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: To achieve a reduction in the amount of coding taken in the use of an asymmetric partition and to implement efficient encoding/decoding processes exploiting the characteristics of the asymmetric partition. An image decoding device includes a motion compensation parameter derivation unit configured to derive a motion compensation parameter indicating either a uni-prediction scheme or a bi-prediction scheme. In a case that a prediction unit has a size less than or equal to a predetermined value, the motion compensation parameter derivation unit is configured to derive the motion compensation parameter by switching between the prediction schemes.

Abstract: A coding device and a decoding device are configured to include an estimated prediction mode deciding section (122a) including: a reference block selecting section (1223a) for selecting a reference block for use in estimating an intra-prediction mode for a subject block; an estimating number deciding section (1222a) for deciding an estimating number of estimated values to be estimated for the intra-prediction mode; and an estimated prediction mode deriving section (1221a) for estimating, based on a reference block, the estimating number of estimated values of the prediction mode.

Abstract: A video decoding apparatus (31) for splitting an image into tiles, splits a tile of the tiles into coding tree units (CTUs), and decodes a video on a per-CTU basis, the video decoding apparatus including a header decoder (3020) configured to decode tile unit information indicating a unit for a size of a tile from header information of a coding stream, and a coding tree (CT) decoder (3021) configured to split the tile into CTUs, wherein the header decoder derives a tile upper left position and a tile size by using the tile unit information.

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: Delay based on WPP processing is reduced. An image decoding apparatus (31) includes: a prediction image generation unit (308) by using decoded data from a first position to a second position, the first position being, in a CTU row immediately above a CTU row including a target CTU, identical to a position of the target CTU, the second position being a position one CTU forward relative to the first position; and an entropy decoding unit (301) that performs decoding of the target CTU by using the decoded data from the first position to the second position, the first position being, in the CTU row immediately above the CTU row including the target CTU, identical to the position of the target CTU, the second position being a position one CTU forward relative to the first position.

Abstract: In a scheme in which only a part of one picture is intra-predicted and the rest of the region is inter-predicted, generation of a significant code amount and generation of a delay can be avoided in a specific picture. However, because only a part of the picture is coded by means of the intra prediction, coding efficiency is deteriorated as compared to an I picture in which the entire picture is coded by means of the intra prediction. A picture is split into a restricted region and a non-restricted region. Prediction is performed by using an intra prediction in which only a pixel of the restricted region is referred to or an inter prediction in which a restricted reference region of a reference picture is referred to for a block of the restricted region. Prediction is performed by using the intra prediction in which a decoded pixel in the picture is referred to or the inter prediction in which the reference picture is referred to for the block of the non-restricted region.

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 frequency transformation determination unit determines whether a plurality of adjacent transformation target regions with the partition boundary interposed therebetween are integrated or not. A transformation coefficient generation unit generates, by applying one frequency transformation, a transformation coefficient for the transformation target regions where the frequency transformation determination unit determined to integrate.

Abstract: To suppress an overhead of a flag indicating a motion compensation filter. A motion compensation filter apparatus includes a motion compensation filter unit configured to switch a filter to apply on a full sample image in a certain unit, and an MC filter parameter derivation unit configured to select a switching unit for filter switching by the motion compensation filter unit.

Abstract: An adaptive motion vector prediction unit configured to adaptively perform spatial prediction that performs prediction using a motion vector around a target block and temporal prediction that performs prediction using a motion vector of a collocated picture is included, and in the temporal prediction performed by the adaptive motion vector prediction unit, the collocated picture to be referred to is designated on a per picture basis, and a reference list is designated on a per slice basis.

Abstract: An image decoding device (31) includes a transform coefficient decoding unit (311) configured to decode a transform coefficient for a transform tree included in a coding unit. In the transform tree, the transform coefficient decoding unit splits a transform unit corresponding to luminance and then decodes the transform coefficient related to the luminance, and does not split the transform unit corresponding to chrominance and decodes the transform coefficient related to the chrominance.

Abstract: An image decoding apparatus is provided with a CT information decoding unit that decodes division information indicating a division method for binary tree division with respect to a coding node of a coding tree unit, and performs the binary tree division with respect to the coding node by referring to the division information of another decoded coding node.

Abstract: An image coding apparatus includes a coded data generating unit configured to generate coded data including image data for a subpicture acquired by dividing a picture, where the coded data generating unit generates, on a per subpicture basis, a subpicture header including subpicture identification information used for identifying the subpicture, and causes the generated subpicture header to be included in the coded data.

Abstract: An image decoding apparatus includes: an MPM candidate list deriving unit that derives an MPM candidate list by adding a plurality of different intra prediction modes to the MPM candidate list based on a shape of a target block, and an MPM parameter decoding unit decoding parameters for deriving the intra-prediction modes from the MPM candidate list.

Abstract: A video encoding device (2) includes a side information determination section (21) and a side information encoding section (22). The side information determination section (21) sets a quantization parameter for each macroblock in such a manner that a difference between quantization parameters for each pair of macroblocks with successive encoding orders is equal to one of n difference values, and transforms the difference into one of n indices with respect to each pair. The side information encoding section (22) generates a binary sequence having a length corresponding to the size of the absolute value of the index. The total of absolute values of the n indices is smaller than the total of absolute values of the n difference values.

Abstract: A video decoding apparatus includes: a matrix reference pixel derivation unit configured to derive, as a reference image, an image obtained by down-sampling an image adjacently above a target block and an image adjacently leftward of the target block; a weight matrix derivation unit configured to derive a matrix of weighting factors in accordance with an intra prediction mode and a target block size; a matrix prediction image derivation unit configured to derive a prediction image by using a product of elements of the reference image and elements of the matrix of the weighting factors; and a matrix prediction image interpolation unit deriving, as a prediction image, the prediction image or an image obtained by interpolating the prediction image, wherein the weight matrix derivation unit derives a matrix with a size of a width equal to or smaller than a width of the target block size and a height equal to or smaller than a height of the target block size.

Abstract: The amount of processing is reduced with high coding efficiency maintained. There is provided an arithmetic decoding device including syntax decoding means for decoding each of at least a first syntax element and a second syntax element indicating a transform coefficient using arithmetic decoding with a context or arithmetic decoding without a context. The syntax decoding means performs decoding that at least includes not decoding the first syntax element and decoding the second syntax element using the arithmetic decoding without a context, and decoding the first syntax element using the arithmetic decoding with a context and decoding the second syntax element using the arithmetic decoding without a context.

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 load in processing of searching for a motion vector is reduced. In order to solve the problem described above, a motion vector derivation apparatus (3032, 3036 to 3038) 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 (30373) configured to search for a motion vector on a prediction unit basis through matching processing. The motion vector search unit (30373) 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.