Abstract: An image encoding device (1) includes a motion compensation predictor (109) configured to generate a prediction image corresponding to a target image by performing motion compensation prediction using a plurality of reference images, and an evaluator (111) configured to evaluate prediction accuracy of the prediction image for each image portion including one or more pixels by calculating a degree of similarity between the plurality of reference images for each image portion.

Abstract: An encoding device 1 includes: a transformer 13 configured to calculate an orthogonal transform coefficient by performing an orthogonal transformation process on a residual image indicating a difference between the input image and a predicted image of the input image; a quantizer 14 configured to generate quantization coefficient by quantizing the orthogonal transform coefficient based on a quantization parameter; an entropy encoder 24 configured to generate encoded data by encoding the quantization coefficient; an image decoder 10 configured to restore an orthogonal transform coefficient from the quantization coefficient based on the quantization parameter and generate a pre-filtering image by adding the predicted image to a residual image restored by performing inverse orthogonal transformation on the orthogonal transform coefficient; and a deblocking filter 18 configured to perform a filtering process on the pre-filtering image and control a filtering strength depending on a result of comparison between a

Abstract: An image encoding device (1) according to a first feature encodes blocks obtained by dividing an original image of a frame included in a video. The image encoding device (1) includes a code amount allocator (180) configured to allocate a code amount to each of a plurality of intra prediction modes defined in advance, a mode selector (171) configured to select an intra prediction mode to be applied to a target block of intra prediction from among the plurality of intra prediction modes, and an encoder (130) configured to encode identification information indicating the selected intra prediction mode in accordance with the allocated code amount. The code amount allocator (180) calculates a feature amount of a plurality of reference pixels adjacent to the target block and changes a manner of allocation of code amounts to the plurality of intra prediction modes based on the calculated feature amount.

Abstract: An image encoding device (1) includes the cross-component intra predictor (171a) generates a predicted chroma block through cross-component intra prediction in which a chroma block to be encoded is predicted by referring to, as the neighbouring decoded pixels adjacent to the chroma block, decoded luminance pixels and decoded chroma pixels, a candidate generator (181) configured to generate candidates for an orthogonal transform type to be applied to orthogonal transform processing on prediction residuals that represent errors between the predicted chroma block and the chroma block; and a transformer (121) configured to perform the orthogonal transform processing on the chroma prediction residuals by using an orthogonal transform type selected from among the candidates generated by the candidate generator (181).

Abstract: An intra prediction device predicts, by intra prediction, a luminance block and a chrominance block obtained by dividing an image. The intra prediction device includes a cross-component linear model predictor configured to predict the chrominance block from a decoded luminance block at a position corresponding to a position of the chrominance block using a linear model calculated from respective luminance and chrominance reference pixels around the chrominance block. The cross-component linear model predictor includes a reference pixel position selector configured to select linear model calculation pixel positions that are positions of the reference pixels to be used to calculate the linear model based on a luminance intra prediction mode that is an intra prediction mode applied to the intra prediction of the decoded luminance block.

Abstract: An intra prediction device performing intra prediction on a luminance block and a chrominance block includes: a chrominance candidate specifier configured to specify a mode number of an intra prediction mode applied to the luminance block corresponding to the chrominance block as one of candidates for an intra prediction mode to be applied to the chrominance block; and a chrominance prediction mode converter configured to convert the mode number before conversion specified by the chrominance candidate specifier using a conversion table and output a mode number after conversion. In the conversion table, for directional prediction, a given number of mode numbers in ascending order of the mode number among the mode numbers before conversion are associated with a given number of mode numbers in descending order of the mode number among the mode numbers after conversion.

Abstract: An image encoding device (1) includes a motion compensation predictor (109) configured to generate a prediction image corresponding to a target image by performing motion compensation prediction using a plurality of reference images, and an evaluator (111) configured to evaluate prediction accuracy of the prediction image for each image portion including one or more pixels by calculating a degree of similarity between the plurality of reference images for each image portion.

Abstract: A prediction image correcting device comprises a predictor (108) configured to predict a target image block obtained by dividing a present image frame by using a plurality of reference images to generate a prediction image corresponding to the target image block a prediction accuracy evaluator (109) configured to evaluate prediction accuracy of the prediction image based on a degree of similarity between the plurality of reference images used for generating the prediction image and a corrector (110) configured to perform correction processing on the prediction image by using a decoded neighboring block adjacent to the target image block, wherein the corrector is configured to control the correction processing based at least on an evaluation result of the prediction accuracy evaluator.

Abstract: An image encoding device (1) according to a first feature encodes blocks obtained by dividing an original image of a frame included in a video. The image encoding device (1) includes a code amount allocator (180) configured to allocate a code amount to each of a plurality of intra prediction modes defined in advance, a mode selector (171) configured to select an intra prediction mode to be applied to a target block of intra prediction from among the plurality of intra prediction modes, and an encoder (130) configured to encode identification information indicating the selected intra prediction mode in accordance with the allocated code amount. The code amount allocator (180) calculates a feature amount of a plurality of reference pixels adjacent to the target block and changes a manner of allocation of code amounts to the plurality of intra prediction modes based on the calculated feature amount.

Abstract: A deblocking filter device according to a first feature includes: a deblocking filter configured to perform a filter process on a boundary between a first reconstructed block and a second reconstructed block adjacent to the first reconstructed block; and a filter controller configured to control boundary filtering strength of the deblocking filter based on whether or not at least one of the first reconstructed block and the second reconstructed block is encoded using JCCR (Joint coding of chroma residual) in which one joint prediction residual is generated from prediction residuals of a Cb chrominance component and a Cr chrominance component.

Abstract: An encoding device encodes each encoding-target block.

Abstract: A deblocking filter control device that controls a deblocking filter process performed on a decoded image includes: a parameter deriver configured to derive a parameter value that controls a filter strength in the deblocking filter process; and a parameter transformer configured to output a transformed parameter value by transforming the parameter value based on an input bit depth that is a bit depth of the video signal, wherein when the input bit depth is smaller than a predetermined bit depth, the parameter transformer is configured to output the transformed parameter value by adding an offset value to the parameter value and making a bit shift of a result of the addition, and the parameter transformer is configured to change the offset value based on the input bit depth.

Abstract: A method includes: decoding a bitstream and thereby outputting a transform coefficients for each color component of the block, a first flag indicating for each color component whether the block includes a non-zero transform coefficient, and a second flag indicating whether the block has been encoded using a color space transform that transforming a color space of a prediction residual from a color space of the original image to another color space; performing a color space inverse transform for the prediction residual restored from the transform coefficients, when the second flag indicates that the block has been encoded using the color space transform; and determining whether to perform chroma residual scaling for the prediction residual of the chrominance component, based on the first flag of a chrominance component and the second flag, the chroma residual scaling that performs scaling based on a luminance component corresponding to the chrominance component.

Abstract: The encoding device includes: a predictor configured to generate, for each component, a prediction block corresponding to an encoding-target block; a residual generator configured to generate, for each component, a prediction residual representing a difference between the encoding-target block and the prediction block; a mode selector configured to select one mode either an individual encoding mode performing a transform process and a quantization process on a prediction residual of the first component and a prediction residual of the second component for each single component, or a joint encoding mode performing a transform process and a quantization process on a joint prediction residual generated from the prediction residual of the first component and the prediction residual of the second component; a quantization controller configured to determine a quantization matrix to be applied in the quantization process based on the mode selected by the mode selector.

Abstract: An encoding device encodes each encoding-target block.

Abstract: An encoding device includes: a quantizer configured to perform a quantization process; a loop filter configured to perform an adaptive loop filter process; and an entropy encoder configured to output a bit stream including an adaptive parameter set. The adaptive parameter set includes encoding tool type information indicating which parameter of parameter candidates including one of a scaling list parameter including a parameter of a scaling list that controls the quantization process and an adaptive loop filter parameter including a parameter of a filter coefficient used in the adaptive loop filter process is included in the adaptive parameter set, and a chrominance parameter present flag indicating whether or not a parameter for a chrominance signal is present in the adaptive parameter set, and the chrominance parameter present flag is applied in common to the scaling list parameter and the adaptive loop filter parameter.

Abstract: An image encoding device (1) includes the cross-component intra predictor (171a) generates a predicted chroma block through cross-component intra prediction in which a chroma block to be encoded is predicted by referring to, as the neighbouring decoded pixels adjacent to the chroma block, decoded luminance pixels and decoded chroma pixels, a candidate generator (181) configured to generate candidates for an orthogonal transform type to be applied to orthogonal transform processing on prediction residuals that represent errors between the predicted chroma block and the chroma block; and a transformer (121) configured to perform the orthogonal transform processing on the chroma prediction residuals by using an orthogonal transform type selected from among the candidates generated by the candidate generator (181).

Abstract: An encoding device that performs encoding on each of blocks obtained by dividing an image includes: a weighted bi-predictor 181a configured to generate a prediction block of an encoding-target block by weighted-averaging a plurality of reference images using weighted coefficients selected from a weighted coefficient set including a plurality of weighted coefficients; and a filter controller 161 configured to control deblocking filter based on the weighted coefficients applied by the weighted bi-predictor 181a to each of the two blocks adjacent blocks.

Abstract: An encoding device 1 includes: a merge predictor 181a configured to generate area prediction images using motion vectors of a plurality of divided areas obtained by dividing an encoding-target block and merge areas at boundaries of a plurality of the generated area prediction images through weighted averaging to generate a prediction block of the encoding-target block: and a filter controller 161 configured to control the deblocking filter based on a position of a merged area merged by the merge predictor 181a through the weighted averaging.

Abstract: An image encoding device encodes a block-based target image. The image encoding device comprises, in a transform skip mode in which orthogonal transform processing of the target image is skipped, a motion compensation predictor configured to generate a prediction image corresponding to the target image by performing motion compensation prediction using a plurality of reference images, an evaluator configured to evaluate a degree of similarity between the plurality of reference images on a pixel-by-pixel basis, a subtractor configured to calculate prediction residuals each indicating a difference between the target image and the prediction image on a pixel-by-pixel basis, a rearranger configured to rearrange the prediction residuals based on a result of evaluation by the evaluator and an encoder configured to encode the prediction residuals rearranged by the rearranger.