Abstract: A device that calculates a field difference by ROM and also a correlation between the calculated result and the delayed calculated result by ROM to detect one shot of flicker, and which uses a personal computer to examine the continued occurrence of the flicker-containing scene to make a final decision of the presence or absence of the flicker.

Abstract: A system for performing high efficiency coding of an image signal includes a differential signal generating section, a processing section, a supply section, a coefficient train outputting section, and a code assigning section. The differential signal generating section generates a differential image signal between a current image signal inputted thereto and a prediction image signal inputted thereto for the current image signal with respect to a target block. The current image signal and the differential image signal each include a plurality of blocks and the target block is one of the plurality of blocks. The processing section executes processing of a one-dimensional orthogonal transform and a quantization for an inputted objective image signal, with respect to the target block, to generate the processing result as quantization coefficients. The supply section supplies the processing section with the differential image signal as the objective image signal with respect to the target block.

Abstract: A digital audio signal demodulation circuit comprises a synchronous detection circuit (18) and a muting circuit (17) for muting the output from an interpolation circuit (16) using a synchronization lock signal generated from the synchronous detection circuit (18) when synchronization has been lost. The differential signal output from the interpolation circuit (16) is muted by the muting circuit (17) and thereafter integrated by an integration circuit (19). Thus, an audio signal with high sound quality can be demodulated without producing interruption noise even when synchronization has been lost or forcible muting is done.

Abstract: An audio signal demodulating circuit comprises a counter circuit (11) for detecting the number of samples for which interpolation is to be successively made by counting the output from an error correction circuit (2) and an AND circuit 10 for taking the logical product of the output from the counter circuit and the mute signal generated when synchronization has been lost. If interpolation is to be successively made for m (integer) or more, an audio differential signal is muted using a mute signal so as to remove the signal with greatly deteriorated audio quality. This can remove large audio distortion generated if interpolation is only successively made for error correction when errors successively occur for samples.

Abstract: In an audio signal demodulating circuit, an externally supplied reference clock signal is frequency-divided so that the frequency-divided clock signals are supplied to circuit units constituting the audio signal demodulating circuit as clock signals having lower frequencies. A logic circuit is provided to respond to a timing pulse generated synchronously with a video signal so as to set input data or clock signals supplied to the aforementioned circuit units to a low level or a high level during a time period other than the time period of an audio signal, whereby electric power consumption in the audio signal demodulating circuit is markedly reduced.

Abstract: A clamp system for television signal comprises a first clamp device for clamping to a clamp control voltage supplied from an external source by a horizontal clamp pulse and a second clamp device for controlling the DC potential of the television signal by adding the externally-supplied control voltage to an input television signal. The first clamp device is used during the period requiring an early clamp start, and the second clamp device is operated under normal conditions.

Abstract: An automatic gain control system for controlling a gain of an A/D converter automatically by controlling reference voltages of said A/D converter at the time of analog-to-digital conversion of a signal which signal being clamped by a clamp circuit to a clamp level which is set to a center level before entering said A/D converter, comprising a clamp level control circuit for detecting the clamp level from an output of said A/D converter to control the clamp level; a first A/D converter for digital-to-analog converting an output of said clamp level control circuit; an automatic clamp level control system.

Abstract: A television video signal control system is disclosed in which an amplitude control signal and a clamp voltage control signal digitally detected in the automatic gain control and clamp voltage control of a television signal receiver respectively are applied alternately to a single D/A converter. The resulting analog signal is sampled and held alternately at holding circuits corresponding to the two control signals. A D/A converter for converting the two control signals from digital to analog state is thus saved as compared with the prior art.

Abstract: Disclosed is an automatic gain control device which comprises: a first amplitude detection circuit for detecting an average amplitude value of a television video signal, a peak amplitude value of the same television video signal, or a value obtained by mixing the average amplitude value and the peak amplitude value with a predetermined mixing ratio; a second amplitude detection circuit for detecting an amplitude value of a vertical or horizontal synchronizing signal in the television video signal; an amplitude control circuit for controlling an amplitude of an input television video signal; a synchronization circuit for detecting a vertical synchronizing signal and a horizontal synchronizing signal in the television video signal so as to generate various pulses including a clock pulse synchronized with the input television video signal by controlling an oscillation frequency of an oscillation circuit; and a synchronization phase lock detection circuit for detecting whether the synchronization circuit has been

Abstract: A recording and reproducing apparatus is disclosed in whic

Abstract: There is provided an apparatus for compensating a contour of a television signal in a TV signal processing apparatus in which a predetermined control signal including a field interpolation control signal to control an interpolating method when reconstructing by an interpolation an image signal which was band compressed by the sub-Nyquist sampling is time sharingly multiplexed for a blanking period, wherein a signal of a still area processed by a still image system processing circuit and a signal of an animation area processed by an animation image system processing circuit are mixed by a mixing circuit every pixel, when the mixed signal is used as an input signal to the subsequent circuits, the OR of the binary signal of the movement amount and the field interpolation control signal transmitted from the transmission side is calculated, the still and animation areas are distinguished by the OR signal, and a contour is emphasized by a two-dimensional contour compensating circuit for the signal in the animation

Abstract: When the receiving system for a band-compression image signal receives a dropout signal representing a dropout portion of an image signal, an output of the third delay circuit of the temporal filter for motion detection processing, that is, motion information of an image signal, which precedes by one field, and a dropout signal activate the signal selection control circuit to produce an output signal for controlling the operation of the signal selection circuit, so that an output signal of the first delay circuit is selected for a static portion of an image, and an output signal of the dropout compensation circuit is selected for a moving portion of an image, so as to effect compensation control of the dropout portion of an image signal, thereby preventing deterioration of the quality of an image.

Abstract: The motion detection circuit is so constructed that an interframe difference signal is passed through a horizontal direction LPF and a vertical direction LPF in cascade connection, and the interframe difference signal thus obtained is divided by the value obtained by mixing an edge signal of an image and the image level signal of the image by a mixing circuit, thus providing a motion signal.

Abstract: In an apparatus for detecting movement of a television image in response to frame difference data corresponding to a difference between present frame data and previous frame data, a video signal is divided into a plurality of segmental areas for each frame, a pixel or picture element is selected to represent each of the segmental areas, frame difference data are produced for each of the segmental areas by calculating differences in the position or coordinates of a pixel representative of a segmental area of a previous frame from the respective picture element of the corresponding segmental area in the present frame, and each of the calculated differences smaller than a predetermined magnitude, and which would be characteristic of a stationary background portion of the television image, is omitted from the frame difference data. This is effective to improve the movement vector detection accuracy.

Abstract: A demodulator for regenerating and demodulating a carrier signal from a four-phase PSK received signal having a data symbol preamble and a fixed phase (one of four phases) of a particular time width using a synchronous detection type demodulating system (remodulation type demodulating system). The demodulator includes an orthogonal demodulating circuit and a remodulating circuit for regenerating a carrier signal which is the data signal during a preamble transmission period from a received modulated signal. The remodulating circuit includes a demodulator having an AFC circuit for detecting a frequency change using a narrow band filter, means for suppressing frequency changes of the four-phase PSK modulated signal received and means for rendering constant the frequency of the regenerated carrier signal passing through the narrow band filter.

Abstract: A high definition color television picture signal is unified by time-axis compressed integration (TCI) and the bandwidth thereof is extremely narrowed by dot-interlace subsampling. As a result, a narrow band transmission picture signal accompanied with a control signal adapted to the restoration of the received original picture signal, which is suitable for satellite broadcast, can be obtained through a comparatively simple arrangement. The received narrow band transmission picture signal can be restored by the interpolation adapted respectively to the stationary picture and the motion picture under control of the control signal or the picture-motional information detected from the received picture signal in combination with the control signal, so that the original high definition can be sufficiently maintained through comparatively simple receiving equipment.

Abstract: Image movement correction is provided in a field conversion television system by deriving simultaneously two fields of a selected number of lines from an original single field and vertically shifting one of the derived fields by 0.5 lines. A movement vector is determined for each field and movement correction is performed based on a current field and a preceding field, in the case of a moving object in the image. If no moving object is present linear approximation is employed to correct for motion caused by the field number conversion. Two memory systems are provided for the two simultaneous fields and also to selectively obtain specific horizontal lines of the current and preceding fields, relative to both simultaneous derived fields. Ultimate selection of a field for display is based upon the detected movement vector.

Abstract: In a bandwidth compressed transmission system in which a frequency band of a television signal of 2:1 interlace system is compressed, on an encoder side, by interfield offset subsampling at a first sampling frequency corresponding to a substantially upper limit frequency of the television signal and, after an output signal thus subsampled is applied to a LPF for passing a signal component having an aliased portion resulting from the interfield offset subsampling and having a cut-off frequency substantially equal to one half of the first sampling frequency, by interframe offset subsampling at a second sampling frequency lower than the first sampling frequency and higher than one half of the first sampling, so that a multiplexed subsampled transmission signal which does not include an aliased portion of reverse phase results from the interframe offset subsampling.

Abstract: The picture quality deterioration such as judder caused by TV frame number conversion can be mitigated by selecting either the stationary original picture signal or the motion-compensated interpolated picture signal based on the most adaptive motion vector corresponding to the smallest interframe difference between the original picture signal and the motion-compensated picture signals based on the motion vectors individually detected from divisional picture areas. The effect of this mitigation can be increased by weighting the detected motion vectors and by smoothing the contour between motion-compensated picture areas with the aid of filtering.

Abstract: A noise reduction apparatus for reducing noises contained in a television picture signal is realized by comprising a low pass filter for filtering out noise components together with higher frequency components of the picture signal, the latter being compensated thereafter in response to detection of edge portions of the picture, as well as realized by utilizing interframe correlation of the television picture signal for reducing random noise components together with interframe varying components caused by motion of the picture, the latter being compensated thereafter in response to detection of the motion of the picture, which motion is discriminated by interframe variation of a group of picture elements. As a result, the noise reduction of the picture signal can be efficiently attained without any deterioration of picture quality, which is conventionally accompanied therewith.