Patents by Inventor Chang Wen Chen

Chang Wen Chen 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: 7953224
    Abstract: A method and system for encrypting a video compressed with MPEG-4 FGS compression with minimal overhead is provided. The encryption system encrypts the video into independently encrypted segments that can be either a video packet or a video block. When the encryption system encrypts based on video packets, it encrypts the data to ensure that the encrypted data does not emulate any video packet delimiting markers. When the encryption system encrypts based on video blocks, it encrypts the coded bitstream for each video block independently, from the most significant bitplane to the least significant bitplane, using either a stream or a block cipher. After all the video blocks are independently encrypted, the encryption system partitions the encrypted data into video packets and adds a buffering bit, if necessary, to prevent emulation of video packet delimiting markers. The encryption system may generate an initialization vector for each independently encrypted segment.
    Type: Grant
    Filed: May 19, 2006
    Date of Patent: May 31, 2011
    Assignee: Microsoft Corporation
    Inventors: Bin Zhu, Chang Wen Chen, Shipeng Li, Yang Yang
  • Publication number: 20090279462
    Abstract: Described is a technology by which a roadside-to-vehicle communication system may be implemented, including via a stateful scheduling with network coding scheme that enhances network capacity. Moving vehicles request and receive data from a roadside access points. Each of the access points operate a stateful scheduling algorithm that serves multiple vehicles by integrating network coding within a timeslot. In one aspect, the state of each vehicle's previously received and retained data is obtained, and used to enhance network capacity by combining as many packets as possible for multiple recipients in network coding.
    Type: Application
    Filed: May 9, 2008
    Publication date: November 12, 2009
    Applicant: MICROSOFT CORPORATION
    Inventors: Chong Luo, Han Cheng Lu, Wei Pu, Feng Wu, Chang Wen Chen
  • Publication number: 20090252146
    Abstract: Described is continuous network coding, in which a relay sends probability data comprising a continuous number for use as parity data. The node receives streams of bits sent from sources towards a destination, and computes the probability data based on current noise data and/or fading data. A selected set of the bits (all or some subset thereof) are combined, e.g., XOR-ed or concatenated, and send to the destination. Phase modulation is performed to convey probability information based on the probability data. The destination demodulates the signal to obtain the probability information, and combines the probability information with the data directly received from sources to perform joint decoding. The number of bits in the set of selected bits may be adaptively chosen based on current channel conditions, e.g., increased when the channel conditions from the sources directly to a destination are poor relative to the channel conditions via the relay.
    Type: Application
    Filed: April 3, 2008
    Publication date: October 8, 2009
    Applicant: Microsoft Corporation
    Inventors: Chong Luo, Wei Pu, Feng Wu, Shipeng Li, Chang Wen Chen
  • Patent number: 7023447
    Abstract: A novel multi-resolution block sampling based texture analysis/synthesis algorithm. A reference texture is assumed to be sample from a probability function. The synthesis of a similar, but distinctive, synthetic texture is handled in a process and by an apparatus that first estimates and then resamples the probability function. In order to achieve good and fast estimation of the probability function for a reference texture and in order to retain the texel structural information during the synthesis, a novel concept of block sampling and a corresponding novel texture synthesis scheme based on multi-resolution block sampling is employed. As a result of this novel approach, the computational complexity of the present invention is much lower than that of other approaches to the problem. In addition, for textures that exhibit a high degree of directionality, a process, which integrates estimation of dominant texture direction and the synthesis algorithm is employed to handle directional textures.
    Type: Grant
    Filed: May 2, 2001
    Date of Patent: April 4, 2006
    Assignee: Eastman Kodak Company
    Inventors: Jiebo Luo, Yue Yu, Chang Wen Chen
  • Publication number: 20020171660
    Abstract: A novel multi-resolution block sampling based texture analysis/synthesis algorithm. A reference texture is assumed to be sample from a probability function. The synthesis of a similar, but distinctive, synthetic texture is handled in a process and by an apparatus that first estimates and then resamples the probability function. In order to achieve good and fast estimation of the probability function for a reference texture and in order to retain the texel structural information during the synthesis, a novel concept of block sampling and a corresponding novel texture synthesis scheme based on multi-resolution block sampling is employed. As a result of this novel approach, the computational complexity of the present invention is much lower than that of other approaches to the problem. In addition, for textures that exhibit a high degree of directionality, a process, which integrates estimation of dominant texture direction and the synthesis algorithm is employed to handle directional textures.
    Type: Application
    Filed: May 2, 2001
    Publication date: November 21, 2002
    Applicant: Eastman Kodak Company
    Inventors: Jiebo Luo, Yue Yu, Chang Wen Chen
  • Patent number: 5998717
    Abstract: A kettledrum is connected to a support leg stand by a connecting mechanism which includes a connecting member attached to the leg stand and a drum clamping mechanism attached to the counterhoop of the drum. The drum clamping mechanism includes an auxiliary clamping unit having a joining part which engages a joining hole formed in a main clamping unit. Three connecting mechanisms may be equiangularly spaced around the drum for providing a stable support of the drum and reduction of vibrations.
    Type: Grant
    Filed: July 13, 1998
    Date of Patent: December 7, 1999
    Inventor: Chang-Wen Chen
  • Patent number: 5628088
    Abstract: A multistage adjustable device for trunk bracket has a fixed handle, a driving handle, two inner sleeves, two drawbars, two brakes, two seats, two checking bodies, two outer sleeves and two positioning plates. The fixed handle has two ends. Two sockets are disposed in the corresponding ends of the fixed handle. The front end of the inner sleeve is inserted in the socket. A slot is formed on the socket and a corresponding slot is formed on the inner sleeve. Two recess holes are formed in the two end portions of the fixed handle. Each end of the driving handle has a fin which has a hole to be hooked by a hook at the upper end of the drawbar. Two posts protrude upwardly on the two end portions of the driving handle. The posts are inserted in the recess holes. A hollow inner sleeve connects the socket. The lower end of the drawbar is inserted in the brake which has a stop portion and a shaft sleeve. The checking body has a cap and a positioning rod.
    Type: Grant
    Filed: July 24, 1995
    Date of Patent: May 13, 1997
    Inventor: Chang-Wen Chen
  • Patent number: 5627882
    Abstract: An enhanced power saving method for operating a battery powered hand-held communication system, particularly a cordless phone system, and the communication system constructed in accordance with the power saving method are described. The power saving method consists of an algorithm which divides the standby time of the communication system into a scanning mode and a sleep mode having several different levels to allow the system to enter the scanning mode intermittently. Each level of the sleep mode corresponds to a given length of delay time between two successive scanning periods. The communication system enters different levels of the sleep mode in accordance with the standby time history. The more standby time that passes, the longer the sleep time for the level that the system may enter. This reduces the scan rate when the system is not used for a long period.
    Type: Grant
    Filed: May 26, 1994
    Date of Patent: May 6, 1997
    Assignee: U.S. Philips Corporation
    Inventors: Cheng-Tung Chien, Chang-Wen Chen, Chiu-Hong But