Patents by Inventor Huifang Sun

Huifang Sun 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: 7003154
    Abstract: A system and method for temporally processing an input video including input frames. Each frame has an associated frame play time, and the input video has a total input video play time that is a sum of the input frame play times of all of the input frames. Each of the input frames is classified according to a content characteristic of each frames. An output frame play time is allocated to each of the input frames that is based on the classified content characteristic of each of the input frames to generate a plurality of output frames that form an output video.
    Type: Grant
    Filed: November 17, 2000
    Date of Patent: February 21, 2006
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Kadir A. Peker, Ajay Divakaran, Huifang Sun
  • Publication number: 20050276493
    Abstract: A method selects an optimal coding mode for each macroblock in a video. Each macroblock can be coded according a number of candidate coding modes. A difference between an input macroblock and a predicted macroblock is determined in a transform-domain. The difference is quantized to yield a quantized difference. An inverse quantization is performed on the quantized difference to yield a reconstructed difference. A rate required to code the quantized difference is determined. A distortion is determined according to the difference and the reconstructed difference. Then, a cost is determined for each candidate mode based on the rate and the distortion, and the candidate coding mode that yields a minimum cost is selected as the optimal coding mode for the macroblock.
    Type: Application
    Filed: June 1, 2004
    Publication date: December 15, 2005
    Inventors: Jun Xin, Anthony Vetro, Huifang Sun
  • Publication number: 20050265445
    Abstract: A method and system transcodes an input video based on a first transformation kernel to an output video based on a second transformation kernel. The first and second transformation kernels are different, and the transcoding is performed entirely in a transform-domain. Coefficients of a single transform kernel matrix are determined. Then, input coefficients of the input video are converted to output coefficients of the output video using only the single transform kernel matrix. The input video can be based on DCT coefficients, and the output video can be based on HT coefficients. Alternatively, the input video can be based on HT coefficients, and the output video can be based on DCT coefficients. In addition, the ouput video can have a reduced a spatial resolution from the input video.
    Type: Application
    Filed: June 1, 2004
    Publication date: December 1, 2005
    Inventors: Jun Xin, Anthony Vetro, Huifang Sun
  • Publication number: 20050196052
    Abstract: A method and system processes a compressed input video. The compressed input video is processed to produce an interlaced picture, and macroblock coding information of the input video. The interlaced picture has a first spatial resolution, and a top-field and a bottom-field. The top-field and the bottom-field of the interlaced picture are filtered adaptively according to the macroblock coding information to produce a progressive picture with a second spatial resolution less than the first spatial resolution.
    Type: Application
    Filed: March 2, 2004
    Publication date: September 8, 2005
    Inventors: Jun Xin, Anthony Vetro, Huifang Sun
  • Publication number: 20050175109
    Abstract: A method transcodes an input video to an output video, which can have a lower bit rate than the input video. Sets of rate values and corresponding sets of distortion values are determined for each components of the output video. There is one set of rate values and one corresponding set of distortion values for each component in the output video. The components include a requantization of the input video, inserted resynchronization markers, and inserted intra-blocks. Then, bits are allocated to each of the components in the output video according to the associated set of rate values and the associated corresponding set of distortion values.
    Type: Application
    Filed: February 11, 2004
    Publication date: August 11, 2005
    Inventors: Anthony Vetro, Minghui Xia, Bede Liu, Huifang Sun
  • Publication number: 20050175090
    Abstract: A model stored in a memory accessible by a video transcoder includes a first rate-distortion function modeling a requantization of an input video. A second-rate distortion function models a resynchronization marker insertion rate for the transcoded video, and a third rate-distortion function models an intra-block insertion rate for the transcoded video.
    Type: Application
    Filed: February 11, 2004
    Publication date: August 11, 2005
    Inventors: Anthony Vetro, Minghui Xia, Bede Liu, Huifang Sun
  • Patent number: 6925120
    Abstract: A method codes an output bitstream of an input video so the decoded output bitstream has a constant perceived quality. A base layer bitstream having a constant bit-rate is generated from the input video, and an input enhancement layer bitstream is generated from a difference between the input video and the base layer bitstream. Rate and distortion characteristics are extracted from the base layer bitstream and the input enhancement layer bitstream, and an output enhancement layer bitstream having a variable bit-rate is generated from the input enhancement layer bitstream according to the rate and distortion characteristics. The base layer bitstream and the output enhancement layer bitstream, in combination, form an output bitstream having a variable bit-rate and a constant distortion.
    Type: Grant
    Filed: September 24, 2001
    Date of Patent: August 2, 2005
    Assignee: Mitsubishi Electric Research Labs, Inc.
    Inventors: Ximin Zhang, Anthony Vetro, Yun-Qing Shi, Huifang Sun
  • Publication number: 20050111743
    Abstract: A method encodes an inter-frame of a compressed video, the inter-frame including multiple macroblocks in a predetermined order. Each macroblock has an associated motion vector. For each current macroblock in the predetermined order, a set of near macroblocks are identified. An index is assigned to each near macroblock. A difference between the motion vector of the current macroblock and the motion vector of each near macroblocks is determined. The indices of the near macroblocks are then sorted in order of the differences and appended to the inter-frame.
    Type: Application
    Filed: November 20, 2003
    Publication date: May 26, 2005
    Inventors: Hao-Song Kong, Wei-Ying Kung, Anthony Vetro, Huifang Sun
  • Publication number: 20050111557
    Abstract: A method conceals errors in an intra-fame of compressed video. The intra-frame is decoded to multiple macroblocks. Each macroblock including pixels arranged in a rectangular array. A lost macroblock is identified during the decoding. Pixels along an outer boundary of the lost macroblock are concealed from nearest candidate pixels along outer boundaries of macroblocks immediately adjacent to the lost macroblock. All other pixels in the lost macroblock are concealed from nearest candidate pixels selected from previously concealed pixels in the lost macroblock.
    Type: Application
    Filed: November 20, 2003
    Publication date: May 26, 2005
    Inventors: Hao-Song Kong, Wei-Ying Kung, Anthony Vetro, Huifang Sun
  • Publication number: 20050100236
    Abstract: A method classifies pixels in an image by first partitioning the image into blocks. A variance of an intensity is determined for each pixel, and for each block the pixel with the maximum variance is identified. Then, the blocks are classified into classes according to the maximum variance.
    Type: Application
    Filed: October 14, 2004
    Publication date: May 12, 2005
    Inventors: Hao-Song Kong, Yao Nie, Anthony Vetro, Huifang Sun
  • Publication number: 20050100237
    Abstract: A method filters pixels in an image, by first partitioning the image into blocks. Edge block are identified. A variance of an intensity for each pixel in each edge block is determined. Then, each pixel in each edge block is filtered with a filter that is dependant on the variance of the pixel.
    Type: Application
    Filed: October 14, 2004
    Publication date: May 12, 2005
    Inventors: Hao-Song Kong, Yao Nie, Anthony Vetro, Huifang Sun
  • Publication number: 20050100235
    Abstract: A method classifies pixels in an image. The image can be a decompressed image that was compressed using a block-based compression process. A filter is applied to each pixel in the image to determine a mean intensity value of the pixel. The mean is used to determine a mean-square intensity for each pixel, which in turn is used to determine a variance of the intensity for each pixel. The mean-square represents an average power of a DC component in the image, and the variance represents an average power of AC frequency components in the image. The pixels are then classified according to the variance as being either smooth, edge, or texture pixels. Blocks in the image can then be classified according to the classified pixels, and blocking artifacts and ringing artifacts in the blocks can then be filtered according to the block classification.
    Type: Application
    Filed: November 7, 2003
    Publication date: May 12, 2005
    Inventors: Hao-Song Kong, Anthony Vetro, Huifang Sun
  • Patent number: 6865226
    Abstract: A method analyzes a high-level syntax and structure of a continuous compressed video according to a plurality of states. First, a set of hidden Markov models for each of the states is trained with a training video segmented into known states. Then, a set of domain specific features are extracted from a fixed-length sliding window of the continuous compressed video, and a set of maximum likelihoods is determined for each set of domain specific features using the sets of trained hidden Markov models. Finally, dynamic programming is applied to each set of maximum likelihoods to determine a specific state for each fixed-length sliding window of frames of the compressed video.
    Type: Grant
    Filed: December 5, 2001
    Date of Patent: March 8, 2005
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Lexing Xie, Shih-Fu Chang, Ajay Divakaran, Huifang Sun
  • Patent number: 6859495
    Abstract: A digital video format converter and method therefor includes a first and second converter. The first converter receives a digital video signal and converts, in the frequency domain, inter-coded pictures in the digital video signal into intra-coded pictures. The first converter performs motion compensation in the frequency domain on the inter-coded pictures in the digital video signal to convert the inter-coded pictures into intra-coded pictures. The second converter down converts output of the first converter. Further signal processing then completes placing the digital video signal output by the second converter in a format acceptable to standard lower definition digital decoders.
    Type: Grant
    Filed: October 31, 1996
    Date of Patent: February 22, 2005
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Tommy C. Poon, Huifang Sun, Jay Bao, Anthony Vetro
  • Publication number: 20050036547
    Abstract: A method acquires compressed videos. Intra-, or inter-frames of each compressed video are acquired at a fixed sampling rate. Joint analysis is applied concurrently and in parallel to the compressed videos to determine a variable and non-uniform temporal sampling rate for each compressed video so that a combined distortion is minimized and a combined frame rate constraint is satisfied. Each compressed video is then sampled at the associated variable and non-uniform temporal sampling rate to produce output compressed videos having variable temporal resolutions.
    Type: Application
    Filed: September 11, 2003
    Publication date: February 17, 2005
    Inventors: Anthony Vetro, Huifang Sun
  • Publication number: 20050036543
    Abstract: A method acquires a plurality of input videos. The frames of each input video are acquired at a fixed sampling rate. Joint analysis is applied concurrently and in parallel to the input videos to determine a variable and non-uniform temporal sampling rate for each input video so that a combined distortion is minimized and a combined frame rate constraint is satisfied. Each input video is then sampled at the associated variable and non-uniform temporal sampling rate to produce output videos having variable temporal resolutions.
    Type: Application
    Filed: August 13, 2003
    Publication date: February 17, 2005
    Inventors: Anthony Vetro, Huifang Sun
  • Publication number: 20050013249
    Abstract: A method transmits a video over a network as a bit stream of packets. Real-time feedback information on conditions of the network is received while transmitting the packets. A probability of packet loss is based on the real-time feedback. Then, redundant packets are generated for selected packets of the bit stream if the probability of packet loss is greater than a predetermined threshold.
    Type: Application
    Filed: July 14, 2003
    Publication date: January 20, 2005
    Inventors: Hao-Song Kong, Huai-Rong Shao, Anthony Vetro, Huifang Sun
  • Publication number: 20040264571
    Abstract: A method encodes a video by first measuring a variance of pixel intensities in a current frame. A number of bits to encode the current frame is assigned according to rate and buffer fullness constraints. A multiplier value is determined directly as a function of only the variance and the number of bits assigned to the current frame. Motion vectors between a reference frame and the current frame are estimated, and a sum of absolute difference (SAD) is based on a motion compensated residual between the reference frame and the current frame. An encoding mode is determined for each macro block in the current frame based on the sum of absolute difference, the motion vectors and the multiplier value. Then, the motion compensated residual is encoded based on the encoding mode, multiplier value and the number of allocated bits.
    Type: Application
    Filed: June 24, 2003
    Publication date: December 30, 2004
    Inventors: Ximin Zhang, Hao-Song Kong, Anthony Vetro, Huifang Sun
  • Publication number: 20040233987
    Abstract: A method segments a video into objects, without user assistance. An MPEG compressed video is converted to a structure called a pseudo spatial/temporal data using DCT coefficients and motion vectors. The compressed video is first parsed and the pseudo spatial/temporal data are formed. Seeds macro-blocks are identified using, e.g., the DCT coefficients and changes in the motion vector of macro-blocks.
    Type: Application
    Filed: May 21, 2003
    Publication date: November 25, 2004
    Inventors: Fatih M. Porikli, Huifang Sun, Ajay Divakaran
  • Publication number: 20040202250
    Abstract: A method and system transcodes an input video to a lower spatial resolution. The input video is first decoded into pictures. Each picture includes a set of macroblocks. Each picture sub-sampled to a downscaled picture having a lower spatial resolution. A quantization scale is selected for each macroblock in the downscaled picture. A set of motion vectors is generated for each macroblock in the downscaled picture. A multiplier value based on the quantization scale is determined for each macroblock in the downscaled picture. One of a plurality of encoding modes is selected for each macroblock in the downscaled picture according to the quantization scale, the motion vectors, and the multiplier value. Then, each macroblock in each downscaled picture is encoded according to the quantization scale, the selected encoding mode, and the set of motion vectors to produce an output video having a lower spatial resolution that the input video.
    Type: Application
    Filed: April 14, 2003
    Publication date: October 14, 2004
    Inventors: Hao-Song Kong, Anthony Vetro, Huifang Sun