A/d Converters Patents (Class 348/572)
  • Publication number: 20090086104
    Abstract: In a multimedia SOC that includes a plurality of jack sense modules coupled to the plurality of video output pins, a processing module functions to: enable one or more of the plurality of jack sense modules to determine a video connection to the SOC, enable a video decoder in a first mode when the video connection is of a first type, and enable the video decoder in a second mode when the video connection is of a second type
    Type: Application
    Filed: September 28, 2007
    Publication date: April 2, 2009
    Inventor: Matthew D. Felder
  • Patent number: 7505055
    Abstract: A method, apparatus, and system for determining a horizontal resolution and a phase of an analog video signal arranged to display a number of scan lines each formed of a number of pixels is described. A number of initialization values are set where at least one of the initialization values is a current horizontal resolution and then a difference value for each immediately adjacent ones of the pixels is determined. Next, an edge flag value based upon the difference value is stored in at least one of a number of accumulators such that when at least one of the accumulators has a stored edge flag value that is substantially greater than those stored edge flag values in the other accumulators, then the horizontal resolution is set to the current resolution.
    Type: Grant
    Filed: December 21, 2004
    Date of Patent: March 17, 2009
    Assignee: Genesis Microchip Inc.
    Inventor: Greg Neal
  • Patent number: 7502076
    Abstract: A method and apparatus for a digital video display. A digital display device receives an analog signal representing an image formed of pixels in video lines and a signal containing a synchronization waveform for the image. An analog-to-digital converter (ADC) receives the analog signal and converts it to a sampled digital waveform. A phase-locked loop including a programmable frequency divider controls the sampling time for the ADC. The programmable frequency divider is controlled by a dividing-ratio algorithm that selects a dividing ratio, measures the number of pixels in a video line using the dividing ratio, and recomputes the dividing ratio by multiplying the selected dividing ratio by the expected number of pixels in a video line and dividing by the measured number of pixels. The sampling phase for the ADC is selected by a sampling-phase control algorithm that minimizes a function representative of the flatness of the sampled digital waveform.
    Type: Grant
    Filed: July 21, 2005
    Date of Patent: March 10, 2009
    Assignee: Texas Instruments Incorporated
    Inventors: Liming Xiu, Wen Li, Xiaopeng Li
  • Publication number: 20090059075
    Abstract: A TV signal determining system utilized for determining a type of a TV signal includes: a detection unit, for utilizing a predetermined profile to detect if the TV signal has a signal segment corresponding to the predetermined profile to generate a detection result signal; and a determining unit, coupled to the detection unit, for determining the type of the TV signal according to the detection result signal. A TV signal processing system utilizing the TV signal determining system and a related method are also disclosed.
    Type: Application
    Filed: September 4, 2007
    Publication date: March 5, 2009
    Inventor: Hung-Shih Lin
  • Publication number: 20090059012
    Abstract: A programmable digital black level calibration circuit comprises a combining circuit, a digital programmable gain amplifier (PGA), and a black level feedback circuit. The combining circuit combines a digital image signal for optical black (OB) pixels and a feedback signal and outputs a digital PGA input signal. The PGA amplifies the digital PGA input signal by a PGA gain value and outputs a digital PGA output signal. The black level feedback circuit receives the digital PGA output signal and a target black level and in response outputs the feedback signal such that a black level of the OB pixels is calibrated with respect to the target black level. The programmable digital black level calibration circuit calibrates the black level in pure digital domain using signed data buses. The target black level is adjustable to a desired positive or negative value independent from the PGA gain value.
    Type: Application
    Filed: October 27, 2008
    Publication date: March 5, 2009
    Inventors: Yasu Noguchi, Kazuya Sasaki
  • Patent number: 7495708
    Abstract: The present invention proposes a method for generating a digital video signal from an analog input video signal, which prevents picture jitter in the digitized video signal when the analog input video signal is not in complete conformity with a standard. According to the invention, the method includes the steps of: detecting the type of signal source; in case the type of signal source is a non-standard type, detecting the existence of an error state; converting the analog input video signal to a digital video signal; in case an error state exists, replacing an error prone part of the digitized video signal with a substitute signal part; and in case the type of signal source is a standard type or no error state exists, keeping the digitized video signal unchanged.
    Type: Grant
    Filed: July 13, 2005
    Date of Patent: February 24, 2009
    Assignee: Thomson Licensing
    Inventors: Chee Lam Tan, Hua Li, Frank Dumont
  • Publication number: 20090033778
    Abstract: Disclosed herein is a camera system and camera controller having a modularized design. Camera control functions within the controller are distributed among a number of modules, each module performing a component task of controlling a camera. Individual modules can perform tasks such as generating clock signals, digitizing an analog video signal, and providing multiplexed digital video output. Modules communicate with each other over a common bus sufficient to carry the signals necessary to control the camera. The system implements a RAM-based digital sequencer that provides the capability of loading bit patterns into memory and using these patterns to generate waveforms for clocking a CCD. Clock and readout sequences can be composed in a high level language, compiled and uploaded into the controller. Adjustable clamp and sample signal delays used in digitizing an analog video signal provide the capability to optimize the performance of the system in a given application.
    Type: Application
    Filed: October 3, 2008
    Publication date: February 5, 2009
    Applicant: SciMeasure Analytical Systems, Inc.
    Inventors: Charles A. Bleau, Raymond C. DuVarney
  • Patent number: 7486336
    Abstract: An analog-to-digital converting system for converting a composite video signal into a digital signal according to a synchronized clock. The analog-to-digital converting system includes an analog-to-digital converter (ADC), a color burst phase estimator and a phase-locked loop (PLL). The ADC converts the composite video signal to the digital signal according to the synchronized clock, wherein the synchronized clock is synchronized to a frequency of a color burst of a chrominance signal of the composite video signal. The color burst phase estimator, coupled to the ADC, estimates the phase of the color burst carried on the composite video signal. The PLL, coupled to the color burst phase estimator, generates the synchronized clock according to the phase of the color burst estimated by the color burst phase estimator.
    Type: Grant
    Filed: October 6, 2005
    Date of Patent: February 3, 2009
    Assignee: MStar Semiconductor, Inc.
    Inventors: Ke-Chiang Huang, Ta-Chan Kao, Sterling Smith
  • Publication number: 20090027556
    Abstract: Disclosed herein is a camera system and camera controller having a modularized design. Camera control functions within the controller are distributed among a number of modules, each module performing a component task of controlling a camera. Individual modules can perform tasks such as generating clock signals, digitizing an analog video signal, and providing multiplexed digital video output. Modules communicate with each other over a common bus sufficient to carry the signals necessary to control the camera. The system implements a RAM-based digital sequencer that provides the capability of loading bit patterns into memory and using these patterns to generate waveforms for clocking a CCD. Clock and readout sequences can be composed in a high level language, compiled and uploaded into the controller. Adjustable clamp and sample signal delays used in digitizing an analog video signal provide the capability to optimize the performance of the system in a given application.
    Type: Application
    Filed: October 3, 2008
    Publication date: January 29, 2009
    Applicant: SciMeasure Analytical Systems, Inc.
    Inventors: Charles A. Bleau, Raymond C. Lilburn
  • Publication number: 20090027553
    Abstract: An image signal processor and a method for processing an image signal thereof are disclosed. When the image signal processor executes an automatic chroma gain control (ACC), the image signal processor adjusts a variable rate of ACC gain according to a size of an input color signal to reduce a time for processing the ACC. Even if a difference between the size of the input color signal and the size of a reference color signal is large, the ACC is rapidly processed. As a result, transient phenomenon disappears from a screen.
    Type: Application
    Filed: January 17, 2008
    Publication date: January 29, 2009
    Applicant: Samsung Electronics Co., Ltd
    Inventor: Hye-joung Park
  • Publication number: 20090027490
    Abstract: This is an endoscope apparatus which has an endoscope which picks up an image of a sample using a solid state image pickup element and outputs an image pickup signal, and a processor which processes the above-mentioned image pickup signal, generates HDTV and SDTV serial digital video signals, switches one side of those selectively, and performs a serial output, in which the serial digital video signal switched selectively by the above-mentioned processor is output through a first connector, the above-mentioned processor is equipped with a discrimination signal generating section which is linked with selection switching of the above-mentioned HDTV or SDTV serial digital video signal to generate an HDTV/SDTV discrimination signal which can discriminate the above-mentioned HDTV or SDTV serial digital video signal, and the discrimination signal is output through a second connector different from the above-mentioned first connector.
    Type: Application
    Filed: June 2, 2006
    Publication date: January 29, 2009
    Applicant: OLYMPUS MEDICAL SYSTEMS CORP.
    Inventors: Tsutomu Hirai, Tomoki Iwasaki, Kazumasa Takahashi, Hidenori Hashimoto, Akihiko Mochida, Katsuyuki Saito, Makoto Tsunakawa, Kentaro Hase, Kotaro Ogasawara, Tadao Eto, Akihito Kawamura, Shin Liu, Shoichi Amano, Jun Konishi
  • Publication number: 20090021643
    Abstract: A digital television chip having a reduced layout size is disclosed, comprising a multiplexer, and first and second converting units. The multiplexer, according to a control signal, outputs one of S-video signals SY and SC to the first converting unit, outputs the other of the S-video signals SY and SC to the second converting unit, outputs one of Tuner CVBS signals VIF and SIF to the first converting unit, outputs the other of the Tuner CVBS signals VIF and SIF to the second converting unit, or outputs a CVBS Line-in Video signal to one of the first and second converting units, for reducing the size of the chip. The first converting unit converts one of the S-video signals SY and SC, one of the Tuner CVBS signals VIF and SIF, or the CVBS Line-in Video signal into a first digital signal for signal processing. The second converting unit converts one of the S-video signals SY and SC, one of the Tuner CVBS signals VIF and SIF, or the CVBS Line-in Video signal into a second digital signal for signal processing.
    Type: Application
    Filed: May 12, 2008
    Publication date: January 22, 2009
    Applicant: MEDIATEK INC.
    Inventors: Kang-Wei Hsueh, Ya-Lun Yang, Hung-Sung Li
  • Patent number: 7480012
    Abstract: The invention relates to a multiplexed video digitization system and method. The system includes a plurality of analog video signals, a multiplexer to select one of the plurality of analog video signals, and an analog-to-digital converter to convert the selected analog video signal into a digital video signal. The plurality of analog video signals may include component video signals, red, green, and blue signals, or s-video signals. The multiplexer may include control logic to select the one of the plurality of analog video signals. The system may include a plurality of sample and hold circuits to insure time aligned sampling of the corresponding plurality of video signals.
    Type: Grant
    Filed: February 24, 2005
    Date of Patent: January 20, 2009
    Assignee: Pixelworks, Inc.
    Inventor: Robert Y. Greenberg
  • Patent number: 7471339
    Abstract: A high-speed video signal processing system, which includes a reception end for receiving analog signals; a plurality of analog to digital converters coupled to the reception end for converting analog signals received from the reception end to digital signals according to control signals; and an interleaving controller coupled to the plurality of analog to digital converters for generating the control signals to selectively enable the plurality of analog to digital converters according to a predetermined sequence.
    Type: Grant
    Filed: May 24, 2005
    Date of Patent: December 30, 2008
    Assignee: MStar Semiconductor, Inc.
    Inventors: Sterling Smith, Chia-Ming Yang, Chih-Shiun Lu
  • Patent number: 7471340
    Abstract: A video quality adaptive variable-rate buffering method and system for stabilizing a sampled video signal reduces the buffer size required to compensate for line-to-line variations in an unstable video source. A video signal is sampled at a predetermined rate and decimated by a selectable decimation factor prior to buffering. By selecting different decimation factors, the effective length of the buffer is changed from short duration for stable input signals and to longer duration for unstable input signals. A video signal quality detector is employed to provide a selection input that adjusts the decimation factor and also the loop bandwidth of a clock generator that provides the output clock for the buffer, which is generated from the input signal via a phase-lock loop (PLL). The operation of the system automatically varies from highly responsive for stable video input signals to less responsive for unstable video input signals, providing improved stability in the video output.
    Type: Grant
    Filed: March 24, 2005
    Date of Patent: December 30, 2008
    Assignee: Cirrus Logic, Inc.
    Inventors: Ahsan Chowdhury, Rahul Singh, John L. Melanson, James A. Antone
  • Publication number: 20080316361
    Abstract: A picture signal processing device includes an A/D conversion unit configured to convert an input analog picture signal into a digital picture signal; an automatic image correction unit configured to correct the digital picture signal from the A/D conversion unit; a narrowing-down unit configured to narrow down possible formats of the analog picture signal based on horizontal and vertical signal frequencies of the analog picture signal, horizontal and vertical synchronizing signal polarities and vertical line count; and an identification unit configured to identify the format of the input analog picture signal from among a plurality of narrowed-down candidate signal formats.
    Type: Application
    Filed: June 20, 2008
    Publication date: December 25, 2008
    Inventors: Yoshinori ITO, Tetsuji MORITA, Kosuke YAMAMOTO
  • Patent number: 7460177
    Abstract: A signal processing device of the present invention includes: an input unit which inputs an analog video signal; an A/D converter which converts the analog video signal to a digital video signal; a detecting unit which detects a level in a predetermined period of the digital video signal output from the A/D converter; a difference output unit which detects a difference between the level detected by the detecting unit and a desired value; a modulating unit which performs sigma-delta modulation on an output from the difference output unit; and a clamping unit which performs a clamping process on the analog video signal input by the input unit based on an output from the modulating unit and which outputs the clamped analog video signal to the A/D converter.
    Type: Grant
    Filed: June 9, 2005
    Date of Patent: December 2, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventor: Hiroya Miura
  • Patent number: 7456903
    Abstract: A video signal processing circuit is supplied with an analog composite video signal formed by combining at least a luminance signal with a sync signal, and processes the analog composite video signal. The video signal processing circuit has an analog filter which removes high-frequency components from the analog composite video signal, a sync separation circuit which separates a sync signal from an output signal from the analog filter, an AD converter which performs AD conversion on the analog composite video signal, and a digital video signal processing circuit which performs predetermined video signal processing on the composite video signal digitized by the AD converter, by using the sync signal obtained by the sync separation circuit.
    Type: Grant
    Filed: October 4, 2005
    Date of Patent: November 25, 2008
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Ikuo Osawa, Yoshifumi Yoshida, Hiroyuki Ebinuma, Toru Okada
  • Publication number: 20080266457
    Abstract: A scene change detection device according to the present invention includes an audio information determination part detecting silent state of audio signal to output silence detection time information, an image information determination part detecting brightness change or decreased level of brightness of an image in image signal to store scene change time information indicating time detecting the brightness change or decreased level of brightness, a scene change candidate point detector outputting scene change candidate time based on the silence detection time information and the scene change time information, and an output determination part outputting scene change detection information based on time difference between successive first scene change candidate time and second scene change candidate time and a detection maximum value.
    Type: Application
    Filed: April 24, 2008
    Publication date: October 30, 2008
    Applicant: NEC ELECTRONICS CORPORATION
    Inventor: Yasuaki Sasakura
  • Publication number: 20080259214
    Abstract: Provided is a video signal processing device that can reduce power consumption within an analog signal processing unit not only during an invalid frame period of a video signal but also during a blanking period within a valid frame period, thus enabling further reduction of the power consumption. The video signal processing device that performs signal processing on an analog video signal inputted from outside includes: an analog signal processing unit including: a CDS/AGC unit that samples the analog video signal and amplifies the sampled analog video signal; and an AD converting unit that converts the resulting analog video signal from analog to digital, and a timing control unit that controls the analog signal processing unit to switch between an operating mode and a standby mode.
    Type: Application
    Filed: April 15, 2008
    Publication date: October 23, 2008
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Keiichi TSUMURA, Shinji YAMAMOTO, Kenji NAKAMURA
  • Publication number: 20080252787
    Abstract: A first clamping unit clamps a base voltage of an input image signal to a predetermined reference voltage. A sampling-and-holding unit samples and holds the image signal after clamping or a reference signal that becomes the base voltage of the image signal. An amplifying unit amplifies the image signal sampled and held by the sampling-and-holding unit. An analog-to-digital converting unit converts the image signal after amplification into a digital image signal. A second clamping unit clamps the reference signal to a predetermined voltage.
    Type: Application
    Filed: April 8, 2008
    Publication date: October 16, 2008
    Inventors: Masamoto Nakazawa, Tohru Kanno
  • Patent number: 7432843
    Abstract: A signal is temporally compressively sampled. A plurality of analog to digital converters are assembled to sample the signal. Each analog to digital converter of the plurality of analog to digital converters is configured to sample the signal at a time step determined by a temporal sampling function. The signal is sampled over a period of time using the plurality of analog to digital converters. Each analog to digital converter of the plurality of analog to digital converters produces a measurement resulting in a number of measurements for the period of time. A number of estimated signal values are calculated from the number of measurements and the temporal sampling function. The temporal sampling function is selected so that the number of measurements is less than the number of estimated signal values.
    Type: Grant
    Filed: July 31, 2007
    Date of Patent: October 7, 2008
    Assignee: Duke University
    Inventors: David J. Brady, Nikos Pitsianis, Xiaobai Sun, Prasant Potuluri
  • Publication number: 20080225175
    Abstract: Various embodiments are described herein for a universal television receiver that is capable of processing television channel signals, that are transmitted according to a variety of broadcast standards, to provide video and audio information for a desired television channel signal. The processing includes producing a coarse channel signal that includes a desired television channel signal and then applying resampling techniques to adjust a normalized bandwidth of the desired television channel signal to generally correspond to the normalized passband of a main filter that is used for each of the broadcast standards.
    Type: Application
    Filed: March 4, 2008
    Publication date: September 18, 2008
    Inventors: Vyacheslav Shyshkin, Larry Silver, Warren Synnott, Steve Selby, Chris Ouslis, Lance Greggain
  • Publication number: 20080225176
    Abstract: Various embodiments are described herein for automatic gain control techniques that can be used by a universal television receiver that is capable of processing television channel signals broadcast according to a variety of analog and digital broadcast standards.
    Type: Application
    Filed: March 4, 2008
    Publication date: September 18, 2008
    Inventors: Steve Selby, Chris Ouslis, Christina Chiu
  • Publication number: 20080225174
    Abstract: Various embodiments are described herein for a universal television receiver that is capable of processing television channel signals broadcast according to a variety of analog and digital broadcast standards. In particular, various embodiments are provided for avoiding interferers in a desired television channel signal and these embodiments generally include changing sampling rate, shifting certain oscillation frequencies or changing sampling rate and shifting certain oscillation frequencies.
    Type: Application
    Filed: February 27, 2008
    Publication date: September 18, 2008
    Inventors: Lance Greggain, Vyacheslav Shyshkin, Chris Ouslis, Steve Selby
  • Patent number: 7425994
    Abstract: A video decoder (14). The decoder comprises an interface (30) for receiving a set of an integer number S of analog input signals at a same time. The decoder also comprises circuitry for processing the S analog input signals, and that circuitry comprises an integer number N of analog-to-digital converters (38x) for producing a set of the integer number S of digital signals. Each digital signal in the set of S of digital signals corresponds to a respective different one of the S analog input signal, and N is less than S. The decoder also comprises output circuitry (40x, 42x), coupled to the circuitry for processing, for providing each digital signal in the set of S of digital signals to a different respective output conductor.
    Type: Grant
    Filed: January 31, 2005
    Date of Patent: September 16, 2008
    Assignee: Texas Instruments Incorporated
    Inventors: Towfique Haider, Jason Meiners
  • Patent number: 7425993
    Abstract: A method of generating an orthogonally sampled video signal based on a line phase measure. In a first aspect the input signal is sampled by a clock locked to the average line frequency of a video input and the resulting samples are time shifted, optionally with or without interpolation, to an orthogonal sampling grid. In a second aspect input samples are taken and shifted to an orthogonal sampling grid according to a line phase measure. The line phase measure can be derived from a number of measurements or interpolated. In one embodiment a delay is employed so that a measure of a later sample is used to shift an earlier sample.
    Type: Grant
    Filed: May 29, 2003
    Date of Patent: September 16, 2008
    Assignee: Snell & Wilcox Limited
    Inventors: Barry Flannaghan, Martin Weston
  • Publication number: 20080170157
    Abstract: A video signal processing system including a digital signal processing (DSP) module, a digital offset module coupled to the DSP module, a gain module, and a digital to analog converter (DAC) coupled to the DSP module and to the gain module, wherein the DAC is configured to cause the gain module to provide multiple gain signals having predetermined first values to the DAC, cause, for each of the multiple gain signals, a digital input signal value to the DAC to be ramped up, determine, for each of the multiple gain signals, a lowest digital input signal value that causes an output voltage of the DAC to be at least as high as a reference voltage, and determine a second gain value that will cause the DAC to provide a desired DAC output voltage in response to the DAC receiving a reference DAC input value.
    Type: Application
    Filed: August 30, 2007
    Publication date: July 17, 2008
    Inventor: Brett Hilder
  • Patent number: 7391474
    Abstract: Display interface embodiments are provided to capture various types of analog video signals and digitize them for presentation on advanced digital displays (e.g., computer displays and television displays). The embodiments include at least an error converter channel and a reference converter channel that can each amplify an analog input signal S with a fixed gain G and a programmed gain g and convert the amplified signal to a corresponding digital code. The embodiments also include a channel controller that is configured to conduct process steps that adjust the transfer function of the error converter channel to conform to (e.g., matches) the transfer function of the reference converter channel.
    Type: Grant
    Filed: August 12, 2005
    Date of Patent: June 24, 2008
    Assignee: Analog Devices, Inc.
    Inventors: Ralph David Moore, Jr., Michael Joseph Fernald
  • Publication number: 20080129870
    Abstract: A system for overlaying a motion video signal onto an analog signal on a display. The system includes a motion video processing unit for receiving and processing the motion video signal into a signal having an analog video format, a video format analyzer and synchronizer device for receiving the analog signal and for determining video timing parameters and a corresponding original pixel clock of the analog signal and for controlling video timing parameters of the motion video signal to match the video timing parameters of the analog signal determined by the video format analyzer and synchronizer device so as to provide an output motion video signal which is synchronized with the analog signal and a display determining device for determining the display of the analog output signal or the synchronized output motion video signal on the display.
    Type: Application
    Filed: November 6, 2007
    Publication date: June 5, 2008
    Applicant: Sony Electronics Inc.
    Inventors: Mark A. Champion, David H. Bessel
  • Patent number: 7382298
    Abstract: Analog-to-digital converters (ADCs) generally make code errors as they convert analog display signals to digital display signals of digital displays. Code-correction structures are provided that correct these code errors by initially configuring the ADCs to provide digital signals with redundant resolution. In particular, analog display signal having 2N discrete analog levels are converted with M-bit ADCs wherein M exceeds N. This redundancy is utilized with a controller that distinguishes differences between an occurrence pattern of digital codes and a desired error-free pattern of digital codes. Subsequently, the controller corrects the digital code to reduce the observed differences.
    Type: Grant
    Filed: January 17, 2007
    Date of Patent: June 3, 2008
    Assignee: Analog Devices, Inc.
    Inventor: Willard Kraig Bucklen
  • Publication number: 20080088742
    Abstract: An AV player chip includes a TV encoder, a timing controller, a multiplexer and a plurality of digital-to-analog converters. The TV encoder is used for transforming a first image signal into a TV video signal. The timing controller is used for generating an output signal. The multiplexer includes a first set of input ends coupled to the TV encoder, a second set of input ends coupled to the timing controller, a control end and a set of output ends. The multiplexer outputs the TV video signal or the output signal to the set of output ends according to a control signal received by the control end. The plurality of digital-to-analog converters are coupled to the set of output ends of the multiplexer for transforming the TV video signal into a first playing signal and for transforming the output signal into a second playing signal.
    Type: Application
    Filed: March 15, 2007
    Publication date: April 17, 2008
    Inventors: Sung-Hung Li, Wei-Chih Huang
  • Patent number: 7358882
    Abstract: A video processing method and apparatus to employing an analog user interface and a digital video decoder. A working mode is provided, according to which analog control signals from the analog user interface are selectively directed to an analog-to-digital converter. The analog control signal is converted to digital control signal to accordingly control the digital video decoder.
    Type: Grant
    Filed: June 16, 2006
    Date of Patent: April 15, 2008
    Assignee: Beyond Innovation Technology Co., Ltd.
    Inventors: Chia-Hsin Chen, Chiu-Yuan Lin, Bor-Yuh Chang
  • Publication number: 20080062321
    Abstract: A video receiver for SCART input includes an input configured to receive a composite video signal, RGB signals, and a switch-indicating signal, a first digitizer module coupled to the input and including a one-bit slicer configured to receive and convert the switch-indicating signal to a one-bit digital signal, the first digitizer further including a downconverter configured to convert the one-bit signal to a multi-bit digital signal with non-abrupt transitions between a logical zero and a logical one, and a combiner module configured to receive and combine indicia of the composite video signal and the RGB signals to produce a total video output signal as a function of the indicia of the multi-bit digital signal.
    Type: Application
    Filed: August 24, 2006
    Publication date: March 13, 2008
    Inventors: Dongsheng Wu, Huijuan Liu
  • Publication number: 20080055472
    Abstract: An image signal processing apparatus includes a clamp circuit that clamps an image signal having a horizontal synchronization signal, an optical black level period representing an optical black level, and an effective signal period representing an image signal for one horizontal line so as to clamp a value offset from the image signal on the basis of a first reference value during the optical black level period and to clamp the image signal on the basis of a second reference value different from the first reference value during the effective signal period, and a level computation circuit that determines the second reference value on the basis of a signal level clamped during the optical black level period.
    Type: Application
    Filed: August 23, 2007
    Publication date: March 6, 2008
    Applicants: SANYO ELECTRIC CO., LTD., SANYO SEMICONDUCTOR CO., LTD.
    Inventor: Toshio Nakakuki
  • Patent number: 7339628
    Abstract: Video decoder systems in which both the analog-to-digital converter and the composite decoder are driven by the stable sample clock, such as a crystal source. The outputs of the composite decoder are provided to a source rate converter, having an output that is provided to a digital output formatter. The digital output formatter is driven by the output clock, which may be locked to the source clock if desired. The output clock is developed by a clock generator which may be one of several different types, including a fractional N synthesizer, a direct digital synthesizer or a puncture clock.
    Type: Grant
    Filed: October 13, 2004
    Date of Patent: March 4, 2008
    Assignee: Cirrus Logic, Inc.
    Inventors: Daniel Gudmondson, John L. Melanson, Rahul Singh, James A. Antone, Ahsan Habib Chowdhury, Krishnan Subramoniam
  • Publication number: 20080043147
    Abstract: A display apparatus is provided. The display apparatus includes: a signal input part which receives a video signal; a signal processor which processes the video signal inputted through the signal input part according to a predetermined offset value; a controller which compensates the offset value of the signal processor to make the output black level equal to the standard black level if the output black level is not equal to the standard black level.
    Type: Application
    Filed: May 10, 2007
    Publication date: February 21, 2008
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventor: Young-hun CHOI
  • Publication number: 20080030620
    Abstract: An analog front end circuit is provided, which comprises at least one converting circuit. Each converting circuit further comprises a clamper, a low-pass filter, an input buffer and a sigma-delta analog-to-digital converter. By using the sigma-delta analog to digital converter, the invention not only increases the resolution, but reduces the order of an anti-aliasing filter, therefore reducing the size and the power consumption of the analog circuit.
    Type: Application
    Filed: July 27, 2007
    Publication date: February 7, 2008
    Inventors: Jui-Yuan Tsai, Wen-Chi Wang, Chang-Shun Liu
  • Publication number: 20080030584
    Abstract: The invention discloses an image processing system comprising a video source system, a transmission medium, and a television system. The image processing systems of the video source system and the television system are equipped with an additional digital-to-analog converter and an additional analog-to-digital converter.
    Type: Application
    Filed: July 25, 2007
    Publication date: February 7, 2008
    Inventors: Jui-Yuan Tsai, Chao-Hsin Lu
  • Patent number: 7324162
    Abstract: A video decoder in which 1) resolution quality can be improved for a given bit count analog-to-digital converter, 2) a lower bit count analog-to-digital converter can be used with substantially similar quality or 3) a combination of improved resolution quality with a lower bit count analog-to-digital converter can be done. In the preferred embodiment, a DC bias is added to the video signal after the sync portion of the composite signal has been received and prior to the active video being received. This bias is then removed after the end of the active video period. By applying this bias, the DC voltage level of the video signals is actually reduced, so that the full scale value of the analog-to-digital conversion process can also be reduced. Thus, compared to using an unbiased signal, increased A/D converter resolution is obtained. In an alternative embodiment, the sync portion can be biased upwardly during the front porch and then be returned during the back porch.
    Type: Grant
    Filed: October 13, 2004
    Date of Patent: January 29, 2008
    Assignee: Cirrus Logic, Inc.
    Inventors: Daniel Gudmondson, Shyam Somayajula
  • Patent number: 7321399
    Abstract: A system such as an audio and/or video system includes a multiplexed analog-to-digital converter arrangement. The arrangement includes an ADC for converting first and second analog signals to first and second digital signals, respectively, and for outputting the first digital signal during a first time interval and outputting the second digital signal during a second time interval. A digital filter is provided for filtering the first and second digital signals to generate first and second filtered signals, respectively, and for outputting the first and second filtered signals in a time-aligned manner during a third time interval.
    Type: Grant
    Filed: December 6, 2002
    Date of Patent: January 22, 2008
    Assignee: Thomson Licensing
    Inventor: Mark Francis Rumreich
  • Patent number: 7286176
    Abstract: A processing system for a charge coupled device (CCD) or CMOS imaging system includes a multi-mode, multiple current level, correlated double sample and variable gain (CDS/VGA) circuit for receiving data from a CCD system, subject to horizontal and vertical timing signals for the system which are locally generated by the processing system itself. The processing system particularly includes programmable timing circuitry for controlling the detection of pixel intensity values from elements of a two-dimensional pixel array, with a programmable low-frequency master vertical timing circuit driving a high-frequency horizontal timing circuit, wherein the vertical and horizontal timing signals are independently locally provided to the array from the analog processor actually sampling the array. The architecture of the processing system further includes a correlated double sampler, a black level clamp, and an A/D conversion module.
    Type: Grant
    Filed: April 8, 2004
    Date of Patent: October 23, 2007
    Assignee: Cirrus Logic, Inc.
    Inventors: Douglas R. Holberg, Sandra M. Johnson, Nadi R. Itani, Argos R. Cue
  • Publication number: 20070222893
    Abstract: A video signal converting device is capable of converting an analog composite signal into a proper digital signal with a small delay even if the analog composite signal contains much jitter. The video signal converting device has a sampling clock output unit for outputting a sampling clock signal having a frequency which is 4n times the frequency of a burst signal contained in the analog composite signal (n represents a positive integer of 2 or greater), and an analog-to-digital converting unit for converting the analog composite signal into a digital signal based on the sampling clock signal output from the sampling clock output unit.
    Type: Application
    Filed: September 6, 2006
    Publication date: September 27, 2007
    Applicant: FUJITSU LIMITED
    Inventors: Yuji Mori, Yoshihiro Nishioka
  • Publication number: 20070211173
    Abstract: The invention relates to an image processing chip and related method. The image processing chip includes a pin for receiving a composite signal; a synchronization signal detecting circuit, coupled to the pin, for extracting a synchronization signal from the composite signal; a clamping circuit, coupled to the pin, for adjusting a voltage level of the composite signal according to the synchronization signal; and an analog to digital converter, coupled to the pin, for generating a video signal by sampling the composite signal.
    Type: Application
    Filed: March 13, 2007
    Publication date: September 13, 2007
    Inventors: Jin-Sheng Gong, Jui-Yuan Tsai, Yu-Pin Chou, Yueh-Hsing Huang
  • Patent number: 7265695
    Abstract: A video signal processing apparatus comprises an A/D converter for digitizing an analog video signal, an integration circuit for integrating the digitized video signal within a predetermined integration range, a picture display device for displaying a picture based on an integration output, and a control unit which, when an offset adjustment signal is inputted to the A/D converter, corrects the offset value so as to eliminate a difference between the integration value of the integration circuit and a preliminarily set specified value, and determines whether or not offset adjustment is completed based on the number of times when the corrected offset value is within a range defined by adding a predetermined error to the specified value.
    Type: Grant
    Filed: June 10, 2005
    Date of Patent: September 4, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shigeki Kamimura, Tadashi Oguma
  • Patent number: 7233365
    Abstract: Digital dc restore methods and apparatus to restore the DC component of an analog waveform to a quantized reference value level at a given temporal point on a waveform, prior to an ADC. This may used to establish the relationship between the full scale digital value out of the ADC and the waveform being digitized. For a video signal, the Digital Value of Black, is compared with the value on the back porch of the video signal. The difference is converted to the analog domain by a DAC clocked at the Temporal Point to provide a sample and hold function. An amplifier compares the difference, mapped to one half full scale digital, to an analog common mode voltage for the ADC, removing any error due to the difference between them. Other applications include correlated double sampling of contact image sensors to remove Dark Current Offset.
    Type: Grant
    Filed: September 1, 2004
    Date of Patent: June 19, 2007
    Assignee: Maxim Integrated Products, Inc.
    Inventor: William M. Stutz
  • Patent number: 7227588
    Abstract: A clamping system for clamping a video signal, wherein the clamping system uses a charge-pump unit in company with a digital clamping controller to clamp the potential of the video signal, prior to the video signal being input to a programmable gain amplifier and an A/D converter, so as to reach a desired level. The charge-pump unit provides two charge-pump circuits, wherein one charge-pump circuit supplies a strong burst to boost the potential of the video signal while the video signal is below a threshold value. Otherwise, the other charge-pump circuit supplies a weak burst to fine tune the potential of the video signal when the video signal has reached the threshold value.
    Type: Grant
    Filed: August 17, 2004
    Date of Patent: June 5, 2007
    Assignee: VXIS Technology Corp
    Inventors: Yuan-Hao Huang, Hsien-Chih She, Chun-Cheng Huang, Shang-Yi Lin, Jen-Shi Wu
  • Patent number: 7167211
    Abstract: An A/D conversion apparatus of a digital video system includes an A/D converter for converting an input analog video signal to a digital signal on the basis of a reference voltage value input from the outside and outputting the digital signal; and a reference voltage supplying portion for supplying the A/D converter with a predetermined number of the reference voltage value sequentially and repeatedly during a predetermined time period. Accordingly, since the quantization error can be minimized during the A/D conversion in the digital video system without increasing the number of the quantization bits, the image quality can be improved.
    Type: Grant
    Filed: August 13, 2003
    Date of Patent: January 23, 2007
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Ho-woong Kang
  • Patent number: 7148931
    Abstract: An apparatus and a method for signal processing in a digital video system. The apparatus for signal processing of a digital video system has: an input unit to receive a signal quantized for M bits; and an output unit to output a value of A for (2M?N?B)times and a value of A+1 for B times during vertical scan of 2M?N times when a decimal value of high N bits is A and a decimal value of low bits of (M?N) excluding N bits is B and M>N. Accordingly, as an image signal quantized with a greater number of bits is displayed on a screen with a lesser number of bits, the quality of a picture can be improved.
    Type: Grant
    Filed: May 8, 2003
    Date of Patent: December 12, 2006
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Ho-woong Kang
  • Patent number: 7133450
    Abstract: The present invention relates to methods and devices for compression and multi-screen process of digital video signals by multi-thread scaling. The method comprises. (a) a step to scale the resolutions of digital video signals; and (b) a step to compress or process for multi-screens the scaled digital video signals. The device comprises: multi-channel analog/digital converters, a compression FIFO; a multi-screen FIFO; a CPU which initializes each channel's analog/digital converter, and a video processor which transmits to the video memory. The processor for compression/multi-screen process may conduct the compression and multi-screen process sequentially from the compression FIFO and the multi-screen FIFO depending on the even/odd fields of the signals Thus, the method and device uses N analog/digital converters for the same N channels while providing the same function as the conventional system.
    Type: Grant
    Filed: February 19, 2001
    Date of Patent: November 7, 2006
    Assignee: Posdata Company Ltd.
    Inventor: Cha-Gyun Jeong