Abstract: The effect of the fluctuation of a signal that is caused by interference between the lines of an image display apparatus can be reduced. For this purpose, an image display apparatus comprises a plurality of lines, a plurality of display devices to which signals are respectively transmitted along the lines, and a signal circuit for generating the signals. The signal circuit outputs a signal having a duration, which is equivalent to a high-level period, that has been corrected in accordance with the length of a high-level period for a signal that is to be transmitted to an adjacent line of each line or in accordance with the number of times the level of a signal that is to be transmitted to an adjacent line is changed during the high-level period, or in order to reduce a change in luminance due to a level change for a signal that is to be transmitted to an adjacent line.

Abstract: A video signal input selector is subject to cross coupling between selectable video signals. The input selector comprises a video amplifier coupled to amplify a video signal selected from said selectable video signals. A controllable switch has first and second elements, the first element receives the selected video and is coupled to signal ground. The second element receives the selected video and is coupled to the amplifier. During a first condition the first element is controlled to be open circuit and the second element is controlled to be short circuit coupling the selected video signal to the video amplifier. In a second condition the first element is controlled to short circuit the selected video signal to the signal ground and the second element is controlled to be open circuit substantially inhibiting the selected video signal from coupling to the video amplifier.

Abstract: The method of gradation correction of input image data to be displayed on an image display apparatus converts to logarithmic data first characteristic values which represent the display characteristics inherent in the image display apparatus and second characteristic values which represent the desired gradation to be eventually realized with the image display apparatus, respectively, and optionally interpolating both the logarithmic data, constructs a gradation correction table based on both the logarithmic data of the first characteristic values and the logarithmic data of the second characteristic values and performs gradation correction on the input image data to the image display apparatus using the gradation correction table. The image display system displays on the image display apparatus the thus corrected image data on which the gradation correction is performed by implementing the method.

Abstract: A method for processing saturated video intervals in a video sequence. The method either removes or retains the saturated interval. If the interval is removed, the sequence is altered to accommodate the removal. The accommodation is either complete elimination, substitution of a derived interval, or substitution by repeating adjacent intervals. If the interval is retained, information is extracted while limiting the effects of the saturation. The interval can either be encoded with lower data rates, with increased data rates being applied to subsequent intervals, the temporal prediction encoding can be forced to a B interval, an I interval can be inserted, or the sequence restarted, or a coupled encoder decoder system can be set up that uses the same transform and clipping steps to limit the effects of saturation.

Abstract: A video signal decoder including a comb filter characterised by means for changing the operating mode of the filter progressively. Also, a video signal decoder including a comb filter characterised by means for adjusting continuously the degree of filtering performed by the filter. In one arrangement the decoder comprises an input filter and two signal multipliers wherein one of the multipliers is connected to receive a signal output by the input filter and the other multiplier is connected to receive a signal output by the comb filter wherein operation of the multipliers is mutually interdependent.

Abstract: A video recorder, includes: a filter for performing a comb-filtering operation and supplying a comb-filtered component of a video signal; controllable influencing apparatus for terminating the output of the comb-filtered component and activating instead, the propagation of the non-filtered component; transition detection apparatus for detecting a vertically extending transition and supplying characteristic information upon detection of such a transition; control information generating apparatus, arranged between the transtion detection apparatus and the influencing apparatus, for generating control information enabling the termination of the output of the comb-filtered component and the activation of the propagation of the non-filtered component for a period of time which is longer than possible by means of the characteristic information.

Abstract: An image processing apparatus detects a noise area in image data generated by decoding encoded data encoded by a frequency transform method and a lossy compression method. The image processing apparatus includes a motion detection unit for detecting motion in an area having at least one pixel in the image data, a deviation detection unit for detecting the deviation of the image motion in the area having at least one pixel, and a noise detection unit for detecting the noise area in accordance with the deviation of the image motion.

Abstract: The present invention provides a method and system for reducing flicker within an interlaced image. The method and system comprises identifying an area of the interlaced image where flicker needs to be reduced and adaptively adjusting a pattern of pixels derived from a non-interlaced spatial relationship of the interlaced image within the area based upon characteristics of the image. A flicker filter is provided which utilizes an adaptive technique whereby pixel-blending characteristics are constantly changed within the image depending on particular image attributes. It is unique in that high vertical resolution is maintained for detailed image content such as text and most graphics, while flicker is effectively reduced on image content that is flicker prone. The filter is based on psycho-visual studies and simulations performed by the company as well as numerous prior flicker filter implementations.

Abstract: A digital television receiver includes a filter for minimizing NTSC interference with a received signal having a constant symbol rate. An equalizer has two one symbol delays for each tap. A filtered and a non-filtered version of the received signal are applied to a multiplexer at the input of the equalizer, which is operated at twice the symbol rate. The outputs of the multipliers in the equalizer are combined and applied to a demultiplexer. The filtered and non-filtered equalized signals are compared and a selection as to which of the filtered or non-filtered received signals is to be processed is made based upon the comparison.

Abstract: An output signal of an 1H delaying circuit and a signal received from an input terminal are supplied to a subtracting circuit that forms a comb line filter. Thus, even if a dropout takes place in a luminance signal, not in a chroma signal, the chroma signal can be obtained from an output signal at intervals of 1H. When a dropout takes place, a limit operation of a feedback loop that forms a noise reduction circuit is stopped and the coefficient is increased. This process is performed with a dropout pulse that is delayed by 1H. Thus, the chroma signal can be obtained on the next line of the line having the dropout.

Abstract: Video signal processing apparatus includes a picture enhancement processor for processing a video signal to produce an enhanced video signal. The video signal includes a signal component representing video image data and another signal component representing non-image data such as vertical sync and a binary information component. The binary information component represents binary information that may occur, for example, during vertical blanking such as closed caption data, content advisory information (V-chip), or extended data services information. A control unit modifies the enhancement performed by the picture enhancement processor during intervals of the video signal that include non-image information. Modifying enhancement processing (e.g., reducing or disabling) during intervals that include the non-image information reduces degradation of the non-image information caused by the enhancement processing.

Abstract: The present invention relates in general to a digital-signal processing apparatus as well as a digital-signal processing method and, in particular, to a jitters removing apparatus as well as a jitters removing method. In the apparatus provided by the present invention, a TV signal received by a tuner or a video signal supplied by a VCR is fed to a moving-average correction circuit and a first FIFO circuit. In a correlation-value computing circuit, correlation between a carrier chrominance signal extracted by the moving-average correction and a carrier chrominance signal delayed by a second FIFO circuit by a predetermined time is found and a correlation value having a maximum absolute value is supplied to a quantization circuit. In the quanitization circuit, the quantization value is quantized to determine a class code. Then, coefficients for taps indicated by the class code are read out from a coefficient ROM unit and supplied to a linear first-order weighed-sum computing circuit.

Abstract: A noise suppression apparatus suppresses noise of a luminance signal, for example, at a fringe of area of reception in a television receiver. The noise suppression apparatus includes a tuner circuit, an intermediate frequency amplification circuit, a video detection/amplification circuit, an AGC detection/amplification circuit, an RF AGC circuit, a sound/chrominance signal separation circuit, a luminance signal processing circuit and a luminance signal noise suppression circuit.

Abstract: A video signal regenerator in color television comprises two video signal regeneration channels each of which has a video signal front detector (5-7) electrically connected to a driving input of a video holding sampler (1-3), while the third video signal regeneration channel has an input receiving a video signal of a pass-band wider than that of other video signals, which channel being analogous to the other regeneration channels and also comprising a video signal front detector (5-7) electrically connected to the driving input of the video holding sampler (1-3).

Abstract: The 25 Hz offset present in the subcarrier frequency of the PAL television standard causes residual and phase modified subcarrier to be left on the luminance signal, which can produce undesirable visual artifacts in the picture. In order to filter luminance therefore without loss of resolution, an adaptive luminance filtering process and structure are provided. Due to the wide range of sample frequencies that must be dealt with, there are e.g. three separate filters available selectable under software control depending on the particular video standard being filtered, i.e. for various of the of NTSC and PAL television standards. The adaptive notch filter is switched on during times of low video transitions and is by-passed during high video transitions, thus avoiding loss of resolution during the high video transitions.

Abstract: A constant luminance corrector for a television system determines brightness information that is discarded in the chrominance channels of an encoder, and adds it to the luminance channel of the encoder. Gamma-corrected luminance and chrominance component signals from a video source, such as a video camera, video tape recorder or the like, are input to the encoder which outputs an encoded luminance component signal and an encoded chrominance component signal that are combined to form a composite signal. The gamma-corrected component signals also are input to a luminance predictor circuit, or alternatively in lieu of the gamma-corrected chrominance component signals a coded chrominance signal and a discarded chrominance signal from the encoder may be input to the luminance predictor circuit. Likewise the encoded luminance component signal may be input to the luminance predictor circuit in lieu of the gamma-corrected luminance component signal.

Abstract: A color signal processor is provided for removing a leakage component from a harmonic wave of a color signal, which causes crosstalk on a screen when a video signal is reproduced from or recorded on a recording medium. To remove the leakage component of the color signal an additional main converter having the same function as that of an existing main converter, a 1H delay and a subtracter are added to a conventional color signal processor. A 180.degree. phase-inverted signal, generated by delaying a signal in the 1H delay, is subtracted from the signal output from the existing main converter, thereby outputting a pure color signal which does not include a leakage component due to the harmonic wave, thereby providing an excellent quality picture.

Abstract: A co-channel interference filter and a method for reducing co-channel interference for use in a television receiver. The television receiver receives a signal transmitted from a transmitter, the received signal having an encoded digital television signal component, a co-channel interference component, and a noise component, wherein the encoded digital television signal component is characterized as an N-level vestigial sideband (VSB) signal of Reed-Solomon (R-S) encoded, byte interleaved and trellis encoded symbols c.sub.k, i (for i=1 to 12), where N corresponds to a number of levels, and further wherein each symbol c.sub.k, i is derived from original symbol bits a.sub.k, i.sup.1 and a.sub.k, i.sup.2 (for i=1 to 12), respectively. The co-channel interference filter comprises a generator for generating a characteristic coefficient .alpha. in response to a received television signal, .alpha. being dependent upon an amount of the co-channel interference and noise components present in the received signal.

Abstract: When a video signal including a component modulated onto a subcarrier (such as a PAL signal) is subjected to a non-linear pre-emphasis known for MAC signals, with the object of reducing the effects of noise encountered in transmitting the composite signal through an f.m. channel, problems of noise and differential gain remain. These problems are overcome by subjecting the composite signal to a filtering step, before application of the non-linear processing, so as to filter out the subcarrier, the chrominance subcarrier in a PAL signal, and to compand the chrominance sidebands. Preferably a notch filter is used which has a notch shaped as a Gaussian curve.

Abstract: A solid state imaging apparatus includes two-dimensional frequency process which is applied to an output signal from each pixel of a progressive scan-type CCD. The CCD has an an arrangement of color separation filters without making carriers in the horizontal and vertical directions of the two-dimensional frequency to obtain chrominance signals with less moire in the horizontal and vertical directions of the two-dimensional frequency. A luminance signal with less moire in the horizontal and vertical directions of the two-dimensional frequency can be obtained by interpolating with the ratio of a chrominance signal with less moire.

Abstract: A first reproduced color under signal is delayed by one or two horizontal periods by a delay circuit, and this delayed second reproduced color under signal and the aforementioned first reproduced color under signal have their frequencies converted individually by first and second frequency converters into standard color signals. An oscillatory frequency signals of 2n of carriers for the aforementioned frequency conversions are divided to have the aforementioned carrier frequencies and to produce four carriers having phases of 0, 90, 180 and 270 degrees. These carriers are selectively fed to the first and second frequency converters by switches so that the two frequency-converted signals are subtracted or added in phase or in opposite phase to clear the noise (or crosstalk component), which is caused by the crosstalk between the tracks.

Abstract: An automatic gain control circuit for processing a reproduced color signal in a VCR which may include first and second feedback loops respectively positioned before and after a comb filter. In the first feedback loop, the color signal is amplified by a first variable gain amplifier and supplied to both a first burst detector and the comb filter via a frequency converter and a band-pass filter. The first burst detector detects the peak level of the burst signal included in the color signal and controls the gain of the first amplifier for stabilizing the level of the burst signal. The comb filter removes cross-talk components from the color signal and supplies an output signal to the second feedback loop. In the second feedback loop, the output signal is amplified by a second variable gain amplifier and supplied to a second burst detector.

Abstract: A color television system including an encoding device in which the chrominance and high-frequency luminance are sub-sampled in time. In the decoder, the high-frequency of the color television signal of the first and second fields are added thereby eliminating cross-luminance and the demodulated, low-frequency color difference signals are added thereby eliminating cross-color.

Abstract: A crosstalk detector for detecting the crosstalk of signals optically read from a recording medium having a plurality of tracks. A changeover circuit selects one of first and second signals generated by first and second oscillators. The amplitude of a signal of a predetermined center frequency is extracted from the selected signal and RF signal and that amplitude is compared with a control signal that inverts at every horizontal synchronizing period of a video signal demodulated from the RF signal.

Abstract: An input of a charge coupled device (CCD) delay element is an additional signal of a reproduced luminance signal and a reproduced chrominance signal, while an output of the CCD delay element is separated by an LPF and a BPF into a delayed luminance signal and a delayed chrominance signal, thereby constituting a comb filter by using the input signal before an addition and delayed/reproduced signals. Accordingly, it is unnecessary to provide a filter for limiting a band width, which is inserted into a main signal path. Furthermore, since it is possible to constitute a comb filter which does not narrow a signal band width of the reproduced luminance signal and the reproduced chrominance signal, there can be provided a comb filter for removing a cross-talk and noises and which does not narrow a signal band width of the luminance signal and the chrominance signal.

Abstract: Cross talk between luminance and chrominance is eliminated in a Weston Clean PAL codec by replacing the band pass filter used in a conventional codec with a high pass filter (L) and introducing a compensating low pass filter (X) into the chrominance path, the filters being chosen such that L=4F'*(1-F') and X(f)=(F'(f):(1-F'(f)) where F'=F(2fsc-f) and L is a low pass (5.5 MHz) filter 248 applied before transmission in the PAL channel.

Abstract: A chroma signal is emphasized then sub-sampled using a sampling offset differing by 90.degree. in four consecutive fields, then recorded on a recording medium. After reproduction from the recording medium, the phase of the reproduced chroma signal is corrected, and the phase corrected reproduced chroma signal is interpolated to increase its bandwidth and then non-linearly de-emphasized to reduce the noise contained therein. The interpolation is performed on adjacent pixels of four consecutive fields of the phase corrected reproduced chroma signal, and occurs before non-linear de-emphasis to reduce flicker.

Abstract: A comb filter separates a luminance signal and chrominance signal from a composite video signal, a phase calculation circuit calculates a phase delay of the chrominance signal, at least one delay circuit delays an output signal of the phase calculation circuit, a phase difference calculation circuit calculates a difference between an output signal of the phase calculation circuit and an output signal of the delay circuit, and a chrominance signal correction circuit attenuates the chrominance signal in response to an output signal of the phase difference calculation circuit. The chrominance signal having crosstalk from the luminance signal is suppressed to prevent the generation of cross color.

Abstract: A luminance/color signal separation apparatus comprising an analog/digital converter for converting a composite video signal inputted therein into a digital composite video signal, an adjacent signal detection circuit for detecting from the composite video signal from the analog/digital converter a target composite video signal from which luminance and color signals are to be separated and vertically and horizontally composite video signals, two-dimensional, horizontal and vertical pseudo median filtering circuits for outputting first to third luminance signals, respectively, a control signal generation circuit for generating horizontal and vertical control signals, a luminance signal selection circuit for selecting one of the first to third luminance signals in response to the horizontal and vertical control signals and outputting the selected luminance signal as the final luminance signal, a delay unit for delaying the target composite video signal by a predetermined time period for a timing matching with t

Abstract: A color signal processing device for processing a carrier chrominance signal is arranged to produce a first sampling signal by sampling the carrier chrominance signal according to a sampling clock signal synchronized with a reference phase of the carrier chrominance signal and a second sampling signal which is of a sampling phase opposite to that of the first sampling signal and to form baseband signals conforming to a color signal by using the first and second sampling signals. This arrangement enables the device to process the color signal without causing any signal deterioration that tends to result from DC fluctuations of the carrier chrominance signal.