Chrominance Channel Circuitry Patents (Class 348/713)
  • Patent number: 10516370
    Abstract: A predistorter has a first capacitor, a first bias input circuit, a second bias input circuit, a second capacitor and an impedance conversion circuit. A first end of the first capacitor is coupled to a first node of the amplifier. The impedance conversion circuit has a first resistor and a field-effect transistor (FET) and is used to perform an impedance conversion to provide a variable capacitance. A gate of the FET is coupled to an output end of the first bias input circuit, one of a source and a drain of the FET is coupled to a second end of the first capacitor and a first end of the first resistor, and another of the source and the drain of the FET is coupled to an output end of the second bias input circuit, first end of the second capacitor and a second end of the first resistor.
    Type: Grant
    Filed: June 26, 2019
    Date of Patent: December 24, 2019
    Assignee: RichWave Technology Corp.
    Inventors: Chih-Sheng Chen, Pei-Chuan Hsieh
  • Patent number: 9007395
    Abstract: Devices, systems, apparatuses, methods, and other embodiments associated with bit resolution enhancement are described. In one embodiment, an apparatus includes logic configured to produce a high-resolution pixel from a low-resolution pixel. The apparatus includes logic configured to classify the high-resolution pixel as being in a smooth region of an image based on at least one of a gradient value and a variance value associated with the low-resolution pixel. The apparatus includes logic configured to selectively re-classify the high-resolution pixel as not being in the smooth region of the image based on a set of neighboring high-resolution pixels associated with high-resolution pixel. The apparatus includes logic configured to selectively filter the high-resolution pixel based on whether the high-resolution pixel remains classified as being in the smooth region of the image.
    Type: Grant
    Filed: November 10, 2009
    Date of Patent: April 14, 2015
    Assignee: Marvell World Trade Ltd.
    Inventors: Vasudev Bhaskaran, Nikhil Balram, Sujith Srinivasan, Sanjay Garg
  • Patent number: 9001275
    Abstract: HDMI is a digital audio and video communications protocol commonly used in consumer electronics. HDMI is particularly synonymous with high fidelity audio and video. Even though HDMI is a digital communications protocol, the audio quality can be impaired by analog signal impairments and distortions even if there are no digital decoding errors. In particular, the very process by which the audio is converted from Digital (HDMI) to human audible “Analog Audio” can be prone to errors. This occurs when the Digital to Analog Converter (DAC) clock, which is derived from the HDMI TMDS clock or HDMI source, is “distorted” due to its jitter, resulting in erroneous sampling or outputting of vital audio samples, thereby reducing the audio quality of the experience. The present invention reduces the jitter on the TMDS clock, and hence the audio DAC clock, resulting in lower audio distortion.
    Type: Grant
    Filed: November 19, 2013
    Date of Patent: April 7, 2015
    Inventors: Andrew Joo Kim, David Anthony Stelliga
  • Publication number: 20150077640
    Abstract: To optimize combinations of values of four primary colors in a display device supporting four-primary-color display, with consideration given to display performances such as the power consumption in a light-emitting display device and the viewing angle characteristics in the non-light-emitting display device. The display device of the present invention displays video indicated by an input video signal using pixels composed of four primary colors and each having at least one sub-pixel for one primary color. When representing pixel colors of pixel signals in the input video signal, at least one pixel color which has a lightness less than a predetermined lightness determined depending on a color gamut representable by the display device and which is in areas except on a boundary of the color gamut is represented using only three primary colors among the four primary colors.
    Type: Application
    Filed: September 6, 2012
    Publication date: March 19, 2015
    Applicant: SHARP KABUSHIKI KAISHA
    Inventor: Takashi Kanda
  • Patent number: 8659614
    Abstract: An image display apparatus adapted to display an image based on an image signal input includes: a color adjustment circuit adapted to perform one of a modification process and a correction process individually on a hue signal, a lightness signal, and a saturation signal included in first HLS signals as an image signal, and output the processed signals as second HLS signals.
    Type: Grant
    Filed: March 23, 2010
    Date of Patent: February 25, 2014
    Assignee: Seiko Epson Corporation
    Inventor: Fumio Koyama
  • Patent number: 8547483
    Abstract: An image processing method includes receiving an image data including a first pixel, a second pixel and a third pixel, the second pixel being between the first pixel and the third pixel; calculating a difference between two initial chrominance values of the first pixel and two initial chrominance values of the second pixel to determine a first difference, and calculating a difference between the two initial chrominance values of the second pixel and two initial chrominance values of the third pixel to determine a second difference; comparing the first difference with the second difference to select either the first pixel or the third pixel as a target pixel; and determining two adjusted chrominance values of the second pixel according to at least two initial chrominance values of the target pixel.
    Type: Grant
    Filed: August 31, 2010
    Date of Patent: October 1, 2013
    Assignee: MStar Semiconductor, Inc.
    Inventors: Mei-Ju Chen, Jen-Shi Wu, Wei-Kuo Lee
  • Patent number: 8368816
    Abstract: A circuit for detecting motion pictures includes a first-stage motion picture detecting unit and a second-stage motion picture detecting unit. The first-stage motion picture detecting unit analyzes a current image frame and a previous image frame to calculate a first motion value associated with the current image frame. The second-stage motion picture detecting unit receives the first motion value, compares the first motion value against an adjusted motion value, and outputs and stores a larger one as a second motion value. The adjusted motion value is a value derived by adjusting an adjacent previous second motion value.
    Type: Grant
    Filed: July 28, 2009
    Date of Patent: February 5, 2013
    Assignee: Novatek Microelectronics Corp.
    Inventor: Teng-Yi Lin
  • Patent number: 8014598
    Abstract: A method of changing a pixel color includes determining whether a chrominance of a pixel is in a preference chrominance area, where the preference chrominance area is defined as a conic section in a two-dimensional chrominance plane and an eccentricity of the conic section is not greater than 1, and changing the chrominance of the pixel to a preference chrominance to generate a preference pixel when the chrominance of the pixel is in the preference chrominance area. Therefore, the method may set a preference chrominance area in a simple manner, and hardware for setting the preference chrominance area may be easily implemented.
    Type: Grant
    Filed: June 21, 2007
    Date of Patent: September 6, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hwa-Hyun Cho, Bom-Yun Kim, Jong-Seon Kim
  • Patent number: 8009963
    Abstract: This disclosure describes adaptive filtering techniques to improve the quality of captured imagery, such as video or still images. In particular, this disclosure describes adaptive filtering techniques that filter each pixel as a function of a set of surrounding pixels. An adaptive image filter may compare image information associated with a pixel of interest to image information associated with a set of surrounding pixels by, for example, computing differences between the image formation associated with the pixel of interest and each of the surrounding pixels of the set. The computed differences can be used in a variety of ways to filter image information of the pixel of interest. In some embodiments, for example, the adaptive image filter may include both a low pass component and high pass component that adjust as a function of the computed differences.
    Type: Grant
    Filed: March 16, 2006
    Date of Patent: August 30, 2011
    Assignee: QUALCOMM Incorporated
    Inventors: Prasanjit Panda, Khaled Helmi El-Maleh, Hsiang-Tsun Li
  • Patent number: 7817303
    Abstract: This invention provides an image processing device and a printing apparatus that obviate the need for manual processing on the part of the user or operator and which can automatically perform an optimum image correction without using added information such as photographing information. For this purpose, this invention including: a highly chromatic color area detection unit to detect highly chromatic color area in an original image according to the input color image data; a concentration calculation unit to calculate a concentration level of the highly chromatic color area; and a print data generation unit to generate output color image data according to the concentration level of the highly chromatic color area.
    Type: Grant
    Filed: October 11, 2005
    Date of Patent: October 19, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventors: Minako Kato, Shigeyasu Nagoshi
  • Patent number: 7595842
    Abstract: A system and method for determining whether to process a signal using three-dimensional comb filtering. Various aspects of the present invention may comprise method steps and system components that generate an inter-frame chroma signal. Various aspects may generate a filtered inter-frame chroma signal by removing a band of frequency components from the inter-frame chroma signal that generally corresponds to chroma signal components. Various aspects may analyze the filtered inter-frame chroma signal to determine whether three-dimensional comb filtering may be appropriate. Various aspects may comprise method steps and components that generate inter-frame and intra-frame luma signals. Various aspects may generate filtered inter-frame and intra-frame luma signals by removing frequency components from the inter-frame and intra-frame luma signals, respectively, that fall outside a frequency band near the chroma sub-carrier frequency.
    Type: Grant
    Filed: March 14, 2007
    Date of Patent: September 29, 2009
    Assignee: Broadcom Corporation
    Inventors: Alexander G. MacInnis, Sheng Zhong
  • Patent number: 7535514
    Abstract: We describe an apparatus and method for decoding a SECAM chrominance signal. The apparatus may include a band-pass filter to separate the chrominance signal from the composite video baseband signal. A down-mixer down mixes the chrominance signal from a high to a low frequency band to generate two signals having a substantially 90° phase difference. A cloche filter filters the two signals. A differentiator differentiates the cloche filtered signals. A multiplier squares each differentiated signal. An adder sums the squared result while a square root takes the square root of the sum.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: May 19, 2009
    Assignee: Samung Electronics Co., Ltd.
    Inventors: Deuk-Geun Ahn, Bong-Soon Kang, Joo-Young Ha, Ju-Hyun Kim
  • Publication number: 20080018801
    Abstract: A method of changing a pixel color includes determining whether a chrominance of a pixel is in a preference chrominance area, where the preference chrominance area is defined as a conic section in a two-dimensional chrominance plane and an eccentricity of the conic section is not greater than 1, and changing the chrominance of the pixel to a preference chrominance to generate a preference pixel when the chrominance of the pixel is in the to preference chrominance area. Therefore, the method may set a preference chrominance area in a simple manner, and hardware for setting the preference chrominance area may be easily implemented.
    Type: Application
    Filed: June 21, 2007
    Publication date: January 24, 2008
    Inventors: Hwa-Hyun Cho, Bom-Yun Kim, Jong-Seon Kim
  • Patent number: 7227587
    Abstract: A system and method for determining whether to process a signal using three-dimensional comb filtering. Various aspects of the present invention may comprise method steps and system components that generate an inter-frame chroma signal. Various aspects may generate a filtered inter-frame chroma signal by removing a band of frequency components from the inter-frame chroma signal that generally corresponds to chroma signal components. Various aspects may analyze the filtered inter-frame chroma signal to determine whether three-dimensional comb filtering may be appropriate. Various aspects may comprise method steps and components that generate inter-frame and intra-frame luma signals. Various aspects may generate filtered inter-frame and intra-frame luma signals by removing frequency components from the inter-frame and intra-frame luma signals, respectively, that fall outside a frequency band near the chroma sub-carrier frequency.
    Type: Grant
    Filed: March 5, 2004
    Date of Patent: June 5, 2007
    Assignee: Broadcom Corporation
    Inventors: Alexander G. MacInnis, Sheng Zhong
  • Patent number: 7224406
    Abstract: A digital signal processing system and method applied for chroma transition, wherein the method has the acts of: performing a difference process on an original chroma signal C to obtain a first difference signal C?; calculating an absolute value |C?| of the first difference signal C?; performing a difference process on the absolute value |C?| to obtain a second difference signal Ca?; determining whether the second difference signal Ca? is a positive signal or a negative signal; wherein based on a determined result, an optimized chroma signal is generated by either mixing the original input chroma signal C with a k-delayed chroma signal, or mixing the k-delayed chroma signal C[n?k] with a 2k-delayed chroma signal C[n?2k], where k is a constant.
    Type: Grant
    Filed: August 16, 2004
    Date of Patent: May 29, 2007
    Assignee: VXIS Technology Corp.
    Inventors: Ming-Hsiu Lee, Yuan-Hao Huang
  • Patent number: 7151576
    Abstract: A luminance component of a video signal is modulated in a first frequency band. A first chrominance component of the video signal is modulated in a second frequency band and is mixed with an audio component. A second chrominance component of the video signal is modulated in a third frequency band. The modulated luminance component, the first modulated chrominance component, and the second modulated chrominance component are then transmitted across a communication link.
    Type: Grant
    Filed: May 31, 2005
    Date of Patent: December 19, 2006
    Assignee: Microsoft Corporation
    Inventor: Louis F. Coffin, III
  • Patent number: 7145605
    Abstract: An apparatus for synchronizing chroma and luma data includes a first handshake block for luma data, a second handshake block for chroma data, and a means for providing a handshake signal to the first block and to the second block based at least in part on a determination that they are both ready to transfer data, and further for inhibiting provision of the handshake signal based at least in part on a determination that at least one of the first block and the second block is not ready to transfer data.
    Type: Grant
    Filed: November 22, 2002
    Date of Patent: December 5, 2006
    Assignee: Thomson Licensing
    Inventor: Paul Dean Filliman
  • Patent number: 7136112
    Abstract: A luminance component of a video signal is modulated in a first frequency band. A first chrominance component of the video signal is modulated in a second frequency band and is mixed with an audio component. A second chrominance component of the video signal is modulated in a third frequency band. The modulated luminance component, the first modulated chrominance component, and the second modulated chrominance component are then transmitted across a communication link.
    Type: Grant
    Filed: May 31, 2005
    Date of Patent: November 14, 2006
    Assignee: Microsoft Corporation
    Inventor: Louis F. Coffin, III
  • Patent number: 6956622
    Abstract: A luminance component of a video signal is modulated in a first frequency band. A chrominance component of the video signal is modulated in a second frequency band. The modulated luminance component and the modulated chrominance component are then transmitted across a communication link.
    Type: Grant
    Filed: June 27, 2002
    Date of Patent: October 18, 2005
    Assignee: Microsoft Corporation
    Inventor: Louis F. Coffin, III
  • Patent number: 6496227
    Abstract: A system with chrominance delay lines has a first sampled channel including at least one smoothing filter, and has a second unsampled channel. A continuous bypass filter is placed in the second channel to balance the pulse response from these two channels.
    Type: Grant
    Filed: May 21, 1999
    Date of Patent: December 17, 2002
    Assignee: STMicroelectronics S.A.
    Inventor: Régis Lemaitre
  • Patent number: 6480241
    Abstract: In an S-video signal processor, the luminance signal is amplified and adjusted over selected frequency ranges using a parallel signal for shaping the S-video signal response and permitting the S-video signal to be transmitted over exceptionally long transmission lines while providing a quality picture. In separate channels, chrominance and luminance signals are amplified and impedance matched. A luminance band pass filter permits manual adjustments to a lower range of video signal frequencies and thus changes to white level picture information. One version of the S-video signal processor includes a positive feedback network which permits user adjustments in an upper video signal frequency range having picture super detail information for providing a picture of high resolution and thus pleasing to the user. In a second version a compensation amplifier is used to alter the frequency response of the luminance signal.
    Type: Grant
    Filed: January 6, 2000
    Date of Patent: November 12, 2002
    Assignee: Gordon J. Gow Technologies, Inc.
    Inventor: Jeffrey A. Boccaccio
  • Patent number: 6411340
    Abstract: A chrominance signal processing apparatus in a video signal processing system which has a simple configuration capable of achieving chrominance signal control and RGB transform functions using a single circuit.
    Type: Grant
    Filed: November 19, 1999
    Date of Patent: June 25, 2002
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ho-Seong Lee, Hong-Ki Park
  • Patent number: 6400412
    Abstract: A video signal processing apparatus having first and second analog/digital converters for converting imputted analog luminance and chrominance component signals into digital luminance and chrominance component signal. Frequency band limiting filters, disposed on a pre-stage of the first and second analog/digital converters, limit a frequency band of the analog luminance and chrominance component signals, the chrominance component signal frequency band limiting filter having a group delay characteristic different from a group delay characteristic of the luminance component signal frequency band limiting filter by a predetermined delay time. A time adjustment circuit adjusts the timing of the digital chrominance signal to match with the digital luminance signal.
    Type: Grant
    Filed: August 4, 1998
    Date of Patent: June 4, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventor: Toshihiko Suzuki
  • Patent number: 6271881
    Abstract: A color image pickup apparatus includes a photo-to-electric conversion section subjected to progressive scanning. A first delay circuit defers an output signal of the photo-to-electric conversion section. A first adder combines the output signal of the photo-to-electric conversion section and an output signal of the first delay circuit. A second delay circuit defers the output signal of the first delay circuit. A second adder combines the output signal of the photo-to-electric conversion section and an output signal of the second delay circuit. A third delay circuit defers an output signal of the first adder. A first subtracter implements subtraction between the output signal of the first adder and an output signal of the third delay circuit. A fourth delay circuit defers an output signal of the second adder. A second subtracter implements subtraction between the output signal of the second adder and an output signal of the fourth delay circuit.
    Type: Grant
    Filed: April 27, 1998
    Date of Patent: August 7, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yuichirou Takahashi, Atsuto Kanazawa, Masaki Kariya, Masayuki Serizawa, Kenji Tamura, Kikuo Kobayashi, Masaaki Nakayama, Hiromichi Tanaka
  • Patent number: 6249323
    Abstract: In a white balance control, correction signals are added to input chrominance signals (Uin, Vin) to obtain output chrominance signals (Uout, Vout). Chrominance sum signals are derived from the input and output chrominance signals (Uin, Vin ; Uout, Vout) and reference chrominance signals (Uref, Vref). Exponential signals are derived from the chrominance sum signals, and the reference chrominance signals (Uref, Vref) are multiplied by the exponential signals to obtain the correction signals.
    Type: Grant
    Filed: May 18, 1998
    Date of Patent: June 19, 2001
    Assignee: U.S. Philips Corporation
    Inventor: Victor H. J. Van Der Voort
  • Patent number: 6172716
    Abstract: Improved circuitry for adjusting the video gain, black level, chroma gain and burst phase of a video signal includes composite to Y/C splitter, luminance processing section, sync separator and chroma processor. Unity and split mode selection is provided. A meter circuit provides display of black and white levels as well as clip indication.
    Type: Grant
    Filed: January 25, 1997
    Date of Patent: January 9, 2001
    Inventor: James A. Karlock
  • Patent number: 6160593
    Abstract: An image signal processor generates color difference output signals from color component signals representative of image data. The image signal processor includes multiple color calculators that generate multiple sets of primary color signals from the color component signals. Multiple color difference calculators connected to the color calculators generate multiple sets of color difference signals using the respective sets of primary color signals. A synthesizing circuit combines the multiple sets of color difference signals using a predefined ratio to generate the color difference output signals. By generating multiple sets of signals, errors due to noise can be filtered and higher quality images produced.
    Type: Grant
    Filed: December 22, 1998
    Date of Patent: December 12, 2000
    Inventor: Toshio Nakakuki
  • Patent number: 6028647
    Abstract: An input high frequency signal passes through a PIN diode having a variable high frequency resistance and is output from an AGC circuit. The PIN diode is connected so as to be biased forward between an AGC signal level and a fixed voltage level (such as ground potential). A bias resistor and a coil are connected in series between a node on the output side of the PIN diode and a node supplied with the ground potential. More specifically, the resistor and the coil are inserted in parallel between the transmission path for high frequency signals and the ground potential.
    Type: Grant
    Filed: July 1, 1997
    Date of Patent: February 22, 2000
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Seiichirou Fukai, Shigeto Masuda
  • Patent number: 5844629
    Abstract: A digital-to-analog video encoder method and apparatus having unique equalization are disclosed. The encoder converts digital video signals into one or more analog video formats using one or more digital-to-analog converters. Equalization is provided to compensate for zero order hold effects of the digital-to-analog converters. Equalization is provided to a luminance signal and/or a chroma signal to equalize RGB, composite video, and super VHS video outputs. Multiplexed digital-to-analog converter inputs allow selection of several output formats.
    Type: Grant
    Filed: May 30, 1996
    Date of Patent: December 1, 1998
    Assignee: Analog Devices, Inc.
    Inventors: Brian P. Murray, Philip A. Curran, Colm J. Prendergast, Timothy J. Cummins
  • Patent number: 5812213
    Abstract: A video signal processing apparatus for separating a video input into a luminance signal and a chroma signal which are sent respectively for individualized special effect processing. Special effect signals are fed to a control unit. The levels of a luminance signal and a chroma signal having undergone the special effect processing are estimated by a program. Based on the result of the estimate, a limiter controls the gains of the chroma signal following the special effect processing. In this setup, the gains of the chroma signal are controlled so that the level of a composite video signal will fall within a predetermined range of levels in keeping with the contents of the special effect processing performed on the luminance signal and chroma signal.
    Type: Grant
    Filed: April 3, 1997
    Date of Patent: September 22, 1998
    Assignee: Sony Corporation
    Inventor: Katsuakira Moriwake
  • Patent number: 5805238
    Abstract: The 25 Hz offset present in the subcarrier frequency of the PAL television standard causes residual and phase modified subcarrier to be left on the luminance signal, which can produce undesirable visual artifacts in the picture. In order to filter luminance therefore without loss of resolution, an adaptive luminance filtering process and structure are provided. Due to the wide range of sample frequencies that must be dealt with, there are e.g. three separate filters available selectable under software control depending on the particular video standard being filtered, i.e. for various of the of NTSC and PAL television standards. The adaptive notch filter is switched on during times of low video transitions and is by-passed during high video transitions, thus avoiding loss of resolution during the high video transitions.
    Type: Grant
    Filed: May 14, 1996
    Date of Patent: September 8, 1998
    Assignee: Raytheon Company
    Inventors: Dean L. Raby, John A. Eldon
  • Patent number: 5784126
    Abstract: For an S-video signal, providing luminance and chrominance, luminance is amplified and adjusted over selected frequency ranges for shaping the S-video signal response for permitting the S-video signal to be transmitted over exceptionally long transmission lines while providing a quality picture. In separate channels, chrominance and luminance signals are amplified and impedance matched. A luminance band pass filter permits manual adjustments to a lower range of video signal frequencies and thus changes to white level picture information. A positive feedback network permits user adjustments in an upper video signal frequency range having picture super detail information for providing a picture of high resolution and thus pleasing to the user. A clear picture, brighter and sharper, rather than simply a brighter picture is available whether transmitted over a few or few hundred feet from a video source to the monitor.
    Type: Grant
    Filed: August 27, 1996
    Date of Patent: July 21, 1998
    Assignee: Gordon J. Gow Technologies, Inc.
    Inventor: Jeffrey Alan Boccaccio
  • Patent number: 5710545
    Abstract: A display (100) provides reversible contrasting indicia (112, 114) in order to accommodate an increased number of easily distinguishable indicia on the display. The display provides a first contrast mode (200) in which one set of indicia (112) become visually more prominent than another set (114) and a second contrast mode (300) in which the contrast of the first contrast mode is reversed. Selecting between the first and second contrast modes (200, 300) is controlled by backlighting of the display (100).
    Type: Grant
    Filed: October 10, 1995
    Date of Patent: January 20, 1998
    Assignee: Motorola, Inc.
    Inventor: Dustin E. Dunn
  • Patent number: 5657094
    Abstract: A video signal processing apparatus for separating a video input into a luminance signal and a chroma signal which are sent respectively for individualized special effect processing. Special effect signals are fed to a control unit. The levels of a luminance signal and a chroma signal having undergone the special effect processing are estimated by a program. Based on the result of the estimate, a limiter controls the gains of the chroma signal following the special effect processing. In this setup, the gains of the chroma signal are controlled so that the level of a composite video signal will fall within a predetermined range of levels in keeping with the contents of the special effect processing performed on the luminance signal and chroma signal.
    Type: Grant
    Filed: August 29, 1995
    Date of Patent: August 12, 1997
    Assignee: Sony Corporation
    Inventor: Katsuakira Moriwake
  • Patent number: 5638138
    Abstract: A dynamic range and contrast modification method for electronic images, and digital and analogue implementations are disclosed. Dynamic range changes are accomplished by making linear and nonlinear modifications to the low frequency component. Contrast changes are accomplished by making cross dependent, linear, and nonlinear modifications to the high frequency component. Cross dependent modifications are modifications that depend upon the changes to the low frequency component. Modifications are achieved using processor elements that implement mathematical operations. An automatic gain control, AGC, is used to control the low frequency component modification for some embodiments.
    Type: Grant
    Filed: June 9, 1994
    Date of Patent: June 10, 1997
    Inventor: Charles B. Hickman
  • Patent number: 5555031
    Abstract: In a video signal processing circuit, an adaptive signal compression is realized by correcting the color saturation by multiplication of color difference signals (R-Y, G-Y) by a same correction factor in such a way that color signal values (R, G, B) remain below their respective maximally allowed values without the luminance (Y) being limited as well. Preferably, the correction factor is obtained in dependence upon a non-linearly compressed luminance signal (Y').
    Type: Grant
    Filed: October 3, 1994
    Date of Patent: September 10, 1996
    Assignee: U.S. Philips Corporation
    Inventor: Johannes H. J. M. Van Rooij
  • Patent number: 5552826
    Abstract: In order to achieve a digital video camera apparatus which decreases the number of components and facilitates connection with a digital VTR, a luminance signal Y and a color signal C input from external input terminals (110, 118) are converted into digital signals by A/D converters (136, 138) by sampling these signals respectively at the sampling frequency of a digital recording/reproduction device (113) and a frequency four times the subcarrier frequency, the digital signals are selected by selectors (135, 137) together with signals Y and C from a digital signal processing circuit (106), and the selected signals are supplied to the digital signal recording/reproduction device (113). Color-difference signals are supplied after their frequency is converted into the sampling frequency of the digital signal recording/reproduction device (113) by frequency converters (139a, 139b).
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: September 3, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Teruo Hieda, Osamu Ueda, Norihiro Kawahara
  • Patent number: 5550597
    Abstract: When an input component image signal is inputted in a signal processing step, a high-frequency signal emphasis processing like HPF is performed with respect to a luminance signal and a processing like LPF with replenishment of the low-midrange frequency signal is performed in an LPF step and a color signal step with respect to color difference signals. Then, the luminance signal and color difference signals are outputted by prescribed clock pulses. The clock pulse of the color difference signals may be set lower than the clock pulse of the luminance signal according to the condition of the image. Processed as above, a new component image signal (a luminance signal Y and any combination of color difference signals U and V, V and W, W and U) is generated from a conventional component image signal (Y and U, V, W) without loss in image information or image quality.
    Type: Grant
    Filed: June 26, 1995
    Date of Patent: August 27, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Ryukichi Wada, Fumio Suzuki, Yoshisuke Ohtsuru
  • Patent number: 5532829
    Abstract: A control circuit includes: a capacitor for normal reproduction which stores an output of a reproduction color burst level detection for automatic color signal level control in a color signal processing circuit at the time of normal reproduction in a video cassette recorder; a capacitor for special reproduction which stores an output of a reproduction color burst level detection for automatic color signal level control at the time of special reproduction in the video cassette recorder; a switch for changing-over between outputs of the capacitors to supply a selected output to a gain variable amplifier for color signal amplification; and applying circuit for applying a voltage of the capacitor for special reproduction to the capacitor for normal reproduction at the time of special reproduction.
    Type: Grant
    Filed: March 29, 1995
    Date of Patent: July 2, 1996
    Assignee: Rohm Co., Ltd.
    Inventor: Yasunori Kawamura
  • Patent number: 5528314
    Abstract: A vehicle antenna comprises a transparent, electrically conducting, film between the inner and outer glass sheets of a vehicle window. The film comprises a horizontally elongate principal element substantially parallel to and spaced from the upper edge portion of the window aperture and having an effective horizontal length of an odd multiple of one quarter of a predetermined wavelength and an impedance matching element. The impedance matching element comprises a main portion having a peripheral edge with a horizontal upper portion spaced below the principal element and a remainder spaced from the remaining edge portion of the window aperture so as to form a slot transmission line having an effective length of one half the wavelength, which is preferably in the commercial FM band. The impedance matching element further comprises a narrow vertical portion connecting the main portion to the principal element, so that the slot transmission line is parasitically coupled to the principal element.
    Type: Grant
    Filed: May 22, 1995
    Date of Patent: June 18, 1996
    Assignees: General Motors Corporation, Delco Electronics Corporation
    Inventors: Louis L. Nagy, Mark Bellinger, Douglas C. Martin
  • Patent number: 5502508
    Abstract: A gradation compensating apparatus comprises a skin color detecting circuit for detecting a skin color signal from an inputted color difference signal, a compensation amount controlling circuit for controlling the signal level by the skin color detecting signal as a compensating signal, an APL detecting circuit for detecting an APL level from an inputted luminance signal and for outputting the detected APL level as an APL voltage, an APL controlling circuit for controlling the compensating signal level by the APL voltage, an output circuit for outputting a compensating output voltage by controlling the compensating signal with an inputted dc voltage, and a CRT driving circuit for controlling the brightness of the picture by using the compensating output voltage as a cutoff reference voltage.
    Type: Grant
    Filed: June 30, 1994
    Date of Patent: March 26, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Minoru Kawabata, Atsuhisa Kageyama
  • Patent number: 5500739
    Abstract: A frequency-multiplexed video signal is generated in which a color-under signal and a second under signal are linearly combined with at least partially overlapping frequency spectra to form a composite under signal for an FM luma signal. The frequency-multiplexed video signal is suited for recording on magnetic tape using helical scanning methods and for being played back from the magnetic tape using helical scanning methods. The second under signal is generated in such way that line-comb filtering can be used during playback to separate color-under signal and second under signal each from the composite signal despite their frequency spectra being at least partially overlapping in the composite signal.
    Type: Grant
    Filed: May 11, 1993
    Date of Patent: March 19, 1996
    Assignee: SamSung Electronics Co., Ltd.
    Inventors: Christopher H. Strolle, Chandrakant B. Patel, Werner F. Wedam, Raymond Schnitzler, Hermann J. Weckenbrock, Jung-Wan Ko, Jong-Kwung Yun, Allen L. Limberg
  • Patent number: 5500686
    Abstract: A filter for motion adaptive Y/C separation, which is capable of obtaining image of high resolution and little picture quality degradation in the case where an image is switched from static one to motion one or vice-versa, is provided with a filter for extracting Y signal outputting Y signal and a filter for extracting C signal outputting C signal, by detecting whether image is motion one or static one by a motion detecting unit, and when motion image is detected, by detecting partially interframe correlation or correlation in three fields, and according to the detection result, by adaptively switching a plurality of processings for extracting intraframe Y signal and a plurality of processings for extracting intraframe C signal.
    Type: Grant
    Filed: June 7, 1994
    Date of Patent: March 19, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Noriyuki Yamaguchi, Takuji Kurashita, Mitsuru Ishizuka, Junko Kijima, Masaharu Yao
  • Patent number: 5500687
    Abstract: A chrominance signal can be separated from a composite color television signal without misdetection in correlation detection even when the chrominance signal level is small by calculating vertical correlation values, comparing them with the threshold value corresponding to the chrominance signal level and judging if there is correlation or not. A chrominance signal separating apparatus includes a cascade connection of delay devices, where each delay device delays an input signal by 1H period. Comb filters separate a luminance signal and a chrominance signal from the composite color television signal by inputting two signals from the input and the output of each delay device which have a 1H period time difference. The output of one of the delay devices is regarded as a reference signal. A correlation detecting circuit calculates correlation values between the reference signal and a signal at the vertical vicinity of the reference signal on the screen.
    Type: Grant
    Filed: October 21, 1994
    Date of Patent: March 19, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Takahisa Hatano, Yoshihisa Nishigori
  • Patent number: 5486929
    Abstract: A system and method for recording video signals onto analog magnetic tape, and for the playback of those recorded signals. Such a system includes a digital luminance signal generator, a first digital chrominance signal, and a second digital chrominance signal compatible with a predetermined composite television signal standard. The chrominance signals are sample rate reduced by a sample rate reduction circuit, and then all three signals are multiplexed to generate a digital time division multiplexed video signal. This signal is frequency modulated, and then converted to an analog signal for recording onto an analog magnetic tape. This process is reversed for the playback of prerecorded signals. The signals recorded by and recovered by the present invention should be free of most artifacts related to composite television signal recording, have increased dynamic range, and have noise immunity comparable to other FM recording methods. Performance should also be independent of the type of magnetic tape used.
    Type: Grant
    Filed: September 3, 1993
    Date of Patent: January 23, 1996
    Assignee: Apple Computer, Inc.
    Inventor: Lawrence F. Heyl
  • Patent number: 5412481
    Abstract: A video recording/playback system includes in its recording electronics time-base correctors both for luma signal and for color-under signal, the time-base corrector for luma signal being used to facilitate comb filtering and the time-base corrector for chroma signal being used to maintain luma/chroma tracking during recording. The video recording/playback system includes in its playback electronics time-base correctors both for played-back luma signal and for played-back color-under signal, the time-base corrector for played-back luma signal being used to facilitate comb filtering and the time-base corrector for played-back chroma signal being used to maintain luma/chroma tracking during playback. With appropriate switching, the same pair of time-base correctors can be used in both the recording and the playback electronics of a video recording/playback system.
    Type: Grant
    Filed: February 24, 1992
    Date of Patent: May 2, 1995
    Assignee: SamSung Electronics Co., Ltd.
    Inventors: Jung W. Ko, Alvin R. Balaban, Christopher H. Strolle
  • Patent number: 5404180
    Abstract: A waveform shaping apparatus in which no unrequired waveform shaping operation is performed even if its sensitivity is enhanced is provided. A signal (A) to be shaped in waveform is delayed by delay circuits (1 and 2) to produce signals (B and C). The signals (A, B and C) are applied to an original correction signal generating means (200a) and a control signal generating means (100a) to produce original correction signals (Ka and Kb), and control signals (Ha and Hb), respectively. A control circuit (13) selects the original correction signals (Ka and Kb), or a value "0" in accordance with the control signals (Ha and Hb) to generate a quasi-correction signal (L). The signal (L) is multiplied by a specified coefficient in a coefficient multiplier (14) to produce a correction signal (M), and the correction signal (M) is added to the signal (B) in an adder (5) to obtain an output signal (N) which has been shaped in waveform.
    Type: Grant
    Filed: March 30, 1993
    Date of Patent: April 4, 1995
    Assignees: Mitsubishi Electric Engineering Company Limited, Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tooru Kitano, Tsutomu Kawano
  • Patent number: 5394197
    Abstract: A chrominance signal processing apparatus, where a chrominance subcarrier and a low-band converting chrominance subcarder are formed, uses a common oscillating signal to form the low-band converting chrominance subcarrier. The low-band converting chrominance signal processing apparatus includes an oscillator for producing an oscillating signal having a predetermined frequency, a chrominance subcarder generator receiving the oscillating signal to produce a chrominance subcarrier, a chrominance demodulator demodulating the chrominance signal incorporated in a composite video signal, a chrominance subcarrier generator receiving the oscillating signal to produce the low-band converting chrominance subcarrier, and a chrominance modulator receiving the chrominance signal demodulated in the chrominance demodulator and the low-band converting chrominance subcarrier to produce the low-band converting chrominance signal.
    Type: Grant
    Filed: November 29, 1993
    Date of Patent: February 28, 1995
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Yong-je Kim
  • Patent number: 5373326
    Abstract: A signal from an input terminal (1) is supplied to a video signal processing circuit (2) which derives a carrier chrominance signal. The carrier chrominance signal is supplied through a low-pass filter (3) to an A/D converter circuit (4). A signal converted by the A/D converter circuit (4) is supplied to a bandpass filter (5) which limits the band of the chrominance signal. A signal from the bandpass filter (5) is supplied to a decoder circuit (6) which alternately derives color difference signals (R-Y) and (B-Y). The signal from the decoder circuit (6) is supplied to a decimation filter (7) which effects a decimation. The signal thus decimated is supplied to a multiplexer (8) and thereby generated as 2-bit series data. A signal from the multiplexer (8) is supplied to a CNR (chroma noise reducer) circuit (9). Thus, the number of bits can be reduced without reducing the number of lines of a chroma signal and data gradation.
    Type: Grant
    Filed: March 30, 1993
    Date of Patent: December 13, 1994
    Assignee: Sony Corporation
    Inventors: Satoshi Nojima, Toshitaka Senuma
  • Patent number: 5335069
    Abstract: A signal processing system is disclosed in which the image resolution is improved by extending the horizontal frequency bands of separated luminance and chrominance signals and compensating the contour of an input image signal, the frequency band of the input chrominance signal is extended by the chrominance signal processing part, and by the extension of frequency band, the transition time of the high frequency components of the image signal is reduced for the high frequency image signal processing and reducing the short data processing time.
    Type: Grant
    Filed: January 28, 1992
    Date of Patent: August 2, 1994
    Assignee: SamSung Electronics Co., Ltd.
    Inventor: Jung H. Kim