Abstract: Provided is an image processing apparatus which includes a histogram generating unit that generates a histogram representing an appearance frequency distribution of a pixel value of an input image, and a quantization table generating unit that generates a quantization table including table information used to perform transform of a bit depth of the pixel value of the input image and table information used to allocate an effective pixel in which an appearance frequency in the histogram generated by the histogram generating unit is not zero to an index value after bit depth transform so that effective pixels are allocated to index values as equally as possible.

Abstract: There is provided an image processing apparatus including a zero class detecting unit that detects a zero class in which an appearance frequency of a pixel value is zero from among a plurality of classes into which pixel values of an image are classified according to pixel value magnitude, and a non-zero class converting unit that converts the zero class into a non-zero class in which the appearance frequency of the pixel value is one or more, without updating a total number of the classes, by updating a range of the zero class detected by the zero class detecting unit. The present disclosure can be applied to an image processing apparatus.

Abstract: There is provided an image processing device which transforms an image with a bit depth of N into an upper layer with a bit depth of M and a remaining lower layer, including a histogram unit that generates histogram indicating occurrence frequency of each pixel value of an image with a bit depth of N, a table unit that generates a table listing pixel values of which occurrence frequency in the histogram generated by the histogram unit is equal to or more than one, a reordering unit that reorders an arrangement of values in the histogram using the table generated by the table unit, an update unit that updates the table generated by the table unit and the histogram reordered by the reordering unit; and an index image unit that generates an index image with a bit depth of N using the updated table and the updated histogram.

Abstract: There is provided an image processing apparatus including: a first color transform unit carrying out a color transform on a combination of color components with high correlation out of a plurality of color components included in image data; and a second color transform unit carrying out a color transform on a combination of color components aside from the combination of color components subjected to the color transform by the first color transform unit out of the plurality of color components included in the image data.

Abstract: A master key (K2,2) inputted by an input unit is stored in a storage unit. A matrix generating unit generates key element matrices (M1-M3) with respect to each of split keys (eR2, eR1, eR3) obtained by a key dividing unit dividing the master key (K2,2). To each coordinate entry of the key element matrices (M1-M3), operation data that successively obtained by repeating a hash operation with a one-way hash function is assigned, so as to maintain hierarchical nature of scalability (L). A key generating unit generates partial keys (K1,1-K2,2) corresponding to respective hierarchies of the scalabilities (R, L), on the basis of the key element matrices (M1-M3). These partial keys (K1,1-K2,2) are outputted to a coding unit or a decoding unit by an output unit.

Abstract: There is provided an image processing apparatus which includes a division unit dividing an image into a plurality of images in a bit depth direction, and an encoding unit encoding respectively some or all of the plurality of images acquired by dividing the image in the bit depth direction by the division unit.

Abstract: A code block size comparison unit examines an inclusion relationship of code block size. A comparing target code block determination unit determines a comparing target code block based on an inclusion relationship of code block. A zero bit plane number comparison unit compares the numbers of zero bit planes of the comparing target code blocks and determines match or mismatch between a specific image and a comparing target code stream. The invention can be applied to, for example, an image comparison apparatus.

Abstract: An encoded code stream is searched for a frame generally coincident with a specific frame without having to decoding the frame to its original image. The present invention provides an image search device that searches an object encoded code stream formed by compression coding of a plurality of frames for a frame generally coincident with a specific one, which includes a decoder for making entropy decoding of the object encoded code stream to generate quantization coefficients of each frame, a matching unit for making matching between the quantization coefficients of the specific frame and those of each frame which are generated by the decoder and correspond in sample position to those of the specific frame, and a judging unit for judging, based on the result of matching, whether the frame is generally coincident with the specific one.

Abstract: This invention relates to a coding method for motion-image data and others effective in a special interactive environment for transmitting motion-image data with information concentrated on only a partial region of a display image as in a two-way interactive system implementing real-time two-way interaction. The coding method involves dividing an image frame forming motion-image data into a plurality of rectangular regions, and grouping each of these rectangular regions into a preset ROI and a non-ROI. These rectangular regions are sequentially compressed so that a code length of a rectangular region grouped into the ROI is larger than a code length of a rectangular region grouped into the non-ROI, thereby generating coded data of each image frame.

Abstract: An encoded code stream is searched for a frame generally coincident with a specific frame without having to decoding the frame to its original image. The present invention provides an image search device that searches an object encoded code stream formed by compression coding of a plurality of frames for a frame generally coincident with a specific one, which includes a decoder for making entropy decoding of the object encoded code stream to generate quantization coefficients of each frame, a matching unit for making matching between the quantization coefficients of the specific frame and those of each frame which are generated by the decoder and correspond in sample position to those of the specific frame, and a judging unit for judging, based on the result of matching, whether the frame is generally coincident with the specific one.

Abstract: A coding parameter extracting unit extracts and supplies coding parameters of a code stream to an image characteristic amount output unit. A code stream characteristic amount extracting unit outputs a first vector calculated based on the number of zero bit planes for each code block extracted by analyzing the code stream. The image characteristic amount output unit uses the coding parameters other than a quantization step size of the code stream to output a second vector calculated based on the number of zero bit planes for each code block of a specific image. A comparing unit compares the first and second vectors for each code block and makes a matching decision between the code stream and the specific image.

Abstract: The present invention relates to an image processing method and image inspecting method with high versatility which enable efficient and highly accurate proof of authenticity of a digital image. The image processing method subjects at least a part of a digital image which can exist temporarily or continuously in a falsification-vulnerable environment, to a first morphology operation using a predetermined structuring element, to process the digital image. The image inspecting method subjects the digital image thus processed, to a second morphology operation using the same structuring element as in the first morphology operation. The morphology operations have the idempotent and the presence or absence of falsification can be detected by determining identity of images before and after the second morphology operation.

Abstract: This invention relates to a coding method for motion-image data and others effective in a special interactive environment for transmitting motion-image data with information concentrated on only a partial region of a display image as in a two-way interactive system implementing real-time two-way interaction. The coding method involves dividing an image frame forming motion-image data into a plurality of rectangular regions, and grouping each of these rectangular regions into a preset ROI and a non-ROI. These rectangular regions are sequentially compressed so that a code length of a rectangular region grouped into the ROI is larger than a code length of a rectangular region grouped into the non-ROI, thereby generating coded data of each image frame.

Abstract: The present invention relates to an encryption key generating method ensuring resistance to collusion attacks and achieving reduction in a key length of encryption keys corresponding to respective hierarchies of each scalability. In the encryption key generating method, an encryption key (K2,2) corresponding to data in the lowest hierarchies of hierarchical scalabilities (R, L) is divided as a master key by the number of hierarchies in scalability (R). Key element matrices (M1-M3) generated with respective split keys (eR2, eR1, eR3) are assigned operation data successively obtained by repeating a hash operation with a one-way hash function, so as to maintain hierarchical nature of scalability (L). Partial keys (K1,1-K2,2) corresponding to respective hierarchies of the scalabilities (R, L) are generated by combining key elements coordinately consistent among the key element matrices (M1-M3).

Abstract: In an image synthesizer (1), code stream analyzers (10, 11), code block extraction units (12, 13) and EBCOT decoders (14, 15) work together to decode encoded code streams (D10, D11) encoded according to the MPEG-2000 Standard and generate quantization coefficients (D16, D17) for each code block. In a cross-fading unit (16), multipliers (17, 18) multiply the quantization coefficients (D16, D17) by coefficients (?(t), (1??(t))) and an adder (19) adds together the results of multiplication to provide a cross-fading quantization coefficient (D20). An EBCOT encoder (20), rate controller (21) and code stream generator (22) work together to encode the cross-fading quantization coefficient (D20) to provide a final encoded code stream (D23). Therefore, the image synthesizer (1) can combine two encoded code streams easily and effectively with a reduced use of a memory capacity.

Abstract: A wavelet inverse transform method includes a decoding object coefficient extracting step of extracting only coefficients necessary for decoding a specified area from wavelet transform coefficients, and a wavelet inverse transform step of inverse transforming coefficients extracted from the decoding object coefficient extracting step. The decoding object coefficient extracting step extracts transform coefficients not only inside the specified area but also those outside the specified area. This enables only an optional partial picture to be decoded without decoding the entire picture. A corresponding wavelet inverse transform device is also disclosed.

Abstract: An encoded code stream is searched for a frame generally coincident with a specific frame without having to decoding the frame to its original image. The present invention provides an image search device that searches an object encoded code stream formed by compression coding of a plurality of frames for a frame generally coincident with a specific one, which includes a decoder for making entropy decoding of the object encoded code stream to generate quantization coefficients of each frame, a matching unit for making matching between the quantization coefficients of the specific frame and those of each frame which are generated by the decoder and correspond in sample position to those of the specific frame, and a judging unit for judging, based on the result of matching, whether the frame is generally coincident with the specific one.

Abstract: A wavelet inverse transform method includes a decoding object coefficient extracting step of extracting only coefficients necessary for decoding a specified area from wavelet transform coefficients, and a wavelet inverse transform step of inverse transforming coefficients extracted from the decoding object coefficient extracting step. The decoding object coefficient extracting step extracts transform coefficients not only inside the specified area but also those outside the specified area. This enables only an optional partial picture to be decoded without decoding the entire picture. A corresponding wavelet inverse transform device is also disclosed.

Abstract: A wavelet inverse transform method includes a decoding object coefficient extracting step of extracting only coefficients necessary for decoding a specified area from wavelet transform coefficients, and a wavelet inverse transform step of inverse transforming coefficients extracted from the decoding object coefficient extracting step. The decoding object coefficient extracting step extracts transform coefficients not only inside the specified area but also those outside the specified area. This enables only an optional partial picture to be decoded without decoding the entire picture. A corresponding wavelet inverse transform device is also disclosed.

Abstract: This invention relates to a coding method for motion-image data and others effective in a special interactive environment for transmitting motion-image data with information concentrated on only a partial region of a display image as in a two-way interactive system implementing real-time two-way interaction. The coding method involves dividing an image frame forming motion-image data into a plurality of rectangular regions, and grouping each of these rectangular regions into a preset ROI and a non-ROI. These rectangular regions are sequentially compressed so that a code length of a rectangular region grouped into the ROI is larger than a code length of a rectangular region grouped into the non-ROI, thereby generating coded data of each image frame.