Patents by Inventor Ka Lun Choi

Ka Lun Choi 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: 8929446
    Abstract: A combiner processing system and a method of operating the combiner processing system are disclosed. In one embodiment, the combiner processing system is utilized for a support layer processing in a bit-rate reduction system that separates video data into a main layer and a support layer with separated encodings for the two layers for bit-rate reduction and data transmission efficiency. Preferably, the combiner processing system for the support layer processing is capable of processing repeat patterns, small high frequency details, and textual information contained in one or more images. Furthermore, in one embodiment, the combiner processing system for the support layer processing provides a motion vector detection on a full image reconstruction, a non-linear quantization which retains both textual information and small high frequency details, utilization of full combination motion vectors, and a separate processing path for textual information with an internal bit-rate reduction unit.
    Type: Grant
    Filed: March 14, 2014
    Date of Patent: January 6, 2015
    Assignee: Faroudja Enterprises, Inc.
    Inventors: Yves Faroudja, Ka Lun Choi, Xu Dong
  • Patent number: 8831354
    Abstract: One or more systems and methods for edge-adaptive and recursive non-linear filtering of ringing effect on image or video data are disclosed in accordance with various embodiments of the invention. In one embodiment of the invention, a method for edge-adaptive and recursive non-linear filtering of ringing effect first involves detecting all edges within a process area of an image, including a direction of an edge slope and a value of an edge signal level. Then, if the process area is determined to be a “non-busy” area based on a “busyness” measure relative to empirically-defined threshold values, then an edge influence function subsequently determines whether to apply a de-ringing filter to a current pixel within the process area or not. Preferably, the de-ringing filter is edge-adaptive, non-linear, and recursive. The de-ringing filter can adjust the current pixel multiple times based on filter angles, adjacent pixels, and pixel transition levels.
    Type: Grant
    Filed: January 8, 2014
    Date of Patent: September 9, 2014
    Assignee: Faroudja Enterprises, Inc.
    Inventors: Yves Faroudja, Ka Lun Choi, Xu Dong
  • Patent number: 7038495
    Abstract: Provided is a circuit to convert input CMOS level signals having a predetermined duty cycle to CML level signals having a higher duty cycle. The circuit includes two differential transistor pairs connected together. The two differential pairs are constructed and arranged to use gates of the associated transistors as inputs to receive and combine a number of phase shifted CMOS input signals. The combined CMOS input signal are converted to CML level signals which are provided as circuit outputs.
    Type: Grant
    Filed: June 16, 2004
    Date of Patent: May 2, 2006
    Assignee: Broadcom Corporation
    Inventor: Ka Lun Choi
  • Patent number: 7034584
    Abstract: A frequency dividing circuit divides a master clock frequency by a non-integer factor to provide an output clock signal whose frequency is equal to the frequency of the master clock signal divided by that non-integer factor. In one embodiment, the circuit is operative to divide the master clock frequency by 2.5.
    Type: Grant
    Filed: March 10, 2005
    Date of Patent: April 25, 2006
    Assignee: Broadcom Corporation
    Inventors: Ka Lun Choi, Derek Hing Sang Tam
  • Patent number: 7005902
    Abstract: A charge pump circuit includes a high-swing transconductance amplifier. A high input swing transconductance is provided in a negative feedback loop of the charge pump circuit without an abrupt change in transconductance. The high-swing transconductance amplifier includes a transconductance cell and high-swing circuitry. The transconductance cell includes a current supply transistor, which provides current for transconductance while input voltages are within the operational range for the transconductance cell. When the input voltages increase so as to be outside of the operational range, the current source transistor enters into triode region of operation, and provides reduced current. The high-swing circuitry supplies the current in this case so that abrupt change in transconductance does not occur.
    Type: Grant
    Filed: February 18, 2005
    Date of Patent: February 28, 2006
    Assignee: Broadcom Corporation
    Inventor: Ka Lun Choi
  • Publication number: 20050156639
    Abstract: A frequency dividing circuit divides a master clock frequency by a non-integer factor to provide an output clock signal whose frequency is equal to the frequency of the master clock signal divided by that non-integer factor. In one embodiment, the circuit is operative to divide the master clock frequency by 2.5.
    Type: Application
    Filed: March 10, 2005
    Publication date: July 21, 2005
    Applicant: Broadcom Corporation
    Inventors: Ka Lun Choi, Derek Tam
  • Publication number: 20050146364
    Abstract: A charge pump circuit includes a high-swing transconductance amplifier. A high input swing transconductance is provided in a negative feedback loop of the charge pump circuit without an abrupt change in transconductance. The high-swing transconductance amplifier includes a transconductance cell and high-swing circuitry. The transconductance cell includes a current supply transistor, which provides current for transconductance while input voltages are within the operational range for the transconductance cell. When the input voltages increase so as to be outside of the operational range, the current source transistor enters into triode region of operation, and provides reduced current. The high-swing circuitry supplies the current in this case so that abrupt change in transconductance does not occur.
    Type: Application
    Filed: February 18, 2005
    Publication date: July 7, 2005
    Applicant: Broadcom Corporation
    Inventor: Ka Lun Choi
  • Patent number: 6882190
    Abstract: A frequency dividing circuit divides a master clock frequency by a non-integer factor to provide an output clock signal whose frequency is equal to the frequency of the master clock signal divided by that non-integer factor. In one embodiment, the circuit is operative to divide the master clock frequency by 2.5.
    Type: Grant
    Filed: February 2, 2004
    Date of Patent: April 19, 2005
    Assignee: Broadcom Corporation
    Inventors: Ka Lun Choi, Derek Hing Sang Tam
  • Patent number: 6873194
    Abstract: A charge pump circuit includes a high-swing transconductance amplifier. A high input swing transconductance is provided in a negative feedback loop of the charge pump circuit without an abrupt change in transconductance. The high-swing transconductance amplifier includes a transconductance cell and high-swing circuitry. The transconductance cell includes a current supply transistor, which provides current for transconductance while input voltages are within the operational range for the transconductance cell. When the input voltages increase so as to be outside of the operational range, the current source transistor enters into triode region of operation, and provides reduced current. The high-swing circuitry supplies the current in this case so that abrupt change in transconductance does not occur.
    Type: Grant
    Filed: February 20, 2004
    Date of Patent: March 29, 2005
    Assignee: Broadcom Corporation
    Inventor: Ka Lun Choi
  • Patent number: 6864723
    Abstract: A charge pump circuit includes a high-swing transconductance amplifier. A high input swing transconductance is provided in a negative feedback loop of the charge pump circuit without an abrupt change in transconductance. The high-swing transconductance amplifier includes a transconductance cell and high-swing circuitry. The transconductance cell includes a current supply transistor, which provides current for transconductance while input voltages are within the operational range for the transconductance cell. When the input voltages increase so as to be outside of the operational range, the current source transistor enters into triode region of operation, and provides reduced current. The high-swing circuitry supplies the current in this case so that abrupt change in transconductance does not occur.
    Type: Grant
    Filed: September 20, 2001
    Date of Patent: March 8, 2005
    Assignee: Broadcom Corporation
    Inventor: Ka Lun Choi
  • Publication number: 20040222822
    Abstract: Provided is a circuit to convert input CMOS level signals having a predetermined duty cycle to CML level signals having a higher duty cycle. The circuit includes two differential transistor pairs connected together. The two differential pairs are constructed and arranged to use gates of the associated transistors as inputs to receive and combine a number of phase shifted CMOS input signals. The combined CMOS input signal are converted to CML level signals which are provided as circuit outputs.
    Type: Application
    Filed: June 16, 2004
    Publication date: November 11, 2004
    Applicant: Broadcom Corporation
    Inventor: Ka Lun Choi
  • Patent number: 6794907
    Abstract: Provided is a circuit to convert input CMOS level signals having a predetermined duty cycle to CML level signals having a higher duty cycle. The circuit includes two differential transistor pairs connected together. The two differential pairs are constructed and arranged to use gates of the associated transistors as inputs to receive and combine a number of phase shifted CMOS input signals. The combined CMOS input signal are converted to CML level signals which are provided as circuit outputs.
    Type: Grant
    Filed: September 17, 2001
    Date of Patent: September 21, 2004
    Assignee: Broadcom Corporation
    Inventor: Ka Lun Choi
  • Publication number: 20040160249
    Abstract: A charge pump circuit includes a high-swing transconductance amplifier. A high input swing transconductance is provided in a negative feedback loop of the charge pump circuit without an abrupt change in transconductance. The high-swing transconductance amplifier includes a transconductance cell and high-swing circuitry. The transconductance cell includes a current supply transistor, which provides current for transconductance while input voltages are within the operational range for the transconductance cell. When the input voltages increase so as to be outside of the operational range, the current source transistor enters into triode region of operation, and provides reduced current. The high-swing circuitry supplies the current in this case so that abrupt change in transconductance does not occur.
    Type: Application
    Filed: February 20, 2004
    Publication date: August 19, 2004
    Applicant: Broadcom Corporation
    Inventor: Ka Lun Choi
  • Publication number: 20040150437
    Abstract: A frequency dividing circuit divides a master clock frequency by a non-integer factor to provide an output clock signal whose frequency is equal to the frequency of the master clock signal divided by that non-integer factor. In one embodiment, the circuit is operative to divide the master clock frequency by 2.5.
    Type: Application
    Filed: February 2, 2004
    Publication date: August 5, 2004
    Inventors: Ka Lun Choi, Derek Hing Sang Tam
  • Patent number: 6707327
    Abstract: A frequency dividing circuit divides a master clock frequency by a non-integer factor to provide an output clock signal whose frequency is equal to the frequency of the master clock signal divided by that non-integer factor. In one embodiment, the circuit is operative to divide the master clock frequency by 2.5.
    Type: Grant
    Filed: December 2, 2002
    Date of Patent: March 16, 2004
    Assignee: Broadcom Corporation
    Inventors: Ka Lun Choi, Derek Hing Sang Tam
  • Patent number: 6642753
    Abstract: A charge pump circuit includes a high-swing transconductance amplifier. A high input swing transconductance is provided in a negative feedback loop of the charge pump circuit without an abrupt change in transconductance. The high-swing transconductance amplifier includes a transconductance cell and high-swing circuitry. The transconductance cell includes a current supply transistor, which provides current for transconductance while input voltages are within the operational range for the transconductance cell. When the input voltages increase so as to be outside of the operational range, the current source transistor enters into triode region of operation, and provides reduced current. The high-swing circuitry supplies the current in this case so that abrupt change in transconductance does not occur.
    Type: Grant
    Filed: September 20, 2001
    Date of Patent: November 4, 2003
    Assignee: Broadcom Corporation
    Inventor: Ka Lun Choi
  • Publication number: 20030117187
    Abstract: A frequency dividing circuit divides a master clock frequency by a non-integer factor to provide an output clock signal whose frequency is equal to the frequency of the master clock signal divided by that non-integer factor. In one embodiment, the circuit is operative to divide the master clock frequency by 2.5.
    Type: Application
    Filed: December 2, 2002
    Publication date: June 26, 2003
    Applicant: Broadcom Corporation
    Inventors: Ka Lun Choi, Derek Hing Sang Tam
  • Patent number: 6570417
    Abstract: A frequency dividing circuit divides a master clock frequency by a non-integer factor to provide an output clock signal whose frequency is equal to the frequency of the master clock signal divided by that non-integer factor. In one embodiment, the circuit is operative to divide the master clock frequency by 2.5.
    Type: Grant
    Filed: October 22, 2001
    Date of Patent: May 27, 2003
    Assignee: Broadcom Corporation
    Inventors: Ka Lun Choi, Derek Hing Sang Tam
  • Publication number: 20020057117
    Abstract: A frequency dividing circuit divides a master clock frequency by a non-integer factor to provide an output clock signal whose frequency is equal to the frequency of the master clock signal divided by that non-integer factor. In one embodiment, the circuit is operative to divide the master clock frequency by 2.5.
    Type: Application
    Filed: October 22, 2001
    Publication date: May 16, 2002
    Inventors: Ka Lun Choi, Derek Hing Sang Tam
  • Publication number: 20020036538
    Abstract: A charge pump circuit includes a high-swing transconductance amplifier. A high input swing transconductance is provided in a negative feedback loop of the charge pump circuit without an abrupt change in transconductance. The high-swing transconductance amplifier includes a transconductance cell and high-swing circuitry. The transconductance cell includes a current supply transistor, which provides current for transconductance while input voltages are within the operational range for the transconductance cell. When the input voltages increase so as to be outside of the operational range, the current source transistor enters into triode region of operation, and provides reduced current. The high-swing circuitry supplies the current in this case so that abrupt change in transconductance does not occur.
    Type: Application
    Filed: September 20, 2001
    Publication date: March 28, 2002
    Inventor: Ka Lun Choi