Abstract: A dictionary in which a character train serving as a processing unit upon compression has been registered is stored into a character train dictionary storing unit. In a character train comparing unit, the registration character train in the character train dictionary storing unit and a partial character train in non-compression data are compared, thereby detecting the coincident partial character train. A code output unit allocates a predetermined code every partial character train detected by the character train comparing unit and outputs. The character train dictionary storing unit allocates character train codes of a fixed length of 17 bits to about 130,000 words and substantially compresses a data amount to the half or less irrespective of an amount of document data.

Abstract: A parser (100) for parsing a digital bitstream which includes both data information and programming information, where it is based on the programming information contained in the bitstream, is disclosed. The parser (100) included a buffer (110), a mode selector (200), a control circuit (300), and a data processor (400). The mode selector (200) determines whether one or more bits of the bitstream segment represent a mode selection code, and selects a parser mode in response to the mode selection code. The control circuit (300) receives and stores bits from the buffer when the bitstream parser (100) is in a program mode in order to reprogram the control circuit (300) with newly received program information, and uses the program information to generate one or more parsing signals when the bitstream parser (100) is in data mode.

Abstract: There is disclosed an apparatus for controlling the transmission of enhancement layer video data for use in a video encoder containing a base layer encoder and an enhancement layer encoder. The base layer encoder receives input video frames and generates compressed base layer video frames suitable for transmission at a base layer bit rate to a streaming video receiver. The enhancement layer encoder compares the input video frames and a processed version of the compressed base layer video frames and generates enhancement layer video data suitable for transmission at a modifiable enhancement layer bit rate to the streaming video receiver. The apparatus comprises a base layer parameter monitor for receiving at least one base layer parameter and, in response thereto, modifying an allocation of the enhancement layer video data among corresponding ones of the compressed base layer video frames.

Abstract: The present invention includes a method (500, 600, 700, 800), client device (900, 1000), server (1100, 1200) and article of manufacture (900, 1000, 1100, 1200) for compressing/decompressing a universal resource identifier URI. The method includes the steps of: determining, starting at a first end of a string, a first count of characters that sequentially match between a previous register and a current register; determining, starting at a second end of the string, a second count of characters that sequentially match between the previous register and the current register, and encoding the URI based on the first count and the second count.

Abstract: A system and method for performing trainable nonlinear prediction of transform coefficients in data compression such that the number of bits required to represent the data is reduced. The nonlinear prediction data compression system includes a nonlinear predictor for generating predicted transform coefficients, a nonlinear prediction encoder that uses the predicted transform coefficients to encode original data, and a nonlinear prediction decoder that uses the predicted transform coefficients to decode the encoded bitstream and reconstruct the original data. The nonlinear predictor may be trained using training techniques, including a novel in-loop training technique of the present invention. The present invention also includes a method for using a nonlinear predictor to encode and decode data. The method also includes improving the performance of the nonlinear prediction data compression and decompression using several novel speedup techniques.

Abstract: Apparatus and methods for reducing compression and decompression time in a computer system that selectively compresses only the data space of a storage medium 16 used for data storage without having access to internal data structures of the operating system or file system. The present invention reduces the compression and decompression time of a given data storage medium in the computer system. Compression and decompression algorithms selectively exclude a portion of the storage medium that it marks as unused space. This reduces the total time that is needed to compress and decompress the data on a storage medium that has both usable and unused data on the storage medium.

Abstract: The present invention provides for the compression of digital and analog data for storage and transmission. Analog data in the form of an analog signal is converted into a digital signal by an analog-to-digital converter. The digital signal is then converted into an analog signal having an alternating frequency by a first converter processor and an alternating frequency generator according to a predetermined conversion table. To reproduce the original analog signal, the analog signal having an alternating frequency is first converted back into a digital signal by an alternating frequency measurement means connected to a second converter processor, also in accordance with the predetermined conversion table. The digital signal is then converted to the original analog signal by a digital-to-analog converter.

Abstract: A process for converting signals in the form of digital data, such as various types of video/audio/data signals for example, between an original format, in which each data item includes a certain number of digits, and a compressed format, in which each data item includes a smaller number of digits. The process includes the operation of associating the data with a configuration including: a first field identifying the number of sub-blocks into which the said certain number of digits are subdivided, a second field that identifies, within the said sub-blocks, respective sections, each one including a given number of digits, and a third field that identifies, for each these sections, one of a plurality of applicable modes (average, compression, transmission “as is”, etc.) that can be adopted for converting the digits in the section between the original format and the compressed format.

Abstract: The present invention relates to a data compression techniques and is of particular relevance to embedded devices having a flash-prom. Data compression techniques have been known for many years. Devices such as mobile telecommunications handsets, personal digital assistants and vehicular navigation systems do not support access to data storage systems such as hard or floppy devices and their operating system and applications are typically stored on a flash-PROM that is associated with the embedded device. Flash-proms, suffer, in the main, from being rather slow. Flash-proms are also expensive. The present invention seeks to provide a data compression/decompression arrangement which can reduce flash-PROM usage without increasing boot-up time and provides a method for processing information in a data processor operable to process data to provide a sequence of uncompressed and compressed data blocks, whereby each block comprises an even number of bytes.

Abstract: A data processor uses storage units that are subdivisible into predetermined fields for executing instructions that cause the data processor to handle numbers from respective ones of the fields separately. The processor has an instruction that addresses a first and a second one of the storage units. In response the data processor takes a first and second group of successive bits from a first and second one of the fields of the first one of the storage units, places the first and second groups of successive bits at respective shifted positions both in the same field in a result storage unit, a bit position distance between the shifted positions being controlled by a content of the second one of the storage units.

Abstract: A method for generating data characterizing an item described by an ordered string of characters, comprises the steps of: (i) for a set of separation metrics each representing a unique number of positions of separation between arbitrary characters in a character group in the ordered string of characters, associating first with each separation metric; generating a set of character groups, wherein each character group comprises at least two characters contained within the ordered string of characters; and (ii) for at least one given character group in the set of character groups, for each given separation metric in the set of separation metrics, generating second data representing number of occurrences that the given character group satisfies the given separation metric; generating third data associated with the given character group, wherein the third data is based upon the second data and the first data; and storing the third data in memory for subsequent use.

Abstract: The coding mode determining section, when receiving the information as to occurrence of a scene change from the scene change detector, outputs a piece of mode control information to the coding controller. The coding controller, based on the amount of coding in the coder and the mode control information, controls the quantizer by setting up a quantization stepsize so that the current frame will have the target amount of coding. In this way, the quantization and coding are controlled by three stages, i.e., immediately after a scene change, from the scene change to the stabilization of the amount of coding, and after the stabilization of the amount of coding, to thereby prevent degradation of picture quality.

Abstract: An information processing system including a data input means (203, 208, 217, 219) for inputting or receiving data, a data compressing means (206) for compressing the data, a decompressing means (221) for decompressing the compressed data and a main storage (209, 222) is provided with an encrypting means (207) for encrypting the data and a decrypting means (220) for decrypting the encrypted data.

Abstract: A data compression and decompression system based on the LZW data compression and decompression methodology that includes exclusion tables for storing strings that are infrequently encountered. If an extended string formed for updating the compressor and decompressor dictionaries is included in the exclusion tables, the extended string is not stored and the code counter for assigning codes to dictionary strings is not advanced. In this manner, dictionary codes are not usurped by infrequently encountered strings. The exclusion tables are dynamically modified in accordance with the input data by deleting strings from the exclusion tables that are frequently encountered therein and by adding infrequently encountered strings to the exclusion tables.

Abstract: A method and a system are presented for generating differentially compressed output from binary sources. Given two versions of the same file as input streams, a compact encoding of one of the input streams is generated, by representing it as a set of changes with respect to the other input stream. Algorithms for differencing files requiring time linear in the size of the input and a constant amount of space for execution are presented. In addition, advanced techniques for improving existing differencing algorithms are developed and applied to previous methods. These techniques allow algorithms to increase their efficiency without a loss of compression and to accept arbitrarily large inputs without sacrificing correctness or degrading the compression data rate. The differential compression methods provide a computationally efficient compression technique for applications that generate versioned data.

Abstract: Hash values, keys and cipher text which have a high degree of data scrambling are generated rapidly. When a message is sent, divisional data of the message are input, and injection extension processing is performed so that the data length of output data is longer than the data length of input data. Further, hash values are generated by a hash function containing multiplication processing, cyclic shift processing, etc.

Abstract: Data elements, preferably representative of video data, are logically divided into blocks. In a bit-wise fashion, each block is inspected to determine whether the data elements for that block may be represented in a highly compact format. If a given block may not be represented in this manner, it is sub-divided into blocks having smaller dimensions. This process of identifying suitable blocks and sub-dividing is recursively repeated until minimum block dimensions are reached. The same result may be achieved through the use of a plurality of ascending tables that are constructed by repetitively forming tables of reduced data elements. The plurality of ascending tables is traversed and, based on the reduced data elements, blocks of data are identified that are susceptible to the highly compact format. Wavelet transforms are preferably used to provide video data to be compressed.

Abstract: A method, apparatus, and program storage device for supporting improved record processing protocols for COBOL SORT and MERGE functions using input and output procedures in an object program. The SORT and MERGE functions include protocols for obtaining all of the input records via an input procedure in the object program and storing them into a memory area before performing the sort or merge steps of the SORT or MERGE function. Similarly, the SORT and MERGE functions store their results into a memory area before invoking the output procedure in the object program. Also, the present invention provides an optional overflow file which is used if the memory capacity is inadequate to store and retrieve all of the requisite data.

Abstract: The present invention includes a method (700, 800, 900, 1200), client device (700, 800, 1000), server (900, 1100) and article of manufacture (700, 800, 900, 1000, 1100) for compressing/decompressing a current universal resource identifier URI using an immediately previous URI. The method for compressing the URI includes the steps of: partitioning the immediately previous URI and the current URI into a predetermined number of components; and comparing each component of the current URI with each corresponding component of the immediately previous URI from left-to-right LR and from right-to-left RL and encoding the current URI using concatenated compression indicators in accordance with counts of LR-matched characters, RL matched characters and uncompressed characters, wherein an escape byte is added to an end of the uncompressed characters when a last uncompressed character has a most significant bit set to one.

Abstract: A virtual memory manager for a multi-media engine allows individual media units to operate in their own virtual space in much the same way as a software program operating in virtual mode. The virtual memory controller performs address translation or mapping to the correct physical memory location (in local memory or system memory) and will also convert the data stream to or from a compressed format. In addition, the virtual memory controller provides a unified TLB (translation lookaside buffer) available to all media units. The TLB has four types of pointer entries which are controlled by two bits. The first bit controls whether the TLB entry is a direct map or a pointer to another translation table. the second bit controls whether the TLB entry is stored in a compressed format. The overall concept may allow dynamic load balancing between local media memory and system memory.

Abstract: A method of compressing media content in which a first predetermined portion of a media content is compressed using a first data-based compression algorithm and inserted into a first portion of a data frame. A second predetermined portion of the media content is compressed using a second data-based compression algorithm and is inserted into a second portion of the data frame. The second predetermined portion of the media content is different from the first predetermined portion of the media content, and the second data-based compression algorithm is different from the first data-based compression algorithm. At least one of the first and second data-based compression algorithms is a private data-based compression algorithm. A plurality of data frames are generated and are made available for distribution, for example, by transmission over a computer network, such as the Internet.

Abstract: A method and corresponding apparatus for compressing a binary code includes converting an initial flow of data through serial multiplication of values of bits of a signal to be coded, receiving an a coding function, and summing all products of the serial multiplication for a predetermined period of time. The method further provides that discrete values of the coding function are used as the coding function, the coding function is a piecewise continuous function in a form of a Gaussian pulse with a frequency fill, computations of a Duamel sequence are used during conversion of the code, and the initial data and discrete values of the coding function are used as arguments of the sequence.

Abstract: A high-speed method for the compression and decompression of floating point numbers. The floating point numbers are biased using a predefined value and then stored in compressed format occupying less memory than that of the non-compressed floating point numbers. Decompression of the compressed floating point number follows a reverse process. These techniques are useful with applications in which the numbers to be compressed fall within a given range.

Abstract: Rather than comparing an old file with a new file to generate a set of patching instructions, and then compressing the patching instructions to generate a compact patch file for transmission to a user, a patch file is generated in a single operation. A compressor is pre-initialized in accordance with the old version of the file (e.g. in an LZ77 compressor, the history window is pre-loaded with the file). The pre-initialized compressor then compresses the old file, producing a patch file from which the new file can be generated. At the user's computer, a parallel process is performed, with the user's copy of the old file being used to pre-initialize a decompressor to which the patch file is then input. The output of the decompressor is the new file. The patch files generated and used in these processes are of significantly reduced size when compared to the prior art.

Abstract: A high-speed method for the compression and decompression of floating point numbers. The floating point numbers are biased using a predefined value and then stored in compressed format occupying less memory than that of the non-compressed floating point numbers. Decompression of the compressed floating point number follows a reverse process. These techniques are useful with applications in which the numbers to be compressed fall within a given range.

Abstract: This method of compressing messages, in particular messages intended to be displayed on a telecommunications terminal, in particular a portable telephone, is essentially characterized in that, with said messages being made up of words themselves made up of characters, it includes compiling two encoding tables, namely an “encoding table for compressing words”, causing each compressed word represented by its rank in the table to correspond to a “semi-compressed” word made up of a sequence of compressed characters corresponding to the word, and an “encoding table for compressing characters”, causing each compressed character represented by its rank in the table to correspond to a non-compressed character.

Abstract: A method for generating a compressed or expanded waveform from original waveform data is disclosed. A plurality of frequency band-divided waveform data is generated from the original waveform data. Phase and amplitude data having periodically changing amplitudes are extracted for each of the plurality of frequency band-divided waveform data. The periodically changing phase data is converted to periodically changing frequency data, and a temporal change rate of the periodically changing amplitude and frequency data is adjusted for each of the plurality of frequency band-divided waveform data. The temporally adjusted amplitude and frequency data for the plurality of frequency band-divided waveform data is then combined to generate the compressed or expanded waveform.

Abstract: A converter (130) comprises a multiplex-buffer (410) at a bus (120), a decoder (420), an output buffer (430) and a comparator (440). The multiplex-buffer (410) forwards VMAX bits (260) of Huffman coded code portions (222) from the bus (120) to the decoder (410). The VMAX bits (260) can comprise further bits set to logical “1” or “0” at random. On a control output (414), the multiplex-buffer (410) provides a signal K identifying which of the VMAX bits are valid or invalid. The decoder (420) maps the VMAX bits (260) into a preliminary bit cluster (426) and indicates a code length V regardless whether some or all bits are valid or not. The comparator (440) checks V and K and allows the output buffer (430) to copy the preliminary bit cluster (426) into instruction portions (212) only when the code length fits the identification of valid bits.

Abstract: An information processing system including a data input means (203, 208, 217, 219) for inputting or receiving data, a data compressing means (206) for compressing the data, a decompressing means (221) for decompressing the compressed data and a main storage (209, 222) is provided with an encrypting means (207) for encrypting the data and a decrypting means (220) for decrypting the encrypted data.

Abstract: A method and apparatus for performing simultaneous data compression and encryption both compresses and encrypts data in a single step. The invention includes a novel modeling method for use in conjunction with a coder, such as an arithmetic coder. The modeling method introduces randomness into the compression process, with the result that the output stream is secure.

Abstract: The real time compression of moving images employing vector quantization is realized using simple hardware and with an optimal compression ratio with respect to the communication line capacity employed.

Abstract: A method for compressing data within a data processing system is disclosed. Each unit of data is at least two bytes. As each byte from a data stream is received, a determination is made as to whether or not an identical data byte occurs at a pre-selected interval within a group of bytes already received. In response to a determination that an identical data byte occurs at a pre-selected interval within a group of bytes already received, only a portion of a subsequent unit of data from the data stream is passed to an output.

Abstract: A programmable data communications device is provided to process multiple streams of data according to multiple protocols. The device is equipped with a co-processor including multiple, programmable processors allowing data to be operated on by multiple protocols. The programmable processors within the co-processor include extended instruction sets including instructions providing the operations of zero stuffing, CRC computation, partial compare, conditional move, and trie traversal. These instructions allow the processor(s) of the co-processor to more efficiently execute programs implementing data communications protocols. Since each processor is programmable, protocols standards which change may be accommodated. A network device equipped with the co-processor can handle multiple simultaneous streams of data and can implement multiple protocols on each data stream. The protocols can execute within the co-processor either independently of each other, or in conjunction with each other.

Abstract: The present invention comprises a system for efficiently using non-volatile memory in an embedded system. The system of the present invention includes an embedded system having a processor, a volatile memory, and a non-volatile memory. A decompression algorithm is stored in the non-volatile memory along with a main program. When the embedded system is powered up, the decompression algorithm is executed by the processor. The decompression algorithm operates on compressed software stored in the non-volatile memory. The compressed software includes data needed to initialize the main program. After the operation of the algorithm, the decompressed software is loaded into the volatile memory, thereby initializing the main program. Since the software for initializing the main program is stored in non-volatile memory in a compressed state, and since the decompression algorithm is compact, the present invention efficiently utilizes non-volatile memory space.

Abstract: A method and apparatus for compression and filtering of data associated with spectrometry. The method and apparatus serves to recognize peak events and filter data associated with background noise, thereby reducing the volume of data to be transferred to storage and the data transfer rate required for storing the desired data. The method of the present invention monitors the value of each data point as it is encountered and compares it to the previously encountered data to determine whether it is on or very near a peak. The y values for each data point are continuously summed and averaged to determine the average background level. The deviation .delta..sub.i is determined for each subsequent data point and is used to determine a threshold. Each subsequent data point is compared to the threshold and, if found to be above the threshold, is assumed to be part of or very near a peak. At this point, the averaging is stopped until a subsequent data point is determined to be below the threshold.

Abstract: A circuit for applying a predetermined algorithm to an input signal, has an input for receiving the input signal, a signal processing device for processing the input signal in accordance with the predetermined algorithm, and a device for outputting the processed signal. The signal processing device incorporates distributed bit-serial logic circuits to implement the predetermined algorithm.

Abstract: A modelling technique for compact representation of related images is disclosed. The images are described as collections of spatial segments, each of which is modelled with a multivariate bi-linear model in the intensity and similarity also in the address domain. As applied to digitized video sequences, each bi-linear model consists of a set of spatial change patterns relative to a reference and a set of corresponding temporal scores that indicate how much of each change pattern is present in each image. Both the structure of the encoding and decoding algorithms and also the data structure of the compact representation are disclosed. This multi-domain modelling allows efficient data representation by removal of redundancies in the spatial, temporal and other domains.

Abstract: When a weighted calculation in which a cosine-transformed coefficient is multiplied with diagonal matrixes from the right and left direction is carried out, a new transform matrix is obtained by previously multiplying a weighting diagonal matrix and the cosine transform matrix and input data is transformed by using the new transform matrix. Thus, a circuit scale can be reduced, the processing steps can be simplified, and the cost can be reduced. When a weighted calculation in which a cosine transformed coefficient C is multiplied with a diagonal matrix W from the right and left directions is carried out, the weighted cosine transform is carried out by using a new transform matrix Fw which results from previously multiplying the weighting diagonal matrix W and the cosine transform matrix F.

Abstract: An adaptive compression technique which is an improvement to Lempel-Ziv (LZ) compression techniques, both as applied for purposes of reducing required storage space and for reducing the transmission time associated with transferring data from point to point. Pre-filled compression dictionaries are utilized to address the problem with prior Lempel-Ziv techniques in which the compression software starts with an empty compression dictionary, whereby little compression is achieved until the dictionary has been filled with sequences common in the data being compressed. In accordance with the invention, the compression dictionary is pre-filled, prior to the beginning of the data compression, with letter sequences, words and/or phrases frequent in the domain from which the data being compressed is drawn. The letter sequences, words, and/or phrases used in the pre-filled compression dictionary may be determined by statistically sampling text data from the same genre of text.

Abstract: A computer system to compress bit formats provided in a first packed data sequence. The computer system include a processor, a multimedia input device to receive an image or audio input, a memory having stored thereon a set of packed data sequences having data elements representing the input, and a compression routine for manipulating the input. When the compression routine is executed by the processor, the routine causes the processor to: generate a second packed data sequence by copying the first packed data sequence; mask a portion of the first packed data sequence; shift data elements of the first packed data sequence, in response to executing a single first instruction, wherein the data elements are independently shifted by separate shift counts; mask a portion of the second packed data sequence; and generate a final result by joining the second and first packed data sequences.