Patents by Inventor Albert S. Wang

Albert S. Wang 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: 7565017
    Abstract: An adaptive entropy coder is coupled with a localized conditioning context to provide efficient compression of images with localized high frequency variations. In one implementation, an arithmetic coder can be used as the adaptive entropy coder. The localized conditioning context includes a basic context region with multiple context pixels that are adjacent the current pixel, each of the context pixels having an image tone. A state is determined for the basic context region based upon a pattern of unique image tones among the context pixels therein. An extended context region that includes the basic context region is used to identify a non-local trend within the context pixels and a corresponding state. A current pixel may be arithmetically encoded according to a previously encoded pixel having the same tone or as a not-in-context element. In one implementation, a not-in-context element may be represented by a tone in a color cache that is arranged as an ordered list of most recent not-in-context values.
    Type: Grant
    Filed: July 1, 2005
    Date of Patent: July 21, 2009
    Assignee: Microsoft Corporation
    Inventor: Albert S. Wang
  • Patent number: 7391912
    Abstract: An adaptive entropy coder is coupled with a localized conditioning context to provide efficient compression of images with localized high frequency variations. In one implementation, an arithmetic coder can be used as the adaptive entropy coder. The localized conditioning context includes a basic context region with multiple context pixels that are adjacent the current pixel, each of the context pixels having an image tone. A state is determined for the basic context region based upon a pattern of unique image tones among the context pixels therein. An extended context region that includes the basic context region is used to identify a non-local trend within the context pixels and a corresponding state. A current pixel may be arithmetically encoded according to a previously encoded pixel having the same tone or as a not-in-context element. In one implementation, a not-in-context element may be represented by a tone in a color cache that is arranged as an ordered list of most recent not-in-context values.
    Type: Grant
    Filed: July 1, 2005
    Date of Patent: June 24, 2008
    Assignee: Microsoft Corporation
    Inventor: Albert S. Wang
  • Patent number: 7181072
    Abstract: An apparatus and method for encoding video frames is provided. The video frames are divided into blocks for encoding. Encoding of the video blocks utilizes motion detection, motion estimation and adaptive compression, to obtain the desired compression for a particular bit rate. Adaptive compression includes intra compression (without regard to other frames) and inter compression (with regard to other frames). Intra compression, inter compression with motion detection, and inter compression with motion estimation are performed on a block by block basis, as needed. Segmentation is provided to compare encoding of a block with encoding of its sub-blocks, and to select the best block size for encoding.
    Type: Grant
    Filed: March 31, 2003
    Date of Patent: February 20, 2007
    Assignee: Microsoft Corporation
    Inventors: Albert S. Wang, Sanjeev Mehrotra
  • Patent number: 7162091
    Abstract: An apparatus and method for encoding video frames is provided. The video frames are divided into blocks for encoding. Encoding of the video blocks utilizes motion detection, motion estimation and adaptive compression, to obtain the desired compression for a particular bit rate. Adaptive compression includes intra compression (without regard to other frames) and inter compression (with regard to other frames). Intra compression, inter compression with motion detection, and inter compression with motion estimation are performed on a block by block basis, as needed. Segmentation is provided to compare encoding of a block with encoding of its sub-blocks, and to select the best block size for encoding.
    Type: Grant
    Filed: March 31, 2003
    Date of Patent: January 9, 2007
    Assignee: Microsoft Corporation
    Inventors: Albert S. Wang, Sanjeev Mehrotra
  • Patent number: 7154951
    Abstract: A motion video signal encoder maximizes image quality without exceeding transmission bandwidth available to carry the encoded motion video signal by comparing encoded frames of the motion video signal to a desired size of frame. If the size of encoded frames differ from the desired size, encoding is adjusted to produce encoded frames closer in size to the desired size. In addition, a cumulative bandwidth error records an accumulated amount of available bandwidth. The cumulative bandwidth error is adjusted as time elapses to add to the available bandwidth and as each frame is encoded to thereby consume bandwidth. As the cumulative bandwidth error grows in magnitude above or below zero, encoding is adjusted as needed to either improve image quality to more completely consume available bandwidth or to reduce image quality to thereby consume less bandwidth and to thereby cause the cumulative bandwidth error to move toward zero.
    Type: Grant
    Filed: March 16, 2004
    Date of Patent: December 26, 2006
    Assignee: Microsoft Corporation
    Inventor: Albert S. Wang
  • Patent number: 7139313
    Abstract: A motion video signal encoder maximizes image quality without exceeding transmission bandwidth available to carry the encoded motion video signal by comparing encoded frames of the motion video signal to a desired size of frame. If the size of encoded frames differ from the desired size, quantization is adjusted to produce encoded frames closer in size to the desired size. In addition, a cumulative bandwidth balance records an accumulated amount of available bandwidth. The cumulative bandwidth balance is adjusted as time elapses to add to the available bandwidth and as each frame is encoded to thereby consume bandwidth. If the cumulative bandwidth balance deviates from a predetermined range, quantization is adjusted as needed to either improve image quality to more completely consume available bandwidth or to reduce image quality to thereby consume less bandwidth.
    Type: Grant
    Filed: June 1, 2005
    Date of Patent: November 21, 2006
    Assignee: Microsoft Corporation
    Inventor: Albert S. Wang
  • Patent number: 7072396
    Abstract: A motion video signal encoder maximizes image quality without exceeding transmission bandwidth available to carry the encoded motion video signal by comparing encoded frames of the motion video signal to a desired size of frame. If the size of encoded frames differ from the desired size, encoding is adjusted to produce encoded frames closer in size to the desired size. In addition, a cumulative bandwidth error records an accumulated amount of available bandwidth. The cumulative bandwidth error is adjusted as time elapses to add to the available bandwidth and as each frame is encoded to thereby consume bandwidth. As the cumulative bandwidth error grows in magnitude above or below zero, encoding is adjusted as needed to either improve image quality to more completely consume available bandwidth or to reduce image quality to thereby consume less bandwidth and to thereby cause the cumulative bandwidth error to move toward zero.
    Type: Grant
    Filed: March 16, 2004
    Date of Patent: July 4, 2006
    Assignee: Microsoft Corporation
    Inventor: Albert S. Wang
  • Patent number: 6996097
    Abstract: A system and method for correcting errors and losses occurring during a receiver-driven layered multicast (RLM) of real-time media over a heterogeneous packet network such as the Internet. This is accomplished by augmenting RLM with one or more layers of error correction information. This allows each receiver to separately optimize the quality of received audio and video information by subscribing to at least one error correction layer. Ideally, each source layer in a RLM would have one or more multicasted error correction data streams (i.e., layers) associated therewith. Each of the error correction layers would contain information that can be used to replace lost packets from the associated source layer. More than one error correction layer is proposed as some of the error correction packets contained in the data stream needed to replace the packets lost in the associated source stream may themselves be lost in transmission.
    Type: Grant
    Filed: May 21, 1999
    Date of Patent: February 7, 2006
    Assignee: Microsoft Corporation
    Inventors: Philip A. Chou, Albert S. Wang, Sanjeev Mehrotra, Alexander E. Mohr
  • Patent number: 6937657
    Abstract: A motion video signal encoder maximizes image quality without exceeding transmission bandwidth available to carry the encoded motion video signal by comparing encoded frames of the motion video signal to a desired size of frame. If the size of encoded frames differ from the desired size, quantization is adjusted to produce encoded frames closer in size to the desired size. In addition, a cumulative bandwidth balance records an accumulated amount of available bandwidth. The cumulative bandwidth balance is adjusted as time elapses to add to the available bandwidth and as each frame is encoded to thereby consume bandwidth. If the cumulative bandwidth balance deviates from a predetermined range, quantization is adjusted as needed to either improve image quality to more completely consume available bandwidth or to reduce image quality to thereby consume less bandwidth.
    Type: Grant
    Filed: March 16, 2004
    Date of Patent: August 30, 2005
    Assignee: Microsoft Corporation
    Inventor: Albert S. Wang
  • Publication number: 20040184535
    Abstract: A motion video signal encoder maximizes image quality without exceeding transmission bandwidth available to carry the encoded motion video signal by comparing encoded frames of the motion video signal to a desired size of frame. If the size of encoded frames differ from the desired size, encoding is adjusted to produce encoded frames closer in size to the desired size. In addition, a cumulative bandwidth error records an accumulated amount of available bandwidth. The cumulative bandwidth error is adjusted as time elapses to add to the available bandwidth and as each frame is encoded to thereby consume bandwidth. As the cumulative bandwidth error grows in magnitude above or below zero, encoding is adjusted as needed to either improve image quality to more completely consume available bandwidth or to reduce image quality to thereby consume less bandwidth and to thereby cause the cumulative bandwidth error to move toward zero.
    Type: Application
    Filed: March 16, 2004
    Publication date: September 23, 2004
    Applicant: Microsoft Corporation
    Inventor: Albert S. Wang
  • Publication number: 20040184533
    Abstract: A motion video signal encoder maximizes image quality without exceeding transmission bandwidth available to carry the encoded motion video signal by comparing encoded frames of the motion video signal to a desired size of frame. If the size of encoded frames differ from the desired size, encoding is adjusted to produce encoded frames closer in size to the desired size. In addition, a cumulative bandwidth error records an accumulated amount of available bandwidth. The cumulative bandwidth error is adjusted as time elapses to add to the available bandwidth and as each frame is encoded to thereby consume bandwidth. As the cumulative bandwidth error grows in magnitude above or below zero, encoding is adjusted as needed to either improve image quality to more completely consume available bandwidth or to reduce image quality to thereby consume less bandwidth and to thereby cause the cumulative bandwidth error to move toward zero.
    Type: Application
    Filed: March 16, 2004
    Publication date: September 23, 2004
    Applicant: Microsoft Corporation
    Inventor: Albert S. Wang
  • Publication number: 20040184534
    Abstract: A motion video signal encoder maximizes image quality without exceeding transmission bandwidth available to carry the encoded motion video signal by comparing encoded frames of the motion video signal to a desired size of frame. If the size of encoded frames differ from the desired size, quantization is adjusted to produce encoded frames closer in size to the desired size. In addition, a cumulative bandwidth balance records an accumulated amount of available bandwidth. The cumulative bandwidth balance is adjusted as time elapses to add to the available bandwidth and as each frame is encoded to thereby consume bandwidth. If the cumulative bandwidth balance deviates from a predetermined range, quantization is adjusted as needed to either improve image quality to more completely consume available bandwidth or to reduce image quality to thereby consume less bandwidth.
    Type: Application
    Filed: March 16, 2004
    Publication date: September 23, 2004
    Applicant: Microsoft Corporation
    Inventor: Albert S. Wang
  • Patent number: 6707852
    Abstract: A motion video signal encoder maximizes image quality without exceeding transmission bandwidth available to carry the encoded motion video signal by comparing encoded frames of the motion video signal to a desired size of frame. If the size of encoded frames differ from the desired size, encoding is adjusted to produce encoded frames closer in size to the desired size. In addition, a cumulative bandwidth error records an accumulated amount of available bandwidth. The cumulative bandwidth error is adjusted as time elapses to add to the available bandwidth and as each frame is encoded to thereby consume bandwidth. As the cumulative bandwidth error grows in magnitude above or below zero, encoding is adjusted as needed to either improve image quality to more completely consume available bandwidth or to reduce image quality to thereby consume less bandwidth and to thereby cause the cumulative bandwidth error to move toward zero.
    Type: Grant
    Filed: August 31, 2000
    Date of Patent: March 16, 2004
    Assignee: Microsoft Corporation
    Inventor: Albert S. Wang
  • Publication number: 20030185452
    Abstract: An apparatus and method for encoding video frames is provided. The video frames are divided into blocks for encoding. Encoding of the video blocks utilizes motion detection, motion estimation and adaptive compression, to obtain the desired compression for a particular bit rate. Adaptive compression includes intra compression (without regard to other frames) and inter compression (with regard to other frames). Intra compression, inter compression with motion detection, and inter compression with motion estimation are performed on a block by block basis, as needed. Segmentation is provided to compare encoding of a block with encoding of its sub-blocks, and to select the best block size for encoding.
    Type: Application
    Filed: March 31, 2003
    Publication date: October 2, 2003
    Inventors: Albert S. Wang, Sanjeev Mehrotra
  • Patent number: 6594798
    Abstract: Correction of errors and losses in a receiver-driven layered multicast (RLM) of real-time media over a network is augmented using one or more layers of error correction information. Each receiver separately optimizes the quality of received information by subscribing to at least one error correction layer. Ideally, each source layer in a RLM has one or more associated multicasted error correction data streams. Each error correction layer contains information for replacing lost packets from the associated source layer. More than one error correction layer is proposed to correct for lost packets in other error correction layers. Error correction streams are preferably generated using a pseudo-Automatic Repeat Request (ARQ) wherein a broadcaster sends both the source packets in a primary stream and delayed versions thereof in one or more redundant streams. A hybrid technique combines the psuedo-ARQ method with an adaptation of Forward Error Correction (FEC) techniques.
    Type: Grant
    Filed: May 21, 1999
    Date of Patent: July 15, 2003
    Assignee: Microsoft Corporation
    Inventors: Philip A. Chou, Albert S. Wang, Sanjeev Mehrotra, Alexander E. Mohr
  • Patent number: 6571016
    Abstract: An apparatus and method for encoding video frames is provided. The video frames are divided into blocks for encoding. Encoding of the video blocks utilizes motion detection, motion estimation and adaptive compression, to obtain the desired compression for a particular bit rate. Adaptive compression includes intra compression (without regard to other frames) and inter compression (with regard to other frames). Intra compression, inter compression with motion detection, and inter compression with motion estimation are performed on a block by block basis, as needed. Segmentation is provided to compare encoding of a block with encoding of its sub-blocks, and to select the best block size for encoding.
    Type: Grant
    Filed: May 5, 1997
    Date of Patent: May 27, 2003
    Assignee: Microsoft Corporation
    Inventors: Sanjeev Mehrotra, Albert S. Wang
  • Patent number: 6532562
    Abstract: “Correction of errors and losses occurring during a receiver-driven layered multicast (RLM) of real-time media over a heterogeneous packet network such as the Internet is accomplished by augmenting RLM with one or more layers of error correction information. Each receiver separately optimizes the quality of received audio and video information by subscribing to at least one error correction layer. Ideally, each source layer in a RLM would have one or more associated multicasted error correction data streams (i.e., layers). Each error correction layer contains information that can be used to replace lost packets from the associated source layer. More than one error correction layer is proposed as some of the error correction packets contained in the data stream needed to replace the packets lost in the associated source stream may themselves be lost in transmission.
    Type: Grant
    Filed: May 21, 1999
    Date of Patent: March 11, 2003
    Inventors: Philip A. Chou, Albert S. Wang, Sanjeev Mehrotra
  • Patent number: 6473461
    Abstract: A motion estimator/compensator determines whether to use half-pixel motion vector encoding by comparing the relative benefit of using half-pixel encoding, represented in terms of distortion between the macroblock as encoded and prior to encoding, to the processing burden imposed upon the client computer system in decoding the half-pixel encoded macroblock. Specifically, the motion estimator/compensator quantifies distortions in encoding a subject macroblock as a motion vector to (i) a whole pixel pseudo-macroblock, (ii) a half-column pixel pseudo-macroblock, (iii) a half-row pixel pseudo-macroblock, or (iv) a half-column/half-row pixel pseudo-macroblock. The type of motion vector encoding having the smallest combination of distortion and decoder processing burden is selected and used to encode the subject macroblock.
    Type: Grant
    Filed: April 4, 2000
    Date of Patent: October 29, 2002
    Assignee: Microsoft Corporation
    Inventor: Albert S. Wang
  • Patent number: 6470469
    Abstract: A projection onto convex sets (POCS)-based method for consistent reconstruction of a signal from a subset of quantized coefficients received from an N×K overcomplete transform. By choosing a frame operator F to be the concatenization of two or more K×K invertible transforms, the POCS projections are calculated in RK space using only the K×K transforms and their inverses, rather than the larger RN space using pseudo inverse transforms. Practical reconstructions are enabled based on, for example, wavelet, subband, or lapped transforms of an entire image. In one embodiment, unequal error protection for multiple description source coding is provided. In particular, given a bit-plane representation of the coefficients in an overcomplete representation of the source, one embodiment of the present invention provides coding the most significant bits with the highest redundancy and the least significant bits with the lowest redundancy.
    Type: Grant
    Filed: March 26, 1999
    Date of Patent: October 22, 2002
    Assignee: Microsoft Corp.
    Inventors: Philip A. Chou, Sanjeev Mehrotra, Albert S. Wang
  • Patent number: 6460153
    Abstract: A projection onto convex sets (POCS)-based method for consistent reconstruction of a signal from a subset of quantized coefficients received from an N×K overcomplete transform. By choosing a frame operator F to be the concatenization of two or more K×K invertible transforms, the POCS projections are calculated in RK space using only the K×K transforms and their inverses, rather than the larger RN space using pseudo inverse transforms. Practical reconstructions are enabled based on, for example, wavelet, subband, or lapped transforms of an entire image. In one embodiment, unequal error protection for multiple description source coding is provided. In particular, given a bit-plane representation of the coefficients in an overcomplete representation of the source, one embodiment of the present invention provides coding the most significant bits with the highest redundancy and the least significant bits with the lowest redundancy.
    Type: Grant
    Filed: March 26, 1999
    Date of Patent: October 1, 2002
    Assignee: Microsoft Corp.
    Inventors: Philip A. Chou, Sanjeev Mehrotra, Albert S. Wang