Patents by Inventor Tihao Chiang

Tihao Chiang 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: 20040042549
    Abstract: A robust fine granularity scalability video encoding includes a base layer encoder and an enhancement layer encoder in which motion compensated difference images are generated by comparing an original image to predicted images at base layer and enhancement layer with motion compensation. Based on leaky and partial predictions, a high quality reference image is constructed at the enhancement layer to improve temporal prediction. In the construction of the high quality reference image, one parameter &bgr; controls the number of bitplanes of the enhancement layer difference coefficients used and another parameter &agr; controls the amount of predictive leak. A spatial scalability module allows the processed pictures at the base layer and the enhancement layer to have identical or different spatial resolutions.
    Type: Application
    Filed: August 27, 2002
    Publication date: March 4, 2004
    Inventors: Hsiang-Chun Huang, Chung-Neng Wang, Tihao Chiang, Hsueh-Ming Hang
  • Patent number: 6690833
    Abstract: A method and apparatus for selecting a quantizer scale for each macroblock within a frame to optimize the coding rate is presented. A quantizer scale is selected for each macroblock within each frame such that the target bit rate for the frame is achieved while maintaining a uniform visual quality over the entire frame.
    Type: Grant
    Filed: June 18, 1998
    Date of Patent: February 10, 2004
    Assignee: Sarnoff Corporation
    Inventors: Tihao Chiang, Hung-Ju Lee, Ya-Qin Zhang
  • Patent number: 6665872
    Abstract: When two or more different video streams a e compressed for concurrent transmission of multiple compressed video bitstreams over a single shared communication channel, control over both (1) the transmission of data over the shared channel and (2) the compression processing that generates the bitstreams is exercised taking into account the differing levels of latency required for the corresponding video applications. For example, interactive video games typically require lower latency than other video applications such as video streaming, web browsing, and electronic mail. A multiplexer and traffic controller takes these differing latency requirements, along with bandwidth and image fidelity requirements, into account when controlling both traffic flow and compression processing.
    Type: Grant
    Filed: January 5, 2000
    Date of Patent: December 16, 2003
    Assignee: Sarnoff Corporation
    Inventors: Ravi Krishnamurthy, Sriram Sethuraman, Xiaobing Lee, Tihao Chiang
  • Publication number: 20030202579
    Abstract: A method transcodes a compressed multi-layer video bitstream that includes a base layer bitstream and an enhancement layer bitstream. The base and enhancement layers are first partially decoded, and then the partially decoded signals are combined with a motion compensated signal yielding a combined signal. The combined signal is quantized into an output signal according to a quantization parameter, and the output signal is variable length encoded as a single layer bitstream. In a preprocessing step, the enhancement layer can be truncated according to rate control constraint, and the same constraints can also be used during the quantization.
    Type: Application
    Filed: April 24, 2002
    Publication date: October 30, 2003
    Inventors: Yao-Chung Lin, Chung-Neng Wang, Tihao Chiang, Anthony Vetro, Huifang Sun
  • Publication number: 20030123550
    Abstract: The present invention proposes a fast motion estimation using N-queen pixel decimation, whereby after a reference block and a block to be processed are selected in a video sequence, an N×N queens pattern is used for pixel decimation to perform block match, thereby obtaining a good enough block difference value. The present invention combines pixel decimation with fast motion estimation for search points reduction to achieve the object of simplifying computational complexity of motion estimation. Therefore, the present invention can sieve out sufficiently representative pixels and will not increase extra computational complexity.
    Type: Application
    Filed: April 9, 2002
    Publication date: July 3, 2003
    Inventors: Chung-Neng Wang, Shin-Wei Yang, Chi-Min Liu, Tihao Chiang
  • Patent number: 6560371
    Abstract: An apparatus and a concomitant method for using M-ary pyramid decomposition in combination with N-scale tiling to reduce the computational complexity in determining motion vectors for block-based motion estimation is disclosed.
    Type: Grant
    Filed: June 29, 1998
    Date of Patent: May 6, 2003
    Assignee: Sarnoff Corporation
    Inventors: Xudong Song, Tihao Chiang, Ya-Qin Zhang, Ravi Krishnamurthy
  • Patent number: 6553072
    Abstract: A dynamically configurable video signal processing system including an encoder and decoder processes data in the form of hierarchical layers. The system partitions data between hierarchical layers and allows variation in the number of layers employed. Data is automatically partitioned into one or more hierarchical layers as a function of one or more parameters selected from available system bandwidth, input data rate, and output signal quality. In addition, the image resolution and corresponding number of pixels per image of the data may be varied as a function of system parameters.
    Type: Grant
    Filed: July 9, 1997
    Date of Patent: April 22, 2003
    Assignee: Thomson Licensing S.A.
    Inventors: Tihao Chiang, Huifang Sun, Joel Walter Zdepski
  • Patent number: 6434196
    Abstract: A method and apparatus for encoding, illustratively, a video information stream to produce an encoded information stream according to a group of frames (GOF) information structure where the GOF structure and, optionally, a bit budget are modified in response to, respectively, information discontinuities and the presence of redundant information in the video information stream (due to, e.g., 3:2 pull-down processing).
    Type: Grant
    Filed: April 2, 1999
    Date of Patent: August 13, 2002
    Assignee: Sarnoff Corporation
    Inventors: Sriram Sethuraman, Tihao Chiang, Xudong Song, Ravi Krishnamurthy, Paul Hatrack, Ya-Qin Zhang
  • Patent number: 6408101
    Abstract: An apparatus and a concomitant method for using M-ary pyramid decomposition to reduce the computational complexity in determining motion vectors for block-based motion estimation is disclosed.
    Type: Grant
    Filed: December 31, 1997
    Date of Patent: June 18, 2002
    Assignee: Sarnoff Corporation
    Inventors: Ravi Krishnamurthy, Tihao Chiang, Ya-Qin Zhang, Zudong Song
  • Publication number: 20020064228
    Abstract: A method and apparatus for encoding, illustratively, a video information stream to produce an encoded information stream according to a group of frames (GOF) information structure where the GOF structure and, optionally, a bit budget are modified in response to, respectively, information discontinuities and the presence of redundant information in the video information stream (due to, e.g., 3:2 pull-down processing).
    Type: Application
    Filed: April 2, 1999
    Publication date: May 30, 2002
    Inventors: SRIRAM SETHURAMAN, TIHAO CHIANG, XUDONG SONG, RAVI KRISHNAMURTHY, PAUL HATRACK, YA-QIN ZHANG
  • Patent number: 6351491
    Abstract: A method and apparatus for recursively optimizing the rate control of a hierarchical subband coding system that offers spatial, quality and/or complexity scalabilities. The rate control method recursively adjusts the quantizer scale for each layer of a subband tree, i.e., a subband decomposed image.
    Type: Grant
    Filed: June 15, 2000
    Date of Patent: February 26, 2002
    Assignee: Sarnoff Corporation
    Inventors: Hung-Ju Lee, Tihao Chiang, Iraj Sodagar, Ya-Qin Zhang
  • Patent number: 6243497
    Abstract: A method and apparatus for selecting a quantizer scale for each frame to optimize the coding rate is disclosed. A quantizer scale is selected for each frame such that the target bit rate for the frame is achieved while maintaining a uniform visual quality over an entire sequence of frames.
    Type: Grant
    Filed: February 11, 1998
    Date of Patent: June 5, 2001
    Assignee: Sarnoff Corporation
    Inventors: Tihao Chiang, Ya-Qin Zhang
  • Patent number: 6208692
    Abstract: An apparatus and a concomitant method for performing hierarchial block-based motion estimation with a high degree of scalability is disclosed. The present invention decomposes each of the image frames within an image sequence into an M-ary pyramid. Different dynamic ranges for representing the pixel values are used for different levels of the M-ary pyramid, thereby generating a plurality of different “P-bit” levels, i.e., a plurality of different M-ary pyramid architectures. The present scalable hierarchical motion estimation provides the flexibility of switching from one M-ary pyramid architecture to another M-ary pyramid architecture according to the available platform resources and/or user's choice.
    Type: Grant
    Filed: June 29, 1998
    Date of Patent: March 27, 2001
    Assignee: Sarnoff Corporation
    Inventors: Xudong Song, Tihao Chiang, Ya-Qin Zhang, Ravi Krishnamurthy
  • Patent number: 6192081
    Abstract: An apparatus and concomitant method for selecting a macroblock coding mode based upon the quantization scale selected for the macroblock. The total number of bits needed to code each macroblock consists of two parts, bits needed for coding motion vectors and bits for coding the predictive residual. The number of bits for coding the motion vectors is generally obtained from a look-up table. The number of bits for coding the predictive residual is obtained by an estimation which assumes that the number of bits for encoding the predictive residuals is directly proportional to the value of its variance and inversely proportional to the value of quantizer steps (quantizer scale). Using this estimation, the total number of bits necessary to code a macroblock is calculated and compared for each coding mode. By selecting the coding mode with the least number of bits, a near-optimal solution of low complexity for practical implementation is acquired.
    Type: Grant
    Filed: October 26, 1995
    Date of Patent: February 20, 2001
    Assignee: Sarnoff Corporation
    Inventors: Tihao Chiang, Max Chien, Wilson Kwok, Huifang Sun
  • Patent number: 6160846
    Abstract: A method and apparatus for selecting a quantizer scale for each macroblock to maintain the overall quality of the video image while optimizing the coding rate. A quantizer scale is selected for each macroblock such that target bit rate for the picture is achieved while an optimal quantization scale ratio is maintained for successive macroblocks to produce a uniform visual quality over the entire picture. One embodiment applies the method to the frame level while another embodiment applies the method in conjunction with a wavelet transform.
    Type: Grant
    Filed: October 23, 1996
    Date of Patent: December 12, 2000
    Assignees: Sarnoff Corporation, Sharp Corporation
    Inventors: Tihao Chiang, Huifang Sun, Wilson Kwok, Max Chien, Ya-Qin Zhang
  • Patent number: 6148027
    Abstract: An apparatus and a concomitant method for encoding image sequences and, more particularly, to a method for reducing the computational complexity in determining motion vectors for block-based motion estimation and for enhancing the accuracy of motion estimates through the use of non-linear pyramids.
    Type: Grant
    Filed: May 29, 1998
    Date of Patent: November 14, 2000
    Assignee: Sarnoff Corporation
    Inventors: Xudong Song, Ya-Qin Zhang, Tihao Chiang
  • Patent number: 6144701
    Abstract: An apparatus and method that applies an affine transformation to achieve steroscopic coding of video.
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: November 7, 2000
    Assignee: Sarnoff Corporation
    Inventors: Tihao Chiang, Ya-Qin Zhang
  • Patent number: 6084908
    Abstract: A method and apparatus for determining an optimal quadtree structure for quadtree-based variable block size (VBS) motion estimation. The method computes the motion vectors for the entire quadtree from the largest block-size to the smallest block-size. Next, the method may optionally select an optimal quantizer scale for each block. The method then compares from "bottom-up" the sum of the distortion from encoding all sub-blocks or sub-nodes (children) as compared to the distortion from encoding the block or node (parent) from which the subnodes are partitioned from. If the sum of the distortion from encoding the children is greater than that of the parent then the node is "merged". Conversely, if the sum of the distortion from encoding the children is less than that of the parent then the node is "split" and the Lagrangian cost for the parent node is set as the sum of the Lagrangian cost of its children.
    Type: Grant
    Filed: October 23, 1996
    Date of Patent: July 4, 2000
    Assignees: Sarnoff Corporation, Sharp Corporation
    Inventors: Tihao Chiang, Jungwoo Lee, Ya-Qin Zhang, Zixiang Xiong
  • Patent number: 6023296
    Abstract: A method and apparatus for selecting a quantizer scale for each object within a frame to optimize the coding rate is disclosed. A quantizer scale is selected for each region or "object" within each frame such that the target bit rate for the frame is achieved while maintaining a uniform visual quality over the entire frame.
    Type: Grant
    Filed: June 15, 1998
    Date of Patent: February 8, 2000
    Assignee: Sarnoff Corporation
    Inventors: Hung-Ju Lee, Tihao Chiang
  • Patent number: 5828788
    Abstract: A dynamically configurable video signal processing system partitions and encodes data using a variable number of data segments and variable data resolution. The system partitions data into a variable number of data segments by predicting, as a function of the data rate, first and second distortion factors for the data partitioned into first and second numbers of data segments. The first and second distortion factors are mutually compared and the data is partitioned into the number of data segments which exhibits the lower distortion factor value. First and second distortion factors for the data encoded with first and second data resolutions are also predicted. The first and second distortion factors are similarly compared and the data is encoded with the resolution exhibiting the lower distortion factor value.
    Type: Grant
    Filed: December 14, 1995
    Date of Patent: October 27, 1998
    Assignee: Thomson multimedia, S.A.
    Inventors: Tihao Chiang, Huifang Sun, Joel Walter Zdepski