Abstract: An image encoding device include a predicting unit for adaptively determining the size of each motion prediction unit block according to color component signals, and for dividing each motion prediction unit block into motion, vector allocation regions to search for a motion vector, and a variable length encoding unit for, when a motion vector is allocated to the whole of each motion prediction unit block, performing encoding in mc_skip mode if the motion vector is equal to an estimated vector and a prediction error signal does not exist, and for, when each motion vector allocation region has a size equal to or larger than a predetermined size and a motion vector is allocated to the whole of each motion vector allocation region, performing encoding in sub_mc_skip mode if the motion vector is equal to an estimated vector and a prediction error signal does not exist.

Abstract: An image encoding device include a predicting unit for adaptively determining the size of each motion prediction unit block according to color component signals, and for dividing each motion prediction unit block into motion, vector allocation regions to search for a motion vector, and a variable length encoding unit for, when a motion vector is allocated to the whole of each motion prediction unit block, performing encoding in mc_skip mode if the motion vector is equal to an estimated vector and a prediction error signal does not exist, and for, when each motion vector allocation region has a size equal to or larger than a predetermined size and a motion vector is allocated to the whole of each motion vector allocation region, performing encoding in sub_mc_skip mode if the motion vector is equal to an estimated vector and a prediction error signal does not exist.

Abstract: In a decoder, a desired image is estimated by first retrieving coding modes from an encoded side information image. For each bitplane in the encoded side information image, syndrome bits or parity bits are decoded to obtain an estimated bitplane of quantized transform coefficients of the desired image. A quantization and a transform are applied to a prediction residual obtained using the coding modes, wherein the decoding uses the quantized transform coefficients of the encoded side information image, and is based on previously decoded bitplanes in a causal neighborhood. The estimated bitplanes of quantized transform coefficients of the desired image are combined to produce combined bitplanes. Then, an inverse quantization, an inverse transform and a prediction based on the coding modes are applied to the combined bitplanes to recover the estimate of the desired image.

Abstract: An image decoding device and an image decoding method are disclosed. The decoding device includes: a variable length decoder to variable-length-decode an inputted encoded bit stream to obtain a parameter for prediction signal generation, a compressed difference image, and filters; and a filtering processor to carry out a filtering process on a decoded image acquired by adding a prediction image and a difference image, wherein the prediction image is generated by using the parameter for prediction signal generation, and the difference image is acquired by decoding the compressed difference image, wherein the variable length decoder variable-length-decodes class identification information for a block in the decoded image, and wherein the filtering processor refers to the class identification information for the block to determine a class for the block, and carries out a filtering process on the block based on the determined class and the filters.

Abstract: Disclosed is an image encoding device which is constructed in such a way as to include an encoding mode determining unit 4 for evaluating the degree of efficiency of encoding of a difference image A which is the difference between an image of a macroblock to be encoded, and a prediction image A generated by a motion-compensated prediction unit 2 in a motion prediction mode A, and also evaluating the degree of efficiency of encoding of a difference image B which is the difference between the image of the macroblock to be encoded, and a prediction image B generated by the motion-compensated prediction unit 2 in a motion prediction mode B, and for selecting a difference image having a higher degree of encoding efficiency.

Abstract: A loop filter unit 11 carries out a class classification of a local decoded image generated by an adding unit 9 into one class for each coding block having a largest size determined by an encoding controlling unit 2 and also designs a filter that compensates for a distortion piggybacked for each local decoded image belonging to each class, and also carries out a filtering process on the above-mentioned local decoded image by using the filter. A variable length encoding unit 13 encodes, as filter parameters, the filter designed by the loop filter unit 11 and used for the local decoded image belonging to each class, and a class number of each largest coding block.

Abstract: An image encoding device include a predicting unit for adaptively determining the size of each motion prediction unit block according to color component signals, and for dividing each motion prediction unit block into motion vector allocation regions to search for a motion vector, and a variable length encoding unit for, when a motion vector is allocated to the whole of each motion prediction unit block, performing encoding in mc_skip mode if the motion vector is equal to an estimated vector and a prediction error signal 5 does not exist, and for, when each motion vector allocation region has a size equal to or larger than a predetermined size and a motion vector is allocated to the whole of each motion vector allocation region, performing encoding in sub_mc_skip mode if the motion vector is equal to an estimated vector and a prediction error signal does not exist.

Abstract: An intra-scene and inter-scene adaptive coding unit 6 converts an MPEG-2 video bit stream into a slave stream by using both coded data which is included in the coded data about scene video units in a master stream recorded in a data recording unit 2 and for which alternative coded data to be used for prediction reference has not been retrieved by an inter-scene prediction determining unit 5, and coded data retrieved by the inter-scene prediction determining unit 5 for the prediction reference.

Abstract: A tile partitioning unit 1 that partitions an inputted image into tiles each of which is a rectangular region having a specified size and outputs the tiles is disposed, and a block partitioning unit 10 of a partition video encoding unit 3 partitions a tile outputted from the tile partitioning unit 1 into coding blocks each having a predetermined size and also partitions each of the coding blocks hierarchically until the number of hierarchical layers reaches an upper limit on the number of hierarchical layers which is determined by an encoding controlling unit 2.

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 image decoding device method for obtaining image signals by decoding compressed data of digital moving image signals in a 4:4:4 format is disclosed. An identification signal is decoded, the identification signal indicating whether three color component signals have been encoded in a common encoding mode or in independent encoding modes. The common encoding mode corresponds to a process of encoding the three color component signals of one frame by a common macroblock type information and the independent encoding mode corresponds to a process of encoding the three color component signals of one frame by an individual independent macroblock type information. The three color component signals are decoded in a common encoding mode or in independent encoding modes according to the identification signal.

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: There are provided an encoding device, a decoding device, an encoding method, and a decoding method that enhance optimality in a case of encoding moving image signals having no sample ratio distinction between color components such as a 4:4:4 format. In a case of conducting compression encoding by inputting digital moving image signals of the 4:4:4 format, there are prepared a first encoding process of encoding three color component signals of the input moving image signals in a common encoding mode, and a second encoding process of encoding the three color component signals of the input moving image signals in respective independent encoding modes. The encoding process is executed by selecting any one of the first encoding process and the second encoding process, and the compression data contains an identification signal for specifying which process is selected.

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: Disclosed is an image decoding method including a step of variable-length-decoding coded data multiplexed into a bitstream to acquire compressed data associated with a coding block, a reference image restriction flag indicating whether or not to restrict a significant reference image area which is an area on a reference image which can be used for the motion-compensated prediction, and motion information and a motion-compensated prediction step of carrying out a motion-compensated prediction process on the coding block on the basis of the motion information to generate a prediction image, in which the motion-compensated prediction step includes a step of when the prediction image includes a pixel located outside the significant reference image area, carrying out a predetermined extending process to generate the prediction image on the basis of the reference image restriction flag by using the motion information.

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 refers to a table for filter selection to select 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 the prediction image by using the filter. As a result, prediction errors locally occurring can be reduced, and the image quality can be improved.

Abstract: The image encoding apparatus of one embodiment of the present invention comprises a coding mode determination unit, a prediction image generation unit, a storage unit, and an encoding unit. The coding mode determination unit determines a coding mode relating to which of the first image prediction processing or second image prediction processing is used for generating prediction image of a partial area of input images. The prediction image generation unit extracts the prediction assist information by the first image prediction processing and generates a prediction image based on the prediction assist information. The storage unit stores the reproduced image that is based on the prediction image. The encoding unit generates a bit stream comprising data obtained by encoding the coding mode information and prediction assist information.

Abstract: When a coding mode selected by an encoding controlling part 1 is an intra prediction mode, an intra prediction part 4 carries out an intra-frame prediction process using pixels adjacent to a partition Pin which is generated through a division by a block dividing part 2 or pixels adjacent to a higher layer partition to which the partition Pin belongs to generate a prediction image (Pin).

Abstract: An image encoder including: a predicted-image generating unit that generates a predicted image in accordance with a plurality of prediction modes indicating predicted-image generating methods; a prediction-mode judging unit that evaluates prediction efficiency of a predicted image outputted from the predicted-image generating unit to judge a predetermined prediction mode; and an encoding unit that subjects an output of the prediction-mode judging unit to variable-length encoding.

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.