Patents by Inventor Ke-Chiang Chu

Ke-Chiang Chu 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: 7929778
    Abstract: In a digital signal processing system, a method for selecting a transform function to apply to an input signal based on characteristics of the signal, and for self-adjusting criteria which are used in selecting a transform function to apply to a subsequent signal. Characteristics are obtained from the signal. The characteristics are compared to adjustable criteria which are used in selecting a transform function. Differing criteria are maintained for the different selectable transform functions. A record is maintained of transform functions selected and the particular characteristics that caused the selection. Based on the ability of a transform function to minimally define the coded signal, an inverse transform function is selected to decode the signal. The criteria used in selecting a transform function to apply to a subsequent signal are adjusted based on a quality measure of the decoded signal and the record of selected transform functions.
    Type: Grant
    Filed: August 10, 2009
    Date of Patent: April 19, 2011
    Assignee: Apple Inc.
    Inventors: Hsi-Jung Wu, Yu Tina Tian, Jian Lu, Ke-Chiang Chu
  • Publication number: 20100067792
    Abstract: In a digital signal processing system, a method for selecting a transform function to apply to an input signal based on characteristics of the signal, and for self-adjusting criteria which are used in selecting a transform function to apply to a subsequent signal. Characteristics are obtained from the signal. The characteristics are compared to adjustable criteria which are used in selecting a transform function. Differing criteria are maintained for the different selectable transform functions. A record is maintained of transform functions selected and the particular characteristics that caused the selection. Based on the ability of a transform function to minimally define the coded signal, an inverse transform function is selected to decode the signal. The criteria used in selecting a transform function to apply to a subsequent signal are adjusted based on a quality measure of the decoded signal and the record of selected transform functions.
    Type: Application
    Filed: August 10, 2009
    Publication date: March 18, 2010
    Inventors: Hsi-Jung Wu, Yu Tina Tian, Jian Lu, Ke-Chiang Chu
  • Patent number: 7577306
    Abstract: In a digital signal processing system, a method for selecting a transform function to apply to an input signal based on characteristics of the signal, and for self-adjusting criteria which are used in selecting a transform function to apply to a subsequent signal. Characteristics are obtained from the signal. The characteristics are compared to adjustable criteria which are used in selecting a transform function. Differing criteria are maintained for the different selectable transform functions. A record is maintained of transform functions selected and the particular characteristics that caused the selection. Based on the ability of a transform function to minimally define the coded signal, an inverse transform function is selected to decode the signal. The criteria used in selecting a transform function to apply to a subsequent signal are adjusted based on a quality measure of the decoded signal and the record of selected transform functions.
    Type: Grant
    Filed: May 16, 2006
    Date of Patent: August 18, 2009
    Assignee: Apple Inc.
    Inventors: Hsi-Jung Wu, Yu Tina Tian, Jian Lu, Ke-Chiang Chu
  • Publication number: 20080112647
    Abstract: Systems and methods for resizing data that provides higher quality results while using fewer resources than traditional methods. In one embodiment disclosed herein, a nearest neighborhood technique is used to compute data that can be used to generate target data. The resizing method is ideal for use in mobile devices, where video and audio data may need to be resized or resampled, but memory and processing power are scarce.
    Type: Application
    Filed: November 15, 2006
    Publication date: May 15, 2008
    Inventor: Ke-Chiang Chu
  • Publication number: 20070283237
    Abstract: The present invention relates generally to multimedia playback devices, and more particularly to systems and methods for multimedia content distribution and playback. In accordance with one preferred embodiment, a method for distributing multimedia content to a playback system includes the steps of converting the multimedia content into an intermediate format, loading the converted multimedia content into the playback system, and converting the multimedia content from the intermediate format to a format supported by the playback system, wherein the intermediate format and the format supported by the playback system are different.
    Type: Application
    Filed: June 2, 2006
    Publication date: December 6, 2007
    Inventors: Ke-Chiang Chu, James P. Tann, Johnathan P. Tann
  • Publication number: 20060210181
    Abstract: In a digital signal processing system, a method for selecting a transform function to apply to an input signal based on characteristics of the signal, and for self-adjusting criteria which are used in selecting a transform function to apply to a subsequent signal. Characteristics are obtained from the signal. The characteristics are compared to adjustable criteria which are used in selecting a transform function. Differing criteria are maintained for the different selectable transform functions. A record is maintained of transform functions selected and the particular characteristics that caused the selection. Based on the ability of a transform function to minimally define the coded signal, an inverse transform function is selected to decode the signal. The criteria used in selecting a transform function to apply to a subsequent signal are adjusted based on a quality measure of the decoded signal and the record of selected transform functions.
    Type: Application
    Filed: May 16, 2006
    Publication date: September 21, 2006
    Inventors: Hsi-Jung Wu, Yu Tian, Jian Lu, Ke-Chiang Chu
  • Patent number: 7092580
    Abstract: A system and method using edge processing to remove blocking artifacts comprises an edge processor having an image converter for building an edge representation of a received image, a statistics analyzer for compiling a histogram containing edge intensities of the edge representation, a reference calculator for using the histogram to compute reference values corresponding to the blocking artifacts and an artifact remover for identifying and removing the blocking artifacts using the computed reference values.
    Type: Grant
    Filed: May 17, 2004
    Date of Patent: August 15, 2006
    Assignee: Apple Computer, Inc.
    Inventors: Ke-Chiang Chu, Jian Lu, Yu Tina Tian, Hsi-Jung Wu
  • Patent number: 7079695
    Abstract: In a digital signal processing system, a method for selecting a transform function to apply to an input signal based on characteristics of the signal, and for self-adjusting criteria which are used in selecting a transform function to apply to a subsequent signal. Characteristics are obtained from the signal. The characteristics are compared to adjustable criteria which are used in selecting a transform function. Differing criteria are maintained for the different selectable transform functions. A record is maintained of transform functions selected and the particular characteristics that caused the selection. Based on the ability of a transform function to minimally define the coded signal, an inverse transform function is selected to decode the signal. The criteria used in selecting a transform function to apply to a subsequent signal are adjusted based on a quality measure of the decoded signal and the record of selected transform functions.
    Type: Grant
    Filed: August 7, 2003
    Date of Patent: July 18, 2006
    Assignee: Apple Computer, Inc.
    Inventors: Hsi-Jung Wu, Yu Tina Tian, Jian Lu, Ke-Chiang Chu
  • Publication number: 20040264800
    Abstract: A system and method using edge processing to remove blocking artifacts comprises an edge processor having an image converter for building an edge representation of a received image, a statistics analyzer for compiling a histogram containing edge intensities of the edge representation, a reference calculator for using the histogram to compute reference values corresponding to the blocking artifacts and an artifact remover for identifying and removing the blocking artifacts using the computed reference values.
    Type: Application
    Filed: May 17, 2004
    Publication date: December 30, 2004
    Inventors: Ke-Chiang Chu, Jian Lu, Yu Tina Tian, Hsi-Jung Wu
  • Patent number: 6798918
    Abstract: A system and method using edge processing to remove blocking artifacts comprises an edge processor having an image converter for building an edge representation of a received image, a statistics analyzer for compiling a histogram containing edge intensities of the edge representation, a reference calculator for using the histogram to compute reference values corresponding to the blocking artifacts and an artifact remover for identifying and removing the blocking artifacts using the computed reference values.
    Type: Grant
    Filed: April 17, 2002
    Date of Patent: September 28, 2004
    Assignee: Apple Computer, Inc.
    Inventors: Ke-Chiang Chu, Jian Lu, Yu Tina Tian, Hsi-Jung Wu
  • Patent number: 6795740
    Abstract: The invention is a method, apparatus and computer readable program for eliminating overflow and underflow by re-adjusting or rectifying the audio levels of an audio signal in those portions where overflow/underflow occurs. In a first preferred embodiment a single stage scale down solution is provided in starting and end points of the overflow/underflow areas in the audio signal are detected, and a number of discrete sampling points along the audio signal curve between these two points are adjusted by a predetermined multiplier in order to reduce the positive level (in the case of overflow) or negative level (in the case of underflow) of each discrete sampling point. Using the single stage scale down solution of the present invention, a new audio signal is created having no overflow/underflow, yet maintaining the former generally smooth shape of the audio signal waveform and signal characteristics, without completely clipping the audio levels.
    Type: Grant
    Filed: March 1, 2000
    Date of Patent: September 21, 2004
    Assignee: Apple Computer, Inc.
    Inventors: Ke Chiang Chu, Hong Kaura, James Peter Hoddie
  • Publication number: 20040032988
    Abstract: In a digital signal processing system, a method for selecting a transform function to apply to an input signal based on characteristics of the signal, and for self-adjusting criteria which are used in selecting a transform function to apply to a subsequent signal. Characteristics are obtained from the signal. The characteristics are compared to adjustable criteria which are used in selecting a transform function. Differing criteria are maintained for the different selectable transform functions. A record is maintained of transform functions selected and the particular characteristics that caused the selection. Based on the ability of a transform function to minimally define the coded signal, an inverse transform function is selected to decode the signal. The criteria used in selecting a transform function to apply to a subsequent signal are adjusted based on a quality measure of the decoded signal and the record of selected transform functions.
    Type: Application
    Filed: August 7, 2003
    Publication date: February 19, 2004
    Inventors: Hsi-Jung Wu, Yu Tina Tian, Jian Lu, Ke-Chiang Chu
  • Publication number: 20030187528
    Abstract: The present invention provides signal processing method and apparatus for audio special effect processing on an input signal. The signal processing system of the invention eliminates the need for FFT and inverse FFT operations from an audio signal decoding system by providing au audio special effect processing routine before a frequency-to-time conversion. The audio special effect processing routine may perform equalization and/or base boost operations. After an input signal is processed by the, the modified input signal is converted to a time-domain signal by a frequency-to-time conversion unit so that audible sound may be generated based on the time-domain signal. The frequency-to-time conversion unit may comprise an MDCT (modified discrete cosine transform) routine and comprise a synthesizer filter.
    Type: Application
    Filed: April 2, 2002
    Publication date: October 2, 2003
    Inventors: Ke-Chiang Chu, Krishna Sherigara Mala, Sree Ramesh Karukonda
  • Patent number: 6618509
    Abstract: In a digital signal processing system, a method for selecting a transform function to apply to an input signal based on characteristics of the signal, and for self-adjusting criteria which are used in selecting a transform function to apply to a subsequent signal. Characteristics are obtained from the signal. The characteristics are compared to adjustable criteria which are used in selecting a transform function. Differing criteria are maintained for the different selectable transform functions. A record is maintained of transform functions selected and the particular characteristics that caused the selection. Based on the ability of a transform function to minimally define the coded signal, an inverse transform function is selected to decode the signal. The criteria used in selecting a transform function to apply to a subsequent signal are adjusted based on a quality measure of the decoded signal and the record of selected transform functions.
    Type: Grant
    Filed: April 9, 2001
    Date of Patent: September 9, 2003
    Assignee: Apple Computer, Inc.
    Inventors: Hsi-Jung Wu, Yu Tina Tian, Jian Lu, Ke-Chiang Chu
  • Patent number: 6531969
    Abstract: A filter system and method are provided that is particular applicable to the resampling of a signal, such as a digital audio signal. The filtering method in accordance with the invention may use a nearest neighbor strategy to reduce the complexity and cost of the filter without reducing the precision of the resampling.
    Type: Grant
    Filed: May 2, 2001
    Date of Patent: March 11, 2003
    Assignee: Portalplayer, Inc.
    Inventor: Ke-Chiang Chu
  • Publication number: 20020184277
    Abstract: A filter system and method are provided that is particular applicable to the resampling of a signal, such as a digital audio signal. The filtering method in accordance with the invention may use a nearest neighbor strategy to reduce the complexity and cost of the filter without reducing the precision of the resampling.
    Type: Application
    Filed: May 2, 2001
    Publication date: December 5, 2002
    Inventor: Ke-Chiang Chu
  • Publication number: 20020110284
    Abstract: A system and method using edge processing to remove blocking artifacts comprises an edge processor having an image converter for building an edge representation of a received image, a statistics analyzer for compiling a histogram containing edge intensities of the edge representation, a reference calculator for using the histogram to compute reference values corresponding to the blocking artifacts and an artifact remover for identifying and removing the blocking artifacts using the computed reference values.
    Type: Application
    Filed: April 17, 2002
    Publication date: August 15, 2002
    Inventors: Ke-Chiang Chu, Jian Lu, Yu Tina Tian, Hsi-Jung Wu
  • Patent number: 6389177
    Abstract: A system and method using edge processing to remove blocking artifacts comprises an edge processor having an image converter for building an edge representation of a received image, a statistics analyzer for compiling a histogram containing edge intensities of the edge representation, a reference calculator for using the histogram to compute reference values corresponding to the blocking artifacts and an artifact remover for identifying and removing the blocking artifacts using the computed reference values.
    Type: Grant
    Filed: July 2, 1996
    Date of Patent: May 14, 2002
    Assignee: Apple Computer, Inc.
    Inventors: Ke-Chiang Chu, Jian Lu, Yu Tina Tian, Hsi-Jung Wu
  • Publication number: 20010033139
    Abstract: In a digital signal processing system, a method for selecting a transform function to apply to an input signal based on characteristics of the signal, and for self-adjusting criteria which are used in selecting a transform function to apply to a subsequent signal. Characteristics are obtained from the signal. The characteristics are compared to adjustable criteria which are used in selecting a transform function. Differing criteria are maintained for the different selectable transform functions. A record is maintained of transform functions selected and the particular characteristics that caused the selection. Based on the ability of a transform function to minimally define the coded signal, an inverse transform function is selected to decode the signal. The criteria used in selecting a transform function to apply to a subsequent signal are adjusted based on a quality measure of the decoded signal and the record of selected transform functions.
    Type: Application
    Filed: April 9, 2001
    Publication date: October 25, 2001
    Inventors: Hsi-Jung Wu, Yu Tina Tian, Jian Lu, Ke-Chiang Chu
  • Patent number: 6229917
    Abstract: In a digital signal processing system, a method for selecting a transform function to apply to an input signal based on characteristics of the signal, and for self-adjusting criteria which are used in selecting a transform function to apply to a subsequent signal. Characteristics are obtained from the signal. The characteristics are compared to adjustable criteria which are used in selecting a transform function. Differing criteria are maintained for the different selectable transform functions. A record is maintained of transform functions selected and the particular characteristics that caused the selection. Based on the ability of a transform function to minimally define the coded signal, an inverse transform function is selected to decode the signal. The criteria used in selecting a transform function to apply to a subsequent signal are adjusted based on a quality measure of the decoded signal and the record of selected transform functions.
    Type: Grant
    Filed: September 14, 1999
    Date of Patent: May 8, 2001
    Assignee: Apple Computer, Inc.
    Inventors: Hsi-Jung Wu, Yu Tina Tian, Jian Lu, Ke-Chiang Chu