Abstract: A wide aspect ratio television system includes memories for storing and recovering a video input signal in response to read and write clock pulses, respectively. Write clock pulses are deleted to compress edge regions of a wide aspect ratio input signal and read clock pulses are deleted to restore the signal to its original aspect ratio. The pattern of deleted pulses is altered on a line-by-line basis to reduce visible artifacts of signal decimation. Dual mode receivers include provisions for controlling edge blanking, interpolation and the pattern of clock pulses deleted as a function of received signals. Wide and standard aspect ratio images are displayed without altering the width of the display raster.
August 30, 1985
Date of Patent:
March 1, 1988
David L. Jose, Spyros W. Tsokas, Robert A. Dischert
Abstract: A selection circuit is connected between a display composed of unit picture elements arranged in a dot matrix and a vertical scanning circuit, the selection circuit effects the selection of odd or even lines in the display. The advantages offered by such an arrangement are elimination of the necessity of interlaced scanning in the scanning circuit itself, cutting the number of steps in half in the scanning circuit during interlaced scanning, increase in the margin in operating speed and elimination of limitations on circuit configuration, device construction and materials used.
Abstract: A color cathode ray tube has a fibre optic faceplate with a uniform phosphor layer on the inside and color elements on the outside, which may be color filters or color phosphors responsive to light from the inside phosphor layer. With this arrangement, the tube may be rugged and alignment problems as between the shadow mask and color elements are eliminated since the color element may be formed after the tube has been permanently assembled, the formation of the color elements being achieved utilizing light generated by the inside phosphor layer in response to irradiation thereof by the electron beams. The shadow mask is arranged so that the zones of the inside phosphor layer irradiated by the scanning electron beams each have an area which covers the ends of a plurality of the optical fibres.
Abstract: A small lightweight portable television transmitter having few components and operable with NTSC, PAL and SECAM systems. A one transistor video amplifier receives a gain controlled video signal and adjusts the d.c. level. Common mode noise rejection and sync pulse stretching is provided by a two transistor single ended output differential amplifier. The r.f. modulator combines and emitter follower and a one transistor mixer, with the r.f. applied to the collector and the modulating signals, including video and an audio modulated subcarrier, applied to the base. The transmitter has less than about 210 electrical components, weighs less than 1 kg when constructed with discrete components and substantially less when integrated into a hybrid circuit, yet provides 3 watts minimum peak power.
Abstract: A color imaging apparatus which produces a luminance signal and a plurality of chrominance signals in order to generate a composite color video signal which is capable of compensating a color reproduction characteristic in response to a variation of the color temperature of the incident light. A signal representative of the color temperature of the light is used to control the gain of the color difference signals and/or control the phase difference between a plurality of color subcarriers on which the chrominance signals are modulated. The color temperature signal can be produced from a white-balancing circuit or by a separate color temperature detector.
Abstract: An automatic brightness control device for preventing deterioration of image quality caused by frequency image muting to delete unnecessary images on a video screen which comprises an input terminal, a scaler for obtaining a mean value, first and second switching devices, and a sample and hold and integrating device all connected in the combination.
Abstract: A color image reader for decomposing two-color images into independent color components includes a color-separating mirror which is provided with a multi-layer interference filter on one of opposite major surfaces thereof. The other surface of the mirror serves as a reflection surface. Image light incident to the mirror is separated into two different color components which are then redirected to propagate in the same direction. The two color components respectively are focused to different line image sensors.
Abstract: Apparatus for checking or, respectively, correcting a color picture to be printed on a monitor, whereby reference colors stored for color checking by means of a coordinate acquisition means can be made visible in a reference color field at abitrary locations of the color picture.
Abstract: A DC restoration circuit includes a gate circuit, potential clamp capacitor, potential source circuit, detector circuit and mixing circuit. The gate circuit is responsive to both a first signal having a specific potential portion (pedestal level) and also to a gate signal generated at a given timing. The gate circuit detects the specific potential portion when the gate signal is generated, and provides a second signal corresponding to the detected specific potential portion. The potential clamp capacitor is used for clamping the potential of the second signal so as to provide a clamped potential. The potential source circuit is used for generating a level adjusting potential. The detector circuit is used for detecting the potential difference between the clamped potential and the level adjusting potential, and for providing a third signal corresponding to the potential difference.
Abstract: An input video signal representative of a scene is processed by carrying out a spatial transform operation on the input video signal so as to generate a transformed video signal. Concurrently, an input key signal representing the opacity of the scene and comprising a stream of digital data words is written into a key frame buffer. A first sequence of address words is generated, and a transform operation is carried out on the first sequence of address words so as to generate a second sequence of address words. The second sequence of address words is used to read digital data words from the key frame buffer so as to generate a first transformed key signal. The transform that was carried out on the first sequence of address words is such that the first transformed key signal is spatially transformed with respect to the input key signal in the same manner as the transformed video signal is spatially transformed with respect to the input video signal.
Abstract: In a television receiver with a digital processing system for processing display parameters, a CRT discharge detector produces a signal in response to discharge of the cathode ray tube of the television receiver, and a control-reset circuit employs a signal for generating one or more reset pulses for holding the registers of the signal processing circuits in their reset state for the duration of the cathode ray tube discharge. Following termination of the discharge, the reset signal is removed which allows the signal processing circuits to resume their normal function with unaltered data.
Abstract: An output video signal is derived from an input video signal by writing the input video signal into a frame buffer, generating a sequence of address words, modifying the sequence of address words, and using the modified sequence of address words to read the video signal from the frame buffer. The sequence of address words is modified by comparing each address word of the sequence with a reference word that defines a predetermined location of the scene represented by the input video signal, and combining each address word that defines a location of the input scene having a selected spatial relationship with the predetermined location with an offset word.
Abstract: To detect horizontally moving portions of a TV frame formed from two adjacent fields, the vertical local frequency at a vertical edge of the moving portion of the picture is measured with a narrow-band-pass filter circuit which is tuned to the local frequency of the comblike structure at ta vertical edge of staggered lines of the two fields of the frame. When such an edge structure is detected, the circuit delivers a detection signal.
Abstract: A high definition TV receiver includes a single frame memory arranged with three memory areas, three multiplexers, a movement detector, a half image interpolator and a control circuit to provide flicker-free video reproduction.
Abstract: A video display system is disclosed which has a video signal source for supplying the video signal of odd fields and even fields which are interlaced with each other, a first set of display cells for the odd fields, a second set of display for the even fields and arranged alternately with the first set of display cells in an interlaced fashion, a first circuit for supplying the video signal of the odd fields to the first set of display cells during the odd fields, and a second circuit for supplying the video signal of the even fields to the second set of display cells during the even fields. In this case, the first circuit includes a latching circuit for latching the video signal of the odd fields and supplying the latched signal to the first set of display cells during the even fields, and the second circuit includes a latching circuit for latching the video signal of the even fields and supplying the latched signal to the second set of display cells during the odd fields.
Abstract: A television composite video signal processing circuit has a readout circuit for repeatedly reading out a one-field composite video signal from a disk memory. A delay circuit delays the composite video signal from the readout circuit by 1/2 of a horizontal sync signal period H, and a pedestal clamping circuit sets the pedestal levels of the composite video signals from the delay circuit and the readout circuit to a predetermined level. A signal selector alternately supplies the composite video signals from the readout circuit and the delay circuit to the pedestal clamping circuit for every other field, and a peak level correction circuit corrects the peak level of the delayed video signal in the delayed composite video signal from the delay circuit.
Abstract: An apparatus and its method having a first input for receiving a video signal, and a second input for receiving a computer generated graphics signal. A proportioning circuit is included which algebraically adds a portion of the signal from one input, and an inversely proportional portion of the signal from the other input. The algebraically added signal portions are provided for video display. The apparatus may include a voltage limiting circuit for limiting the combined voltage of the added signal portions to less than a set level.
February 11, 1985
Date of Patent:
July 14, 1987
Lawrence C. Barnes, Robert G. Mankedick
Abstract: The distortion of an emitter-follower output stage of a video amplifier for driving a cathode of a picture display tube can be reduced without rendering a beam current control via this output stage impossible, by using a low-distortion buffer stage for producing a negative feedback signal at the output of the output stage. A higher follow rate for small signal variations can be obtained with the aid of a bias current or quiescent current which then is subtracted again from the current applied to an input of a beam measuring circuit which is controlled by the output stage.
Abstract: A superimposing apparatus comprises an obtaining circuit for obtaining a first positional information from a video signal including the first positional information, a comparing circuit for comparing a second positional information read out from a storage medium with the first positional information obtained in the obtaining circuit, a varying circuit for varying a read-out position on the storage medium according to a compared result in the comparing circuit so that the second positional information coincides with the first positional information, a character signal generating circuit for generating a character signal by reading out from the storage medium a character information corresponding to the second positional information when the first positional information and the second positional information coincide, and a mixed signal generating circuit for generating a mixed signal for a superimposed display by mixing to the video signal the character signal generated from the character signal generating circ
Abstract: In a picture-in-picture television receiver, the subpicture signal is A-D converted; the converted digital subpicture signal is latched in response a subpicture clock in synchronism with a subpicture synchronizing signal; the latched signal is latched again and stored in an image memory in response to a main picture synchronizing signal; and the latched signal is read from the image memory in synchronism with the main picture synchronizing signal, in order that the subpicture can stably be inserted in a predetermined area of the main picture by eliminating the unstable data duration during which variation in the subpicture signal is different for each bit signal thereof.