Patents by Inventor Hoang Nhu

Hoang Nhu 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).

  • Publication number: 20050186926
    Abstract: Aspects of the method and system for rejecting single sided leakage into an amplitude modulated channel may comprise an AM demodulator for demodulating a received composite broadcast signal's control channel to generate an amplitude modulated (AM) component. A PM demodulator may demodulate a received composite broadcast signal's control channel to generate a phase modulated (PM) component. At least one subtractor may subtract an AM leakage component and a PM leakage component contributed by the single sided leakage in the received composite broadcast signal's control channel. The system may comprise at least one of each of AM and PM bandpass filters and envelope detectors that filter and detect envelopes of the AM and PM components at 982.5 Hz and 922.5 Hz.
    Type: Application
    Filed: July 2, 2004
    Publication date: August 25, 2005
    Inventor: Hoang Nhu
  • Publication number: 20050047603
    Abstract: A Japanese BTSC audio broadcast signal has three modes of transmission: mono, stereo, or dual mono. The control channel centering at 3.5 fH is one of the three channels in the J-BTSC signal, and contains information to indicate to the decoder which one of the three modes the audio transmission is in. The present invention uses a bandpass filter directly in the AM band, followed by envelope filtering and a decision circuit. Therefore, the need for AM demodulation and AM carrier detection is eliminated.
    Type: Application
    Filed: August 15, 2003
    Publication date: March 3, 2005
    Inventor: Hoang Nhu
  • Publication number: 20050036626
    Abstract: When processing a Japanese BTSC transmission, a main channel and a sub channel are processed separately. Because more components and steps are used to process the sub channel, processing the sub channel takes longer than the main channel. Therefore, a delay is inserted into the main channel. This delay is equal to the sum of the delays resulting from sub channel processing, less the delay pre-inserted into the main channel by a broadcaster. In an embodiment, the delay inserted is 42 samples. The processed main channel and sub channel are used together so as to produce left and right audio signals. All filters are designed to be very flat in the passband with steep rejection in the stop band; filters with the best phase linearity are chosen to allow good phase compensation via simple sample-delay insertion. This results in optimal stereo separation at the L and R decoded outputs.
    Type: Application
    Filed: August 15, 2003
    Publication date: February 17, 2005
    Inventor: Hoang Nhu
  • Publication number: 20050036357
    Abstract: A digital signal processor having a programmable address generator. In an embodiment, the programmable address generator enables an execution unit of the digital signal processor to perform register addressing, indirect addressing, and immediate addressing in response to a single arithmetic instruction. The digital signal processor is useful for implementing, for example, reprogrammable decoders and digital filters. In one embodiment, the digital signal processor is used to implement a US/Japan BTSC decoder.
    Type: Application
    Filed: August 15, 2003
    Publication date: February 17, 2005
    Inventors: Hoang Nhu, Jeffrey Bauch
  • Publication number: 20050036074
    Abstract: Provided is a method and system for implementing a digital interface to a BTSC decoder for analog television stereo audio signals. An exemplary system includes an I/F demodulator configured to (i) receive analog I/F signals and (ii) convert the received I/F signals to digital samples. These digital samples are input to a digital signal processor (DSP) for BTSC decoding into Left & Right audio outputs. This digital interface allows optimal stereo reparation between Left & Right outputs without the use of any signal level correction circuit.
    Type: Application
    Filed: August 25, 2003
    Publication date: February 17, 2005
    Inventor: Hoang Nhu
  • Publication number: 20050035887
    Abstract: Methods and systems for sample rate conversion convert a sampled signal to a higher data rate signal. Conversion pulses are received, having a conversion rate that is higher than the sample rate of the sampled signal. Sample points are then reconstructed from the sampled signal, in real time, on either side of a conversion pulse. An interpolation is performed between the reconstructed sample points, at the time of the conversion pulse. The interpolation results are outputted in real time. The process is repeated for additional conversion pulses. The outputted interpolated amplitudes form the higher data rate signal having a data rate equal to the conversion rate. Sample rate conversion is thus performed in real time according to the higher data rate clock, rather than with fixed ratios. As a result, when the higher data rate clock is affected by, for example, jitter or other frequency variations, the higher data rate samples immediately track the lower data rate samples.
    Type: Application
    Filed: August 15, 2003
    Publication date: February 17, 2005
    Inventor: Hoang Nhu
  • Publication number: 20050028220
    Abstract: A television on a chip (TVOC) system that provides a cost effective approach for providing television functionality on a single integrated circuit chip is disclosed. A TVOC includes the functionality necessary to receive and display television signals in a variety of input and output formats. A TVOC can be used in set-top boxes for cable and satellite television, or directly within a television. All functionality provided can be provided on a single integrated circuit. TVOC includes a data transport module, an IF demodulator, a digital audio engine, an analog audio engine, a digital video engine, and an analog video engine. The TVOC also includes three sets of interfaces including output interfaces, control interfaces and ancillary interfaces. Further features and embodiments provide enhanced functionality and increased efficiencies.
    Type: Application
    Filed: March 3, 2004
    Publication date: February 3, 2005
    Applicant: Broadcom Corporation
    Inventors: David Baer, Jeff Tingley, Aleksandr Movshovich, Brad Grossman, Brian Schoner, Chengfuh Tang, Chuck Monahan, Darren Neuman, David Wu, Francis Cheung, Greg Kranawetter, Hoang Nhu, Hsien-Chih Tseng, Iue-Shuenn Chen, James Sweet, Jeffrey Bauch, Keith Klingler, Patrick Law, Rajesh Mamidwar, Dan Simon, Sang Tran, Shawn Johnson, Steven Jaffe, Thu Nguyen, Ut Nguyen, Yao-Hua Tseng, Brad Delanghe, Ben Giese, Jason Demas, Lakshman Ramakrishnan, Sandeep Bhatia, Guang-Ting Shih, Tracy Denk
  • Patent number: 6741746
    Abstract: A method and apparatus for manipulating digitized images stored as variable length encoded bitstreams such as JPEG format in a manner that reduces memory and processor resource requirements. A prescan means sequentially decompresses the bitstream to identify the location of encoded pixel image areas. Designated ones of these locations are recorded or stored in a prescan table. After the prescan operation has been performed on the image, image manipulations such as rotating, cropping, and zooming can be performed on a selected portion of the image by directly accessing only the encoded pixel image areas to be manipulated, without the need to sequentially decode and store all the encoded image areas in order to locate the ones of interest.
    Type: Grant
    Filed: February 8, 2002
    Date of Patent: May 25, 2004
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Yoav Epstein, Kirkpatrick William Norton, Hoang Nhu
  • Publication number: 20030161477
    Abstract: A system and method are disclosed for performing digital multi-channel decoding of a BTSC composite audio signal. Each subsequent stage of the digital multi-channel decoding process is performed at the lowest sampling rate that yields acceptable performance for that stage. Analog-to-digital conversion of the composite audio signal is performed first to generate a composite digital audio signal. After analog-to-digital conversion, all signal processing may be performed in the digital domain. The composite digital audio signal is digitally filtered to frequency compensate for variations caused by previous stages of processing, including IF demodulation. Digital channel demodulation and filtering are performed to isolate single channels of the composite digital audio signal such as SAP, L−R, and L+R channels.
    Type: Application
    Filed: February 26, 2002
    Publication date: August 28, 2003
    Inventors: David Chaohua Wu, Hoang Nhu, Russ Lambert, Alexander G. MacInnis, Ronald Crochiere
  • Publication number: 20020085767
    Abstract: A method and apparatus for manipulating digitized images stored as variable length encoded bitstreams such as JPEG format in a manner that reduces memory and processor resource requirements. A prescan means sequentially decompresses the bitstream to identify the location of encoded pixel image areas. Designated ones of these locations are recorded or stored in a prescan table. After the prescan operation has been performed on the image, image manipulations such as rotating, cropping, and zooming can be performed on a selected portion of the image by directly accessing only the encoded pixel image areas to be manipulated, without the need to sequentially decode and store all the encoded image areas in order to locate the ones of interest.
    Type: Application
    Filed: February 8, 2002
    Publication date: July 4, 2002
    Inventors: Yoav Epstein, Kirkpatrick William Norton, Hoang Nhu
  • Patent number: 6381371
    Abstract: A method and apparatus for manipulating digitized images stored as variable length encoded bitstreams such as JPEG format in a manner that reduces memory and processor resource requirements. A prescan means sequentially decompresses the bitstream to identify the location of encoded pixel image areas. Designated ones of these locations are recorded or stored in a prescan table. After the prescan operation has been performed on the image, image manipulations such as rotating, cropping, and zooming can be performed on a selected portion of the image by directly accessing only the encoded pixel image areas to be manipulated, without the need to sequentially decode and store all the encoded image areas in order to locate the ones of interest.
    Type: Grant
    Filed: March 17, 1999
    Date of Patent: April 30, 2002
    Assignee: Hewlett-Packard Company
    Inventors: Yoav Epstein, Kirkpatrick William Norton, Hoang Nhu
  • Patent number: 5848224
    Abstract: A color copier machine includes a conventional image scanner for scanning successive swaths of an original document into an image memory and a conventional high quality four-color inkjet printing mechanism for printing each swath as an array of pixels each covered with up to two types of ink (black, or one primary color, or a secondary color combining two primary colors) and an optional color overprint mode in which the blackest pixels may be covered with op to three types of ink (black and one color or three colors).
    Type: Grant
    Filed: September 26, 1996
    Date of Patent: December 8, 1998
    Assignee: Hewlett-Packard Company
    Inventor: Hoang Nhu
  • Patent number: 5771338
    Abstract: A color copier machine includes a conventional image scanner for scanning successive swaths of an original document into an image memory and a conventional high quality four-color inkjet printing mechanism for printing each swath as an array of pixels each covered with up to three types of ink (black and one color or three colors). A monotone image is scanned only once and subsequent copies are printed from the half toned data stored in the image memory. The first copy is printed while the scanner is scanning, with each 8-bit pixel in the scanned image being printed and stored as a 1-bit (on or off) pixel (in the half-tone image. Print time for subsequent copies is less than that required for scanning/printing the first copy because in at least the black-only printing mode of a typical inkjet printer, the time required to scan and process a single swath is more than the time required to print that swath.
    Type: Grant
    Filed: September 26, 1996
    Date of Patent: June 23, 1998
    Assignee: Hewlett-Packard Company
    Inventor: Hoang Nhu