Patents by Inventor John D. Villasenor
John D. Villasenor 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).
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Patent number: 8549630Abstract: A method of securing bus architecture from a Trojan attack. A restricted address access detector generates an unauthorized access detection signal when a master ID signal is within a restricted range. The unauthorized access detection signal disables the requested slave select signal, and the address decoder instead outputs a default slave select signal. A counter determines the duration of a lock signal from a master, and a comparator activates a malicious bus lock signal if the lock signal duration exceeds a threshold. The master mask register forcibly gates the lock signal upon receipt of the malicious bus lock signal. If the duration of a wait request from a slave exceeds a maximum duration register value, a comparator activates a malicious wait detection signal to disable the wait request signal. The method might include storing identifying information about the malicious master and storing a slave ID corresponding to the malicious slave.Type: GrantFiled: March 7, 2011Date of Patent: October 1, 2013Assignee: The Regents of the University of CaliforniaInventors: John D Villasenor, Lok Won Kim
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Publication number: 20110225651Abstract: A method of securing bus architecture from a Trojan attack. A restricted address access detector generates an unauthorized access detection, signal when a master ID signal is within a restricted range. The unauthorized access detection signal disables the requested slave select signal, and the address decoder instead outputs a default slave select signal. A counter determines the duration of a lock signal from a master, and a comparator activates a malicious bus lock signal if the lock signal duration exceeds a threshold. The master mask register forcibly gates the lock signal upon receipt of the malicious bus lock signal. If the duration of a wait request from a slave exceeds a maximum duration register value, a comparator activates a malicious wait detection signal to disable the wait request signal. The method might include storing identifying information about the malicious master and storing a slave ID corresponding to the malicious slave.Type: ApplicationFiled: March 7, 2011Publication date: September 15, 2011Inventors: John D. Villasenor, Lok Won Kim
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Patent number: 7532669Abstract: A video coding-decoding (CODEC) method in an error resilient mode, a computer readable medium having a computer program for the video CODEC method, and a video CODEC apparatus. The video CODEC method provides more resilience against channel error such that communications are less affected by error under conditions in which errors are a serious problem such as in a wireless communications channel. In the video CODEC method, a header data part (HDP) bit region, a motion vector data part (MVDP) bit region and a discrete cosine transform data part (DDP) bit regions are partitioned from each macro block of the video data in an error resilient mode, and then the partitioned bit regions are variable-length-coded. Then, the bit regions selected from the variable-length coded bit regions according to a predetermined priority for recovery are reversible-variable-length-coded, and markers are then inserted into the variable-length coded or reversible-variable-length-coded bit regions.Type: GrantFiled: February 28, 2003Date of Patent: May 12, 2009Assignees: Samsung Electronics Co., Ltd., University of CaliforniaInventors: Jiangtao Wen, John D. Villasenor, Jeong-hoon Park
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Patent number: 7340671Abstract: The present invention includes a technique for updating messages that originate at the constraint nodes of bi-partite graphs in Low Density Parity Check codes. The technique computes only two outgoing magnitudes at each constraint node and exhibits no measurable performance loss as compared to exact belief propagation which computes a unique magnitude for each departing edge from a given constraint node. The technique eliminates the need for memory based table look-up in the constraint node processing and has been implemented, in one embodiment, using only shift, add, and comparison operations.Type: GrantFiled: October 8, 2004Date of Patent: March 4, 2008Assignee: Regents of the University of CaliforniaInventors: Christopher R. Jones, John D. Villasenor
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Patent number: 7177355Abstract: A method of representing encoding or non-encoding by extending a video information field of a block when coding video information, is provided. The method of representing encoding or non-encoding by extending an information field for representing encoding or non-encoding is applied to an error allowable mode. Also, the amount of bits depending on the characteristics of video information to be encoded can be reduced. In this method, an image is encoded by extending a code (COD) field which is used in H.263 and MPEG-4 to indicate the cases where neither a motion vector (MV) nor a discrete cosine transform (DCT) value are encoded, where both the MV and the DCT value are encoded, and where only the MV is encoded. Therefore, in a channel with errors, the extended OCD field can be used in the error allowable mode. Also, video information can be encoded using a smaller amount of bits where the motion of an image is constant, than in the conventional art.Type: GrantFiled: December 1, 1998Date of Patent: February 13, 2007Assignees: Samsung Electronics Co., Ltd., The Regents of the University of CaliforniaInventors: Jiangtao Wen, John D. Villasenor, Jeong-hoon Park
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Patent number: 6768775Abstract: A video coding-decoding (CODEC) method in an error resilient mode, a computer readable medium having a computer program for the video CODEC method, and a video CODEC apparatus. The video CODEC method provides more resilience against channel error such that communications are less affected by error under conditions in which errors are a serious problem such as in a wireless communications channel. In the video CODEC method, a header data part (HDP) bit region, a motion vector data part (MVDP) bit region and a discrete cosine transform data part (DDP) bit regions are partitioned from each macro block of the video data in an error resilient mode, and then the partitioned bit regions are variable-length-coded. Then, the bit regions selected from the variable-length coded bit regions according to a predetermined priority for recovery are reversible-variable-length-coded, and markers are then inserted into the variable-length coded or reversible-variable-length-coded bit regions.Type: GrantFiled: December 1, 1998Date of Patent: July 27, 2004Assignees: Samsung Electronics Co., Ltd., The Regents of the University of CaliforniaInventors: Jiangtao Wen, John D. Villasenor, Jeong-hoon Park
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Publication number: 20030128755Abstract: A video coding-decoding (CODEC) method in an error resilient mode, a computer readable medium having a computer program for the video CODEC method, and a video CODEC apparatus. The video CODEC method provides more resilience against channel error such that communications are less affected by error under conditions in which errors are a serious problem such as in a wireless communications channel. In the video CODEC method, a header data part (HDP) bit region, a motion vector data part (MVDP) bit region and a discrete cosine transform data part (DDP) bit regions are partitioned from each macro block of the video data in an error resilient mode, and then the partitioned bit regions are variable-length-coded. Then, the bit regions selected from the variable-length coded bit regions according to a predetermined priority for recovery are reversible-variable-length-coded, and markers are then inserted into the variable-length coded or reversible-variable-length-coded bit regions.Type: ApplicationFiled: February 28, 2003Publication date: July 10, 2003Applicant: SAMSUNG ELECTRONICS CO., LTD., UNIVERSITY OF CALIFORNIAInventors: Jiangtao Wen, John D. Villasenor, Jeong-Hoon Park
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Patent number: 6426976Abstract: A motion vector prediction method in an error resilient mode. In the motion vector prediction method capable of decoding backwards, motion vectors of macro blocks are calculated, and motion vectors of macro blocks each having one motion vector are predicted while moving to another macro block from left to right, and motion vectors of macro blocks each having four motion vectors are continuously predicted in a predetermined sequence to have correlation in prediction of the four motion vectors. Thus, in the motion vector prediction method based on the image signal compression method of the MPEG-4 or H.263 standard, the motion vector prediction is performed with continuity and correlation among the motion vectors, so that two-way decoding is possible during transmission of blocks with a predetermined packet, resulting in better error resilient characteristics.Type: GrantFiled: December 1, 1998Date of Patent: July 30, 2002Assignees: Samsung Electronics Co., Ltd., Regents of the University of CaliforniaInventors: Jiangtao Wen, John D. Villasenor, Jeong-hoon Park, Dong-seek Park
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Patent number: 5818877Abstract: A method generates a reduced number of values representing a sequence of grouped data values and partitions the reduced number of values by first mapping data values into groups of symbols and then partitioning the resulting stream of symbols. The digits representing the first data value in each group are replaced with symbols from a first alphabet. The most significant digit of the second data value in each group and the sign of that second data value are also represented by a symbol from the first symbol set, while the remaining significant bits of the second data value in each group are represented by symbols from a second symbol set. A stream of symbols which represent a sequence of grouped data values is partitioned into first partition symbol groups and second partition symbol groups. Each first partition symbol group comprises the symbols representing the first data value in each group and also the symbol representing the least significant bit of the second data value which follows.Type: GrantFiled: March 26, 1996Date of Patent: October 6, 1998Assignee: The Regents of the University of CaliforniaInventors: Min-Jen Tsai, John D. Villasenor, Feng Chen
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Patent number: RE40372Abstract: A motion vector prediction method in an error resilient mode. In the motion vector prediction method capable of decoding backwards, motion vectors of macro blocks are calculated, and motion vectors of macro blocks each having one motion vector are predicted while moving to another macro block from left to right, and motion vectors of macro blocks each having four motion vectors are continuously predicted in a predetermined sequence to have correlation in prediction of the four motion vectors. Thus, in the motion vector prediction method based on the image signal compression method of the MPEG-4 or H.263 standard, the motion vector prediction is performed with continuity and correlation among the motion vectors, so that two-way decoding is possible during transmission of blocks with a predetermined packet, resulting in better error resilient characteristics.Type: GrantFiled: June 8, 2004Date of Patent: June 10, 2008Assignees: Samsung Electronics Co., Ltd., University of CaliforniaInventors: Jiangtao Wen, John D. Villasenor, Jeong-hoon Park, Dong-seek Park