Patents by Inventor Wai Wu

Wai Wu 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: 20050152449
    Abstract: A method and apparatus for processing a bitstream in a digital video transcoder is described. In one example, an adjustment factor is determined that relates a number of bits representing a selected frame defined by the bitstream to a target number of bits for the selected frame. An average spatial activity value among sets of video data is associated with the selected frame. A spatial activity value for a selected set of the sets of video data is determined. A normalized spatial, activity value for the selected set of frequency video data is then computed in response to the average spatial activity value, the spatial activity value, and a function of the adjustment factor. Target bit reduction for each of the sets of video data may be computed using a function of the normalized spatial activity value and the adjustment factor.
    Type: Application
    Filed: January 12, 2004
    Publication date: July 14, 2005
    Inventors: Robert Nemiroff, Siu-Wai Wu
  • Publication number: 20050120733
    Abstract: A heat pump includes a first and second heat exchanger, a scroll compressor and a flash tank in fluid communication. The flash tank includes an inlet fluidly coupled to the heat exchangers to receive liquid refrigerant. Furthermore, the flash tank includes a first outlet fluidly coupled to the first and second heat exchangers and a second outlet fluidly coupled to the scroll compressor. The first outlet is operable to deliver sub-cooled-liquid refrigerant to the heat exchangers while the second outlet is operable to deliver vaporized refrigerant to the scroll compressor. An expansion valve is further provided and is operable to selectively open and close the inlet by a float device. The float device is operable to control an amount of liquid refrigerant disposed within the flash tank by regulating an amount of liquid refrigerant entering the flash tank via the inlet.
    Type: Application
    Filed: June 23, 2004
    Publication date: June 9, 2005
    Inventors: John Healy, Man Wai Wu, Simon Wang
  • Patent number: 6904094
    Abstract: An efficient processing system, such as for transcoding video data. In an embodiment that is suitable for single or multiple processor embodiments, a processing mode is set for each input video frame, e.g., as a full transcode mode, which uses motion compensation, a requantization mode, which avoids motion compensation, or a bypass mode. The processing mode selection is based on a number of processing cycles that are available to process a frame, and an expected processing requirement of the frame. The bypass or requantization modes are selected to avoid a buffer overflow of the processor.
    Type: Grant
    Filed: September 20, 2000
    Date of Patent: June 7, 2005
    Assignee: General Instrument Corporation
    Inventors: Vincent Liu, Robert S. Nemiroff, Siu-Wai Wu, Ajay Luthra, Limin Wang
  • Patent number: 6892952
    Abstract: A water control module is provided that monitors water temperature in plumbing, such as shower plumbing, and receives certain input commands from a user. The water control module may, in one example, control shower water flow temperature to preferential temperature values. Control of shower water flow temperature is accomplished by receiving user input of desired water temperature on a user interface, sensing current water temperature in the plumbing, and processing the user inputs and sensed water temperature values to control water delivery temperature. In another example, the water control module may provide a display screen with numerical and/or graphical features to inform the user of desired and/or measured temperature values.
    Type: Grant
    Filed: December 27, 2002
    Date of Patent: May 17, 2005
    Assignee: Ewig Industries Co., Ltd.
    Inventors: Chee Ann Chang, Kai Wai Wu, Wai Man Yuen
  • Publication number: 20050094965
    Abstract: The present invention provides improvements of the rate control method during the transitions at the splice point. In one embodiment, black frames and/or mute audio frames are inserted at the splice point.
    Type: Application
    Filed: September 7, 2004
    Publication date: May 5, 2005
    Inventors: Jing Chen, Robert Nemiroff, Siu-Wai Wu
  • Publication number: 20050041689
    Abstract: An efficient statistical remultiplexer for processing a number of channels that include video data. In one aspect, transcoding of the video data is delayed while statistical information is obtained from the data. Bit rate need parameters for the data are determined based on the statistical information, and the video data is transcoded based on the respective bit rate need parameters following the delay. In another aspect, a transcoding bit rate for video frames is updated a plurality of times at successive intervals to allow a closer monitoring of the bit rate. Minimum and maximum bounds for the transcoding bit rate, e.g., for buffer overflow and underflow protection, are also updated in each interval.
    Type: Application
    Filed: September 20, 2004
    Publication date: February 24, 2005
    Applicant: General Instrument Corporation
    Inventors: Siu-Wai Wu, Robert Nemiroff, Vincent Liu, Ajay Luthra
  • Publication number: 20050036549
    Abstract: The present invention discloses a system and method for adaptive selection of scanning modes based on the content of the input image sequence. In one embodiment, two encoders are employed. A first encoder receives the input image sequence and encodes each frame of the image sequence using at least two different scanning modes, e.g., zigzag scanning mode or alternative scanning mode in accordance with the MPEG-2 standard or the like. Specifically, different portions of each frame will be scanned using different scanning modes. This first encoding provides look-ahead information so that a second encoder is able to assign DCT quantized coefficients in a more efficient scanning order, thereby reducing encoding bits and/or improving the picture quality.
    Type: Application
    Filed: July 9, 2004
    Publication date: February 17, 2005
    Inventors: Yong He, Siu-Wai Wu
  • Patent number: 6847656
    Abstract: An efficient statistical remultiplexer for processing a number of channels that include video data. In one aspect, transcoding of the video data is delayed while statistical information is obtained from the data. Bit rate need parameters for the data are determined based on the statistical information, and the video data is transcoded based on the respective bit rate need parameters following the delay. In another aspect, a transcoding bit rate for video frames is updated a plurality of times at successive intervals to allow a closer monitoring of the bit rate. Minimum and maximum bounds for the transcoding bit rate, e.g., for buffer overflow and underflow protection, are also updated in each interval. In another aspect, the pre-transcoding quantization scales of the macroblocks in a frame are scaled to provide corresponding new quantization scales for transcoding based on a ratio of a pre-transcoding amount of data in the frame and a target, post-transcoding amount of data for the frame.
    Type: Grant
    Filed: September 25, 2000
    Date of Patent: January 25, 2005
    Assignee: General Instrument Corporation
    Inventors: Siu-Wai Wu, Robert S. Nemiroff, Vincent Liu, Ajay Luthra
  • Publication number: 20040233998
    Abstract: The present invention provides methods and apparatus for improving video quality in statistical multiplexing. For each encoding channel in a statistical multiplexer, a respective bit rate need parameter is calculated for encoding of a current frame in that encoding channel. A video buffering verifier level (VBV_Fullness) available to each encoding channel is also calculated. It is then determined whether the VBV_Fullness available to each encoding channel is sufficient for encoding the current frame of that encoding channel based on an initial complexity estimate for that current frame. In the event that the VBV_Fullness is determined to be sufficient, the current frame is encoded using the need parameter. In the event that the VBV_Fullness is determined to be insufficient, the need parameter is scaled by an adaptive panic multiplier and the current frame is encoded using the scaled need parameter.
    Type: Application
    Filed: May 19, 2003
    Publication date: November 25, 2004
    Applicant: General Instrument Corporation
    Inventors: Siu-Wai Wu, Yong He
  • Patent number: 6804301
    Abstract: The invention relates to an improved system and method for encoding digital images within frames for digital television transmission. Every anchor frame in a first pass encoder is encoded as a P-frame. Groups of macroblocks, such as slices in the P-frame, are alternately encoded as I-slices and P-slices. This allows both I and P encoding complexity to be computed in a single pass, without having to encode the same frame twice. Accordingly, the I-frame decision can be made at a second pass encoder instead of at the first pass encoder, thus taking advantage of a look-ahead pipeline architecture to more effectively align the I-frames with scene changes.
    Type: Grant
    Filed: August 15, 2001
    Date of Patent: October 12, 2004
    Assignee: General Instrument Corporation
    Inventors: Siu-Wai Wu, Vincent Liu
  • Publication number: 20040187504
    Abstract: A cooling system including a pulse-width modulated variable capacity compressor operable between on-cycles and off-cycles, and in electrical communication with the compressor and operable to respectively synchronize opening and closing thereof with on- and off-cycles of the compressor.
    Type: Application
    Filed: January 6, 2004
    Publication date: September 30, 2004
    Inventors: John Joseph Healy, Man Wai Wu, Mark Lai Yuen Ng, Hung M. Pham
  • Publication number: 20040100874
    Abstract: An electronic device with interchangeable faceplate assembly is described. The assembly provides a faceplate with a viewing region, an electronic device having a device housing for interfacing with the faceplate, and a means for coupling the faceplate to the device housing to define a front viewing panel for the electronic device. A number of faceplate configurations may be implemented for coupling with the device housing.
    Type: Application
    Filed: November 22, 2002
    Publication date: May 27, 2004
    Inventors: Chee Ann Chang, Kai Wai Wu, Wai Man Yuen
  • Publication number: 20040090996
    Abstract: The present invention provides methods and apparatus for statistical multiplexing of a large number of data streams. A plurality of encoders are associated with each first stage multiplexer. Bandwidth allocation among all encoders is controlled by a second stage multiplexer. A bandwidth request message is communicated from each the encoders to the second stage multiplexer. The second stage multiplexer allocates available bandwidth based on the bandwidth request messages. The second stage multiplexer then communicates an allocated bandwidth message to each encoder. Each encoder encodes a data stream in accordance with its allocated bandwidth to provide an encoded data stream. A plurality of the encoded data streams are multiplexed at each first stage multiplexer to provide a multiplexed data stream at a constant data rate. The second stage multiplexer mutiplexes the multiplexed data streams from the first stage multiplexers to provide a multiplexed transport stream.
    Type: Application
    Filed: October 30, 2003
    Publication date: May 13, 2004
    Applicant: General Instrument Corporation
    Inventors: Siu-Wai Wu, Keith J. Kelley, Vinh Tran
  • Patent number: 6731685
    Abstract: A statistical multiplexer for coding and multiplexing multiple channels of digital television data, or multiple panels of HDTV digital television data. A bit rate need parameter is determined for each encoder in a stat mux group by scaling the complexities of previous pictures of the same and different picture types. Scaling factors based on an activity level, motion estimation score, and number of pictures of a certain type in a GOP, may be used. Moreover, the scaling factors may be bounded based on a linear or non-linear operator to prevent large variations in the factors. An encoding bit rate is allocated to each channel based on its need parameter.
    Type: Grant
    Filed: September 20, 2000
    Date of Patent: May 4, 2004
    Assignee: General Instrument Corporation
    Inventors: Vincent Liu, Siu-Wai Wu, Hanson On, Robert S. Nemiroff, Michael Casteloes, Jing Yang Chen, Rebecca Lam
  • Patent number: 6731684
    Abstract: A method and apparatus are provided for detecting scene changes between successive fields in a digital television signal. I-frames, which start new GOPs, are aligned with scene changes. In a preprocessing stage (205, 210), the change in the sum of pixel differences between consecutive odd fields, or consecutive even fields, is calculated for every consecutive input field. A scene change is detected when a large positive value in the change of sum is followed by a large negative value therein. A decision of which picture type to use is not made until a final encoding stage (225, 235). I-frames can be inhibited when an encoder buffer level is too high. A counter resets the scene change indication to avoid a perpetual scene change state for transitions from still to motion. In film mode, the MPEG-recommended frame-based encoding is deactivated when a scene change occurred on a field boundary (e.g., when there is no redundant field in the picture).
    Type: Grant
    Filed: March 29, 2001
    Date of Patent: May 4, 2004
    Assignee: General Instrument Corporation
    Inventor: Siu-Wai Wu
  • Patent number: 6724825
    Abstract: A system for providing an accurate time reference for multiple input and output digital video signals of a transcoder that is particularly suited for use with MPEG data. The multiple streams are synchronized with a single master system time clock at the transcoder. Timing data from the master clock is compared to timing data from packets that are input to the transcoder to determine an offset. In particular, timing data, such as a program clock reference (PCR) field, is recovered from packets of different channels that are input to the transcoder. For each channel, timing data is then provided for packets that are output from the transcoder based on the offset and timing data of the master clock at the respective output times. In particular, the adjusted timing data is determined as a sum of the offset and an associated hardware error, less a delay (PcrSysDly) associated with the transcoder, which includes a lookahead delay and a buffer delay.
    Type: Grant
    Filed: September 22, 2000
    Date of Patent: April 20, 2004
    Assignee: General Instrument Corporation
    Inventors: Robert S. Nemiroff, Vincent Liu, Siu-Wai Wu
  • Publication number: 20040066710
    Abstract: Alarm clock systems, methods and AC power sockets employ voice synthesis technology to control functions without physical manipulation. One or more processors control clocking and alarm functions within a modular unit. A speech recognition processor digitizes and processes audible commands. A microphone senses the audible commands. The alarm clock may be programmed by the user to recognize and associate user-chosen audible commands with specific alarm functions, for example, the alarm clock system may be programmed to activate the alarm function in response to the command “Turn alarm on”. Audible prompts generated by a voice synthesizer and icons shown on a display of the alarm clock system assist the user in programming and setting. Voice command data is stored in an internal memory of the alarm clock system.
    Type: Application
    Filed: September 25, 2003
    Publication date: April 8, 2004
    Inventors: Wai Man Yuen, Kai Wai Wu
  • Patent number: 6694060
    Abstract: A controller allocates a bit size for a current frame in a group of pictures of a first compression-encoded digital video signal that is to be spliced following transmission of the group of pictures with a second compression-encoded digital video signal. The signals are spliced after a predetermined switching time. The spliced signals are buffered by a decoder buffer and then decoded by a decoder. When the second signal has a variable bit-encoding rate and the current frame is not decoded until after the predetermined switching time, the maximum bit size is determined in accordance with an estimate of the decoder buffer fullness at the predetermined switching time. When the second signal has a predetermined maximum variable bit-encoding rate and the current frame is not decoded until after the predetermined switching time, the minimum bit size is determined in accordance with the predetermined maximum bit-encoding rate of the second signal.
    Type: Grant
    Filed: December 21, 2000
    Date of Patent: February 17, 2004
    Assignee: General Instrument Corporation
    Inventors: Vincent Liu, Jingyang Chen, Siu-Wai Wu
  • Publication number: 20040007003
    Abstract: A system including an evaporator, a variable capacity compressor coupled in fluid communication with the evaporator, a condenser coupled in fluid communication between the compressor and the evaporator, an expansion valve disposed intermediate the condenser and the evaporator, and an isolation valve disposed intermediate the condenser and the expansion valve is provided. The isolation valve is in communication with the compressor to respectively synchronize opening and closing thereof with on- and off-cycles of the compressor to prohibit migration of liquid refrigerant. In an alternative embodiment, first and second check valves are respectively associated with the compressor and the condenser for prohibiting reverse migration of refrigerant during the off-cycle.
    Type: Application
    Filed: July 15, 2002
    Publication date: January 15, 2004
    Inventors: John Joseph Healy, Man Wai Wu, Mark Lai Yuen Ng, Hung M. Pham
  • Patent number: D485192
    Type: Grant
    Filed: December 17, 2002
    Date of Patent: January 13, 2004
    Assignee: Ewig Industries Co., Ltd.
    Inventors: Chee Ann Chang, Kai Wai Wu, Wai Man Yuen