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: According to one embodiment, an image encoding method includes selecting a motion reference block from an encoded pixel block to which an inter prediction is applied. The method includes selecting one or more available blocks from the motion reference block. The method includes selecting a selection block from the available blocks. 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 specifying the selection block by referring to a code table decided according to a number of the available blocks.

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: The coding efficiency and the amount of processing can be further improved in methods that use the correlation between spatial and temporal directions to estimate parameters that are required for predictions. In LM prediction that predicts pixel values of chrominance, based on pixel values of luminance, an index for a filter that downsamples a luminance image is adaptively signalled.

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: 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 image decoding apparatus includes a decoding unit configured to decode coded data into a decoded image and segmentation metadata, a segmentation metadata decoding unit configured to generate segmentation information, and an image processing unit configured to perform prescribed image processing on the decoded image with reference to the segmentation information.

Abstract: According to one embodiment, an image encoding method includes selecting a motion reference block from an encoded pixel block to which an inter prediction is applied. The method includes selecting one or more available blocks from the motion reference block. The method includes selecting a selection block from the available blocks. 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 specifying the selection block by referring to a code table decided according to a number of the available blocks.

Abstract: According to an embodiment, an image coding method is for coding an image including a luminance component and color difference components. The method includes acquiring a reference image; and generating a predicted image by interpolating the luminance component and the color difference components in the reference image according to a motion vector. If a size of a block, which is designated as a unit of the interpolation, is equal to or smaller than a predetermined first threshold value, the generating includes inhibiting a bi-directional prediction, and performing only a uni-directional prediction to generate the predicted image according to the motion vector.

Abstract: According to an embodiment, an image coding method is for coding an image including a luminance component and color difference components. The method includes acquiring a reference image; and generating a predicted image by interpolating the luminance component and the color difference components in the reference image according to a motion vector. If a size of a block, which is designated as a unit of the interpolation, is equal to or smaller than a predetermined first threshold value, the generating includes inhibiting a bi-directional prediction, and performing only a uni-directional prediction to generate the predicted image according to the motion vector.

Abstract: According to an embodiment, an encoding device includes an index setting unit and an encoding unit. The index setting unit generates a common index in which reference indices of one or more reference images included in a first index and a second index are sorted in a combination so as not to include a same reference image in accordance with a predetermined scanning order. The first index representing a combination of the one or more reference images referred to by a first reference image. The second index representing a combination of the one or more reference images referred to by a second reference image. The encoding unit encodes the common index.

Abstract: According to an embodiment, an encoding device includes an index setting unit and an encoding unit. The index setting unit generates a common index in which reference indices of one or more reference images included in a first index and a second index are sorted in a combination so as not to include a same reference image in accordance with a predetermined scanning order. The first index representing a combination of the one or more reference images referred to by a first reference image. The second index representing a combination of the one or more reference images referred to by a second reference image. The encoding unit encodes the common index.

Abstract: According to an embodiment, an encoding device includes an index setting unit and an encoding unit. The index setting unit generates a common index in which reference indices of one or more reference images included in a first index and a second index are sorted in a combination so as not to include a same reference image in accordance with a predetermined scanning order. The first index representing a combination of the one or more reference images referred to by a first reference image. The second index representing a combination of the one or more reference images referred to by a second reference image. The encoding unit encodes the common index.

Abstract: According to an embodiment, an encoding device includes an index setting unit and an encoding unit. The index setting unit generates a common index in which reference indices of one or more reference images included in a first index and a second index are sorted in a combination so as not to include a same reference image in accordance with a predetermined scanning order. The first index representing a combination of the one or more reference images referred to by a first reference image. The second index representing a combination of the one or more reference images referred to by a second reference image. The encoding unit encodes the common index.

Abstract: According to an embodiment, an encoding device includes an index setting unit and an encoding unit. The index setting unit generates a common index in which reference indices of one or more reference images included in a first index and a second index are sorted in a combination so as not to include a same reference image in accordance with a predetermined scanning order. The first index representing a combination of the one or more reference images referred to by a first reference image. The second index representing a combination of the one or more reference images referred to by a second reference image. The encoding unit encodes the common index.

Abstract: According to an embodiment, 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: 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 value limiting filter includes a color space transform processing unit configured to transform an input image signal defined by a color space into an image signal of another color space, a clipping processing unit configured to perform processing of limiting a pixel value of the transformed image signal, and a color space inverse transform processing unit configured to transform the image signal having the limited pixel value into the image signal of the original color space.

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: According to an embodiment, an image coding method is for coding an image including a luminance component and color difference components. The method includes acquiring a reference image; and generating a predicted image by interpolating the luminance component and the color difference components in the reference image according to a motion vector. If a size of a block, which is designated as a unit of the interpolation, is equal to or smaller than a predetermined first threshold value, the generating includes inhibiting a bi-directional prediction, and performing only a uni-directional prediction to generate the predicted image according to the motion vector.