Abstract: According to orthogonal transformation coefficients obtained through orthogonal transformation, the degree of influence on visual sensation is detected. Depending on the degree of influence on visual sensation, a quantization step size is controlled so as to assign a greater amount of codes to each block of which image quality deterioration is conspicuous and a smaller amount of codes to each block of which image quality deterioration is less conspicuous.

Abstract: An encoding and decoding apparatus for a video signal and a high-definition television signal is disclosed. For the picture A having the horizontal to vertical screen frame ratio of 4:3, the picture B having the horizontal to vertical screen frame ratio of 16:9 and the picture C having the horizontal to vertical screen frame ratio of 16:9 and having a larger number of vertical pixels than that of the picture A and picture B, the apparatus limits the band of the picture C to obtain the picture D having the same numbers of horizontal and vertical pixels respectively as those of the picture B, and high-efficiency encodes the picture A, picture B or picture D in the same method. The apparatus obtains the additional picture E which is a difference between the picture D and the picture C, or a difference between the picture D' which is a result of decoding a signal that has been obtained by high-efficiency encoding the picture D and the picture C, and then high-efficiency encodes the additional picture E obtained.

Abstract: Disclosed are a video signal recording apparatus for dividing digital video signal into blocks, transforming orthogonally, quantizing, coding in a variable length, and recording always in identical data quantity in a unit of specific number of blocks, and a video signal reproducing apparatus for decoding the recorded signal in variable length, quantizing inversely, transforming inversely and orthogonally, and reproducing the original digital video signal. The coding data in the specific number of blocks in the identical data quantity is divided in two code rows, the individual low frequency components are assigned to separate sync blocks, and high frequency components are also assigned to separate sync blocks, and recorded. When reproducing, if the sync block of high frequency components is wrong, it is possible to decode only with low frequency components, and the screen is reproduced at high fidelity to the reproducing speed at the time of high speed reproducing.

Abstract: In digital video signals which differ in the number of pixels thereof, such as a standard video signal having a screen aspect ratio of 4:3 and a wide video signal having an aspect ratio of 16:9 the data quantity after encoding is equalized without increasing the compression ratio of the video signal having the larger number of pixels. An encoding apparatus performs intraframe encoding of the standard video signal so that the coded data quantity is constant in every frame, and interframe encoding of the wide video signal in each two frames so that the coded data quantity is constant in every two frames.

Abstract: In an apparatus for executing an algorithm for realizing an orthogonal transform operation such as the 8 points fast cosine transform, by operating on successive sets of data values of a digital signal such as a digital video signal in such applications as high efficiency coding of a digital video signal, a plurality of multiplication operations that are executed during processing of each set of data values are executed sequentially by time division multiplex operation of a single multiplier (32) which is capable of executing a multiplication operation within one sample period of the digital signal, with input and output data values being transferred by selector units (11, 33, 41) between the multiplier and other sections of the apparatus at appropriate times during processing of each set of the input digital signal values. The scale of hardware required for the apparatus is thereby reduced by comparison with an apparatus which employs a plurality of separate multipliers.

Abstract: A decimation or interpolation filter is selectively used for decimation or interpolation of pixel data of a chrominance component of a video signal, In general, the chrominance signal and the luminance signal are closely related to each other and their edge pattern data coincide with each other when reproduced on a picture screen. A filter device for decimation or interpolation of the chrominance signal is arranged to perform a number of filtering actions depending on the presence or absence and location of edge pattern data. The present, absence, and location of the edge pattern data is detected using a luminance signal which is neither decimated nor interpolated.

Abstract: A record unit of coded video data is concealed. The record unit is reproduced from a recording medium and has a first recording block containing a part of a coded video data A which has been obtained by coding m blocks of video data among a plurality of blocks of video data divided from video data of one page, a second recording block containing a part of a coded video data B which has been obtained by coding other m blocks of video data among the plurality of blocks of video data and a third recording block containing in a first part thereof the remaining part of the coded video data A and in a second part thereof the remaining part of the coded video data B. The record unit also contains an address data indicating an address of a border of the first and second parts of the third recording block.

Abstract: In a digital video signal recording/reproducing apparatus for recording digital VCR video and audio signals by using a rotary cylinder, for a video signal with a frame frequency fN of 30 Hz or 29.97 Hz, the rotating frequency of the cylinder is set to 2.5 times fN. On the other hand, for a signal with a frame frequency fP of 25 Hz, the rotating frequency of the cylinder is set to 3.0 times fP. As a result, as long as the cylinder diameters are identical, the relative speed of the tape and the head is the same for video signals of either frame frequency fN or fP.

Abstract: An information recording apparatus implements the orthogonal transformation for the input signal on a block-by-block basis, separates each variable-length coded word into a fixed part and separate part individually, records the fixed part into a record block which is established for each block of orthogonal component by starting from the beginning and ending at the prescribed position of the record block, and records coded words of the separate part into remaining portions of record blocks.

Abstract: Disclosed is an orthogonal transformation encoder in which after horizontal orthogonal transformation is performed, in parallel to the horizontal and vertical rearrangement of the coefficients for performing vertical orthogonal transformation, detection of interfield coefficient is performed and intra-frame/intrafield modes for the vertical orthogonal transformation are switched. Further, in parallel to the rearrangement of the transformation coefficients for the vertical orthogonal transformation to be in the ascending order from a lower frequency component to a higher frequency component, the amplitude values of the AC components in the block in question are detected to thereby make control on the basis of the amplitude values so that the smaller the amplitude value of the block the smaller the quantizing step width.

Abstract: In an encoder for selectively receiving, blocking and coding by orthogonal transformation an image A with a screen aspect ratio which is greater than 4:3 or an image B with a screen aspect ratio of 4:3, when the image A is entered, it is divided into a basic screen with an aspect ratio of 4:3 corresponding to a central portion of a screen and an additional screen other than the basic screen. Coding is controlled so that a sum of coded data quantity of a specified number of blocks m of orthogonal transformation of the basic screen and a specified number of blocks n of orthogonal transformation of the additional screen is within a specified data quantity x. When the image B is entered, the coding is controlled so that a coded data quantity of the same number of blocks of orthogonal transformation as the specified number of blocks of orthogonal transformation m of the basic screen of the image A is within the same data quantity as the specified data quantity x.

Abstract: A digital video signal is shuffled such that blocks of a luminance signal and a chrominance signal existing at a same position on an image plane are contained in a same segment recorded on a recording medium or in a plurality of segments recorded simultaneously in parallel using a plurality of channels. Thus, the luminance signal and chrominance signal being at the same position on the image plane are always obtainable simultaneously even during high-speed reproducing in a digital VTR.

Abstract: A video signal digital recording and reproducing apparatus includes: a rearranging section for rearranging a sequence of signals on a rectangular unit by rectangular unit basis formed by sectioning a group of pixel data on a screen of a digital video signal; an encoding section for subjecting the signals in the rectangular units to bit rate reduction; a block forming section for gathering plural number of the coded rectangular units to constitute a block of signals, and a recording the block of signals section for recording on a recording medium. The rearranging section divides the screen into plural regions, takes out the rectangular units by a certain number in order from each region, and carries out rearrangement so that mutually corresponding rectangular units which are contained respectively in adjacent blocks on the recording medium are mutually adjacent on the screen.

Abstract: A variable length code encoder is provided in which, during variable length code encoding of video or audio data which has been divided into blocks for ease of transmission or storage, the lowest bit of a particular variable length code in each block of code words which is composed of a special pattern of bits and arranged to appear at no other position than the end of the block, is utilized for carrying a piece of data in addition to the data of the block.

Abstract: A maximum value of each block after orthogonal transformation is detected, and an output word length after orthogonal transformation is controlled in accordance with the maximum value thus detected. In addition, a plurality of tables each having a plurality of quantizers combinedly used are prepared and a table is selected in accordance with the maximum value of each block, thereby selecting the optimum quantizer in accordance with the data amount thus generated.

Abstract: A method for transmission of variable length code words is provided in which the variable length code words are allocated into a data storage field not only from the front end of the same but also from the rear end, whereby unwanted affection by transmission error will be minimized. A coding apparatus produces coded data of such a format that after different type video signals are divided into a common signal area and a not-common signal area, the coded data of the common signal area is allocated into one data storage field in a sequence from the front end of the same and the coded data of the not-common signal area is allocated in a reverse sequence from the rear end. Accordingly, such different video signals can successfully be decoded with a decoder designed for processing one particular video signal.

Abstract: A video signal recording/reproducing apparatus which records pictures by compressing the video signal in multiple field units and reproduces an signal by the expansion process, and which continuously and repeatedly outputs each field of the reproduced television signal on the screen by use of a field detecting unit which operates to ensure that a reciprocal of a multiplication index of a desired reproducing speed is selected as a number of continuous reproductions of one field and also by use of a change-over unit for changing over the reproduced signal in field units.

Abstract: A video signal compression apparatus in which a video signal having a non-matrix pixel arrangement is separated into a plurality of partial images each having a matrix pixel arrangement. The partial images thus separated are interpolated into those containing low-frequency components and those having high-frequency components. The partial images having low-frequency components are coded by an orthogonal transformation while those having high-frequency components are coded by a non-linear quantization or orthogonal transformation. The amount of data is adaptively assigned from the code length of the partial images having high-frequency components to those having low-frequency components, thus effectively utilizing the orthogonal transormation coding which has a great compression effect on a video signal having a non-matrix pixel arrangement.

Abstract: A non-linear signal processing apparatus used in a video tape recorder or a video disk player is disclosed. The time variation of an input signal or a processed version thereof is non-linearly processed by a differential circuit and a closed loop including a non-linear circuit. The non-linearly processed time variation of the signal or a processed version thereof is arithmetically combined with the input signal. Thus, the same non-linear characteristic as that obtained by the prior art analog signal technique is attained by the digital signal processing technique, which is superior in integrity and stability. By appropriately selecting the characteristic of the non-linear circuit, better results than those obtainable by the analog signal processing technique are achieved.

Abstract: A loudspeaking telephone system has a voice switch circuit in which voice signals on transmission and reception speech channels are respectively detected to produce control signals, and these control signals are compared to judge the levels of the voice signals on both the speech channels so that the switching between both the channels is effected under the control of loss of variable attenuators inserted in both the speech channels. The control signals corresponding to the voice signals on both the transmission and reception speech channels are converted through analog-to-digital conversion into digital values which are suitable for arithmetic operation. The arithmetic operation is such that the losses of the variable attenuators are automatically controlled in accordance with the use conditions of the loudspeaking telephone system to minimum values which can prevent the howling, transmitting blocking and receiving blocking.