Patents by Inventor Dihong Tian

Dihong Tian 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: 8135071
    Abstract: A method, and apparatus, and logic encoded in one or more computer-readable tangible medium to carry out a method. The method is to code an ordered sequence of quantized transform coefficients of a block of image data using a hybrid coding method that includes determining a breakpoint location in the sequence between a low-frequency region and a high-frequency region; coding the low-frequency region using a selected low-frequency variable length coding method; coding the high-frequency region using a selected high-frequency variable length coding method; and coding the location of the breakpoint. The breakpoint location is determined as a function of properties of neighboring blocks such that little if any information needs to be sent to a decoder about the breakpoint of a block or multi-block partition, and the decoder can use the properties of neighboring blocks to determine the breakpoint used to code a to-be-decoded sequence or sequences of a block or a multi-block partition.
    Type: Grant
    Filed: March 15, 2007
    Date of Patent: March 13, 2012
    Assignee: Cisco Technology, Inc.
    Inventors: Dihong Tian, Wen-hsiung Chen, Pi Sheng Chang, John A. Toebes
  • Publication number: 20120057636
    Abstract: A method is provided in one example and includes receiving an input video, and identifying values of pixels from noise associated with a current video image within the video input. The method also includes creating a skip-reference video image associated with the identified pixel values, and comparing a portion of the current video image to the skip-reference video image. The method also includes determining a macroblock associated with the current video image to be skipped before an encoding operation occurs.
    Type: Application
    Filed: September 8, 2010
    Publication date: March 8, 2012
    Inventors: Dihong Tian, Joseph T. Friel, Andrew P. Weir
  • Patent number: 8126062
    Abstract: A method, and apparatus, and logic encoded in one or more computer-readable tangible medium to carry out a method. The method is to code a plurality of ordered sequences of quantized transform coefficients of a corresponding plurality of blocks of image data using a hybrid coding method that includes determining a breakpoint location in the sequence between a low frequency region and a high frequency region; coding the low-frequency region using a selected low-frequency variable length coding method; coding the high-frequency region using a selected high-frequency variable length coding method; and coding the location of the breakpoint. The plurality of blocks include adjacent blocks and form a multi-block partition. The breakpoint location is determined as a function of the sequences of the multi-block partition such that different multi-block partitions can have different breakpoints.
    Type: Grant
    Filed: March 15, 2007
    Date of Patent: February 28, 2012
    Assignee: Cisco Technology, Inc.
    Inventors: Dihong Tian, Wen-hsiung Chen, Pi Sheng Chang, John A. Toebes
  • Patent number: 8121427
    Abstract: A method, and apparatus, and logic encoded in one or more computer-readable tangible medium to carry out a method of determining a breakpoint position in an ordered sequence of quantized transform coefficients of a block of image data for a hybrid variable length coding the ordered sequence. The breakpoint location in the sequence is between a low-frequency region and a high-frequency region. The hybrid variable length coding method includes coding the low-frequency region using a selected low-frequency variable length coding method; coding the high-frequency region using a selected high-frequency variable length coding method; and coding the position in the sequence of the breakpoint. The breakpoint location is determining uses a relatively simple and fast method based on pre-defined cost criteria. A method is included that instead of coding the breakpoint separately, codes the breakpoint jointly with coefficient events.
    Type: Grant
    Filed: December 20, 2007
    Date of Patent: February 21, 2012
    Assignee: Cisco Technology, Inc.
    Inventors: Dihong Tian, Pi Sheng Chang, Wen-hsiung Chen
  • Patent number: 8086076
    Abstract: An apparatus, a method, and a computer-readable medium having instructions encoded thereon that when executed cause a method to be carried out. The method includes dividing at least a portion of a picture of a video stream into parts of blocks, and processing the parts in parallel by a plurality of interconnected processors. The processing of a respective part by its respective processor includes determining block-level temporal difference features. Each processor also performs coding functions on its respective part of the picture. The method also includes block-level processing using the block-level temporal difference features to determine which blocks in the picture are likely to be that of a face, the block-level processing being at the granularity of at least a block. In one version, the processing in each processor includes edge detection and color segmentation to determine block-level edge features including block-level color-segmented edge features that are then used in the block level processing.
    Type: Grant
    Filed: February 14, 2008
    Date of Patent: December 27, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: Dihong Tian, Joseph T. Friel, J. William Mauchly, Wen-hsiung Chen
  • Publication number: 20110285825
    Abstract: A method that includes capturing depth information associated with a first field of view of a depth camera. The depth information is represented by a first plurality of depth pixels. The method also includes capturing color information associated with a second field of view of a video camera that substantially overlaps with the first field of view of the depth camera. The color information is represented by a second plurality of color pixels. The method further includes enhancing color information represented by at least one color pixel of the second plurality of color pixels to generate an enhanced image. The enhanced image adjusts an exposure characteristic of the color information captured by the video camera. The at least one color pixel is enhanced based on depth information represented by at least one corresponding depth pixel of the first plurality of depth pixels.
    Type: Application
    Filed: May 20, 2010
    Publication date: November 24, 2011
    Applicant: Cisco Technology, Inc.
    Inventors: Dihong Tian, J. William Mauchly, Joseph T. Friel
  • Patent number: 8041131
    Abstract: A coding method, apparatus, and medium with software encoded thereon to implement a coding method. The coding method includes encoding cluster of consecutive non-zero-valued coefficients, the encoding of a cluster including jointly encoding joint events that each are defined by at least two parameters: the number of zero-valued coefficients preceding the cluster, and the number of non-zero-valued coefficients in the cluster. The encoding of the cluster also includes encoding a parameter indicative of the number of amplitude-1 trailing non-zero-valued coefficients in the cluster, in one version with the parameter indicative of the number of trailing amplitude-1 coefficients part of the joint events such that the coding is according to a 3-dimensional joint variable length coding table. The method further includes encoding the amplitudes of the non-zero-valued coefficients that are not encoded by the joint encoding, e.g., encoding the amplitudes of the other than the trailing amplitude-1 coefficients.
    Type: Grant
    Filed: February 13, 2008
    Date of Patent: October 18, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: Junlin Li, Ghassan AlRegib, Wen-hsiung Chen, Dihong Tian, Pi Sheng Chang
  • Patent number: 8036471
    Abstract: A coding method, apparatus, and medium with software encoded thereon to implement a coding method. The coding method includes jointly encoding joint events that each are defined by a cluster of consecutive non-zero-valued coefficients, each joint event defined by three parameters: the number of zero-valued coefficients preceding the cluster, the number of non-zero-valued coefficients in the cluster, and an indication of which trailing coefficients up to a maximum number of M trailing coefficients have amplitude greater than 1, with the coding using a 3-dimensional joint VLC table. The method further includes encoding the amplitude of the non-zero-valued trailing coefficients that have amplitude greater than 1 encoding the amplitude of any remaining non-zero-valued coefficients in the clusters that have more than M non-zero-valued coefficients.
    Type: Grant
    Filed: February 13, 2008
    Date of Patent: October 11, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: Junlin Li, Ghassan AlRegib, Wen-hsiung Chen, Dihong Tian, Pi Sheng Chang
  • Publication number: 20110228096
    Abstract: A method is provided in one example and includes receiving image data for a field of view associated with a display. The image data is used to generate a plurality of red green blue (RGB) frames. The method also includes emitting infrared energy onto the field of view in order to generate a plurality of infrared frames, the plurality of RGB frames and the plurality of infrared frames are generated by a single camera. The plurality of RGB frames can be combined with the plurality of infrared frames in order to generate a video data stream. In a more particular embodiment, the emitting of the infrared energy is synchronized with the camera such that the infrared energy is emitted onto the field of view at one half of an existing frame rate of the camera.
    Type: Application
    Filed: March 18, 2010
    Publication date: September 22, 2011
    Inventors: Joseph T. Friel, J. William Mauchly, Dihong Tian
  • Patent number: 7949195
    Abstract: A method, and apparatus, and logic encoded in one or more computer-readable tangible medium to carry out a method. The method is to code an ordered sequence of quantized transform coefficients of a block of image data using a hybrid coding method that includes determining a breakpoint location in the sequence between a low frequency region and a high frequency region; coding the low-frequency region using a selected low-frequency variable length coding method; coding the high-frequency region using a selected high-frequency variable length coding method; and coding the location of the breakpoint. The breakpoint location is determined as a function of the sequence such that different sequences can have different breakpoints.
    Type: Grant
    Filed: March 15, 2007
    Date of Patent: May 24, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: Dihong Tian, Pi Sheng Chang, Wen-hsiung Chen
  • Publication number: 20110080946
    Abstract: A coding method, apparatus, and storage media with instructions to carry out a method. The method operates on an ordered series of transform coefficients of a block of image data, and for a fixed quantization method, and includes quantizing and encoding the ordered series to form a coded bitstream. The quantizing and encoding uses one or more variable length code (VLC) mappings. The quantizing includes quantizing to have amplitude-1 at least one coefficient that would be quantized by the fixed quantization method to have zero amplitude, quantizing to have zero amplitude at least one coefficient that would be quantized by the fixed quantization method to have amplitude-1, and using the fixed quantization method to quantize any coefficient that is quantized by the fixed quantization method not to have zero amplitude, amplitude-1, or amplitude-2.
    Type: Application
    Filed: October 6, 2009
    Publication date: April 7, 2011
    Inventors: Junlin Li, Dihong Tian, Wen-hsiung Chen, Yian Xu
  • Publication number: 20100246680
    Abstract: A video coder includes a forward coder and a reconstruction module determining a motion compensated predicted picture from one or more previously decoded pictures in a multi-picture store. The reconstruction module includes a reference picture predictor that uses only previously decoded pictures to determine one or more predicted reference pictures. The predicted reference picture(s) are used for motion compensated prediction. The reference picture predictor may include optical flow analysis that uses a current decoded picture and that may use one or more previously decoded pictures together with affine motion analysis and image warping to determine at least a portion of at least one of the reference pictures.
    Type: Application
    Filed: March 26, 2009
    Publication date: September 30, 2010
    Inventors: Dihong Tian, J. William Mauchly, Joseph T. Friel, Wen-hsiung Chen
  • Publication number: 20100208078
    Abstract: Techniques are provided to determine the horizontal gaze of a person from a video signal generated from viewing the person with at least one video camera. From the video signal, a head region of the person is detected and tracked. The dimensions and location of a sub-region within the head region is also detected and tracked from the video signal. An estimate of the horizontal gaze of the person is computed from a relative position of the sub-region within the head region.
    Type: Application
    Filed: February 17, 2009
    Publication date: August 19, 2010
    Applicant: Cisco Technology, Inc.
    Inventors: Dihong Tian, Joseph T. Friel, J. William Mauchly
  • Publication number: 20100202670
    Abstract: In one embodiment, an apparatus may receive at least one image in which multiple targets are represented. The apparatus may assign possible identities to the targets based on probabilities associated with the identities. The apparatus may base a probability of a target being one of the identities, at least in part, on an identity-specific context and on a conditional probability that the target is the identity given that each one of at least two other of the targets is another respective one of the identities. The identity-specific context may be information that relates to a determined identity. The apparatus may identify the targets based on the identities and on the probabilities associated with the identities.
    Type: Application
    Filed: February 9, 2009
    Publication date: August 12, 2010
    Applicant: Cisco Technology, Inc.
    Inventors: Dihong Tian, Wen-hsiung Chen
  • Publication number: 20100125768
    Abstract: Techniques are provided for video communication between multiple devices. Each of a plurality of video packets is designated as being part of a required reference frame that is subsequently to be used for a repair process. A stream of video packets that includes the packets for the required reference frame is transmitted from a source device over a communication medium for reception by a plurality of destination devices. A determination is made that at least one of the plurality of destination devices did not receive at least one packet of the required reference frame, and the at least one packet is retransmitted the at least one of the plurality of destination devices. When the retransmitted packet is received at the at least one destination device, it is decoded and stored without using it for generating a picture for display at the time that the at least one packet is received.
    Type: Application
    Filed: November 17, 2008
    Publication date: May 20, 2010
    Applicant: CISCO TECHNOLOGY, INC.
    Inventors: J. William Mauchly, Joseph T. Friel, Dihong Tian
  • Publication number: 20100119164
    Abstract: In an image generation and rendering system, a quality stamp indicative of image fidelity is embedded in image data units resulting from image data compression/encoding. At decoding, the image quality stamp is captured and when the decoded image is rendered, a fidelity indicator is displayed along with the image.
    Type: Application
    Filed: November 7, 2008
    Publication date: May 13, 2010
    Applicant: CISCO TECHNOLOGY, INC.
    Inventors: Dave M. Singhal, Wen-hsiung Chen, Dihong Tian
  • Publication number: 20100061225
    Abstract: A network-adaptive error recovery method for real-time video transmission based on sending repair frames preemptively with a frequency that is based on observed run-length of good frames and round trip time.
    Type: Application
    Filed: September 5, 2008
    Publication date: March 11, 2010
    Inventors: JOSEPH T. FRIEL, DIHONG TIAN, J. WILLIAM MAUCHLY, MAURICE BUTTIMER
  • Publication number: 20090324023
    Abstract: Techniques are provided to analyze video frames of a video signal in order to distinguish regions containing a face (and body torso) from regions that contain a relatively static background. The region containing the face is referred to as a foreground region. A current video frame is divided into a plurality of elements and the foreground regions and background regions are detected. The background regions of a subsequent video frame are detected/registered using the foreground regions of the current video frame. The foreground regions of the subsequent video frame are determined using the background regions of the current video frame as a temporal reference.
    Type: Application
    Filed: June 30, 2008
    Publication date: December 31, 2009
    Applicant: Cisco Technology, Inc.
    Inventors: Dihong Tian, Joseph T. Friel, J. William Mauchly, Maurice J. Buttimer, We-hsiung Chen
  • Publication number: 20090256901
    Abstract: A system and method for alerting participants in a videoconference that one or more participants are improperly framed by the videoconference camera is provided. An embodiment comprises a temporary self-view picture-in-picture image appearing when the number of faces detected by the videoconference camera changes. A face detection algorithm is used to determine when the number of faces being detected by the videoconference camera has changed. The self-view picture-in-picture image displays, for a duration of time, a representation of the image being captured by the videoconference camera, allowing participants who are not properly framed by the videoconference camera to adjust their position to that their faces are captured by the videoconference camera.
    Type: Application
    Filed: April 15, 2008
    Publication date: October 15, 2009
    Inventors: J. William Mauchly, Joseph T. Friel, Dihong Tian
  • Publication number: 20090238278
    Abstract: Particular embodiments generally relate to video compression. In one embodiment, a store of reference frames is provided in memory. The reference frames may be classified based on a plurality of classifiers. The classifiers may correspond to features that are found in the reference frame. A frame to encode is then received. The frame is analyzed to determine features found in the frame. As macroblocks in the frame are encoded, a macroblock is analyzed to determine which feature may be included in the macroblock. The feature is used to determine a classifier, which is used to determine a subset of the reference frames. The subset is then searched to determine a reference frame for the macroblock.
    Type: Application
    Filed: March 19, 2008
    Publication date: September 24, 2009
    Applicant: CISCO TECHNOLOGY, INC.
    Inventors: William Mauchly, Joseph T. Friel, Alan MacDonald, Dihong Tian, Wen-Hsiung Chen, Michael A. Arnao