Abstract: An error diffusion processing circuit includes an error diffusion processing unit and a noise signal unit. The error diffusion processing unit generates a first output image signal of a first pixel by carrying out an error diffusion process, based on an inputted first input image signal of the first pixel. The number of gray tones of the first output image signal is smaller than that of the input image signal. The noise signal unit which generates a noise signal and outputs the noise signal to the error diffusion processing unit. The noise signal is inputted into a feedback loop of the error diffusion process.

Abstract: A broadcast verification system is provided which enables broadcast verification to be performed by a third party being independent of a broadcasting station, without being assisted by another, at low costs and to be reported to a client. The client submits CM (Commercial Message) images to the broadcasting station and registers feature descriptors in a database. When the broadcasting station broadcasts the CM images in accordance with a contract, a receiving device in a checking base extracts contents from received broadcasting waves and a checking section compares feature descriptors of the contents with that of contents stored in the database. When there is coincidence between them, the checking section transmits comparison results to an aggregating section which creates a report including broadcast time, broadcasting channel, broadcasting state and submits it to the client. A broadcast verifying agent receives a broadcast verification entrusting fee.

Abstract: An error diffusion processing circuit includes an error diffusion processing unit and a noise signal unit. The error diffusion processing unit generates a first output image signal of a first pixel by carrying out an error diffusion process, based on an inputted first input image signal of the first pixel. The number of gray tones of the first output image signal is smaller than that of the input image signal. The noise signal unit which generates a noise signal and outputs the noise signal to the error diffusion processing unit. The noise signal is inputted into a feedback loop of the error diffusion process.

Abstract: The present invention relates to a digital watermark insertion system that automatically calculates a digital watermark strength suitable to an input image and inserts a digital watermark into the image. The image categorizing section 103 classifies input images and outputs category indexes. The storage device 101 stores digital watermark characteristic tables describing the correspondences between digital watermark strength, image-quality degradation degree and attack-resistant evaluation value by category index and selects a digital watermark characteristic table to be used according to an input category index. The digital watermark strength calculation section 100 outputs a digital watermark strength to the storage device, calculates an optimum digital watermark strength using an image-quality degradation degree and a resistant evaluation value output from the storage device 103 and constraint information input by an user.

Abstract: The present invention relates to a digital watermark insertion system that automatically calculates a digital watermark strength suitable to an input image and inserts a digital watermark into the image. The image categorizing section 103 classifies input images and outputs category indexes. The storage device 101 stores digital watermark characteristic tables describing the correspondences between digital watermark strength, image-quality degradation degree and attack-resistant evaluation value by category index and selects a digital watermark characteristic table to be used according to an input category index. The digital watermark strength calculation section 100 outputs a digital watermark strength to the storage device, calculates an optimum digital watermark strength using an image-quality degradation degree and a resistant evaluation value output from the storage device 103 and constraint information input by an user.

Abstract: The present invention relates to a digital watermark insertion system that automatically calculates a digital watermark strength suitable to an input image and inserts a digital watermark into the image. The image categorizing section 103 classifies input images and outputs category indexes. The storage device 101 stores digital watermark characteristic tables describing the correspondences between digital watermark strength, image-quality degradation degree and attack-resistant evaluation value by category index and selects a digital watermark characteristic table to be used according to an input category index. The digital watermark strength calculation section 100 outputs a digital watermark strength to the storage device, calculates an optimum digital watermark strength using an image-quality degradation degree and a resistant evaluation value output from the storage device 103 and constraint information input by an user.

Abstract: A broadcast verification system is provided which enables broadcast verification to be performed by a third party being independent of a broadcasting station, without being assisted by another, at low costs and to be reported to a client.

Abstract: The invention provides a reversible eight-element discrete cosine transform system which can be realized with a practical circuit and provide transform values proximate to those obtained by actual eight-element discrete cosine transform. In 4×4 matrix transform which appears when eight-element discrete cosine transform is decomposed in accordance with a high speed calculation method, transform values (X1, X7, X3, X5) are divided into (X1, X7) and (X3, X5), and if (X1, X7) are determined, then possible values as (X3, X5),are limited. This is utilized for quantization of the elements. (X1, X7) are quantized with step sizes of k1 and k2 by operators to obtain quantization values (Q1, Q7).

Abstract: The invention provides a coding system and a decoding system wherein a discrete cosine transform which provides a high coding efficiency is approximated to allow reversible coding and decoding while maintaining the high coding efficiency and a system which includes such coding and decoding systems. Reversible coding is realized by multiplying a transform matrix by a fixed number for each row to approximate the transform matrix with integer values, performing re-quantization in a basic region defined by a multiple of a determinant for suppressing redundancy while maintaining a condition wherein reversible coding is possible in the basic region, and performing re-quantization for the entire region making use of the fact that such basic region appears periodically in a signal space.

Abstract: The invention provides a reversible eight-element discrete cosine transform system which can be realized with a practical circuit and provide transform values proximate to those obtained by actual eight-element discrete cosine transform. In 4.times.4 matrix transform which appears when eight-element discrete cosine transform is decomposed in accordance with a high speed calculation method, transform values (X.sub.1, X.sub.7, X.sub.3, X.sub.5) are divided into (X.sub.1, X.sub.7) and (X.sub.3, X.sub.5), and if (X.sub.1, X.sub.7) are determined, then possible values as (X.sub.3, X.sub.5), are limited. This is utilized for quantization of the elements. (X.sub.1, X.sub.7) are quantized with step sizes of k.sub.1 and k.sub.2 by operators to obtain quantization values (Q.sub.1,) Q.sub.7). Meanwhile, from (X.sub.3, X.sub.

Abstract: For digital signals provided with motion vectors of a plurality of regions, a conversion coefficient for a respective one of the motion vectors is determined in accordance with the respective motion vector and a shape of a corresponding one of the regions on which the respective motion vector represents a motion, linear conversions of the digital signals are performed by using the respective coefficients of the motion vectors, and an accumulation is made of results of the conversions for the respective motion vector by the linear conversion step so that the linear conversions are overlapped with each other.

Abstract: The invention provides a coding system and a decoding system wherein a discrete cosine transform which provides a high coding efficiency is approximated to allow reversible coding and decoding while maintaining the high coding efficiency and a system which includes such coding and decoding systems. Reversible coding is realized by multiplying a transform matrix by a fixed number for each row to approximate the transform matrix with integer values, performing requantization in a basic region defined by a multiple of a determinant for suppressing redundancy while maintaining a condition wherein reversible coding is possible in the basic region, and performing requantization for the entire region making use of the fact that such basic region appears periodically in a signal space.

Abstract: A motion compensation circuit comprises finite impulse response (FIR) filters divided into N groups according to N subbands of input video signal samples. One of the FIR filters of each group receives a delayed version of the subband of the group, and the remainder of the group receives a delayed version of one or more of the subbands which are adjacent to the subband of the group. Each FIR filter has tap-weight multipliers controlled in response to an estimated motion vector for shifting sample points of each subband. N adders are provided corresponding respectively to the N groups of FIR filters for summing the outputs of the FIR filters of the corresponding groups to produce N motion compensation signals.

Abstract: In a subband coding device for coding a digital device input signal which is a one-dimensional or a two-dimensional signal, a single coding circuit is used instead of a conventional combination of coders and a multiplexer. The coding circuit is for coding subband samples of different frequency bands in each sample group across the frequency bands, as by starting from a lowest frequency band and ending at a highest frequency band or reversedly, and preferably with attention directed to correlation which the subband samples have between two adjacent frequency bands. Zero-level components of the subband samples are preferably run-length coded. When the subband samples of each sample group have a tree structure including subtrees, the subband samples are preferably scanned from a subtree to another subtree either starting at or ending at the subband sample of the lowest frequency band.

Abstract: In a predictive coding device responding to a sequence of image data signals representative of picture elements to produce a sequence of coded output signals, a plurality of provisional error signals are calculated for each picture element from the image data signals and different provisional prediction signals sent from predictors and are given weights in multipliers from a weight decision circuit in consideration of a position of each picture element to produce weighted error signals. The weighted error signals are summed up into a first sum signal by a first adder circuit and thereafter processed into the coded output signals and local decoded signals which are sent to the predictors. The predictors may carry out either different prediction from one another for each picture element or identical prediction in relation to different blocks.

Abstract: In a decoding device for decoding an input signal into a decoded signal, a delay circuit delays the decoded signal into a delayed signal with a delay equal to a frame period of a digital video signal which is encoded into an encoded signal by interframe predictive encoding. A forward filter of a predetermined filtering characteristic filters the delayed signal into a first filtered signal. An adder adds the input signal to the first filtered signal to produce an added signal. A subtracter subtracts the input signal from the delayed signal to produce a subtracted signal. An inverse filter filters the subtracted signal into a second filtered signal.

Abstract: In a reproduction system for use in reproducing a still image from a sequence of predictive error signals which is read out of a memory and which is preliminarily processed into a sequence of preliminary processed signals, an intermediate circuit interrupts the preliminary processed signals in response to an external command signal. In the intermediate circuit, the external command signal is resampled by a sequence of frame pulses in a resampling circuit into a resampled signal so as to close a gate circuit. No predictive error signal is sent to an adder circuit during absence of the gate circuit. An identical error signal is repeatedly produced as a sequence of reproduced signals to reproduce the still image.

Abstract: In an image processing system for use in processing a sequence of image signals carrying a moving image, the image signal sequence is divided into a sequence of partial image signals each of which carries a scene subsequence defined by scene changes. A background signal generator determines a background portion of the moving image by monitoring a whole of each partial image signal and produces a background signal. The background signal is coded by a coder prior to a sequence of error signals resulting from predictive coding of each partial signal. During prediction of the background signal, the error signals may be rendered to zero in the coder. The background signal may be either determined at every picture element or at every block composed of a plurality of picture elements.

Abstract: On subjecting a digital video signal of successive pictures to redundancy reduction coding, a mode signal is produced which indicates, as the redundancy reduction coding, a selected one of interframe coding and intraframe coding. The digital video signal is selectively subjected to the selected one of the interframe and the intraframe coding in response to the mode signal. A particular picture element of a current picture is subjected to the intraframe coding when the mode signal indicates that the particular picture element should be subjected to the interframe coding and that a corresponding picture element of a following picture following the current picture should be subjected to the intraframe coding. The mode signal and results of the interframe and the intraframe coding are multiplexed into a multiplexed signal.

Abstract: In a recording system, a sequence of image signals obtained from a sequence of images are used to generate and record a sequence of recordable signals on a read only memory. Efficient coding of the received sequence of image signals is carried out through the use of a given parameter which is adaptively and dynamically changed, preferably manually, through a parameter controller acting as the interactive device. The image signals are repeatedly subjected to the efficient coding process. The process uses a sequence of predictive signals to produce coded signals. The predictive signals are displayed on a monitor display device to be monitored by an operator. The operator changes the attributes of the parameter until an optimum image is obtained. The optimum parameter is stored on a magnetic tape.