Abstract: An image decoding apparatus includes: a first filter unit configured to apply a first filter to an image (a luminance image and a chrominance image); a second filter unit configured to apply a second filter to an output image of the first filter; a filter set derivation unit configured to decode a filter coefficient from coded data; and a third filter unit configured to apply a third filter to an output image of the second filter by using the filter coefficient. In a case that the third filter unit performs filter processing for the luminance image by using a luminance output image of the second filter, the third filter unit performs processing of clipping an amount of change of a pixel value through the filter processing within a prescribed range of value.

Abstract: A method for signaling gradual refresh for encoding a set of pictures performed by an electronic device is provided. The method identifies a first picture in the set of pictures as being associated with a gradual refreshed picture, and stores a network abstraction layer (NAL) unit type in a coded stream associated with the first picture. The NAL unit type identifies a presence of the gradual refreshed picture. The method then stores, in the coded stream, an enable flag to identify a use of the gradual refresh for encoding at least a subset of pictures in the set of pictures.

Abstract: Object Known derivation, on a per intra prediction modes basis, of a template-based intra mode derivation based on a difference between a template prediction image and a template image has a problem that derivation of the template image and cost calculation require great computational resources. Solution Included are an intra prediction image generation unit configured to generate a template prediction image for an intra prediction mode candidate predetermined, a template cost derivation unit configured to derive a cost from the template prediction image and a template image corresponding to an image near a target block, and an intra prediction image generation unit configured to generate an intra prediction image by using a selected intra prediction mode, wherein the number of taps of an interpolation filter for the template prediction image is less than the number of taps of an interpolation filter for intra prediction.

Abstract: Object Known derivation, in units of intra prediction modes, of a template-based intra prediction mode based on a difference between a template prediction image and a template image has a problem that derivation of the template image and cost calculation require great computational resources. Solution An image decoding apparatus includes an intra prediction image generation unit configured to generate a template prediction image for a prescribed intra prediction mode candidate, a template cost derivation unit configured to derive a cost from the template prediction image and a template image corresponding to an image near a target block, and an intra prediction image generation unit configured to generate an intra prediction image by using a selected intra prediction mode, and a reference sample is sampled that is used to generate the template prediction image.

Abstract: Object In the existing specifications for neural network post-filter characteristics SEI, in order to perform post-filtering processing, the SEI needs to be transmitted for each picture, which presents a problem of redundancy in a case that the same post-filtering processing is performed in all of pictures. Solution A video decoding apparatus according to an aspect of the present invention includes an image decoding apparatus configured to decode coded data and generate a decoded image, an inverse conversion information decoding apparatus configured to decode inverse conversion information as supplemental enhancement information on a per sequence basis, and a resolution inverse conversion apparatus configured to conversion the decoded image to an image with an indicated resolution by using the inverse conversion information, the resolution inverse conversion apparatus using a neural network.

Abstract: Object A video coding and decoding apparatus that can enhance coding efficiency is provided. Solution A video decoding apparatus includes an OOB determination unit configured to determine whether a reference block is a target of OOB processing by comparing coordinates of the reference block with coordinates of a picture, and an OOB mask derivation unit configured to derive mask data indicating whether a pixel is available by comparing coordinates of the pixel included in the reference block with the coordinates of the picture. The OOB determination unit determines whether the reference block is the target of the OOB processing based on presence or absence of processing to be applied to a reference picture including the reference block.

Abstract: A reference picture information decoding unit (13) omits decoding of a reference list sorting presence or absence flag and/or a reference list sorting order based on the number of current picture referable pictures.

Abstract: A mechanism is provided that implements video coding and decoding such that only a specific partial image region on a screen can be independently decoded. A video decoding apparatus (31) according to an aspect of the present invention configures, in intra prediction, inter prediction, loop filter processing, or the like, a partial image region in a picture, handles a region outside the partial image region in a similar manner to a region outside the picture, and does not apply such restriction to a non-partial image region other than the partial image region in the picture.

Abstract: A video decoding apparatus includes matrix reference pixel derivation circuitry that derives reference samples by using top neighboring samples and left neighboring samples of a current block, weight matrix derivation circuitry that derives a weight matrix, matrix prediction image derivation circuitry that derives a prediction image, and matrix prediction image interpolation circuitry that derives a predicted image by using the prediction image. A size index is derived according to a value of a target block width and a value of a target block height. A prediction size is derived using the size index. In a case that a first condition, that both the value of the transform block width and the value of the transform block height are equal to 4, is true, the size index is set equal to 0 and the prediction size is set equal to 4.

Abstract: Provided is a video decoding apparatus for decoding coded data of a tile group in which a picture is split into rectangular regions, the tile group being composed of segments, the video decoding apparatus including: a header decoder configured to decode the number of tiles, a WPP enabled flag, and a slice enabled flag indicating whether segments in a target tile group are rectangular tiles, CTU rows, or slices from a tile group header, wherein the header decoder is configured to decode only one of the number of tiles being two or more, the WPP enabled flag being 1, and the slice enabled flag being 1 in one tile group.

Abstract: A video decoding apparatus includes an image decoding apparatus configured to decode coded data to generate a decoded image, and a resolution inverse conversion apparatus configured to convert a resolution of the decoded image to a specified resolution by using inverse conversion information. The resolution inverse conversion apparatus uses a neural network. In the resolution inverse conversion apparatus, information, indicating a number of horizontal pixels and a number of vertical pixels of a patch size being a unit of processing of the neural network, is decoded. The number of horizontal pixels and the number of vertical pixels of the decoded image are set equal to a maximum value of the number of horizontal pixels and a maximum value of the number of vertical pixels of the patch size, respectively.

Abstract: An adaptive offset filter (60) adds an offset to the pixel value of each pixel forming an input image. The adaptive offset filter (60) refers to offset-type specifying information, sets offset attributes for a subject unit area of the input image, decodes an offset having a bit width corresponding to an offset value range included in the set offset attributes, and adds the offset to the pixel value of each pixel forming the input image.

Abstract: Provided is a video decoding apparatus for decoding coded data of a tile group in which a picture is split into rectangular regions, the tile group being composed of segments, the video decoding apparatus including: a header decoder configured to decode the number of tiles, a WPP enabled flag, and a slice enabled flag indicating whether segments in a target tile group are rectangular tiles, CTU rows, or slices from a tile group header, wherein the header decoder is configured to decode only one of the number of tiles being two or more, the WPP enabled flag being 1, and the slice enabled flag being 1 in one tile group.

Abstract: A video decoding apparatus includes matrix reference pixel derivation circuitry that derives reference samples by using top neighboring samples and left neighboring samples of a current block, weight matrix derivation circuitry that derives a weight matrix, matrix prediction image derivation circuitry that derives a prediction image, and matrix prediction image interpolation circuitry that derives a predicted image by using the prediction image. A size index is derived according to a value of a target block width and a value of a target block height. A prediction size is derived using the size index. In a case that a first condition, that both the value of the transform block width and the value of the transform block height are equal to 4, is true, the size index is set equal to 0 and the prediction size is set equal to 4.

Abstract: The amount of memory required for CCLM prediction is reduced. The CCLM prediction parameter derivation unit (310442) derives a scale shift value corresponding to a luma difference value, and derives a CCLM prediction parameter, by shifting, by using the scale shift value, a value obtained by multiplying a value of a table referred to with a value obtained by performing right shift of the luma difference value by the scale shift value as an index and a chroma difference value. In addition, in a case of deriving a prediction image, a bit width is reduced by adaptively deriving a shift amount of a linear prediction parameter from the chroma difference value.

Abstract: In a case of referring to information between pictures by means of inter prediction, the entire picture needs to be decoded even in a case of decoding a small region. In a case of referring to information within a picture by means of intra prediction, referring to information across a tile boundary is not possible. In a case that a pixel pointed by a sub-block level motion vector of a target block that is calculated by scaling based on an available motion vector acquired from a spatial neighboring block or a temporal neighboring block is not present within a tile sequence, a process of replacing the pixel value with a pixel value within the tile sequence is performed. In a case of referring to a pixel outside of a tile by means of intra prediction, a process of replacing the pixel value with that of a pixel within the tile is performed.

Abstract: Object There is the problem in the related art that the relationship between a patch size which is a unit of processing of a neural network and the sizes of input and output pictures is not clearly defined.

Abstract: An apparatus includes an inter prediction unit configured to decode multiple reference picture list structures and to select one reference picture list structure from the multiple reference picture list structures on a per picture basis or on a per slice basis, wherein in the multiple reference picture list structures, the number of all reference pictures is one or more.

Abstract: Complexity of coding/decoding of a video is reduced. An image decoding apparatus (31) includes a CN information decoder (10) configured to hierarchically split a coding node by at least any of binary tree split and ternary tree split. The CN information decoder refers to a method of splitting an immediately higher node, which is a node one generation higher than a target node, to restrict a method of splitting the target node.

Abstract: A load in processing of searching for a motion vector is reduced. In order to solve the problem described above, a motion vector derivation apparatus according to one aspect of the present invention that derives a motion vector to be referred to for generating a prediction image to be used for coding or decoding of a video includes a motion vector search unit configured to search for a motion vector on a prediction unit basis through matching processing. The motion vector search unit is configured to stop search of the motion vector, depending on whether or not a conditional expression according to a pixel bit-depth is satisfied.