Inventors list

Assignees list

Classification tree browser

Top 100 Inventors

Top 100 Assignees


Dake He

Dake He, Waterloo CA

Patent application numberDescriptionPublished
20090323798METHOD AND SYSTEM FOR LOW-COMPLEXITY SLEPIAN-WOLF RATE ESTIMATION IN WYNER-ZIV VIDEO ENCODING - A method and system for low-complexity Slepian-Wolf rate estimator in a hybrid Wyner-Ziv video encoder determines the minimum Slepian-Wolf code rate required to allow correct decoding. The Slepian-Wolf estimator does not assume ideality of source and side-information statistics and does not require the presence of a feedback channel from the decoder to the encoder in order to determine the correct Slepian-Wolf coding rate. Instead, it adapts to the statistical properties of the video steam. The Slepian-Wolf estimator provides very efficient compression performance while avoiding Slepian-Wolf decoding failures.12-31-2009
20100095116Method and System for Secure Collaboration Using Slepian-Wolf Codes - A method and system provide for secure sharing of arbitrary data between users with limited mutual trust. A user can encode its information by using a Slepian-Wolf code at a rate which enables a second user to correctly decode only if the side-information it has satisfies a conditional entropy constraint. The key advantages are as follows. Firstly, it is very flexible, in that it enables secure sharing for general data including multimedia data. Secondly, by appropriate Slepian-Wolf code selection, it enables compression in conjunction with security. Thirdly, it can be used for the case where the data model is imperfectly known and trust is to be built up incrementally.04-15-2010
20100123607METHOD AND SYSTEM FOR EFFICIENT DATA TRANSMISSION WITH SERVER SIDE DE-DUPLICATION - The invention provides a method and system for reducing redundant data blocks. The method includes encoding a first data block having a first length into a bitstream having a second length, transmitting the bitstream to a server device, and reducing redundant data blocks by decoding the first data block from a first plurality of data blocks and the bitstream where each block in the first plurality of data blocks has a length equal to the first length.05-20-2010
20100188273METHOD AND SYSTEM FOR EFFICIENT DATA TRANSMISSION WITH SERVER SIDE DE-DUPLICATION - The invention provides a method and system for reducing redundant data blocks. The method includes reducing redundant data blocks by decoding a first data block from a first plurality of data blocks and a bitstream.07-29-2010
20100208804MODIFIED ENTROPY ENCODING FOR IMAGES AND VIDEOS - A method and encoder for entropy encoding image data using a dynamically determined coding order, and a method and decoder for entropy decoding encoded data encoded using a dynamically determined coding order. The coding order for encoding quantized transform domain coefficients is dynamically determined for the image based on at least one characteristic of the quantized transform domain coefficients. The characteristic may be quantization step size if non-uniform quantization is employed for blocks of data.08-19-2010
20100208805ADAPTIVE QUANTIZATION WITH BALANCED PIXEL-DOMAIN DISTORTION DISTRIBUTION IN IMAGE PROCESSING - Methods and encoders and decoders for adaptively quantizing transform domain coefficients in image and/or video encoding/decoding. For an image having a number of blocks, each block having N coefficients, the quantization step size for each coefficient is selected dynamically, thus resulting in a quantizer that may apply different step sizes to different coefficients. The selected step sizes for each coefficient are used for those coefficients within all blocks in the image/frame. In one aspect, the step sizes are selected on the basis of balancing pixel domain distortion when the image/frame is decoded.08-19-2010
20100208806IN-LOOP DEBLOCKING FOR INTRA-CODED IMAGES OR FRAMES - Methods and encoders/decoders for applying in-loop deblocking to intra-coded images/frames. In a decoding context, a deblocking filter is applied to reconstructed pixels of an intra-coded block prior to decoding the subsequent block in the decoding sequence. In an encoding context, a deblocking filter is applied to reconstructed pixels of an intra-coded block in an inter-coding loop before encoding a subsequent block in the coding order for the image.08-19-2010
20110116545METHODS AND DEVICES FOR IN-LOOP VIDEO DEBLOCKING - A video encoder sends at least some information regarding boundary strength to the decoder along with the bitstream of encoded video. The decoder is configured to use the received boundary strength information from the encoder to reduce the number of computations necessary for the decoder to determine the boundary strength details required for performing deblocking when decoding the bitstream.05-19-2011
20110170595METHOD AND DEVICE FOR MOTION VECTOR PREDICTION IN VIDEO TRANSCODING USING FULL RESOLUTION RESIDUALS - A transcoder and methods of encoding inter-prediction frames of a downsampled video wherein the downsampled video is a spatially downsampled version of a full-resolution video. Full-resolution motion vectors are downscaled and a weighting factor is calculated for each downscaled motion vector based upon the transform domain residual coefficients associated with that full-resolution motion vector. A motion vector prediction is made based on the weighted average using the downscaled motion vectors and their weighting factors.07-14-2011
20110170596METHOD AND DEVICE FOR MOTION VECTOR ESTIMATION IN VIDEO TRANSCODING USING UNION OF SEARCH AREAS - A transcoder and methods of encoding inter-prediction frames of a downsampled video wherein the downsampled video is a spatially downsampled version of a full-resolution video. Full-resolution motion vectors are downscaled and each downscaled motion vector pinpoints a search area within a reference frame. The union or combination of search areas defines the search field for candidate motion vectors. A motion vector is selected from the candidates based on realizing a minimum rate-distortion cost.07-14-2011
20110170597METHOD AND DEVICE FOR MOTION VECTOR ESTIMATION IN VIDEO TRANSCODING USING FULL-RESOLUTION RESIDUALS - A transcoder and method of transcoding in which inter-prediction frames of a downsampled video are encoded using downsampled full-resolution residuals in the rate-distortion analysis used to locate a motion vector for a given partition in the downsampled video.07-14-2011
20110170598METHOD AND DEVICE FOR VIDEO ENCODING USING PREDICTED RESIDUALS - An encoder for encoding a video by performing motion estimation using predicted residuals in the rate-distortion cost expression. The predicted residuals are determined by finding a predicted motion vector with respect to the original reference frame and calculating the corresponding residual values. The actual motion vector is then selected based on minimization of the rate-distortion cost expression with respect to the reconstructed reference frame, where the rate-distortion cost expression includes the predicted residuals. In particular, the cost expression includes reconstructed predicted residuals within the distortion term.07-14-2011
20110170608METHOD AND DEVICE FOR VIDEO TRANSCODING USING QUAD-TREE BASED MODE SELECTION - An encoder for encoding a downsampled video in which macroblock partitioning is based upon downsampled partitioning of full-resolution macroblocks. The refinement of the downsampled partitioning involves storing the downsampled partitioning in a quad-tree data structure and recursively identifying and evaluating possible mergers of leaf nodes having a common parent node. Using rate-distortion analysis possible mergers are evaluated and advantageous mergers are performed, thereby creating larger partitions and new leaf nodes. The traversing of the quad-tree to identify possible leaf node mergers is stopped when no further possible mergers may be identified that would result in a rate-distortion advantage.07-14-2011
20110184733SYSTEM AND METHOD FOR ENCODING AND DECODING PULSE INDICES - Methods, and corresponding codec-containing devices are provided that have source coding schemes for encoding a component of an excitation. In some cases, the source coding scheme is an enumerative source coding scheme, while in other cases the source coding scheme is an arithmetic source coding scheme. In some cases, the source coding schemes are applied to encode a fixed codebook component of the excitation for a codec employing codebook excited linear prediction, for example an AMR-WB (Adaptive Multi-Rate-Wideband) speech codec.07-28-2011
20110200101METHOD AND ENCODER FOR CONSTRAINED SOFT-DECISION QUANTIZATION IN DATA COMPRESSION - A method of encoding a video using constrained soft-decision quantization. The soft-decision quantization includes first performing hard-decision quantization to obtain hard quantized coefficients and, then, obtaining a soft quantized coefficient using a rate-distortion calculation over a search range of quantization levels for a transform domain coefficient, wherein the search range of quantization levels for that transform domain coefficient is constrained within a number of quantization levels of a corresponding hard quantized coefficient. The search range may be based upon a fixed threshold, the coefficient position, the hard quantized coefficient magnitude, a threshold value less accumulated distortion, or other factors, including combinations of these factors. The accumulated distortion may be measured by an L1 norm.08-18-2011
20110200104PARALLEL ENTROPY CODING AND DECODING METHODS AND DEVICES - A method for entropy coding data using parallel entropy coders to encode an input sequence as a plurality of encoded subsequences, which are then combined to form an output bitstream. The input sequence is separated into subsequences on the basis of a context model. A method for entropy decoding a bitstream of encoded data by extracting a plurality of encoded subsequences from the bitstream and entropy decoding the encoded subsequences in parallel to generate a plurality of decoded subsequences, which are then interleaved based on a context model to produce a reconstructed sequence.08-18-2011

Patent applications by Dake He, Waterloo CA

Dake He, Sichuan CN

Patent application numberDescriptionPublished
20090240394Device for Monitoring and Recording Driver's Operations and the Peripheral Scene of a Motor Vehicle - A recording device for monitoring and recording the driver's operations and the peripheral scene of a motor vehicle, comprising information acquisition units and a central processing unit. The information acquisition units capture information such as image data, while the central processing unit stores and process the information captured by the information acquisition units. The device can record the driver's operations and the peripheral scene of the motor vehicle when an accident happens. The recorded information can be used for analyzing the accident.09-24-2009

Dake He, Yorktown Heights, NY US

Patent application numberDescriptionPublished
20080219346METHOD FOR EFFICIENT ENCODING AND DECODING QUANTIZED SEQUENCE IN WYNER-ZIV CODING OF VIDEO - A computer-based method for encoding and decoding quantized sequences in Wyner-Ziv coding of video, bi-partite graph is used in an iterative process. The method takes as input to an encoder a sequence of quantized data from a finite alphabet, the sequence comprising a video frame. Another sequence of data, decoded from the prior video frame, is input to a decoder. A statistical model describing the statistical relationship between the quantized input sequence to the encoder and the input sequence to the decoder is input to both the encoder and the decoder. A minimum field size is estimated from the statistical model at the encoder and the decoder separately.09-11-2008
20080288929METHOD AND APPARATUS FOR RUN-TIME STATISTICS DEPENDENT PROGRAM EXECUTION USING SOURCE-CODING - Disclosed are a method and system for optimized, dynamic data-dependent program execution. The disclosed system comprises a statistics computer which computes statistics of the incoming data at the current time instant, where the said statistics include the probability distribution of the incoming data, the probability distribution over program modules induced by the incoming data, the probability distribution induced over program outputs by the incoming data, and the time-complexity of each program module for the incoming data, wherein the said statistics are computed on as a function of current and past data, and previously computed statistics; a plurality of alternative execution path orders designed prior to run-time by the use of an appropriate source code; a source code selector which selects one of the execution path orders as a function of the statistics computed by the statistics computer; a complexity measurement which measures the time-complexity of the currently selected execution path-order.11-20-2008
20080320363METHOD AND APPARATUS FOR RATELESS SOURCE CODING WITH/WITHOUT DECODER SIDE INFORMATION - A method of and system for rateless source coding are disclosed. The method comprises the steps of providing a set of low-density parity check (LDPC) codes, each of which accepts a range of data input lengths and a range of target compression rates; identifying a data input having a data input length; and identifying a desired compression rate. The method comprises the further steps of selecting one of said LDPC codes based on said data input length and desired compression rate; encoding the data input, using the selected LDPC code, to generate a sequence of data values; and puncturing some of said encoded data values to achieve the desired compression rate. Preferably, the encoding step includes the steps of generating a syndrome and a parity sequence from the data input, puncturing the generated parity sequence, and mixing a remaining portion of the data input with the punctuated parity sequence.12-25-2008
20090030922Method and Apparatus for Constructing Efficient Slepian-Wolf Codes With Mismatched Decoding - Disclosed is a method for constructing Slepian-Wolf codes, wherein the designed Slepian-Wolf codes are robust to mismatched decoding. The disclosed method for constructing Slepian-Wolf codes includes the steps of: choosing representative probability distributions from a set of possible probability distributions; choosing a probability distribution as a decoding metric; converting the chosen decoding metric to a cyclic-symmetric channel; computing the initial message value given the cyclic-symmetric channel; computing a set of probability distributions of the initial message given the initial message values and the representative probability distributions; optimizing the degree distribution given the set of probability distributions of the initial message; optimizing the decoding metric.01-29-2009
20090122868METHOD AND SYSTEM FOR EFFICIENT VIDEO COMPRESSION WITH LOW-COMPLEXITY ENCODER - Disclosed are a method and system for video compression, wherein the video encoder has low computational complexity and high compression efficiency. The disclosed system comprises a video encoder and a video decoder, wherein the method for encoding includes the steps of converting a source frame into a space-frequency representation; estimating conditional statistics of at least one vector of space-frequency coefficients; estimating encoding rates based on the said conditional statistics; and applying Slepian-Wolf codes with the said computed encoding rates. The preferred method for decoding includes the steps of; generating a side-information vector of frequency coefficients based on previously decoded source data, encoder statistics, and previous reconstructions of the source frequency vector; and performing Slepian-Wolf decoding of at least one source frequency vector based on the generated side-information, the Slepian-Wolf code bits and the encoder statistics.05-14-2009

Dake He, Ontario CA

Patent application numberDescriptionPublished
20110206145Methods and Apparatus for Secure Distribution and Storage of Data Using N Channels - Methods and apparatus are provided for secure distribution and storage of data using N channels. An input data sequence, X, is distributed using a plurality, N, of channels. In one embodiment, the input data sequence, X, is split into N subsequences; and the N subsequences are encoded into N bit streams using a set of Slepian-Wolf codes with N separate encoders and a joint decoder. The Slepian-Wolf codes can be selected to ensure a computational complexity to obtain a portion of the input data sequence grows exponentially with respect to a length of the input data sequence unless all of the N bit streams are compromised. In another embodiment, the input data sequence, X, is compressed using a lossless data compressing techniques; and the compressed input data sequence is split into N subsequences that are distributed.08-25-2011