Patents by Inventor Christos Chrysafis
Christos Chrysafis 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: 8373718Abstract: Embodiments of the claimed subject matter provide a system and process for enhancing the display of color in a graphical display. In one embodiment, a process is provided for color enhancement using a detection volume and a shift volume. In one embodiment, input from pixels, as color data, is compared to a detection volume. If the color data of an input is detected in the detection volume, the color data is modified to a corresponding position in the shift volume, the modification consisting of an enhancement to the original color.Type: GrantFiled: December 10, 2008Date of Patent: February 12, 2013Assignee: NVIDIA CorporationInventors: Santanu Dutta, Christos Chrysafis
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Publication number: 20100141671Abstract: Embodiments of the claimed subject matter provide a system and process for enhancing the display of color in a graphical display. In one embodiment, a process is provided for color enhancement using a detection volume and a shift volume. In one embodiment, input from pixels, as color data, is compared to a detection volume. If the color data of an input is detected in the detection volume, the color data is modified to a corresponding position in the shift volume, the modification consisting of an enhancement to the original color.Type: ApplicationFiled: December 10, 2008Publication date: June 10, 2010Applicant: NVIDIA CORPORATIONInventors: Santanu Dutta, Christos Chrysafis
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Publication number: 20070110151Abstract: A system and method are provided for encoding and compressing video data. A memory device is configured to store video data, and a corresponding memory controller controls the storage of video data in the memory device. A frame buffer compression module compresses frame data received from a video module to be stored in the memory device according to the memory controller and decompresses compressed frame data received from the memory device according to the memory controller for use by a video module. The frame buffer compression module includes a frame buffer compression encoder configured to encode and compress frame data received from a video module for storage in memory according to the memory controller. The frame buffer also includes a corresponding frame buffer compression decoder configured to decode and decompress frame data received from memory according to the memory controller for use by a video module.Type: ApplicationFiled: November 14, 2005Publication date: May 17, 2007Applicant: ESS Technology, Inc.Inventors: Siu-Leong Yu, Nien-Tsu Wang, Kou-Hu Tzou, Christos Chrysafis, Xuhui Wu
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Patent number: 7120196Abstract: To encode an unencoded block of a frame, a search window is defined within the frame. Each pixel disposed within the search window and disposed in the unencoded portion of the frame that is assigned a value. A difference is computed between the unencoded block and each possible block within the search window. The block having the smallest difference, together with this difference are used to encode the unencoded block.Type: GrantFiled: April 25, 2003Date of Patent: October 10, 2006Assignee: ESS Technology, Inc.Inventors: Siu-Leong Yu, Christos Chrysafis
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Patent number: 6956973Abstract: A method of image encoding using subband decomposition followed by modified zerotree coding with a symbols for zero and significant zerotrees and isolated zeroes and isolated significant coefficients.Type: GrantFiled: September 30, 1998Date of Patent: October 18, 2005Assignee: Texas Instruments IncorporatedInventors: Jie Liang, Antonio Ortega, Youngjun Yoo, Christos Chrysafis
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Publication number: 20040230425Abstract: To determine the number of bits to encode a current audio frame, in accordance with a running average of the common scale factors for all preceding audio frames, a common scale factor for the-current frame is computed. The current frame is encoded using the computed common scale factor if the same falls within a defined range, and the number of bits required to so encode the frame also falls within a calculated range. If, the number of bits required to so encode the frame falls outside the calculated range, an energy level associated with the current frame and a running average of the energies of all previous frames is computed, which in turn, are used to compute a target bit rate. Thereafter, a common scale factor which results in coding of the current frame using a number of bits close to the target bit rate is obtained.Type: ApplicationFiled: May 16, 2003Publication date: November 18, 2004Applicant: Divio, Inc.Inventors: Siu-Leong Yu, Christos Chrysafis, Johnny Wang
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Publication number: 20040230423Abstract: To select the encoding mode of an audio signal in a multi-channel system, a level of energy of the audio signal associated with each channel is determined, which in turn is used to compute a first value. Next, a second value based on a degree of correlation of the signals of each channel is determined. If the first value is smaller than the second value, the audio signal is encoded using a first encoding mode. Next, a third value defined by the energy levels and a fourth value defined by the correlation are computed. If the first value is greater than the second value, and the third value is smaller than the fourth value, the audio signal is encoded using a second encoding mode. Otherwise the audio signal is encoded using a third encoding mode.Type: ApplicationFiled: May 16, 2003Publication date: November 18, 2004Applicant: Divio, Inc.Inventors: Christos Chrysafis, Siu-Leong Yu
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Publication number: 20040230419Abstract: To encode an audio signal xn, N samples of the audio signal is taken during each period of the signal (i.e., n varies from 0 to N-1) and are stored in a memory, such as a DRAM. The indices of the input samples (i.e., coefficients) are divided into T groups such that M of these coefficients each associated with a different one of the indices of each of the T groups may be read from the DRAM in a burst read operation. The M coefficients read during each burst operation are stored in a second memory in a burst write operation. Thereafter, each T time-domain coefficients whose indices belong to the same group are used to compute a first set of complex numbers ƒs which are subsequently used to encode the signal. Because the read and write operations are carried out using burst modes, the number of memory accesses is reduced, thereby improving efficiency and reducing cost.Type: ApplicationFiled: May 15, 2003Publication date: November 18, 2004Applicant: Divio, Inc.Inventors: Christos Chrysafis, Siu-Leong Yu, Charlie Cheng
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Patent number: 6701020Abstract: A method, system and program product for compressing a compound image, comprising forming compound image data into a plurality of blocks; obtaining classifying data that designate one from a plurality of classes for each of a plurality of said blocks, based on predominate compression properties of the block; for each of a plurality of said blocks, obtaining transformed data therefor from either a lossy or a lossless transform selected based on the classifying data for the block; and forwarding that transformed data to one entropy encoder. In one embodiment, obtaining transformed data comprises obtaining transformed data from at least one of a lossy transform, a first lossless transform, or a second lossless transform, based on the classifying data for the transform.Type: GrantFiled: March 15, 2001Date of Patent: March 2, 2004Assignee: Hewlett-Packard Development Company, L.P.Inventors: Christos Chrysafis, Amir Said
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Publication number: 20030202588Abstract: To encode an unencoded block of a frame, a search window is defined within the frame. Each pixel disposed within the search window and disposed in the unencoded portion of the frame that is assigned a value. A difference is computed between the unencoded block and each possible block within the search window. The block having the smallest difference, together with this difference are used to encode the unencoded block.Type: ApplicationFiled: April 25, 2003Publication date: October 30, 2003Applicant: Divio, Inc.Inventors: Siu-Leong Yu, Christos Chrysafis
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Patent number: 6546143Abstract: A subband decomposition of an image is performed by filtering the image in a progression of N line windows. In a first filter stage, vertical filters perform high and low pass filtering on each N line window. Then horizontal filtering is performed on the output of each vertical filter. The lowest subband provided by the filter stage is recursively decomposed by additional filter stages. Higher subbands of each filter stage are encoded and placed in an embedded bitstream. Block encoding can be performed in which a number of lines of each subband are coded as a plurality of blocks. The blocks of a subband are coded independently of each other. The block coding supports region-of-interest reconstruction.Type: GrantFiled: March 12, 1999Date of Patent: April 8, 2003Assignee: Hewlett-Packard Development CompanyInventors: David S. Taubman, Christos Chrysafis, Erik Ordentlich
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Publication number: 20020176632Abstract: A method, system and program product for compressing a compound image, comprising forming compound image data into a plurality of blocks; obtaining classifying data that designate one from a plurality of classes for each of a plurality of said blocks, based on predominate compression properties of the block; for each of a plurality of said blocks, obtaining transformed data therefor from either a lossy or a lossless transform selected based on the classifying data for the block; and forwarding that transformed data to one entropy encoder. In one embodiment, obtaining transformed data comprises obtaining transformed data from at least one of a lossy transform, a first lossless transform, or a second lossless transform, based on the classifying data for the transform.Type: ApplicationFiled: March 15, 2001Publication date: November 28, 2002Inventors: Christos Chrysafis, Amir Said