Patents by Inventor Weider Peter Chang

Weider Peter Chang has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9049408
    Abstract: A method of color processing determines whether a pixel color is within at least one range of predetermined colors corresponding to a viewer expected color. If so, the method altering the pixel color to better approximate the viewer expected color. For detection of skin tones determining whether the pixel color is within a range of predetermined colors includes discounting an illuminant of the pixel color. The viewer expected colors are preferably skin tone, grass green and sky blue. The saturation level of grass green and sky blue are enhanced and that of skin tones are suppressed. The saturation s is limited based upon lightness J and hue h to convert to an allowable RGB color format range.
    Type: Grant
    Filed: September 4, 2007
    Date of Patent: June 2, 2015
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Shereef Shehata, Weider Peter Chang
  • Patent number: 8619190
    Abstract: Film mode detection with bad edit detection used in de-interlacing video includes use of combing artifact detection in both 3-2 pull down detection and 2-2 pull down detection. Further, combing artifact detection uses only two field memories by accumulation of partial field statistics for comparisons.
    Type: Grant
    Filed: September 7, 2007
    Date of Patent: December 31, 2013
    Assignee: Texas Instruments Incorporated
    Inventors: Fan Zhai, Weider Peter Chang
  • Patent number: 8588474
    Abstract: A method for motion detection is provided that includes determining a first motion measure for a pixel based on differences between first neighboring pixels of the pixel, determining a detail measure for the pixel, wherein the detail measure is indicative of an amount of detail in second neighboring pixels of the pixel, adapting a first coring threshold and a first gain of a first transfer function based on the detail measure, and using the adapted first transfer function to map the first motion measure to a first motion parameter.
    Type: Grant
    Filed: July 11, 2011
    Date of Patent: November 19, 2013
    Assignee: Texas Instruments Incorporated
    Inventors: Ramesh M Chandrasekaran, Fan Zhai, Weider Peter Chang
  • Patent number: 8582032
    Abstract: Motion detection in interlaced video fields, as useful in de-interlacing, includes spatial-temporal maximum filtering, temporal IIR filtering dependent upon spatial-temporal variance, and spatial variance dependent moving-still interpolation blending factor.
    Type: Grant
    Filed: September 7, 2007
    Date of Patent: November 12, 2013
    Assignee: Texas Instruments Incorporated
    Inventors: Fan Zhai, Weider Peter Chang
  • Patent number: 8547481
    Abstract: This invention is a preprocessor apparatus and method algorithm facilitating black bar detection in video frames or fields. The preprocessing marks a sharp discontinuity between pixels a predetermined distance apart on each line. On first detection of this discontinuity the location and pixel value is stored. The location and pixel value is also stored for the last discontinuity in the line. This data enables software to detect top horizontal bars, bottom horizontal bars, left vertical bars and right vertical bars.
    Type: Grant
    Filed: December 20, 2010
    Date of Patent: October 1, 2013
    Assignee: Texas Instruments Incorporated
    Inventors: Paul M. Look, Masaki Kato, Weider Peter Chang
  • Publication number: 20130100349
    Abstract: This invention is a preprocessor apparatus and method algorithm facilitating black bar detection in video frames or fields. The preprocessing marks a sharp discontinuity between pixels a predetermined distance apart on each line. On first detection of this discontinuity the location and pixel value is stored. The location and pixel value is also stored for the last discontinuity in the line. This data enables software to detect top horizontal bars, bottom horizontal bars, left vertical bars and right vertical bars.
    Type: Application
    Filed: December 20, 2010
    Publication date: April 25, 2013
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Paul M. Look, Masaki Kato, Weider Peter Chang
  • Publication number: 20120008834
    Abstract: A method for motion detection is provided that includes determining a first motion measure for a pixel based on differences between first neighboring pixels of the pixel, determining a detail measure for the pixel, wherein the detail measure is indicative of an amount of detail in second neighboring pixels of the pixel, adapting a first coring threshold and a first gain of a first transfer function based on the detail measure, and using the adapted first transfer function to map the first motion measure to a first motion parameter.
    Type: Application
    Filed: July 11, 2011
    Publication date: January 12, 2012
    Inventors: Ramesh M. Chandrasekaran, Fan Zhai, Weider Peter Chang
  • Patent number: 7933469
    Abstract: Digital video contrast enhancement and skin tone correction by conversion to CIECAM02 color space with lightness transformation and a skin tone probability density function of hue and saturation.
    Type: Grant
    Filed: August 28, 2007
    Date of Patent: April 26, 2011
    Assignee: Texas Instruments Incorporated
    Inventors: Shereef Shehata, Weider Peter Chang
  • Patent number: 7532257
    Abstract: Base band compensation for an IF stage in a television provides significant advantages over compensation applied to the composite signal. Each base band color difference signal is filtered to obtain cross-talk elements, which are then applied to the opposite channel to eliminate the cross-talk components from the color difference signal channels. The compensation technique is applicable to IF stages generally, including those based on SAW filters. High and low gain compensation of the cross-talk compensated signals may also be performed to reduce distortion in the compensated signals. The base band compensation tends to reduce or eliminate visual artifacts in a television image, especially where sharp contrast transitions occur in the image.
    Type: Grant
    Filed: September 7, 2005
    Date of Patent: May 12, 2009
    Assignee: Texas Instruments Incorporated
    Inventors: Weider Peter Chang, Karl Hertzian Renner, Shereef Shehata
  • Patent number: 7511769
    Abstract: A system to reduce noise includes a noise measurement device that provides a measure of noise associated with a digital input video signal. A noise reduction filter provides a noise-reduced digital output video signal corresponding to the luma and chroma of the digital input video signal. The noise reduction filter has a parameter that varies on a pixel basis for the component of the digital input video signal as a function of the measure of noise. The range and sensitivity of the noise reduction can be user programmable.
    Type: Grant
    Filed: April 19, 2005
    Date of Patent: March 31, 2009
    Assignee: Texas Instruments Incorporated
    Inventors: Karl Hertzian Renner, Shereef Shehata, Jason Meiners, Weider Peter Chang
  • Patent number: 7468763
    Abstract: System and method for an all-digital audio receiver for a BTSC MTS audio signal or other composite signal that is FM modulated. A preferred embodiment comprises a digital FM demodulator for receiving an analog to digital quantized SIF signal and performing demodulation and outputting a composite audio signal, and a digital audio processor for decomposing the composite audio signal into at least the SAP, stereo and monaural signals for audio reproduction. In a preferred embodiment, the digital audio processor is a programmable digital signal processor. In a preferred embodiment, the digital FM demodulator and the digital audio processor are implemented as an integrated circuit. Methods for processing the audio signal using the digital processors of the invention are provided.
    Type: Grant
    Filed: August 9, 2005
    Date of Patent: December 23, 2008
    Assignee: Texas Instruments Incorporated
    Inventors: Feng Ying, Karl Hertzian Renner, Weider Peter Chang, Shereef Shehata, Viet Dinh, Xiaodong Wu, Walter Heinrich Demmer
  • Patent number: 7453525
    Abstract: Systems and methods are provided for detecting motion within a composite video signal. A first chroma difference element compares an in-phase chroma component of the composite video signal to a delayed representation of the in-phase chroma component to produce a first chroma difference value for a given pixel. A second chroma difference element compares a quadrature chroma component of the composite video signal to a delayed representation of the quadrature chroma component to produce a second chroma difference value for the pixel. A parameter mapping component maps the first and second difference values to respective first and second motion parameters that indicates the degree of change in the chroma properties of the pixel. A parameter selector determines a composite motion parameter for the pixel from the first and second motion parameters.
    Type: Grant
    Filed: May 24, 2005
    Date of Patent: November 18, 2008
    Assignee: Texas Instruments Incorporated
    Inventors: Karl Renner, Weider Peter Chang, Ramesh M. Chandrasekaran
  • Patent number: 7443454
    Abstract: A method for treating inter-frame motion in a series of consecutive signal frames of a composite video signal includes the steps of, for an evaluation pixel position in each frame of a test frame-set including three successive signal frames: (a) determining whether there is at least a predetermined difference in chroma component or in luma component signals at the evaluation pixel; (b) if in step (a) there is not a predetermined difference in chroma component signals or in luma component signals, determining whether a first and third frame of the test frame-set are substantially identical; (c) determining whether at least a first predetermined number of the luma or chroma component signals in the test frame-set present at least one false color; and (d) determining whether at least a second predetermined number of high frequency luma component signals exist in the test frame-set.
    Type: Grant
    Filed: October 1, 2005
    Date of Patent: October 28, 2008
    Assignee: Texas Instruments Incorporated
    Inventors: Ramesh M. Chandrasekaran, Weider Peter Chang, Karl Renner
  • Patent number: 7355655
    Abstract: Systems and method are provided for luma-chroma separation. A demodulator system demodulates a composite video signal to produce at least two baseband chroma signals. A given baseband chroma signal contains chroma information for one of a plurality of video frames comprising the composite signal. A three-dimensional (3-D) comb filter removes luma information from a given baseband chroma signal by combining sets of at least two baseband chroma signals to form a 3-D filtered baseband signal.
    Type: Grant
    Filed: May 24, 2005
    Date of Patent: April 8, 2008
    Assignee: Texas Instruments Incorporated
    Inventors: Weider Peter Chang, Karl Renner, Ramesh M. Chandrasekaran, Steven Clynes, Jason Meiners
  • Patent number: 7349033
    Abstract: Systems and methods are provided for correcting color phase error in a video decoder system. A demodulator system demodulates the composite input signal and the at least one delayed signal to produce sets of baseband chroma components based on a phase correction value. Color phase correction logic determines the phase correction value for the demodulator system based upon characteristics of the baseband chroma components associated with a series of at least two consecutive frames.
    Type: Grant
    Filed: May 23, 2005
    Date of Patent: March 25, 2008
    Assignee: Texas Instruments Incorporated
    Inventors: Weider Peter Chang, Ramesh M. Chandrasekaran
  • Publication number: 20080062307
    Abstract: Film mode detection with bad edit detection used in de-interlacing video includes use of combing artifact detection in both 3-2 pull down detection and 2-2 pull down detection. Further, combing artifact detection uses only two field memories by accumulation of partial field statistics for comparisons.
    Type: Application
    Filed: September 7, 2007
    Publication date: March 13, 2008
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Fan Zhai, Weider Peter Chang
  • Publication number: 20080062308
    Abstract: Film mode detection with bad edit detection used in de-interlacing video includes use of combing artifact detection in both 3-2 pull down detection and 2-2 pull down detection. Further, combing artifact detection uses only two field memories by accumulation of partial field statistics for comparisons.
    Type: Application
    Filed: September 7, 2007
    Publication date: March 13, 2008
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Fan Zhai, Weider Peter Chang
  • Patent number: 7173668
    Abstract: The present invention discloses a horizontal sync detector circuit (10) comprising a filter portion (12), an equilibrium accumulator portion (14) coupled to the filter portion (12), a horizontal sync detector portion (16) coupled to the filter portion (12) and to the equilibrium accumulator portion (14), and an output logic portion (18) coupled to the horizontal sync detector portion (16), the output logic portion (18) adapted to produce a phase error (116) based on a combination of a coarse phase error (108) and a fine phase error (112).
    Type: Grant
    Filed: July 18, 2003
    Date of Patent: February 6, 2007
    Assignee: Texas Instruments Incorporated
    Inventors: Karl Renner, Walter Heinrich Demmer, Jason M. Meiners, Weider Peter Chang, Airong Amy Zhang
  • Patent number: 6459457
    Abstract: A color comb filter (46), video decoder (40) and method for separating chroma (U,V) and luma (Y) signals from a composite video signal (41). The comb filter (46) includes circuitry (48) for generating color filter selections for filtering a chroma video signal (41) and control logic (62) for determining the filter selections based on color boundary properties of the chroma video signal (U,V). The video decoder (40) includes a comb filter (46), a demodulator (42), low pass filter (44), a remodulator (48) and a subtractor (50). The filtered, remodulated chroma signal (Uout,Vout) is subtracted from the composite video signal (41) to produce a luma signal absent hanging dots and false colors.
    Type: Grant
    Filed: December 21, 1999
    Date of Patent: October 1, 2002
    Assignee: Texas Instruments Incorporated
    Inventors: Karl Renner, Weider Peter Chang, Walter Demmer
  • Patent number: 6366327
    Abstract: A technique for detecting three modes of video input signal and outputting a vertical sync signal based on the input signal. In a first mode, a standard video signal is received and a line counter is used to decode and output the vertical sync. In a second mode where a non-standard signal is received, line counter cannot be used, but a vertical sync is detected and output. In a third mode, no video input signal is received, yet a vertical sync is output in free-running mode so that a blank screen is displayed.
    Type: Grant
    Filed: July 30, 1998
    Date of Patent: April 2, 2002
    Assignee: Texas Instruments Incorporated
    Inventors: Karl H. Renner, Weider Peter Chang