Abstract: A moving-picture encoder performs efficient encoding by selecting prescribed encoding on the basis of a decoded block of a frame which includes a block to be encoded, and performing predictive encoding of the block to be encoded by using the selected encoding.

Abstract: There are disclosed an image encoding apparatus comprising an input unit for inputting image data, a calculation unit for calculating an entropy of the image data inputted by the input unit, a control unit for controlling a quantization step in accordance with the entropy calculated by the calculation unit, and an encoding unit for encoding the image data inputted by the input unit in accordance with the quantization step controlled by the control unit, an image encoding apparatus comprising an input unit for inputting image data, a calculation unit for calculating an entropy of the image data inputted by the input unit, a transform unit for orthogonally transforming the image data inputted by the input unit, a mask unit for masking transform coefficients of the image data transformed by the transform unit, and an encoding unit for encoding the image data masked by the mask unit.

Abstract: A coding apparatus is arranged to eliminate predetermined image data from input image data and code the input image data from which the predetermined image data is eliminated. A decoding apparatus is arranged to decode the coded image data from which the predetermined image data is eliminated and combine desired image data with the decoded image data.

Abstract: An image processing apparatus entropy encodes plural encoding target data by using a first entropy encoding table to provide respective data amounts of plural encoded data and compares the data amounts of plural encoded data with each other. One of the plural encoding target data is selected according to the result of the comparison and a second entropy encoding table is produced according to the content of the selected encoding target data. The apparatus then entropy encodes the selected encoding target data utilizing the second entropy encoding table.

Abstract: An encoding error by the encoding and the decoding of an image is controlled within a predetermined range by an image processing apparatus which includes an input unit for inputting image data, a prediction unit for predicting pixel values indicated by the image data, a generation unit for generating pixel values derived by converting the pixel values of the image data within a range of .+-.e based on the prediction result by said prediction unit and an encoding unit for encoding parameters relating to the pixel values generated by said generation unit based on the prediction result by said prediction unit.

Abstract: An amount of data coded in the past is detected at a prescribed period. Criteria for deciding whether a pixel block of interest is to be coded by processing for motion-compensated coding of interframe difference, processing for coding of interframe difference without motion compensation or processing for intraframe coding are adjusted based upon the amount of code detected.

Abstract: An image processing apparatus includes an input unit for inputting image data having undergone orthogonal transformation, a generation unit for generating interframe difference image data, of adjacent frames with respect to the image data input by the input unit, using orthogonal transform coefficients, and an encoding unit for encoding the image data output from the generation unit. An image processing apparatus includes an input unit for inputting encoded data obtained by performing block encoding of interframe difference data using orthogonal transformation, a decoding unit for decoding the encoded data input by the input unit into orthogonal transform coefficient difference data, and an addition unit for adding the orthogonal transform coefficient data of a block different from a processed block to the difference data decoded by the decoding unit.

Abstract: An image processor includes a forming unit which measures a feature of a first image and a feature of a second image for a plurality of pixels other than an encode objective pixel, thereby forming a first measurement result and a second measurement result, respectively. An encoder determines an encoding method of the encode objective pixel on the basis of a plurality of the first measurement results and a plurality of the second measurement results, and encodes by using the determined encoding method.

Abstract: At the encoding side, a sum of code lengths of a block is calculated and stored in a memory for each of block lines (stripes); and at the decoding side, when decoding of one block is completed, a head address of a code in the next block is calculated utilizing a sum of an amount of codes utilized for the decoding operation and code lengths for each of the stripes. The rotation process of an image utilizing encoded data is performed in accordance with the head address. Further, at the encoding side, colors of pixels in a predetermined block is determined, and encoding operation is performed block by block for only those blocks including pixels of different colors. At the decoding side, an address of block data for sequentially constructing a rotated image is controlled to decode the pixels in the block, and finally the rotation process is performed on the pixels in the block in accordance with the color of the pixels.

Abstract: An object of the present invention is to data compress a binary image which includes a pseudo expressed halftone image effectively. To attain this object, an image processing apparatus of the present invention comprises region division means for dividing an input binary image data into a region of a pseudo expressed halftone image portion and a region of another portion, first encoding means for generating multi-value image data from binary image data of said pseudo expressed halftone image portion and encoding the obtained multi-value image data, second encoding means for encoding at least a part of the binary image data from a portion other than the pseudo expressed halftone image portion.

Abstract: Image coding method and apparatus for improving image quality by controlling amount of encoded image data in variable-length coding. The image encoding apparatus comprising: input unit for inputting image data for each block having a first size; encoding unit for encoding the image data for each block and generating encoded image data; and controlling unit for controlling an encoding parameter for each block in accordance with amount of the encoded image data, wherein controlling unit controls the encoding parameter further in accordance with the position of the block to be encoded.

Abstract: An image processing apparatus comprising binarization means for converting a multi-level color signal into binary form, removal means for removing edge component from the multi-level color signal, based on a binary color signal from said binarization means, and encoder means for encoding the binary color signal from said binarization means and the multi-level color signal having edge component removed with said removal means.

Abstract: In compressing an image in units of blocks, the image is compressed in accordance with the size of a redundant portion of the image to increase the compression factor of the image data. An image compression apparatus for encoding an image in units of blocks includes a size discrimination unit for discriminating a block image size suitable for encoding and compressing a predetermined image area, a generation unit for dividing the image area to generate a plurality of block images having different sizes on the basis of the discrimination result of the size discrimination unit, and a compression unit for compressing each block image data representing a block image and generated from the generation unit, on the basis of the size of the block image data.

Abstract: A color image encoding method to encode a color image signal expressed by a plural number of color component signals, wherein the plural number of color component signals of a pixel of interest are input serially, encoding conditions are serially determined in relation to each color component signal of the pixel of interest input serially, and each color component signal of the pixel of interest input serially is encoded according to the encoding conditions determined serially.

Abstract: A movement vector detecting apparatus for detecting a movement vector of an object between frames which are close to each other on a block unit basis is provided. A first mode to detect the movement vector by using color components and a second mode to detect the movement vector by using a luminance component are switched in accordance with chromaticity statistics of an input block, thereby detecting the movement vector.

Abstract: An encoding apparatus wherein a difference between an input signal to be encoded and a prediction value is quantized, the quantized signal is generated, the quantized differential signal is inversely quantized, the sum of the inversely quantized reproduction differential signal and the prediction value is stored, the stored signal is read out on the basis of an address signal regarding the input signal, the read-out signal and the input signal are received as inputs and the prediction value is obtained. When the prediction value is derived, an evaluation function to obtain the prediction value is determined in accordance with chromaticity statistics of the input signal.

Abstract: When image data coded by a DCT coding method in a predetermined block size is to be decoded, an image processing apparatus extracts necessary DCT coefficients of a block on the basis of an enlargement/reduction ratio determined in advance, then decodes the extracted DCT coefficients. Thereby it is possible to produce a reduced image at high speed without using a memory of high capacity.

Abstract: An image processing apparatus in which a multi-level color signal is input and converted into a binary color signal. An edge component is removed from the multi-level color signal based on the binary color signal and the binary color signal and the multi-level color signal of which the edge component is removed are encoded.

Abstract: The present invention provides a motion vector detecting device or method by which dependable motion vectors are detected. The device, according to one aspect of the invention, searches for a similar block in a previous image to a subject block in both a first area expanding from a corresponding position to the subject block and a second area expanding from a position indicated by a predictive vector and detecting a motion vector according to a result of the searching. Because there is a fair possibility of occurring the similar block in both the first and second areas.

Abstract: A quantized vector decoder, a method of making the code book therefor, a system for transferring quantized vector, an image processing apparatus utilizing the vector quantization, and a vector quantizer are disclosed, the quantized vector being arranged to decode codes, which have been formed by vector-quantizing vectors formed of collecting a plurality of data items correlating to one another into output vectors, the decoder comprising: an input device for receiving the codes; a code book for previously storing the output vectors of the vector-quantized codes, each of the output vectors in the code book being constituted by a first output-vector component portion and a second output vector component portion; a retrieval device for retrieving the output vectors in the code book depending upon the correspondence between an input code and the first output-vector component portion; and an output device for transmitting the retrieved output vectors in the form of a combination of their first and second output vec