Patents Examined by John W. Shepperd
  • Patent number: 5005074
    Abstract: A multimode comb filter for comb filtering, e.g., NTSC and/or PAL video signals includes delay means for concurrently providing video signals representing three adjacent horizontal lines. First and second combining means coupled to the delay means provide alternate 1-H comb filter signals in both the NTSC and PAL modes. Control circuitry coupled to the delay means generates a control signal for adaptively selecting the one of the alternate 1-H comb filtered signals or appropriate proportions of both alternate 1-H comb filtered signals to form an output comb filtered signal.
    Type: Grant
    Filed: November 17, 1989
    Date of Patent: April 2, 1991
    Assignee: RCA Licensing Corporation
    Inventor: Stuart S. Perlman
  • Patent number: 5003393
    Abstract: The described control signal generator for processing a video signal is characterized by an addressable memory (PR1) whose addresses are associated with equally long time intervals of a video picture. The binary coded amplitude is stored at an address of the memory (PR1), which amplitude is to be assumed by the control signal (SS) generated by the control signal generator in the associated time interval. A counting unit (Z) which is clocked by a counter clock pulse (T) successively generates the addresses corresponding to consecutive time intervals of a video picture and being applied to the address inputs of the addressable memory (PR1). The frequency of the counter clock pulse (T) is chosen to be such that all addresses associated with a video picture are traversed during the time length of a video picture.
    Type: Grant
    Filed: March 14, 1989
    Date of Patent: March 26, 1991
    Assignee: U.S. Philips Corporation
    Inventor: Maximilian Riegel
  • Patent number: 5003390
    Abstract: The present invention is directed to the implementation of a reliable data communications system using the horizontal scan lines of video signals, and is particularly concerned with the minimization of problems which are caused as a result of false acquisition of horizontal scan lines and missed or dropped lines. In accordance with the present invention, a two-tier approach to receiving data transmitted via television signals is used. The two-tier approach includes a search mode and a lock mode. The present system operates on the principle that if a horizontal scan line (or lines) has been perfectly identified to contain data for successive fields of a video signal, then this scan line (or lines) can be presumed to be a valid data bearing scan line (or lines) in fields of the video signal yet to be received. The lock mode is then utilized to favor the retrieval of what would otherwise be missed or dropped horizontal scan lines were the system operating in the more restrictive search mode.
    Type: Grant
    Filed: March 26, 1990
    Date of Patent: March 26, 1991
    Assignees: PBSE Enterprises, Inc., EEG Enterprises, Inc.
    Inventors: Hermann J. Helgert, Mark S. Richer, William Posner
  • Patent number: 5003392
    Abstract: A video synchronizing signal having components of horizontal and vertical scan frequencies is supplied to both of first and second clocked circuit units. The first clocked circuit unit is clocked by a clock signal of a frequency substantially higher than the horizontal frequency component of the synchronizing signal and produces both horizontal frequency pulses and pulses having twice the horizontal frequency by means of a logic circuit which includes a counter. The latter pulses are used to clock the second clocked circuit unit which is supplied with pulses of horizontal frequency as well as with the synchronizing signal. By means of its logic circuits also including a counter, the second circuit unit produces pulses of vertical frequency, frame pulses of half the vertical frequency and a signal indicating whether the input synchronizing signal for both circuits conforms with a 625-line television standard or a 525-line standard.
    Type: Grant
    Filed: September 20, 1989
    Date of Patent: March 26, 1991
    Assignee: BTS Broadcast Television Systems GmbH
    Inventor: Gerhard Wischermann
  • Patent number: 5003404
    Abstract: A video camera includes in combination an image sensor, an image memory, a special effect circuit arranged to impart a special effect to the output signal of the image sensor by using the image memory, a selection circuit arranged to select either the output of the image sensor or that of the special effect circuit, and a control circuit which, in response to a pause of an image recording action, causes an image obtained when the pause is made to be stored in the image memory when the output of the special effect circuit is selected by the selection circuit.
    Type: Grant
    Filed: March 27, 1989
    Date of Patent: March 26, 1991
    Assignee: Canon Kabushiki Kaisha
    Inventors: Katsuji Yoshimura, Yoshihiro Nakatani, Tadayoshi Nakayama
  • Patent number: 5001563
    Abstract: In a picture signal processing circuit including an interpolation filter having a median filter (67) having a first input (63), a second input (69) and a third input (63) to which respective signals from picture elements of three positionally consecutive lines from a preceding and a present field of a line and field-sequentially assembled picture signal are applied, it has been found that a better result can be obtained for moving contours in the picture signal by taking a (weighted) average from these signals of the present field, and to take this average instead of or mixed with an output signal (Y') of the median filter (67).
    Type: Grant
    Filed: August 23, 1989
    Date of Patent: March 19, 1991
    Assignee: U.S. Philips Corporation
    Inventors: Terence Doyle, Martine Looymans
  • Patent number: 4999708
    Abstract: A synchronous separation circuit used in a television video circuit for generating a horizontal synchronizing signal and a vertical synchronizing signal from a composite synchronizing signal has: a unit for generating a clock signal used as a reference signal and having a frequency higher than the frequency of the horizontal synchronizing signal; a unit for counting the clock signal from a front edge of a pulse contained in the composite synchronizing signal; a unit for obtaining a horizontal synchronous separation and for determining a counting term and outputting the horizontal synchronizing signal after the counting unit counts from the front edge of the horizontal synchronizing signal to a predetermined number; and a unit for obtaining a vertical synchronous separation and for latching the composite synchronizing signal based on an output of the counting unit, separate the vertical synchronizing signal from the composite synchronizing signal.
    Type: Grant
    Filed: January 23, 1989
    Date of Patent: March 12, 1991
    Assignee: Fujitsu Limited
    Inventors: Tetsuo Aoki, Fumitaka Asami
  • Patent number: 4999701
    Abstract: A system for generating high definition television signals. An augmentation signal is provided for supporting the transmission of additional panel information, increasing the aspect ratio of an NTSC compatible main television signal component. Line differential information, as well as high frequency luminance and high frequency chrominance are transmitted in the augmentation signal super line time interval without frequency interleaving components. The high definition augmentation signal is derived by subsampling the high definition image produced by an HDTV source along the diagonal direction of its two dimensional frequency spectrum. The horizontal frequency bandwidth of the HDTV image is perserved without an objectionable loss of resolution to the human visual system.
    Type: Grant
    Filed: July 10, 1989
    Date of Patent: March 12, 1991
    Assignee: North American Philips Corporation
    Inventors: Alan P. Cavallerano, Mikhail Tsinberg, Karl Wittig
  • Patent number: 4999709
    Abstract: Apparatus for superimposing graphic title image signals onto an input video signal to produce a video picture having graphics, such as title images, superimposed thereon. Graphic title image data is written into a memory and subsequently is read out under the control of an address generator whose read-out addresses are shifted at a given repetition rate to change the positioning of the graphic title image data relative to the video signal, thereby producing a scrolling effect of the graphics across an image plane.
    Type: Grant
    Filed: January 19, 1989
    Date of Patent: March 12, 1991
    Assignee: Sony Corporation
    Inventors: Hiroshi Yamazaki, Sakae Okazaki
  • Patent number: 4998162
    Abstract: In a camera having a lens for focussing incident light onto a light reception surface of a pick-up so that the latter outputs a camera signal, a stop for limiting the amount of the incident light, and a variable gain amplifier for correcting the level of the camera signal; there is provided a control circuit which controls a focus of the lens, the stop and a gain of the variable gain amplifier on the basis of the output of the variable gain amplifier, thereby simplifying the construction of the camera as a whole.
    Type: Grant
    Filed: August 15, 1989
    Date of Patent: March 5, 1991
    Assignee: Sony Corporation
    Inventors: Toshiharu Kondo, Akihiro Kikuchi, Takashi Kohashi
  • Patent number: 4996596
    Abstract: A circuit for providing a signal phase locked to a horizontal synchronization signal included in a received video signal includes a first PLL loop (16, 44, 46; 16, 46', 204) and a second PLL or AFC loop (26, 44, 46; 26, 44, 46', 204). The first PPL loop has a plurality of lock ranges. The second PLL or AFC loop, which has an output characteristic with a single S curve, has one lock range large in width. The second PLL or AFC loop is supplied with a horizontal synchronization signal separated in a synchronization separating circuit via a bandpass filter. The first PLL loop is directly supplied with a horizontal synchronization signal extracted in the synchronization separating circuit. The first PLL loop shares a voltage controlled oscillator (46; 46') and a frequency divider (46; 204) with the second PLL loop or AFC loop.
    Type: Grant
    Filed: September 1, 1989
    Date of Patent: February 26, 1991
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Yoshichika Hirao, Nobukazu Hosoya
  • Patent number: 4994899
    Abstract: In a Multiplexed Analog Component (MAC) color television transmission system in which the MAC signal is to be converted at the receiver to a composite color television signal having a 227.5 f.sub.H color subcarrier, frequency-generation equipment required at the receiver is simplified, and bandwidth is extended, by selecting the various frequencies in accordance with the following relationship:f.sub.0 =3f.sub.1 =3f.sub.2 =2f.sub.4 =1365k f.sub.Hwhere:f.sub.0 is the master clock frequency,f.sub.1 is the luminance samping frequency,f.sub.2 is the chrominance sampling frequency,f.sub.4 is the MAC sampling frequency,f.sub.H is the horizontal line frequency, andk is a positive integer greater than 2.f.sub.3 is the data clock frequency which is independent of k and remains fixed at its present value.For MAC receivers designed for C, D or C/2 standards, the relationship becomesf.sub.0 =3f.sub.1 =6f.sub.2 =2f.sub.4 =1296k f.sub.Hwhere the symbols have the same meaning as above. f.sub.
    Type: Grant
    Filed: March 23, 1988
    Date of Patent: February 19, 1991
    Assignee: Scientific Atlanta, Inc.
    Inventor: Charles W. Rhodes
  • Patent number: 4994900
    Abstract: In normal reproduction, a switch circuit (11) is set to select an output signal of an A/D converter (1). Consequently, a movement adaptation type YC separating circuit is formed, whereby a luminance signal and a chrominance signal are separated. When a control signal is outputted from a control signal generating circuit (12) in response to an instruction of still picture reproduction, the switch circuit (11) selects an output signal of the last output terminal of delay means formed by line memory (2) or frame memory (3) and inputs the selected signal to the first input terminal of the delay means. As a result, in still picture reproduction, a circulating circuit where the inputted composite video signal circulates in the delay means is formed and a luminance signal and a chrominance signal are separated based on a plurality of composite video signals having different delay times obtained from the circulating circuit.
    Type: Grant
    Filed: November 6, 1989
    Date of Patent: February 19, 1991
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Masami Ebara, Hajime Mizugami, Tadashi Amino
  • Patent number: 4992856
    Abstract: A color television decoder is provided for separating chrominance signals from a color video signal. The decoder has a variable two dimensional finite impulse response filter, comprising delay lines which provide signals representing an array of picture points around the picture point being imaged, and a variable combiner which linearly combines the signals with variable coefficients. A picture analyzer analyzes the picture and controls the variable coefficients so as to control the filter response to separate the chrominance signal. The luminance signal may be separated by subtracting the chrominance signal from the delayed color video signal.
    Type: Grant
    Filed: July 10, 1989
    Date of Patent: February 12, 1991
    Assignee: Vistek Electronics Limited
    Inventor: Roger N. Robinson
  • Patent number: 4992852
    Abstract: A circuit for producing a chroma signal which includes both of a first and a second color difference signal on each of scanning lines in response to a line-sequential color difference signal in which a first and a second color difference signal appear alternately on consecutive scanning lines. A carrier generator generates a first and a second color subcarrier which are different in phase from each other in synchronism with the line-sequential color difference signal. The first color subcarrier is subjected to balanced modulation at a first modulator which uses the first color difference signal for the modulation while the second color subcarrier is subjected to balanced modulation at a second modulator which uses the second color difference signal. The outputs of the first and second modulators are added together by a first adder. A delay circuit is provided for delaying an output of the first adder by a period of time which is substantially equal to one horizontal scanning period.
    Type: Grant
    Filed: October 3, 1988
    Date of Patent: February 12, 1991
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Ikuhisa Sekizawa, Kazuo Okada
  • Patent number: 4992853
    Abstract: A system for transmitting an interlaced source signal, for example 1050 lines, 2:1 interlaced, via a MAC signal, and decoding and receiving same.
    Type: Grant
    Filed: November 14, 1988
    Date of Patent: February 12, 1991
    Assignee: North American Philips Corporation
    Inventor: Alan P. Cavallerano
  • Patent number: 4991019
    Abstract: In a digital video signal processing system disclosed, a plurality of programmable processor units (21(01) to 21(16)) each receive two different video signals, process the video signal in accordance with a program, and output the result of the signal processing. A network section (20) receives the output data signals from the plurality of programmable processor units (21(01) to 21(16)) and a plurality of video signals (A1, A2) from exterior, and supplies the received signals to the plurality of programmable processor units (21(01) to 21(16)), and leadouts any one of the produced signals or input video signals. The network section (20) is capable of freely altering a connection pattern of the plurality of programmable processor units (21(01) to 21(16)). The programmable processor units (21(01) to 21(16)) may have signal processing functions as defined by applied programs.
    Type: Grant
    Filed: February 9, 1989
    Date of Patent: February 5, 1991
    Assignees: Nippon Hoso Kyokai, Kabushiki Kaisha Toshiba
    Inventors: Kazumasa Enami, Nobuyuki Yagi, Ryoichi Yajima, Kiyomasa Kanai, Shigemi Mikami, Nobuyuki Sasaki, Kazuhiro Harukawa, Kouji Hoshino, Yuji Konno
  • Patent number: 4991015
    Abstract: A method and circuit arrangement identifies the presence or absence of known frequencies in an input signal composed of a plurality of frequencies, whereby a frequency generator controlled by a reference frequency generates four switch signals having frequencies dependent upon the frequency to be identified and having a phase difference of 90.degree. and respectively one switch signal is mixed with the input signal in a respective mixer. The respective mixer products of two mixers are additively combined and are filtered through a respective filter for filtering AC components out, and the DC voltage component contained in the respective mixer product given the presence of the known frequency is evaluated with respect to the amplitude.
    Type: Grant
    Filed: July 5, 1990
    Date of Patent: February 5, 1991
    Assignee: Siemens Aktiengesellschaft
    Inventor: Richard Stepp
  • Patent number: 4989091
    Abstract: A high definition B-MAC television signal transmission system comprises a scan converter and a signal pre-processor for accepting signals in various high definition formats. In particular, an 1125 line or 1050 line to 525 line scan converter is required due to the preponderance of at least 1125 line and to some extent 1050 line 60 Hertz field rate format high definition television studio equipment. The scan converter includes circuitry for converting from horizontal to vertical scan format via first and second field stores. A phase shift transversal filter spatially shifts every sample of each field by 1/4 line. In alternate fields, the direction of spatial shifting reverses. For an interlace output, alternate line samples are discarded or for a sequential scan output, all samples are used. The output of the transversal filter is scan converted to reassume a horizontal scan format.
    Type: Grant
    Filed: April 28, 1989
    Date of Patent: January 29, 1991
    Assignee: Scientific-Atlanta, Inc.
    Inventor: Keith Lucas
  • Patent number: 4989073
    Abstract: At the input to a video signal time base corrector, the phase error is sampled during each burst interval and is used to control the operation of an analog-to-digital convertor to compensate for phase errors at the start of each line. Progressive phase errors are predicted during each line and compensated. Any residual phase error at the start of a line is detected and applied to a phase error compensator for eliminating the residual phase error. The residual phase error and the video signal are processed through separate signal paths, and the frequency and phase characteristics of the residual phase error path are adjusted to those of the video signal path.
    Type: Grant
    Filed: December 28, 1988
    Date of Patent: January 29, 1991
    Assignee: Ampex Corporation
    Inventor: Steven D. Wagner