Abstract: An image processing device for compressing image data using conversion to spatial frequency components may include a dividing section that divides the image data into a plurality of pixel blocks and computes spatial frequency components of each pixel block; a segmenting section that computes an intensity of predetermined high frequency components from information of the spatial frequency components and segments the image data into a first plane formed by including a pixel block having an intensity which is less than a predetermined threshold value and into a second plane formed by including a pixel block having an intensity which is equal to or greater than the threshold value; a compression section that executes compression for the first plane image data by applying quantization and entropy coding using the spatial frequency components information; and a run length compression section that executes run length compression of the second plane image data.

Abstract: An image processing apparatus includes an image element allocation unit that allocates image elements included in input image data to any of plural mutually-different coding processings, in accordance with a allocation reference, a coding unit that encodes, by the respective coding processings, the image elements allocated to the respective coding processings by the image element allocation unit, and a reference change unit that changes the allocation reference applied by the image element allocation unit.

Abstract: An image processing device for compressing image data using conversion to spatial frequency components may include a dividing section that divides the image data into a plurality of pixel blocks and computes spatial frequency components of each pixel block; a segmenting section that computes an intensity of predetermined high frequency components from information of the spatial frequency components and segments the image data into a first plane formed by including a pixel block having an intensity which is less than a predetermined threshold value and into a second plane formed by including a pixel block having an intensity which is equal to or greater than the threshold value; a compression section that executes compression for the first plane image data by applying quantization and entropy coding using the spatial frequency components information; and a run length compression section that executes run length compression of the second plane image data.

Abstract: A coding device includes a first coding unit that uses a Markov model coding system to code noticed data as a coding object, a second coding unit that uses a coding system different from the Markov model coding system to code the noticed data, and a selection unit that selects, as a coding unit to be applied, one of the first coding unit and the second coding unit based on the noticed data.

Abstract: A coding apparatus includes a color space conversion unit that converts input image data into image data which is represented in another color space, a gradation changing unit that changes gradation of the input image data, based on the converted image data, and a predictive coding unit that performs predictive coding on the image data subjected to the gradation change.

Abstract: An image processing apparatus disclosed herein includes an extracting unit that extracts a pixel cluster of a predetermined size from input image data, and a coding unit that codes the input image data, based on correlation between pixel clusters extracted by the extracting unit.

Abstract: Conversion between different codes can be implemented at high speed by a small device. A code input unit inputs a code. A compatible information reference unit refers to compatible information of each compressed symbol before and after code conversion, which then sends out compatible information data to a compressed symbol conversion unit. The compressed symbol conversion unit converts each of the compressed symbols in the input code data to a form adapted to a code to be converted based on the compatible information data, which then sends out converted code data to a converted code output unit.

Abstract: An encoding device to encode data of a motion picture made of a plurality of frame images, the encoding device includes a reference information generating unit, based on image data of a frame image of notice to be encoded, to generate reference information with respect to another frame image different from the frame image of notice, and a code generating unit to generate code data of the reference information generated by the reference information generating unit as code data of at least a portion of the frame image of notice.

Abstract: An encoding device to encode an object image to be encoded includes a reference information generating unit that generates reference information with respect to a key image different from the object image, and a code generating unit that generates code data of the reference information generated by the reference information generating unit as code data of at least a portion of the object image.

Abstract: The image input from the image inputting portion 10 are DCT-converted by the DCT portion 20, then the converted result is quantized by the quantizing portion 40, then the quantized result is entropy-coded by the entropy coding portion 50, and then the coded output is output. The quantization table calculating portion 30 holds respective reference quantizing steps for the reference resolution, then receives the resolution data of the input image, then calculates respective quantizing steps based on (quantizing step)=(reference quantizing step)/(reference resolution)×(resolution of the input image) so as to fit to the input image, and then prepares the quantization table.

Abstract: A system and method are provided for realizing high speed and high efficiency in compression of image data having periodicity. The present invention includes the following: an image input unit to input image signal; a first predictive converter which converts relation between the pixel value of a target pixel in the image signal inputted through the image input part and that of another pixel into a first prediction value; a first encoder which generates intermediate data by encoding the first prediction value output from the first predictive converter; a second predictive converter which converts relation between a target symbol among symbols making up the intermediate data generated by the first encoder and another symbol into a second prediction value; and a second encoder which generates an encoded signal by encoding the second prediction value output from the second predictive converter.

Abstract: Filtering for enhancing the reversible compression rate is performed for image data as preprocessing of compression processing. For image processing after the filtering, repeating of compression and decompression according to the reversible compression technique corresponding to the filtering is allowed. As the filtering and reversible compression processing are performed, a sufficient compression ratio is provided and accumulation of image quality degradation by repeating compression and decompression is prevented.

Abstract: An input image is subjected to transform by a DCT transforming unit 20. A coefficient analyzing unit 30 compares a predetermined coefficient and coefficient data 120, and obtains low-frequency image data 150 of the input image by a high-frequency coefficient masking unit 50 and an inverse DCT unit 60 on the basis of a result of that comparison. A pixel subsampling unit 70 receives this low-frequency image data 150, and generates a subsampled image on the basis of the aforementioned result of comparison. The subsampled image and coefficient information are transmitted to a decoding side. A decoding apparatus decodes an image on the basis of the subsampled image and the coefficient information.

Abstract: A data encoding device and a data decoding device. A data encoding device refers to first and second encoding tables to search for a code word correlated with encoding data. One of the code words is selected according to predetermined criteria. When the selected code word requires additional information, additional information is generated. A data decoding device refers to the first and second encoding tables and retrieves a data element from at least one of the tables. When additional information is available, original data is calculated based on the data element and the additional information. When additional information is not available, the retrieved data element is output without modification as original data.

Abstract: To provide an image coding apparatus that can generate a code that can be decoded by a general decoding apparatus while attaining a high coding speed. As a result of processing in a plurality of prediction units 21, a control unit 11 generates a predicted pixel value for a pixel of interest based on a pixel value of a predicting pixel located at a distance from the pixel of interest, the distance being predetermined for each pixel value prediction unit 21, counts, as a run-length for each pixel value prediction unit 21, the number of times that the pixel value of the pixel of interest successively correspond with the predicted pixel value, selects any of pixel value prediction units related to a run-length of one pixel or more, and outputs a code by referring to a predetermined code table with respect to a distance between the pixel of interest and the predicting pixel for the selected pixel value prediction unit 21 and the run-length thereof.

Abstract: There is provided an image processing device that can sufficiently improve compression efficiency with a slight processing load.

Abstract: An input image is subjected to transform by a DCT transforming unit 20. A coefficient analyzing unit 30 compares a predetermined coefficient and coefficient data 120, and obtains low-frequency image data 150 of the input image by a high-frequency coefficient masking unit 50 and an inverse DCT unit 60 on the basis of a result of that comparison. A pixel subsampling unit 70 receives this low-frequency image data 150, and generates a subsampled image on the basis of the aforementioned result of comparison. The subsampled image and coefficient information are transmitted to a decoding side. A decoding apparatus decodes an image on the basis of the subsampled image and the coefficient information.

Abstract: To realize image coding/decoding device that can compress an input multivalued image with high compression efficiency, the following measures are taken. First and second predictors predict the value of a target pixel based upon image data according to respective predetermined methods and respectively generate predicted value data. A run counter compares the image data and the predicted value data and if prediction hits and run continues to a pixel immediately before a count value of the run of the corresponding predictor is incremented by one. If there is no predictor the prediction of which hits and the runs of which continued to a pixel immediately before, the runs are sent to a selector together with the identification number of the predictor as run data. The selector selectively outputs a run value and an identification number or prediction error data from a prediction error calculator and outputs after the selector encodes it (them).

Abstract: A data encoding device and a data decoding device. A data encoding device refers to first and second encoding tables to search for a code word correlated with encoding data. One of the code words is selected according to predetermined criteria. When the selected code word requires additional information, additional information is generated. A data decoding device refers to the first and second encoding tables and retrieves a data element from at least one of the tables. When additional information is available, original data is calculated based on the data element and the additional information. When additional information is not available, the retrieved data element is output without modification as original data.

Abstract: An image processing device that executes high speed overwriting of an input image with one or more partial images. A processing prediction unit judges whether overwriting is completed on all the partial images held in a small area buffer. If overwriting is completed, the overwritten partial image is compressed by an encoding unit, and the coded image is stored in a compact page memory. If overwriting is not completed, the uncompressed partial image is stored in the compact page memory. The uncompressed partial image is read from the compact page memory and is fed back to the overwriting unit through an output switch unit. The coded image stored in the compact page memory is sent to a decoding unit through the output switch unit, and is decoded to be outputted as an output image.