Abstract: 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.

Abstract: Isolation of faulty links in a transmission medium including a method that includes receiving an atomic data unit via a multi-link transmission medium that has a plurality of transmission links An error condition is detected and it is determined that the error condition is isolated to a single transmission link. It is determined if the single transmission link has been isolated previously as a failing transmission link a specified number of times within an interval specified by a timer. If the single transmission link has been isolated previously as a failing transmission link a specified number of times within an interval specified by a timer then: identifying the single transmission link as a faulty transmission link; resetting the timer; and outputting an identifier of the single transmission link.

Abstract: Encoding data into constrained memory using a method for writing data that includes receiving write data to be encoded into a write word, receiving constraints on symbol values associated with the write word, encoding the write data into the write word, and writing the write word to a memory. The encoding includes: representing the write data and the constraints as a first linear system in a first field of a first size; embedding the first linear system into a second linear system in a second field of a second size, the second size larger than the first size; solving the second linear system in the second field resulting in a solution; and collapsing the solution into the first field resulting in the write word, the write word satisfying the constraints on symbol values associated with the write word.

Abstract: Constrained coding to reduce floating gate coupling in non-volatile memories including a method for storing data. The method includes receiving write data to be written to a flash memory device, selecting a codeword in response to the write data, and writing the codeword to the flash memory device. The codeword is selected to reduce floating gate coupling in the flash memory device by preventing specified symbol patterns from occurring in the codeword.

Abstract: 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.

Abstract: A method, system and computer program product are disclosed for rateless compression of non-binary sources. In one embodiment, the method comprises representing a sequence of non-binary source symbols as a sequence of sets of binary values; selecting a code for compressing the sets of binary values; determining a puncturing pattern, based on the selected code; and puncturing the sets of binary values, in patterns based on the puncturing pattern, to form a sequence of unpunctured values. A sequence of computed syndromes is determined based on the sequence of non-binary source symbols; and the sequence of unpunctured values and the sequence of computed syndromes are combined to form an output stream of data representing said sequence of non-binary source symbols. In one embodiment, none of the sets of binary values is punctured completely, and, for example, each of the sets of binary values may be punctured only partially.

Abstract: A method, system and computer program product are disclosed for rateless compression of non-binary sources. In one embodiment, the method comprises representing a sequence of non-binary source symbols as a sequence of sets of binary values; selecting a code for compressing the sets of binary values; determining a puncturing pattern, based on the selected code; and puncturing the sets of binary values, in patterns based on the puncturing pattern, to form a sequence of unpunctured values. A sequence of computed syndromes is determined based on the sequence of non-binary source symbols; and the sequence of unpunctured values and the sequence of computed syndromes are combined to form an output stream of data representing said sequence of non-binary source symbols. In one embodiment, none of the sets of binary values is punctured completely, and, for example, each of the sets of binary values may be punctured only partially.

Abstract: Multi-write coding of non-volatile memories including a method that receives write data, and a write address of a memory page. The memory page is in either an erased state or a previously written state. If the memory page is in the erased state: selecting a first codeword from a code such that the first codeword encodes the write data and is consistent with a target set of distributions of electrical charge levels in the memory page; and writing the first codeword to the memory page. If the memory page is in the previously written state: selecting a coset from a linear code such that the coset encodes the write data and includes one or more words that are consistent with previously written content of the memory page; selecting a subsequent codeword from the one or more words in the coset; and writing the subsequent codeword to the memory page.

Abstract: Enhanced write performance for non-volatile memories including a memory system that includes a receiver for receiving a data rate of a data sequence to be written to a non-volatile flash memory device. The memory system also includes a physical page selector for selecting a physical address of an invalid previously written memory page from a group of physical addresses of invalid previously written memory pages located on the non-volatile memory device, and for determining if the number of free bits in the invalid previously written memory page at the selected physical address is greater than or equal to the data rate. The memory system also includes a transmitter for outputting the selected physical address of the invalid previously written memory page, the outputting in response to the physical page selector determining that the number of free bits is greater than or equal to the data rate.

Abstract: 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.

Abstract: A method, system and computer program product are disclosed for compressing encrypted data, wherein the data is encrypted by using a block encryption algorithm in a chained mode of operation, and the encrypted data is comprised of a set of N encrypted blocks, C1 . . . CN. In one embodiment, the method comprises leaving block CN uncompressed, and compressing all of the blocks C1 . . . CN in a defined sequence using a Slepian-Wolf code. In an embodiment, the data is encrypted using an encryption key K, and the compressing includes compressing all of the blocks C1 . . . CN without using the encryption key. In one embodiment, the compressing includes outputting the blocks C1 . . . CN as a set of compressed blocks CmprC1 . . . CmprCN-1, and the method further comprises decrypting CN to generate a reconstructed block {tilde over (X)}n, and decrypting and decompressing the set of compressed blocks using {tilde over (X)}n.

Abstract: A method and apparatus for decompressing data in a data-compression system with decoder-only side information is provided. In one aspect, the method comprises generating side information using a source reconstruction and decoding using the generated side information to generate a new source reconstruction. The method further includes iterating the steps of generating and decoding, the generating step using at least the new source reconstruction output by the previous decoding step, and the decoding step using the side information output by the previous generating step. The method may stop the iteration when one or more predetermined criteria are met.

Abstract: A method of and system for signal analysis includes acquiring multiple signals from the environment by using multiple sensor elements, applying a transform which combines the multiple acquired signals into a single combined signal, and reduces the number of samples in the combined signal, applying a single signal analysis and event detection operation on the resultant combined, sparse signal, and performing a complete signal analysis using multiple analysis elements for the multiple input signals only in the case where the sparse signal analysis indicates that the event of interest may be present.

Abstract: Providing increased capacity in heterogeneous storage elements including a method for storing data including a write process writing to a memory and a read process reading from the memory. Physical characteristics of memory cells in the memory support different sets of data levels. The write process takes into account the different sets of data levels when writing to the memory. The read process first obtains data in the memory and subsequently determines how to interpret the data.

Abstract: Adaptive endurance coding including a method for storing data that includes receiving write data and a write address. A compression algorithm is applied to the write data to generate compressed data. An endurance code is applied to the compressed data to generate a codeword. The endurance code is selected and applied in response to the amount of space saved by applying the compression to the write data. The codeword is written to the write address.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A method and system are disclosed for selecting a mode to encode video data. The method comprises the steps of (a) transforming a source video frame into a set of coefficients, (b) partitioning said set of coefficients into a plurality of subsets of the coefficients on the basis of probability statistics corresponding to a plurality of encoding modes, wherein each of said subsets is identified for encoding by one of the plurality of encoding modes. The method comprises the further steps of (c) for each of the plurality of subsets of coefficients, computing defined parameters of an associated probability distribution for said subset, and (d) repeating steps (b) and (c) until a predetermined termination condition is satisfied. When this predetermined termination condition is satisfied, the subsets of coefficients, as they exist at that time, are output to a video encoder, which preferably is a Wyner-Ziv encoder.

Abstract: 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.