Abstract: An encoding device comprises: a transformer/quantizer configured to perform a transform process and a quantization process on a residual signal that represents a difference between an encoding-target block and a prediction block obtained by predicting the encoding-target block; an inverse quantizer/inverse transformer configured to restore the residual signal by performing an inverse quantization process and an inverse transform process on transform coefficients obtained by the transformer/quantizer; a combiner configured to reconstruct the encoding-target block by combining the restored residual signal and the prediction block; a deblocking filter configured to perform a filter process on a boundary between two blocks including the reconstructed block and a block adjacent to the reconstructed block; and a filter controller configured to control the deblocking filter, based on a type of the transform process applied with respect to the two blocks.

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

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: 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: 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: 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: 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.

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

Abstract: An intra predictor (181) for performing intra prediction on each of blocks obtained by dividing an original image in the form of a frame, the intra predictor (181) includes; a linear model calculator (1811a) configured to calculate a linear model of the luminance component and the chroma component of the target block using decoded pixel values of the luminance component and decoded pixel values of the chroma component around the target block on which the intra prediction is performed; a chroma component predictor (1811b) configured to predict pixel values of the chroma component of the target block by applying the linear model calculated by the linear model calculator (1811a) to decoded pixel values of a luminance component of the target block; and a chroma component corrector (1812) configured to correct predicted pixel values of the chroma component obtained by the chroma component predictor (1811b) using decoded pixel values that were not used to calculate a linear model by the linear model calculator (181

Abstract: An encoding device comprises: a transformer/quantizer configured to perform a transform process and a quantization process on a residual signal that represents a difference between an encoding-target block and a prediction block obtained by predicting the encoding-target block; an inverse quantizer/inverse transformer configured to restore the residual signal by performing an inverse quantization process and an inverse transform process on transform coefficients obtained by the transformer/quantizer; a combiner configured to reconstruct the encoding-target block by combining the restored residual signal and the prediction block; a deblocking filter configured to perform a filter process on a boundary between two blocks including the reconstructed block and a block adjacent to the reconstructed block; and a filter controller configured to control the deblocking filter, based on a type of the transform process applied with respect to the two blocks.

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

Abstract: An image encoding device (1) encodes a block-based target image. The image encoding device (1) comprises: a predictor (109) configured to generate a prediction image corresponding to the target image by performing prediction using a plurality of reference images; an evaluator (111) configured to evaluate a degree of similarity between the plurality of reference images on a pixel-by-pixel basis; a calculator (101) configured to calculate a prediction residual indicating a pixel-based difference between the target image and the prediction image; a determiner (112) configured to determine a partial area, to which an orthogonal transform and quantization are to be applied, of the prediction residual based on a result of the evaluation by the evaluator; and a transformer/quantizer (102) configured to perform an orthogonal transform and quantization only for the partial area in the prediction residual.

Abstract: An encoding device (1) according to the present invention includes: an encoding processing order determiner (11) configured to determine encoding processing order of blocks to be encoded; an intra-prediction mode candidate generator (12) configured to generate intra-prediction mode candidates of the blocks to be encoded, based on the encoding processing order; an intra-prediction mode determiner (13) configured to determine intra-prediction modes to be applied to the blocks to be encoded from the intra-prediction mode candidates; an intra predictor (14) configured to perform intra-prediction processing on the blocks to be encoded, based on the determined encoding processing order and the intra-prediction modes; and an entropy encoder (15) configured to perform entropy encoding processing on the encoding processing order and the intra-prediction modes.

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 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) encodes a block-based target image. The image encoding device (1) comprises: a predictor (109) configured to generate a prediction image corresponding to the target image by performing prediction using a plurality of reference images; an evaluator (111) configured to evaluate a degree of similarity between the plurality of reference images on a pixel-by-pixel basis; a calculator (101) configured to calculate a prediction residual indicating a pixel-based difference between the target image and the prediction image; a determiner (112) configured to determine a partial area, to which an orthogonal transform and quantization are to be applied, of the prediction residual based on a result of the evaluation by the evaluator; and a transformer/quantizer (102) configured to perform an orthogonal transform and quantization only for the partial area in the prediction residual.

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

Abstract: An encoding device performing an encoding process in units of blocks into which images constituted by luminance signals and chrominance signals are divided includes: a predictor configured to predict a target chrominance block which is an encoding target block of the chrominance signals and generate a prediction chrominance block; a residual generator configured to generate a chrominance prediction residual indicating a difference between the target chrominance block and the prediction chrominance block; and a transformer configured to apply a transform process to the chrominance prediction residual and generate transform coefficients, wherein the transformer is configured to control, according to a signal format of the images, a transform type to be applied to the transform process.