Abstract: A point-cloud decoding device according to the present invention includes: a tree synthesizing unit configured to decode position information on each point of point-cloud data as a decoding target, and give, in ascending order in order of decoding of the position information, an index to each point of the point-cloud data.

Abstract: An image decoding device (200) includes: a merge unit (241A2) configured to apply geometric block partitioning merge to a target block divided in a rectangular shape, wherein the merge unit (241A2) includes: a merge mode specifying unit (241A21) configured to specify whether or not the geometric block partitioning merge is applied; a geometric block partitioning unit (241A22) configured to specify a geometric block partitioning pattern and further perform geometric block partitioning on the target block divided in the rectangular shape by using the specified geometric block partitioning pattern; and a merge list construction unit (241A23) configured to construct a merge list for the target block subjected to the geometric block partitioning and decode motion information.

Abstract: An image decoding device includes a prediction unit configured to generate a prediction signal included in a prediction block based on a motion vector. The prediction unit is configured to perform refinement processing of setting a search range based on a reference position specified by the motion vector, specifying a corrected reference position having the smallest predetermined cost from the search range, and correcting the motion vector based on the corrected reference position. When a block size of the prediction block is larger than a predetermined block size, the prediction unit is configured to divide the prediction block into sub-block groups and perform the refinement processing for each sub-block.

Abstract: An image decoding device includes: a motion vector decoding unit that decodes a motion vector from encoded data; a refinement unit that performs refinement processing to correct the decoded motion vector; and a predictive signal generation unit that generates a predictive signal on the basis of the corrected motion vector outputted from the refinement unit. The predictive signal generation unit determines whether or not to apply BDOF processing for each block, on the basis of information calculated in the course of the refinement processing.

Abstract: An image decoding device according to the present invention including a decoding unit configured to decode first syntax that controls transmission precision of a merge with motion vector difference in a sequence of a decoding target, wherein the value of the first syntax being “1” specifies that both fractional precision and integer precision could be used as the transmission precision of the merge with motion vector difference in the sequence of the decoding target, and the value of the first syntax being “0” specifies that the first syntax uses fractional precision as the transmission precision of a merge with motion vector difference in the sequence of the decoding target.

Abstract: A point-cloud decoding device 200 according to the present invention includes: a geometry information decoding unit 2010 configured to decode a flag that controls whether to apply “Implicit QtBt” or not; and an attribute-information decoding unit 2060 configured to decode a flag that controls whether to apply “scalable lifting” or not; wherein, a restriction is set not to apply the “scalable lifting” when the “Implicit QtBt” is applied.

Abstract: In an image decoding device 200 according to the present invention, a decoding unit 210 is configured to decode a flag indicating whether chroma-related syntax is included in a picture parameter set, and in a case where the flag indicates that chroma-related syntax is included in the picture parameter set, the decoding unit 210 is configured to decode syntax for controlling deblocking filter processing of a Cb signal and a Cr signal.

Abstract: An image decoding device includes: a block structure decoding unit configured to decode the coded data to acquire luminance block division information and chrominance block division information; a determination unit configured to determine whether or not a cross-component linear model method is applicable based on the luminance block division information and the chrominance block division information; and a chrominance intra-prediction method decoding unit configured to decode a chrominance intra-prediction method according to a result of the determination.

Abstract: A decoding device includes a transformer sets a decoded luminance component of a prediction target block to the same number of samples as that of the chrominance component corresponding to the decoded luminance component of the prediction target block and generates a luminance reference signal. A specificator specifies luminance pixels having minimum and maximum pixel values of the decoded luminance component adjacent to the decoded luminance component of the prediction target block, respectively, outputs luminance pixel values obtained from specified luminance pixels, and outputs chrominance pixel values from pigment pixels corresponding to the luminance pixels. A derivator derives a linear prediction parameter from the two pixel values and a linear prediction model. A chrominance linear predictor obtains chrominance prediction signal applying the linear prediction model based on the linear prediction parameter to the luminance reference signal.

Abstract: A decoding device includes a transformer sets a decoded luminance component of a prediction target block to the same number of samples as that of the chrominance component corresponding to the decoded luminance component of the prediction target block and generates a luminance reference signal. A specificator specifies luminance pixels having minimum and maximum pixel values of the decoded luminance component adjacent to the decoded luminance component of the prediction target block, respectively, outputs luminance pixel values obtained from specified luminance pixels, and outputs chrominance pixel values from pigment pixels corresponding to the luminance pixels. A derivator derives a linear prediction parameter from the two pixel values and a linear prediction model. A chrominance linear predictor obtains chrominance prediction signal by applying linear prediction model based on the linear prediction parameter to the luminance reference signal.

Abstract: An image decoding device includes a prediction unit configured to generate a prediction signal included in a prediction block based on a motion vector. The prediction unit is configured to perform refinement processing of setting a search range based on a reference position specified by the motion vector, specifying a corrected reference position having the smallest predetermined cost from the search range, and correcting the motion vector based on the corrected reference position. When a block size of the prediction block is larger than a predetermined block size, the prediction unit is configured to divide the prediction block into sub-block groups and perform the refinement processing for each sub-block.

Abstract: An image decoding device, includes a filter unit using, as an input, a decoded signal prior to the filtering process and output a filtered decoded signal. The filter unit performs clipping processing on the decoded signal prior to the filtering process such that the absolute value of a differential value between a reference pixel value and a pixel value of the decoded signal prior to the filtering process is less than or equal to a predefined threshold value, and to generate the filtered decoded signal through the linear weighted addition of the value after the clipping processing is performed and the pixel value of the decoded signal prior to the filtering process; and a large-small relationship between the threshold value for a luma signal and the threshold value for a chroma signal are defined such that the large-small relationship is unchanged when an internal bit depth is changed.

Abstract: A decoding-side first generation unit generating, for a target unit, a first component prediction sample. A decoding-side linear prediction unit using the first component sample and a prediction coefficient to generate a linear prediction sample of a second component. A decoding-side second generation unit using the second component linear prediction sample to generate, for the target unit, a second component prediction sample. The decoding-side linear prediction unit uses a first coefficient as the prediction coefficient when the first component sample is equal to or below a threshold value, and uses a second coefficient, different from the first, as the prediction coefficient when the first component sample is greater than the threshold value. The threshold value is set on a parameter representing a distribution or change in a reference sample of the first component and/or the second component contained in a reference unit referenced for the target unit.

Abstract: An image decoding device (200) includes: a motion vector decoding unit (241B) configured to decode a motion vector from coded data; and a refinement unit (241C) configured to search for the motion vector with a value of the motion vector decoded by the motion vector decoding unit (241B) as an initial value, and set the decoded motion vector as a final motion vector in a case where a searching cost at an initial searched point is larger than a predetermined threshold value or in a case where the searching cost at the initial searched point is equal to or larger than the threshold value.

Abstract: A moving-image decoder includes a decoding means configured to decode a bitstream representing a moving image including a block encoded using intra-prediction, an inverse processing means configured to generate difference values in pixels of the block by inverse-quantizing and inverse-transforming a level value of the block obtained from a result of decoding, an intra-prediction means configured to generate predicted values of pixels of the block according to intra-prediction based on pixel values of reconstructed blocks around the block, and a reconstruction means configured to reconstruct the block on the basis of the generated difference values and the generated predicted values, wherein the intra-prediction means is configured to generate a reference line for use in the intra-prediction by synthesizing a plurality of lines of the reconstructed blocks around the block.

Abstract: An image decoding device includes a prediction unit configured to generate a prediction signal included in a prediction block based on a motion vector. The prediction unit is configured to perform refinement processing of setting a search range based on a reference position specified by the motion vector, specifying a corrected reference position having the smallest predetermined cost from the search range, and correcting the motion vector based on the corrected reference position. When a block size of the prediction block is larger than a predetermined block size, the prediction unit is configured to divide the prediction block into sub-block groups and perform the refinement processing for each sub-block.

Abstract: A decoding device includes a transformer sets a decoded luminance component of a prediction target block to the same number of samples as that of the chrominance component corresponding to the decoded luminance component of the prediction target block and generates a luminance reference signal. A specificator specifies luminance pixels having minimum and maximum pixel values of the decoded luminance component adjacent to the decoded luminance component of the prediction target block, respectively, outputs luminance pixel values obtained from specified luminance pixels, and outputs chrominance pixel values from pigment pixels corresponding to the luminance pixels. A derivator derives a linear prediction parameter from the two pixel values and a linear prediction model. A chrominance linear predictor obtains a chrominance prediction signal by applying the linear prediction model based on the linear prediction parameter to the luminance reference signal.

Abstract: An image decoding device, includes a filter unit using, as an input, a decoded signal prior to the filtering process and output a filtered decoded signal. The filter unit performs clipping processing on the decoded signal prior to the filtering process such that the absolute value of a differential value between a reference pixel value and a pixel value of the decoded signal prior to the filtering process is less than or equal to a predefined threshold value, and to generate the filtered decoded signal through the linear weighted addition of the value after the clipping processing is performed and the pixel value of the decoded signal prior to the filtering process; and a large-small relationship between the threshold value for a luma signal and the threshold value for a chroma signal are defined such that the large-small relationship is unchanged when an internal bit depth is changed.

Abstract: An image decoding device includes: a chroma quantization parameter offset initialization unit configured to initialize a chroma offset based on a result of decoding coded data; a chroma offset deriving unit configured to set and derive the chroma offset based on the result of decoding the coded data; a chroma deriving unit configured to derive a chroma based on the chroma offset derived by the chroma offset deriving unit; and a coding unit level chroma QP initialization unit configured to initialize the chroma QP offset for each coding unit that is not recursively partitioned.

Abstract: An image decoding device includes a quantization parameter deriving unit configured to correct a value of a decoded quantization parameter of a target block depending on whether or not adaptive color transform has been applied to the target block, and then set, as the quantization parameter of the target block, the larger of the corrected value of the quantization parameter and a predetermined value of “0” or more.