Abstract: When carrying out an intra-frame prediction process to generate an intra prediction image by using an already-encoded image signal in a frame, an intra prediction part 4 selects a filter from one or more filters which are prepared in advance according to the states of various parameters associated with the encoding of a target block to be filtered, and carries out a filtering process on a prediction image by using the filter. As a result, prediction errors which occur locally can be reduced, and the image quality can be improved.

Abstract: When carrying out an intra-frame prediction process to generate an intra prediction image by using an already-encoded image signal in a frame, an intra prediction part 4 selects a filter from one or more filters which are prepared in advance according to the states of various parameters associated with the encoding of a target block to be filtered, and carries out a filtering process on a prediction image by using the filter. As a result, prediction errors which occur locally can be reduced, and the image quality can be improved.

Abstract: When an intra prediction parameter indicates a horizontal prediction process, an intra prediction unit adds a value proportional to a change in a horizontal direction of the luminance values of pixels adjacent to the top of each block, which is a unit for prediction process of a coding block, to the luminance value of a pixel adjacent to the left of the block to set a result of the addition as a predicted value of a prediction image, whereas when the intra prediction parameter indicates a vertical prediction process, the intra prediction unit adds a value proportional to a change in a vertical direction of the luminance values of pixels adjacent to the left of the block to the luminance value of the pixel adjacent to the top of the block to set the result of the addition as a predicted value of the prediction image.

Abstract: When carrying out an intra-frame prediction process to generate an intra prediction image by using an already-encoded image signal in a frame, an intra prediction part 4 selects a filter from one or more filters which are prepared in advance according to the states of various parameters associated with the encoding of a target block to be filtered, and carries out a filtering process on a prediction image by using the filter. As a result, prediction errors which occur locally can be reduced, and the image quality can be improved.

Abstract: When carrying out an average prediction, an intra predictor carries out a filtering process on target pixels of the intra prediction located at an upper end and a left end of the block, the filtering process using an intermediate prediction value, which is an average value of adjacent pixels of the block, and at least one adjacent pixel of the target pixel. The intra predictor also sets a filter coefficient to ¾, associated with the intermediate prediction value for a target pixel at the left end of the block other than the target pixel at an upper left corner of the block, and sets a filter coefficient to ¼, associated with the adjacent pixel adjacent to the left side of the target pixel at the left end of the block. As a result, prediction errors locally occurring can be reduced, and the image quality can be improved.

Abstract: When an intra prediction parameter indicates a horizontal prediction process, an intra prediction unit adds a value proportional to a change in a horizontal direction of the luminance values of pixels adjacent to the top of each block, which is a unit for prediction process of a coding block, to the luminance value of a pixel adjacent to the left of the block to set a result of the addition as a predicted value of a prediction image, whereas when the intra prediction parameter indicates a vertical prediction process, the intra prediction unit adds a value proportional to a change in a vertical direction of the luminance values of pixels adjacent to the left of the block to the luminance value of the pixel adjacent to the top of the block to set the result of the addition as a predicted value of the prediction image.

Abstract: An encoding controlling unit 3 selects one transformation block size which provides an optimal degree of encoding efficiency from a set of transformation block sizes which are determined in accordance with an encoding mode 7, and includes the transformation block size selected thereby in optimal compression parameters 20a to notify the transformation block size to a transformation/quantization unit 19, and the transformation/quantization unit 19 divides an optimal prediction differential signal 13a into blocks having the transformation block size included in the optimal compression parameters 20a, and carries out a transformation and quantization process on each of the blocks to generate compressed data 21.

Abstract: An encoding controlling unit 3 selects one transformation block size which provides an optimal degree of encoding efficiency from a set of transformation block sizes which are determined in accordance with an encoding mode 7, and includes the transformation block size selected thereby in optimal compression parameters 20a to notify the transformation block size to a transformation/quantization unit 19, and the transformation/quantization unit 19 divides an optimal prediction differential signal 13a into blocks having the transformation block size included in the optimal compression parameters 20a, and carries out a transformation and quantization process on each of the blocks to generate compressed data 21.

Abstract: A variable length encoding unit 13 variable-length-encodes an index indicating a classification method of carrying out a class classification on each coding block having a largest size, the classification method being determined by a loop filter unit 11, and also variable-length-encodes a parameter about an offset value for each class determined for each coding block having the largest size on the basis of a binarization process using a truncated unary code.

Abstract: A parallel processing starting unit 3 that partitions an inputted image into tiles each having a predetermined size, and distributes tiles obtained through the partitioning, and N tile encoding units 5-1 to 5-N each of that carries out a prediction difference encoding process on a tile distributed thereto by the parallel processing starting unit 3 to generate a local decoded image are disposed, and each of N tile loop filter units 7-1 to 7-N determines a filter per tile suitable for a filtering process on the local decoded image generated by the corresponding one of the tile encoding units 5-1 to 5-N, and carries out the filtering process on the local decoded image by using the filter.

Abstract: A parallel processing starting unit 3 that partitions an inputted image into tiles each having a predetermined size, and distributes tiles obtained through the partitioning, and N tile encoding units 5-1 to 5-N each of that carries out a prediction difference encoding process on a tile distributed thereto by the parallel processing starting unit 3 to generate a local decoded image are disposed, and each of N tile loop filter units 7-1 to 7-N determines a filter per tile suitable for a filtering process on the local decoded image generated by the corresponding one of the tile encoding units 5-1 to 5-N, and carries out the filtering process on the local decoded image by using the filter.

Abstract: An encoding controlling unit 3 selects one transformation block size which provides an optimal degree of encoding efficiency from a set of transformation block sizes which are determined in accordance with an encoding mode 7, and includes the transformation block size selected thereby in optimal compression parameters 20a to notify the transformation block size to a transformation/quantization unit 19, and the transformation/quantization unit 19 divides an optimal prediction differential signal 13a into blocks having the transformation block size included in the optimal compression parameters 20a, and carries out a transformation and quantization process on each of the blocks to generate compressed data 21.

Abstract: When removing a block distortion occurring in a local decoded image, a loop filtering part 11 of an image coding device carries out a filtering process on each of signal components (a luminance signal component and color difference signal components) after setting the intensity of a filter for removing the block distortion for each of the signal components according to a coding mode (an intra coding mode or an inter coding mode) selected by a coding controlling part 1.

Abstract: An encoding controlling unit 3 selects one transformation block size which provides an optimal degree of encoding efficiency from a set of transformation block sizes which are determined in accordance with an encoding mode 7, and includes the transformation block size selected thereby in optimal compression parameters 20a to notify the transformation block size to a transformation/quantization unit 19, and the transformation/quantization unit 19 divides an optimal prediction differential signal 13a into blocks having the transformation block size included in the optimal compression parameters 20a, and carries out a transformation and quantization process on each of the blocks to generate compressed data 21.

Abstract: An image decoding device and method that set up a first skip mode and second skip mode for each motion prediction and block and its motion vector allocation regions, respectively, allowing for expressing a hierarchy of skip modes when decoding a video signal having a specific format and can be adaptive to the characteristics of a temporal change of each color component signal.

Abstract: An image decoding device and method that set up a first skip mode and second skip mode for each motion prediction and block and its motion vector allocation regions, respectively, allowing for expressing a hierarchy of skip modes when decoding a video signal having a specific format and can be adaptive to the characteristics of a temporal change of each color component signal.

Abstract: An image decoding device and method that set up a first skip mode and second skip mode for each motion prediction and block and its motion vector allocation regions, respectively, allowing for expressing a hierarchy of skip modes when decoding a video signal having a specific format and can be adaptive to the characteristics of a temporal change of each color component signal.

Abstract: When removing a block distortion occurring in a local decoded image, a loop filtering part 11 of an image coding device carries out a filtering process on each of signal components (a luminance signal component and color difference signal components) after setting the intensity of a filter for removing the block distortion for each of the signal components according to a coding mode (an intra coding mode or an inter coding mode) selected by a coding controlling part 1.

Abstract: When an encoding mode corresponding to one of blocks to be encoded into which an image is divided by a block dividing part 2 is an inter encoding mode which is a direct mode, a motion-compensated prediction part 5 selects a motion vector suitable for generation of a prediction image from one or more selectable motion vectors and also carries out a motion-compensated prediction process on the block to be encoded to generate a prediction image by using the motion vector, and outputs index information showing the motion vector to a variable length encoding part 13, and the variable length encoding unit 13 variable-length-encodes the index information.

Abstract: When an encoding mode corresponding to one of blocks to be encoded into which an image is divided by a block dividing part 2 is an inter encoding mode which is a direct mode, a motion-compensated prediction part 5 selects a motion vector suitable for generation of a prediction image from one or more selectable motion vectors and also carries out a motion-compensated prediction process on the block to be encoded to generate a prediction image by using the motion vector, and outputs index information showing the motion vector to a variable length encoding part 13, and the variable length encoding unit 13 variable-length-encodes the index information.