Abstract: In a case that two reference picture lists are selected with one index value, the reference picture lists may not be determinable depending on the number of two reference picture list structures. Provided is a prediction unit that decodes a reference picture list structure including multiple reference picture lists and selects two reference picture lists from the reference picture list structure for each picture or for each slice. The prediction unit selects two reference picture lists with one index value depending on the number of two reference picture list structures.

Abstract: An image decoding apparatus is implemented that can suppress a decrease in coding efficiency in a case that a high compression rate is achieved. The image decoding apparatus includes a parameter decoder, and the parameter decoder decodes a skip flag indicating whether a skip mode is applied, and in a case that the skip flag does not indicate the skip mode, decodes a merge flag indicating whether a merge mode is applied, and in a case that the merge flag does not indicate the merge mode, decodes an MMVD flag indicating whether an MMVD mode is applied.

Abstract: In the related art, in some cases the weighted prediction processing is performed even in a case that normal prediction processing is to be performed. A video decoding apparatus includes a weighted prediction processing unit configured to decode a weight coefficient and an offset value from coded data and to generate a prediction image by multiplying an interpolation image by the weight coefficient and adding the offset value to the interpolation image, and a normal prediction processing unit configured to generate a prediction image from the interpolation image. In a case that in the weighted prediction processing unit, a bi-prediction is performed and information of the weight coefficient and the offset value is absent for both a reference list 0 and a reference list 1, the normal prediction processing unit generates a bi-prediction image.

Abstract: In a case that a model parameter suitable for an input video is selected from a set of prescribed model parameters and that resolution inverse conversion to be applied is performed, a video unsuitable for multiple model parameters may have lower quality. Included are an image decoding apparatus configured to decode coded data obtained by coding an image subjected to resolution conversion and filter information for deriving a first model parameter and a post-processing apparatus configured to perform conversion into the same resolution as an input image signal by using the image and the filter information decoded by the image decoding apparatus. Included are a composite information creating apparatus configured to create filter information for deriving the first model parameter and an image coding apparatus configured to code the image pre-processed in the resolution conversion or the like, and the filter information created by the composite information creating apparatus.

Abstract: A WP prediction and a GBI prediction are adaptively used in combination. A video decoding apparatus (31) includes: a weighted prediction unit (3094) configured to generate a prediction image by using at least one of a weight coefficient or an offset configured for a first unit region and a weight coefficient configured for a second unit region different from the first unit region, the weight coefficient and the offset each being applied to a pixel value included in one or a plurality of reference images.

Abstract: An encoding device includes a deriving unit and an encoding unit. The deriving unit is configured to derive a first reference value based on fixed point precision representing roughness of a weighting factor that is used for multiplying a reference image. The encoding unit is configured to encode a first difference value that is a difference value between the weighting factor and the first reference value and the fixed point precision. The weighting factor is included in a first range of predetermined bit precision having the first reference value at approximate center. The first difference value is in the predetermined range.

Abstract: A non-transitory machine-readable medium of an electronic device that stores one or more computer-executable instructions is provided. The one or more computer-executable instructions, when executed by at least one processing unit of the electronic device, cause the electronic device to: decode a wavefront parallel processing (WPP) enabled flag that indicates whether a rectangular tile or a coding tree unit (CTU) row having a height of one CTU exists in a segment in an object tile group; and decode an end bit of the segment. When the WPP enabled flag is 1, after decoding a CTU at a right end of the CTU row, an end bit of a first segment having a first fixed value is decoded. When the WPP enabled flag is 0, after decoding a CTU at a bottom right of a tile, an end bit of a second segment having a second fixed value is decoded.

Abstract: According to one embodiment, an image encoding method includes selecting a motion reference block from an already-encoded pixel block. The method includes selecting an available block including different motion information from the motion reference block, and selecting a selection block from the available block. The method includes generating a predicted image of the encoding target block using motion information of the selection block. The method includes encoding a prediction error between the predicted image and an original image. The method includes encoding selection information identifying the selection block by referring to a code table decided according to a number of the available block.

Abstract: A method of dividing an input image signal into pixel blocks, and performing inter-prediction on the divided pixel blocks. This method includes selecting predicted motion information from a motion information buffer storing motion information in an encoded region, and predicting motion information of an encoding target block by using the predicted motion information. The method further includes acquiring representative motion information from a plurality of items of motion information in an encoded region in accordance with first information indicating a method of selecting the predicted motion information, thereby obtaining only the representative motion information.

Abstract: An image decoding apparatus and an image coding apparatus that reduce complexity of high image quality processing are implemented. The image decoding apparatus includes an inter prediction parameter decoding processing unit that includes processing of, regarding two motion vectors, modifying the two motion vectors from an error of two prediction images. In a case that neither of the two prediction images is a case of weighted prediction, the processing of modifying the two motion vectors is performed.

Abstract: In a video coding and decoding method, in a case that a transmission rate is low, image quality is deteriorated due to coding distortion, but the image quality can be improved owing to post-filter processing using a neural network. However, a problem is that there may be no method of defining a strength control value to be input in the post-filter processing. A video decoding apparatus according to an aspect of the present invention includes an image decoding apparatus that generates a decoded image, and a post-filter processing apparatus that performs post-filter processing on the decoded image. In accordance with an input format for luminance and chrominance of the decoded image to be input in the post-filter processing, a strength control value obtained in a process of generating the decoded image is transformed, and the post-filter processing is performed.

Abstract: In a case that two reference picture lists are selected with one index value, the reference picture lists may not be determinable depending on the number of two reference picture list structures. Provided is a prediction unit that decodes a reference picture list structure including multiple reference picture lists and selects two reference picture lists from the reference picture list structure for each picture or for each slice. The prediction unit selects two reference picture lists with one index value depending on the number of two reference picture list structures.

Abstract: In the related art, in some cases the weighted prediction processing is performed even in a case that normal prediction processing is to be performed. A video decoding apparatus includes a weighted prediction processing unit configured to decode a weight coefficient and an offset value from coded data and to generate a prediction image by multiplying an interpolation image by the weight coefficient and adding the offset value to the interpolation image, and a normal prediction processing unit configured to generate a prediction image from the interpolation image. In a case that in the weighted prediction processing unit, a bi-prediction is performed and information of the weight coefficient and the offset value is absent for both a reference list 0 and a reference list 1, the normal prediction processing unit generates a bi-prediction image.

Abstract: Use of only supplemental enhancement information of a deep learning post-filter cannot adjust a filter strength in a case that each frame has a different image feature, thus reducing image quality improvement performance. A decoding apparatus for decoding coded data includes a header decoder that decodes supplemental enhancement information of a deep learning post-filter from the coded data, an attribute image decoder that decodes an attribute image from the coded data, and an attribute image filter unit that performs filtering processing of the attribute image, wherein the header decoder decodes objective information indicating that the attribute image filter unit is to perform filtering processing on the attribute image.

Abstract: An image decoding apparatus is implemented that can suppress a decrease in coding efficiency in a case that a high compression rate is achieved. The image decoding apparatus includes a parameter decoder, and the parameter decoder decodes a skip flag indicating whether a skip mode is applied, and in a case that the skip flag does not indicate the skip mode, decodes a merge flag indicating whether a merge mode is applied, and in a case that the merge flag does not indicate the merge mode, decodes an MMVD flag indicating whether an MMVD mode is applied.

Abstract: A video converting apparatus includes an image buffer unit configured to store multiple images, a super-resolution processing unit configured to perform super-resolution processing on an image input from the image buffer unit to output a super-resolution image, and a prediction image generation unit configured to reference the super-resolution image output by the super-resolution processing unit to generate a prediction image.

Abstract: A moving image decoding method is provided for decoding encoded data of a tile group generated by splitting a picture into one or more rectangular regions. The tile group includes one or more segments. The moving image decoding method includes decoding a wavefront parallel processing (WPP) enabled flag indicating whether a rectangular tile or a coding tree unit (CTU) row having a height of one CTU exists in a segment in an object tile group; and decoding an end bit of the segment. When the WPP enabled flag is 1, after decoding a CTU at a right end of the CTU row, an end bit of a first segment having a first fixed value is decoded. When the WPP enabled flag is 0, after decoding a CTU at a bottom right of a tile, an end bit of a second segment having a second fixed value is decoded.

Abstract: According to an embodiment, a decoding device includes an acquiring unit configured to acquire first format information, encoded data, and first filter information, the first format information indicating a resolution of a color-difference component of the encoded data; a decoding unit configured to decode the encoded data to obtain a decoded image; and a converting unit configured to convert a color-difference format of the decoded image represented by a first color-difference format by using a filter identified by the filter information.

Abstract: A 3D data decoding apparatus for decoding coded data. The 3D data decoding apparatus includes an arithmetic decoder configured to arithmetically decode mesh displacement from the coded data, a context selection unit configured to select a context in the arithmetic decoding, and a context initialization unit configured to set an initial value of the context. In the context initialization unit, a context initialization parameter for initializing the context is decoded from the coded data.

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.