Abstract: A composite video signal generator, which can be simply implemented using an application-specific integrated circuit (ASIC), is provided. The composite video signal generator according to the present invention has an oscillator for generating a clock signal at 4.multidot.f.sub.x of a color burst signal. A color burst generator creates the color burst signal by dividing the frequency of the clock signal and switching the divided clock signal according to a first control signal. A color signal is generated by phase-shifting the clock signal according to a second control signal to produce a phase-shifted clock signal, and dividing the frequency of the phase-shifted clock signal. The angle of the phase-shifting corresponds to a particular color. A luminance signal processor converts received luminance data into an analog luminance signal according to a third control signal.

Abstract: The signals received by the three cameras of any color video system are determined by the reflectance properties of the objects in the scene and the spectral distribution function of the illuminant. Since the information of interest to the observer is determined by the scene and not by the illuminant i.e. what kind of objects, characterized by their reflectance properties, are in the scene, not how they are illuminated, it is desirable to correct the signals from the scene for the illuminant before the information is displayed on the CRT. According to the invention, a color video system employs the achromatic variable .xi., where .xi., 0.ltoreq..xi..ltoreq.1, and preferably also the chromatic variables .eta., .zeta.

Abstract: A video signal processing apparatus includes an equalizer for delaying an input color signal by an adjustable phase retardation. A low pass filter is operative for delaying the input color signal by an adjustable phase retardation. A phase detector is operative for detecting a difference between a phase of an output signal of the equalizer and a phase of an output signal of the low pass filter, and outputting a signal representative of the detected phase difference. The phase retardation provided by the equalizer and the phase retardation provided by the low pass filter are adjusted in response to the output signal of the phase detector to maintain the difference between the phase of the output signal of the equalizer and the phase of the output signal of the low pass filter at a predetermined value, for example, 90 degrees.

Abstract: A carrier chrominance signal forming device is provided with input parts for receiving a plurality of kinds of complementary color signals and a carrier chrominance signal forming part for forming a carrier chrominance signal by performing computing operations on the complementary color signals received by the input parts. These parts are arranged to enable the device to stably form a carrier chrominance signal from the complementary color signals with a compact circuit arrangement.

Abstract: A digital-to-analog video encoder method and apparatus having unique equalization are disclosed. The encoder converts digital video signals into one or more analog video formats using one or more digital-to-analog converters. Equalization is provided to compensate for zero order hold effects of the digital-to-analog converters. Equalization is provided to a luminance signal and/or a chroma signal to equalize RGB, composite video, and super VHS video outputs. Multiplexed digital-to-analog converter inputs allow selection of several output formats.

Abstract: There is provided a video retrieval method, and apparatus, capable of fast matching a feature of a target video with a feature of an enquiry video without conducting work of providing keywords for video retrieval. As for the target video, both a video which is being broadcasted and a video included in a data base can be dealt with.

Abstract: A digital amplitude and phase detector for detecting the amplitude and phase of a color burst digital signal used in television systems is provided. The detector comprises a phase lock loop circuit for detecting the phase of said color burst signal and for generating a synchronous constant amplitude sinusoidal signal; multiplying circuit for generating a product signal by multiplying the color burst signal by the constant amplitude sinusoidal signal, wherein said product signal has a high-frequency component and a low-frequency component having an amplitude substantially proportional to that of the color burst signal; and low pass filter circuit coupled to said multiplying circuit for filtering said product signal such that the high-frequency component is substantially suppressed relative to that of the low-frequency component. A video encoder using the digital amplitude and phase detector is also provided.

Abstract: A data encoding system for encoding input color pixel data and outputting encoded data. The data encoding system includes a reference pixel generating device which outputs reference pixel data corresponding to the input color pixel data to be encoded; a predictor having a color order table which sets the color ranks of color codes for every reference pixel pattern, reads and outputs the color rank of the corresponding color code from the color order table on the basis of the color pixel data to be encoded and its reference pixel data; and an entropy encoding device which converts the color ranking data into encoded data and outputs the encoded data.

Abstract: A data register for providing data values to an n-element parallel processing array includes a memory buffer having first and second memory modules, where each module includes n columns of data values. An address decoder receives an address for accessing n data values at a time from the memory modules and asserts address values to access corresponding rows of the first and second memory modules. Select logic selects between respective columns of the first and second memory modules to retrieve the desired data values according to a predetermined order. A shift network reorders the retrieved data values, if necessary, to place them in the proper order for the processing array. The address decoder provides a select value to the select logic and a shift value to the shift network for each cycle. For purposes of horizontal decimation, the pixel values are organized into an even and an odd group, which groups are stored in the memory buffer in two separate regions separated by an address offset K.

Abstract: A digital encoder includes a matrix circuit for synthesizing chrominance signals R-Y and B-Y based on RGB signals sampled at a predetermined sampling frequency which is an integral multiple of a chrominance subcarrier; low-pass filters; a delay circuit; a switch circuit for reducing a frequency of an output from the low-pass filters; a digital modulator for subjecting a chrominance subcarrier to quadrature two-phase balanced modulation using an output signal from the switch circuit so as to output a chrominance signal having a sampling frequency 1/m that of the predetermined sampling frequency; a sampling frequency conversion circuit for multiplying the sampling frequency of the chrominance signal by a factor of m so as to output a chrominance signal having the predetermined sampling frequency; and an adder for computing a sum of the luminance signal delayed by the delay circuit, the chrominance signals output by the sampling frequency conversion circuit and a composite synchronizing signal so as to synthesiz

Abstract: A video quality improvement method and apparatus for a television system recovers lost brightness information from the chrominance channels of an encoder due to processing errors, such as quantization roundoff errors, and adds it to the luminance input to the luminance channel of the encoder. Component signals from a video source are input to the encoder. The encoder provides an encoded video output signal as well as reconstructed component signals. From the encoder characteristics the processing errors for the chrominance channels are determined. The partial derivatives for each of the component signals are obtained, and the error in brightness is determined by summing the products of the errors and the corresponding chrominance partial derivatives. The luminance component signal is corrected by dividing the error in brightness by the luminance partial derivative and subtracting the result from the input luminance component signal. The corrected luminance component signal is processed by the encoder.

Abstract: In data processing wherein image data are processed by dividing them into blocks, a chroma data W is obtained from the color difference data W.sub.R and W.sub.B, and the color difference data W.sub.R and W.sub.B are corrected according to an amplitude of the chroma data W. For example, if the chroma W is smaller than a prescribed threshold value, the color difference data W.sub.R and W.sub.B are set as zero. Then, the so-called block distortion can be prevented. The degree of the correction may depend on the amplitude of the chroma data W. On the other hand, DC coefficients of discrete cosine transform coefficients of adjacent blocks are compared with each other. When the DC coefficients are different from each other, block distortion occurs if they represent a same image. Then, if differences of DC coefficients of discrete cosine transform coefficients of adjacent blocks are small with each other, the DC coefficients are corrected to tend to have similar values.

Abstract: In a component video signal to composite video signal encoding system (10), the component input signals are stored in a first in, first out (FIFO) memory. The FIFO memory is connected by 1 luminance and 2 chrominance outputs to a rate converter, which increases the digital sampling rate of the signals as received from the FIFO memory. The rate converter is in turn connected by 1 luminance and 2 chrominance outputs to luminance and chrominance processing circuits. The luminance and chrominance processing circuits produce the composite video signals, and are connected to a D2 standard driver circuit. The output of the D2 driver circuit is D2 standard digital component signals. The luminance and chrominance processing circuits are also connected to a digital to analog (D/A) converter. The output of the D/A converter is an analog PAL or NTSC component video signal.

Abstract: An image signal processing apparatus is arranged to convert input analog color-difference signals into digital color-difference signals, form a digital chrominance signal by using the digital color-difference signals, multiplex the formed digital chrominance signal onto the digital color-difference signals, convert the formed digital signal into an analog signal, and separate the analog signal into color-difference signals and a chrominance signal. With this arrangement, it is possible to simplify the arrangement of the apparatus and reduce the size, weight and cost thereof.

Abstract: A video storage arrangement produces a continuous video signal representing a test pattern. One luminance frame store is provided and two chrominance frame stores. A selection can be made between NTSC, PAL and SECAM modes. Switches are provided for selecting between chrominance frame stores and between inverting and non-inverting mode. Depending upon the selected broadcast standard, these switches are driven from field and line clock signals to generate the required output field sequence in YC or composite form.

Abstract: After an initial starting single color may or may not be provided, the user may indicate a global sensation, such as morning, so that all colors inputted thereafter will be modified by the global sensation, or input a basic color, such as blue. In either case, menu driven user input information may include any number of human sensations relating to color for modifying the previously compounded color. In each case, the newly compounded color is displayed in a color display area on the screen. Thus formed, new colors may be named and stored to be retrieved at a later date. The menus on the display screen may be grouped according to basic decisions, basic colors, and compounding modifications according to human sensations, which latter may be subgrouped according to specific types of sensations such as mood, feeling, temperature, and the like.

Abstract: A frequency-multiplexed video signal is generated in which a color-under signal and a second under signal are linearly combined with at least partially overlapping frequency spectra to form a composite under signal for an FM luma signal. The frequency-multiplexed video signal is suited for recording on magnetic tape using helical scanning methods and for being played back from the magnetic tape using helical scanning methods. The second under signal is generated in such way that line-comb filtering can be used during playback to separate color-under signal and second under signal each from the composite signal despite their frequency spectra being at least partially overlapping in the composite signal.

Abstract: This invention provides a digital color encoder for digitizing color video signals. The encoder forms a digitized color video signal using logic function processing of the digitized luminance signal and color difference signals. The encoder provides an output signal equivalent to the luminance signal added to the color difference signals modulated by triangular wave functions and sampled at the sampling frequency. The sampling frequency is eight times the crominance subcarrier frequency. An analog video signal can easily be recovered from the digital video signal because the fundamental frequency of the triangular wave is easily separated from the higher order harmonics.

Abstract: An image signal processing device according to the present invention is a device for processing an image signal. The device is provided with a first differential amplifier for receiving a color-difference signal and a reference signal, a second differential amplifier for receiving a burst flag signal and the reference signal, and a modulator for receiving together signals outputted from the first and second differential amplifiers and modulating the received signals by using a carrier signal. Accordingly, it is possible to add the burst flag signal to the color-difference signal and modulate the obtained sum signal by means of a simple arrangement and without the need for complicated adjustment.

Abstract: A synchronous detector for demodulating and decoding a digital data signal modulated either according to a vestigial sideband or a quadrature amplitude modulation scheme is based upon the principle of recognizing that a vestigial sideband signal may be regarded and treated as an offset-keyed QAM signal. The detector comprises a tuner for tuning to a center frequency symmetrically displaced within the transmitted digital data signal frequency spectrum and a decoder circuit selectively operating to reconstruct the transmitted digital data stream according to the duration of a transmitted data symbol. A related method of demodulating and decoding a modulated digital data stream comprises analogous steps of tuning to a center carrier frequency and selectively switching between in phase and quadrature arms of the demodulator such that the switch resides in one position or the other for a duration equal to half the duration of a transmitted data symbol.

Abstract: A PAL encoder comprises phase converter, first and second low-pass filters, a burst signal adder, a chrominance subcarrier generator, and a modulator. The phase converter converts digital first and second color-difference signals into digital U-axis and V-axis signals. The first and second low-pass filters pass low-frequency components of the digital U-axis and V-axis signals to produce band-rejected U-axis and V-axis signals, respectively. The burst signal adder adds a predetermined burst signal to the band-rejected U-axis and V-axis signals to produce burst-added U-axis and V-axis signals, respectively. The chrominance subcarrier generator outputs digital sine and cosine signals of the chrominance subcarrier. The modulator multiplies the burst-added U-axis signal by the sine signal and the burst-added V-axis signal by the cosine signal and adds the multiplied results to produce a digital chroma signal.

Abstract: An RGB encoder includes a Y-matrix processor, a chrominance signal processor, a bandpass filter, a delay element, an OTA (operational transconductance amplifier) control signal generator and a mixer. The OTA bandpass filter has a plurality of operational transconductance amplifiers for bandpass-filtering the chrominance signal, wherein the passband is varied according to the transconductance of the operational transconductance amplifiers included therein. The OTA delay element has a plurality of operational transconductance amplifiers for receiving and delaying the luminance signal, wherein the delay time is varied according to the transconductance of the operational transconductance amplifiers included therein. The OTA control signal generator generates first and second control signals in accordance with an NTSC/PAL select signal.

Abstract: Disclosed is a method and apparatus for highly stably and accurately generating a PAL video signal by digital processing. The method and apparatus comprise generating a basic clock having a frequency which is 11.times.N times (N: an integer) as high as a horizontal synchronization frequency F.sub.H, producing digital data of orthogonal color subcarriers, color difference signals and a luminance signal respectively with the timing of the basic clock, multiplying the digital data D.sub.B-Y D.sub.R-Y of the color difference signals by the digital data Dsin and Dcos of the color subcarriers respectively to obtain digital data of two kinds of modulation signals, adding the digital data D.sub.Y+S of the luminance signal to the digital data of the two modulation signals, and effecting digital/analog conversion of the addition to provide the PAL video signal.

Abstract: A digital encoder for use in both NTSC and PAL systems includes a demultiplexer for separating a time-division color difference signal R-Y/B-Y into color difference signals R-Y and B-Y. The separated color difference signals R-Y and B-Y are converted by a sub-carrier frequency converter into a sub-carrier frequency, and a digital modulator determines levels and phases of the converted color difference signals. A burst generating circuit generates a burst signal after determining a level and phase of the burst signal, and a chroma encoder produces a chroma signal by mixing an output of the digital modulator with the burst signal.

Abstract: A video camera in which an output signal from a solid-state image sensor is converted into a corresponding digital signal at a horizontal reading cycle of the output signal, and the digital signal is digital-processed with a first predetermined clock (fs) synchronous with the reading cycle to provide a luminance signal and a color difference signal.