup table based on the obtained first luma bit depth value.

Abstract: A prediction method for an image block comprising a first prediction sub-block and a second prediction sub-block, the prediction method comprising: parsing a first index from a bitstream, wherein the first index is used to obtain prediction information of the first prediction sub-block; parsing a second index from the bitstream; comparing the first index with the second index; adjusting the second index in the event that the second index is equal to or greater than the first index; and obtaining prediction information of the second prediction sub-block according to the adjusted second index.

Abstract: The present disclosure relates to methods and apparatuses for modifying a quantizer. In particular, within a preliminary set of quantization levels, at least one quantization level is modified based on optimization involving distortion for a predetermined set of input values. At least one another quantization level out of the preliminary set is not modified. The not modified (non-modifiable) quantization level is the minimum clipping value or the maximum clipping value. The modification may facilitate increasing the dynamic range of the quantized/inverse-quantized data. Such modified quantizer may be advantageous for employment in neural networks to compress their data such as feature maps or the like. It may improve accuracy of the neural network.

Abstract: The present disclosure relates to scalable encoding and decoding of pictures. In particular, a picture is processed by one or more network layers of a trained module to obtain base layer features. Then, enhancement layer features are obtained, e.g. by a trained network processing in sample domain. The base layer features are for use in computer vision processing. The base layer features together with enhancement layer features are for use in picture reconstruction, e.g. for human vision. The base layer features and the enhancement layer features are coded in a respective base layer bitstream and an enhancement layer bitstream. Accordingly, a scalable coding is provided which supports computer vision processing and/or picture reconstruction.

Abstract: A method for coding video data is disclosed. The method comprises: obtaining a center motion vector of a coding block; deriving a first motion vector range for the coding block based on the center motion vector and a motion vector spread, wherein the motion vector spread depends on a size of the coding block; if the first motion vector range is at least partially pointing outside a first area including a reference picture, updating the first motion vector range to point within the first area, such that a minimum value or a maximum value of the updated first motion vector range is pointing at a boundary of the first area.

Abstract: A prediction method for an image block comprising a first prediction sub-block and a second prediction sub-block, the prediction method comprising: parsing a first index from a bitstream, wherein the first index is used to obtain prediction information of the first prediction sub-block; parsing a second index from the bitstream; comparing the first index with the second index; adjusting the second index in the event that the second index is equal to or greater than the first index; and obtaining prediction information of the second prediction sub-block according to the adjusted second index.

Abstract: Reference picture management scheme is provided in the context of video coding. A method of decoding an encoded video sequence, comprising obtaining a value of a reference picture list (RPL) syntax element from a bitstream of the encoded video sequence, the RPL syntax element specifying whether syntax elements related to reference picture lists are present in the bitstream, when the RPL syntax element specifies that the syntax elements related to the reference picture lists are present in the bitstream, obtaining, from the bitstream, values of the syntax elements related to the reference picture lists; and constructing at least one reference picture list for inter prediction using the obtained values of the syntax elements related to the reference picture lists.

Abstract: A filter for video coding is provided, where the filter is configured for processing a block for generation of a filtered block, and the block comprises a plurality of pixels. The filter includes one or more processor configured to: scan, according to a predefined scan template, to obtain a current pixel of the block and its neighboring pixels of the current pixel; obtain spectrum components by performing transform for the current pixel and its neighboring pixels; obtain filtered spectrum components based on a filtering parameter and the spectrum components; obtain filtered pixels by performing inverse transform for the filtered spectrum components; and generate a filtered block based on the filtered pixels. The filter is provided allowing improving the efficiency for video coding.

Abstract: A method for decoding of a video bitstream implemented by a decoding device, wherein the video bitstream includes data representing one or more sequence parameter set, SPS, flags, the method comprising: for an SPS flag of the one or more SPS flags, obtaining two variables of the SPS flag, respectively, by parsing the video bitstream, wherein the value of one variable of the two variables is the minimum allowed value of the SPS flag, and wherein the value of the other variable of the two variables is the maximum allowed value of the SPS flag; obtaining the SPS flag, by parsing the video bitstream; evaluating whether the value of the SPS flag is valid based on the values of the two variables; and in case that the value of the SPS flag is valid, decoding the video bitstream according to the value of the SPS flag.

Abstract: Improved deriving and signaling of minimum and maximum block sizes in the context of partitioning processes is provided herein. In particular, it is provided a method of deriving a minimum coding block size implemented by a decoding device, comprising: parsing a value of a syntax element from a bitstream, deriving the binary logarithm of the minimum coding block size by adding 2 to the parsed value of the syntax element, and deriving the minimum block size from the derived binary logarithm of the minimum coding block size. Restrictions on the syntax element values related to the partitioning process are introduced to prevent undefined behavior and unpredictable code length in case of using variable length codes.

Abstract: The present disclosure relates to methods and apparatuses for encoding video data into a bitstream and for decoding video data received in a bitstream. A second control flag indicating whether or not to use multi-hypothesis prediction for intra and inter mode is generated and transmitted only conditionally, upon a determination whether or not separate merge list technique for subblock merge candidates is used. On the other hand, a decoder is capable of deciding usage of multi-hypothesis prediction for intra and inter mode and separate merge list technique for subblock merge candidates even though the second control flag is transmitted only conditionally.