28735results about "Code conversion" patented technology

Disclosed is a method and apparatus of securely providing data to a user's system. The data is encrypted so as to only be decryptable by a data decrypting key, the data decrypting key being encrypted using a first public key, and the encrypted data being accessible to the user's system, the method comprising the steps of: transferring the encrypted data decrypting key to a clearing house that possesses a first private key, which corresponds to the first public key; decrypting the data decrypting key using the first private key; re-encrypting the data decrypting key using a second public key; transferring the re-encrypted data decrypting key to the user's system, the user's system possessing a second private key, which corresponds to the second public key; and decrypting the re-encrypted data decrypting key using the second private key.

The present invention relates to a system for (1) protecting the transmission of packet streams between a host computer and one or more client computers, and (2) upon reception, (a) reconstructing any outage damage caused during the transmission to the packet streams, and (b) digitally recording the reconstructed packet streams to a file. The present invention also relates to a method for dynamically generating a file index table as the packet stream is being digitally recorded.

The invention discloses a data validation, mirroring and error / erasure correction method for the dispersal and protection of one and two-dimensional data at the micro level for computer, communication and storage systems. Each of 256 possible 8-bit data bytes are mirrored with a unique 8-bit ECC byte. The ECC enables 8-bit burst and 4-bit random error detection plus 2-bit random error correction for each encoded data byte. With the data byte and ECC byte configured into a 4 bit×4 bit codeword array and dispersed in either row, column or both dimensions the method can perform dual 4-bit row and column erasure recovery. It is shown that for each codeword there are 12 possible combinations of row and column elements called couplets capable of mirroring the data byte. These byte level micro-mirrors outperform conventional mirroring in that each byte and its ECC mirror can self-detect and self-correct random errors and can recover all dual erasure combinations over four elements. Encoding at the byte quanta level maximizes application flexibility. Also disclosed are fast encode, decode and reconstruction methods via boolean logic, processor instructions and software table look-up with the intent to run at line and application speeds. The new error control method can augment ARQ algorithms and bring resiliency to system fabrics including routers and links previously limited to the recovery of transient errors. Image storage and storage over arrays of static devices can benefit from the two-dimensional capabilities. Applications with critical data integrity requirements can utilize the method for end-to-end protection and validation. An extra ECC byte per codeword extends both the resiliency and dimensionality.

A file protection scheme for fixed content in a distributed data archive uses computations that leverage permutation operators of a cyclic code. In an illustrative embodiment, an N+K coding technique is described for use to protect data that is being distributed in a redundant array of independent nodes (RAIN). The data itself may be of any type, and it may also include system metadata. According to the invention, the data to be distributed is encoded by a dispersal operation that uses a group of permutation ring operators. In a preferred embodiment, the dispersal operation is carried out using a matrix of the form [IN<sub2>—< / sub2>C] where IN is an n×n identity sub-matrix and C is a k×n sub-matrix of code blocks. The identity sub-matrix is used to preserve the data blocks intact. The sub-matrix C preferably comprises a set of permutation ring operators that are used to generate the code blocks. The operators are preferably superpositions that are selected from a group ring of a permutation group with base ring Z2.

Techniques for detecting and correcting burst errors in data bytes formed in a two-level block code structure. A second level decoder uses block level check bytes to detect columns in a two-level block code structure that contain error bytes. The second level decoder generates erasure pointers that identify columns in the two-level block structure effected by burst errors. A first level decoder then uses codeword check bytes to correct all of the bytes in the columns identified by the erasure pointers. The first level decoder is freed to use all of the codeword check bytes only for error byte value calculations. The first level decoder does not need to use any of the codeword check bytes for error location calculations, because the erasure pointers generated by the second level decoder provide all of the necessary error locations. This techniques doubles the error correction capability of the first level decoder.

A method to automatically retrieve data associated with content. An identifier is read that is stored on electronic readable medium storing content. The identifier is used to search a database for data associated with the content. Data that is associated with the content is retrieved as guided by the database. And the data retrieved is used to create a version of the content for electronic distribution. In accordance with another aspect of the invention, a computer readable medium is described to carry out the above method.

Self-discovering transaction accelerators improve communications between a client and a server. A client directs a message to a server. A client-side transaction accelerator intercepts the message, terminates the connection with the client, and accelerates the request by replacing segments of data with references. The accelerated request is forwarded to a server-side transaction accelerator through a new connection. The server-side transaction accelerator reconstructs the message by replacing the reference with segment data in a persistent segment store accessible to the server-side transaction accelerator. The reconstructed request is then provided to the server. Accelerations may occur in any direction of communication. Persistent segment stores can be pre-populated with segment data from other transaction accelerators and anticipated transactions. The persistent segment store can store segments that are data segmented based on content of the data and can be independent of transaction protocol, application, and device.

A system for tracking usage of digital content on user devices. Content sites for distributing digital content over a computer readable medium to users. The content sites associate unique content identifier with the content associated. Electronic stores coupled to a network sell licenses to play digital content data to users. The licenses contain a unique transaction identifier for uniquely identifying the transaction, and the licenses contain a unique item identifier for uniquely identifying at least one item in the transaction. Content players, which receive from the network the licensed content data, are used to play the licensed content data. The content players produce a purchase identifier based upon the mathematical combination of the content identifier, the transaction identifier and the item identifier.

A received signal is first converted into a digital sequence that may contain "erasures" (or ambiguity symbols) as well as errors. Then iterative decoding is applied in order to eliminate or reduce the erasures. This decoding procedure works effectively with the associated transmitter that adopts a concatenation of an outer coder, a permutation and an inner coder. The principal of the invention is also applicable to a system in which the inner coder is replaced by a "digital modulator" that introduces some constraint, or a channel that introduces some memory such as partial response signaling, intersymbol interference or multipath propagation. The invention can be applied to many existing systems while maintaining "backward compatibility" in the sense that the transmitter side need not be modified.

A data processing system includes one or more nodes, each node including a memory sub-system. The sub-system includes a fine-grained, memory, and a less-fine-grained (e.g., page-based) memory. The fine-grained memory optionally serves as a cache and / or as a write buffer for the page-based memory. Software executing on the system uses n node address space which enables access to the page-based memories of all nodes. Each node optionally provides ACID memory properties for at least a portion of the space. In at least a portion of the space, memory elements are mapped to locations in the page-based memory. In various embodiments, some of the elements are compressed, the compressed elements are packed into pages, the pages are written into available locations in the page-based memory, and a map maintains an association between the some of the elements and the locations.

To achieve an image encoding apparatus that has extensibility by not limiting an image to be referenced, and that can reduce processing time satisfactorily if the processing of an ordinary frame is skipped, the apparatus of the present invention comprises: motion detecting means for detecting a motion vector for each block of a prescribed size from a reference image and an input image; weighted motion-compensation means for, based on the detected motion vector, extracting from the reference image an area of a prescribed size which is wider than the prescribed block size and which contains an area corresponding to each block of the input image, and for creating a predicted image for the input image by applying a predetermined weight to each of pixels in the wider area and by using the weighted pixels of the wider area; a predicted-image memory for storing the predicted image; encoding means for taking a residual between the stored predicted image and the input image, and for encoding the residual; and decoding means for decoding the encoded image data and thereby obtaining a reference image.

A solid state non-volatile memory unit includes, in part, an encoder, a multi-level solid state non-volatile memory array adapted to store data encoded by the encoder, and a decoder adapted to decode the data retrieved from the memory array. The memory array may be a flash EEPROM array. The memory unit optionally includes a modulator and a demodulator. The data modulated by the modulator is stored in the memory array. The demodulator demodulates the modulated data retrieved from the memory array.

Truncation reduces the available striped data capacity of all flash channels to the capacity of the smallest flash channel. A solid-state disk (SSD) has a smart storage switch salvages flash storage removed from the striped data capacity by truncation. Extra storage beyond the striped data capacity is accessed as scattered data that is not striped. The size of the striped data capacity is reduced over time as more bad blocks appear. A first-level striping map stores striped and scattered capacities of all flash channels and maps scattered and striped data. Each flash channel has a Non-Volatile Memory Device (NVMD) with a lower-level controller that converts logical block addresses (LBA) to physical block addresses (PBA) that access flash memory in the NVMD. Wear-leveling and bad block remapping are preformed by each NVMD. Source and shadow flash blocks are recycled by the NVMD. Two levels of smart storage switches enable three-level controllers.

Coding techniques for a (e.g., OFDM) communication system capable of transmitting data on a number of "transmission channels" at different information bit rates based on the channels' achieved SNR. A base code is used in combination with common or variable puncturing to achieve different coding rates required by the transmission channels. The data (i.e., information bits) for a data transmission is encoded with the base code, and the coded bits for each channel (or group of channels with the similar transmission capabilities) are punctured to achieve the required coding rate. The coded bits may be interleaved (e.g., to combat fading and remove correlation between coded bits in each modulation symbol) prior to puncturing. The unpunctured coded bits are grouped into non-binary symbols and mapped to modulation symbols (e.g., using Gray mapping). The modulation symbol may be "pre-conditioned" and prior to transmission.

Hashes are short summaries or signatures of data files which can be used to identify the file. Hashing multimedia content (audio, video, images) is difficult because the hash of original content and processed (e.g. compressed) content may differ significantly. The disclosed method generates robust hashes for multimedia content, for example, audio clips. The audio clip is divided (12) into successive (preferably overlapping) frames. For each frame, the frequency spectrum is divided (15) into bands. A robust property of each band (e.g. energy) is computed (16) and represented (17) by a respective hash bit. An audio clip is thus represented by a concatenation of binary hash words, one for each frame. To identify a possibly compressed audio signal, a block of hash words derived therefrom is matched by a computer (20) with a large database (21). Such matching strategies are also disclosed. In an advantageous embodiment, the extraction process also provides information (19) as to which of the hash bits are the least reliable. Flipping these bits considerably improves the speed and performance of the matching process.

Enrollment and authentication of a user based on a sequence of discrete graphical choices is described. A graphical interface presents various images and memory cues that a user may associate with their original graphical choices. Enrollment may require the input to have a security parameter value that meets or exceeds a threshold. An acceptable sequence of graphical choices is converted to a sequence of values and mapped to a sequence of codewords. Both a hash of the sequence of codewords and a sequence of offsets are stored for use in authenticating the user. An offset is the difference between a value and its corresponding codeword. Authentication requires the user to enter another sequence of discrete graphical choices that is approximately the same as original. The offsets are summed with the corresponding values before mapping to codewords. Authentication requires the sequence of codewords, or a hash thereof, to match.

Disclosed herein is a method and system for hardware-accelerating various data processing operations in a rule-based decision-making system such as a business rules engine, an event stream processor, and a complex event stream processor. Preferably, incoming data streams are checked against a plurality of rule conditions. Among the data processing operations that are hardware-accelerated include rule condition check operations, filtering operations, and path merging operations. The rule condition check operations generate rule condition check results for the processed data streams, wherein the rule condition check results are indicative of any rule conditions which have been satisfied by the data streams. The generation of such results with a low degree of latency provides enterprises with the ability to perform timely decision-making based on the data present in received data streams.

A method for low-density parity-check (LDPC) encoding of data comprises defining a first M×N parity check matrix; generating, based on the first parity check matrix, a second parity check matrix having an M×M triangular sub-matrix; and, mapping the data into an LDPC code word based on the second parity check matrix. The method is particularly useful for data communications applications, but may also be employed in other applications such as, for example, data storage.

A method including communicating with a content server, wherein the communication includes transmitting request data to the content server and receiving first response data associated with the request data; identifying response object data within the first response data; determining whether the response object data is to be downloaded; querying the content server for second response data that corresponds to the response object data based on the determination; transmitting the first response data to a user agent; and storing the second response data, wherein the second response data can be provided to the user agent in a subsequent request.

An memory module including parallel data compression and decompression engines for improved performance. The memory module includes MemoryF / X Technology. To improve latency and reduce performance degradations normally associated with compression and decompression techniques, the MemoryF / X Technology encompasses multiple novel techniques such as: 1) parallel lossless compression / decompression; 2) selectable compression modes such as lossless, lossy or no compression; 3) priority compression mode; 4) data cache techniques; 5) variable compression block sizes; 6) compression reordering; and 7) unique address translation, attribute, and address caches. The parallel compression and decompression algorithm allows high-speed parallel compression and high-speed parallel decompression operation. The memory module-integrated data compression and decompression capabilities remove system bottlenecks and increase performance. This allows lower cost systems due to smaller data storage, reduced bandwidth requirements, reduced power and noise.

A method for operating a memory device (24) includes encoding data using an Error Correction Code (ECC) and storing the encoded data as first analog values in respective analog memory cells (32) of the memory device. After storing the encoded data, second analog values are read from the respective memory cells of the memory device in which the encoded data were stored. At least some of the second analog values differ from the respective first analog values. A distortion that is present in the second analog values is estimated. Error correction metrics are computed with respect to the second analog values responsively to the estimated distortion. The second analog values are processed using the error correction metrics in an ECC decoding process, so as to reconstruct the data.

A data compression system and method for that is capable of detecting and eliminating repeated phrases of variable length within a window of virtually unlimited size.

A solid state non-volatile memory unit. The memory unit includes a multi-level solid state non-volatile memory array adapted to store data characterized by a first number of digital levels. The memory unit also includes an analog-to-digital converter having an input and an output. The input of the analog-to-digital converter is adapted to receive data from the multi-level solid state non-volatile memory array. The output of the analog-to-digital converter is adapted to output a digital signal characterized by a second number of digital levels greater than the first number of digital levels.

A digital television (DTV) transmitter and a method of processing data in the DTV transmitter / receiver are disclosed. In the DTV transmitter, a pre-processor pre-processes the enhanced data by coding the enhanced data for forward error correction (FEC) and expanding the FEC-coded data. A packet formatter generates one or more groups of enhanced data packets, each enhanced data packet including the pre-processed enhanced data and known data, wherein the data formatter adds burst time information into each group of enhanced data packets. And, a packet multiplexer generates at least one burst of enhanced data by multiplexing the one or more groups of enhanced data packets with at least one main data packet including the main data, each burst of enhanced data including at least one group of enhanced data packets.

Audio coding processes like quantization can cause spectral components of an encoded audio signal to be set to zero, creating spectral holes in the signal. These spectral holes can degrade the perceived quality of audio signals that are reproduced by audio coding systems. An improved decoder avoids or reduces the degradation by filling the spectral holes with synthesized spectral components. An improved encoder may also be used to realize further improvements in the decoder.