Abstract: The text to speech conversion system distinguishes geographical names based upon the present position and includes a text input unit for inputting text data, a position coordinator input unit for inputting present location information of the text to speech conversion system, and a text normalizer connected to the text input unit and the position coordinator input unit for capable of generating a plurality of pronunciation signals indicative of a plurality of pronunciations for a common portion of the text data, the text normalizer selecting one of the pronunciation signals based upon the present location information.

Abstract: A video data transmitting and receiving system which compresses an amount of information of a video signal at a compression rate in accordance with a transmission mode, directly modulates the video signal after compression in accordance with the transmission mode or once records the video signal by a recording and reproducing apparatus and then reproduces the same with a different rate from that at the recording, detects the transmission mode at a reception side, directly decodes this in accordance with the detected transmission mode or once records the same, reproduces this at a different rate from that at the recording and then decodes the resultant data.

Abstract: A video signal recording and reproduction apparatus, provided with at least one encoding apparatus for encoding an input video signal, at least one data storage apparatus for recording and reproducing a video signal encoded by the encoding apparatus, a line switching apparatus for selectively connecting the encoding apparatus and data storage apparatus or selectively connecting the data storage apparatus and an output line of the video signal; and a control apparatus for controlling the line switching apparatus and the data storage apparatus in accordance with a recording command or reproduction command.

Abstract: In this invention, it is possible to realize a video signal output apparatus having so called Near Video On Demand function such that, in respective reproducers of a plurality of reproduction blocks within a video reproduction section, with respect to a plurality of divided image sources obtained by dividing an image source into image sources of a plurality of time zones, divided image sources of the same time zone are simultaneously repeatedly reproduced in the state where they are respectively shifted by a predetermined time to carry out switching between a plurality of video signals delivered from the plurality of reproducers by a video select switch to thereby provide successive image sources, without being conscious of time and switching operation of image sources reproduced in accordance with selection of a desired image source by the viewer also with respect to image source of data quantity corresponding to time longer than the memory capacity of each of media of the reproducers.

Abstract: A technique for processing a decoded image signal having a distortion obtained by decoding coded data by utilizing a two-dimensional inverse orthogonal transformation in which the coded data is obtained by coding an image signal by utilizing a two-dimensional orthogonal transformation. At least one correction block is constructed each including a plurality of pixels from a plurality of coded blocks from the decoded image signal and having a distortion on at least one boundary therebetween. The coded blocks of each correction block are adjacent to one another. A two-dimensional orthogonal transformation of each the correction block is performed by utilizing a Haar function so as to form a plurality of coefficients including higher-order side coefficients, lower-order side coefficients and a dc coefficient.

Abstract: In a picture signal coding/decoding method and a picture signal coding/decoding device, the compressibility and visual picture quality of the picture pattern whose inter field correlation of high frequency decreases and inter field correlation of low frequency remains when slow movement occurs are improved and transmitted. The intra field component separate coding is performed in each field on the first and second fields of picture signal respectively, and by preventing the effect of inter field movement in advance, the dropping of compressibility by the movement is avoided and furthermore, new blocks is constructed by the resultant low frequency components of two fields and since it is so arranged that the component separate coding is performed in the frame, low frequency components which are not easily affected by slow movement can be coded efficiently, and as a result, the compressibility for the picture containing slow movement can be increased.

Abstract: A data transmission system, permits data transmission without failure while ensuring a substantially constant picture quality or audio quality irrespective of the source of data. The data transmission system transmits data after conversion thereof into digital data and compression of the same. In the system, the distortion in data to be transmitted is measured, and the quantization step size is controlled according to the measured distortion to hold the distortion constant, thus permitting data transmission while maintaining constant quality of the transmitted data irrespective of the data source kind.

Abstract: The video signal containing portions locally unsuitable for coding is divided into a plurality of components and is coded by a method such as a Wavelet transform and then is transmitted. In this case, a first quantizing means controls a quantization characteristic per block consisting of small area segments of coefficients composed of respective components to make uniform a distortion within the picture and a visual obstacle caused by the distortion. A second quantizing means controls the quantization characteristic to make uniform a deterioration quantity of the entire picture within a range of a predetermined coded data quantity. It is therefore possible to effect the transmission with a stable picture quality against a variety of fluctuations in the video signal inputted.

Abstract: A Viterbi decoding apparatus includes a brand metric calculation circuit for calculating a branch metric for a plurality of time slots at one time by an add-compare-select-state-metric (ACS-SM) calculation circuit for performing add-compare-select (ACS) calculation an add-compare-select-state-metric calculation circuit according to a branch metric for a plurality of time slots obtained by the branch metric calculation circuit and a state metric in the preceding stage at intervals of a plurality of time slots, and a maximum likelihood sequence decision circuit for decoding input data according to the content of the path obtained through the ACS calculation, wherein on the outside of a loop composed of the ACS-SM normalization circuit and a state metric storage circuit, there is provided a normalization command circuit, whereby a decision as to the necessity for normalization, a setting of the timing of normalization, and the like are performed, and, when it is decided that normalization is necessary, the state

Abstract: In a video signal transmission system in which input video signals are high efficiency coded for transmitting, the high efficiency coded data are decoded with quantization information determined for each block group by the amount of the data remaining in the buffer memory. The decoded data are compared with the original video data to determine the difference data. The difference data are weighted with a flatness value which defines the degree of perceivability of the distortion. The quantization size for the video data to be transmitted actually is determined based on the difference data or the weighted difference data so that the quality of the picture to be transmitted can be improved.

Abstract: A Viterbi decoding apparatus capable of decoding convolutional codes of 30 Mbps or more in information quantity for such applications as high-definition television broadcasting. The apparatus comprises a path memory circuit and an ACS.SM normalizing circuit. The path memory circuit is made of path memory cells arranged in matrix fashion for shifting a path decoded word in units of a plurality of time slots in accordance with a transition diagram corresponding to that plurality of time slots and on the basis of path selection signals from the ACS.SM circuit that calculates data in units of that plurality of time slots.

Abstract: A Viterbi decoding apparatus for decoding received data by Viterbi decoding comprising a state metric memory circuit, a path memory circuit, and a path decode word decision circuit. The state metric memory circuit stores state metric information obtained by ACS (Adder, Comparator, Selector) processing. The path memory circuit stores path selection information provided by the ACS processing. The path decode word decision circuit weights a plurality of bits with a path decode word of each state according to its degree of likelihood based on state metric information supplied from the state metric memory circuit, cumulatively adding each path decode word obtained by the weighting operation, and comparing a cumulative value obtained by the cumulative adding operation with a preset threshold value to determine decode words.

Abstract: A scrambling/descrambling circuit that may be manufactured as a CMOS arrangement in LSI format and free of constraints on the degree of the generating polynomial involved. Scrambled (or descrambled) "m" bits of data output by registers are multiplied by multiplication circuits by a factor of the generating element .alpha..sup.m of the generating polynomial. The multiplied data are input back to the registers. The scrambled "m" bits of data are supplied to "m" exclusive-OR gates for exclusive-OR operation with input data.

Abstract: An apparatus for decoding BCH code having first, second and third circuits for generating a syndrome S1, a syndrome S3 and a parity P, respectively from a receiving sequence, a fourth circuit coupled to the first circuit for generating S1.sup.2 from the syndrome S1, a fifth circuit coupled to the first circuit, second circuit and fourth circuit for generating (S1.sup.3 +S3), a Chien search circuit which includes a first generating circuit supplied with the S1 and S1.sub.2 for generating a first stage of error-location polynomial A, where A=S1.alpha..sup.-2n +S1.sup.2 .alpha..sup.-n, and a second generating circuit supplied with the (S1.sup.3 .alpha.+S3) and the A for generating a second stage of error-location polynomial B, wherein B=A+S1.sup.3 +S3, and an error correction and detection logic circuit supplied with the S1, P, (S1.sup.3 +S3), A and B and with a decode selection signal and a BCH code selection signal for generating an error correction or detection signal.

Abstract: A highly efficient coding apparatus is made for developing a prediction value from a value which is ahead in time, correlation. The apparatus comprises, first to M-th prediction circuits supplied with a picture signal of each of M areas which divide a picture composed of plural lines, each consisting of plural picture elements and generating output, respectively, the first prediction circuit having structure for selecting a prediction value generated by itself and an initial value, the prediction circuits other than the first prediction circuit having structure for selecting prediction values generated by themselves and other prediction values generated by the prediction circuits for processing divided areas adjacent in space and being ahead in time, whereby the other prediction circuits select other prediction values through the selecting structure at timing of processisng of picture element data which is closest to the border of the divided areas.

Abstract: According to the present invention, when video data of, for example, a real moving picture is transmitted, the video data is data-compressed and transmitted while the combination of the compressing ratio of the video data and the encoding ratio of the video data is varied in response to a condition of the transmission path. Therefore, regardless of the condition of the transmission path, video data of the best quality can be transmitted at a constant transmitting speed.

Abstract: In transmitting a residual signal determined by the difference between an input signal and a predictive signal, a comparative signal based on the input signal is applied to a plurality of predictors having different respective predictive functions or coefficients, the resulting predictive output signals from the predictors, respectively, are compared with the comparative signal to provide respective difference signals, and the predictor corresponding to the smallest of the difference signals with a predetermined time delay, for example, the next preceding sampling of the input signal, is employed as the source of the predictive signal to be subtracted from the input signal for determining the transmitted residual signal.

Abstract: A waveform shaping circuit for use with a digital signal transmission apparatus includes an N stage shift register having a digital data input terminal and first and second sets of output terminals, a pair of read only memories each having a plurality of address control terminals controlled by the output signal from the first and second sets of output terminals of the shift register and an output signal, an adder supplied with the output signals from the pair of read only memories so as to produce a digital output signal to be D/A (digital-to-analog)-converted.

Abstract: Apparatus for decoding BCH code can correct double errors using a modification of the Chien search method. This decoding apparatus comprises circuits to form syndromes S1 and S3; a circuit to form S1.sup.2 ; a circuit to form S1.sup.3 ; a circuit to form (S1.sup.3 +S3); and Chien search circuit, in which the error-location polynomial .sigma.(x)=(S1x.sup.2 +S1.sup.2 x+S1.sup.3 +S3) is solved, thereby correcting errors of two or less. With this apparatus, there is no need to perform a dividing process, and a high decoding processing speed can be realized without using any PLA or ROM.

Abstract: A method of recording a digital data signal, such as an audio PCM signal, onto a recording medium in the longitudinal direction thereof, together with an apparatus which is suitable for this recording method. Even-numbered words and odd-numbered words in a digital data signal are recorded on a first track group and a second track group, respectively, which are separated from each other in the widthwise direction of a recording medium, to prevent a series of words becoming error words because of, for example, a flaw in the recording medium in the longitudinal direction thereof. The data format is changed at the input and output of a recording encoder to enable an error correction code and a recording circuit to be used in common for digital tape recorders which have different numbers of tracks, e.g., n tracks and 2n tracks.