Patents by Inventor Yoshiyuki Okada

Yoshiyuki Okada 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).

  • Patent number: 6281919
    Abstract: In order to carry out histogram control so that colors of regions printed for overlapping regions are appropriate for a multi-color, multi-stencil thermal silkscreen stencil-making device, a hue, printing density and corresponding extracted color for ink used in multi-color, multi-stencil printing are inputted, of which a color of the densest printing density is set at a color separation circuit 36 as an extracted color for making a histogram. A histogram producing circuit 34 constituting a histogram controller 33 is then initialized, histogram data HD for the color extracted for making a histogram is acquired while reading an original, and this histogram data HD is temporarily stored in memory 37. While stencils are being made for all of the colors, the stencils are made while an energy control circuit 35 carries out histogram control based on an applied energy control signal S corresponding to histogram data HD stored in the memory 37 and binary data D3.
    Type: Grant
    Filed: February 14, 2000
    Date of Patent: August 28, 2001
    Assignee: Riso Kagaku Corporation
    Inventor: Yoshiyuki Okada
  • Patent number: 6215906
    Abstract: For handling data having a fixed-order context, a data compression system uses a pipeline control unit to enable an occurrence frequency modeling unit and entropy coding unit to operate in pipelining. A data restoration system uses a pipeline control unit to enable an entropy decoding unit and occurrence frequency modeling unit to operate in pipelining. For handling data having a blend context, occurrence frequency modeling units associated with orders are operated in parallel for data compression or data restoration. Furthermore, word data is separated byte by byte, and byte data items are encoded or restored on the basis of the correlation thereof in a word-stream direction.
    Type: Grant
    Filed: July 30, 1999
    Date of Patent: April 10, 2001
    Assignee: Fujitsu Limited
    Inventor: Yoshiyuki Okada
  • Patent number: 6061398
    Abstract: A data compression apparatus is capable of compressing data at a high compression rate and at a high speed. A data decompression apparatus is used in combination with this data compression apparatus to decode the compressed data. The data compression apparatus includes a RAM which stores Huffman code trees each of which corresponds to a character string, i.e. "context." A CPU encodes each character which is to be encoded by use of a Huffman code tree corresponding to the context at that time. Each time a character is encoded, the Huffman code tree used is reconstructed so as to account for the encoded character. The data decompression apparatus stores Huffman code trees corresponding to contexts respectively, decodes the code to be decoded by use of a Huffman code tree corresponding to the context (a character string previously decoded). Each time one character is decoded, the Huffman code tree used for decoding is reconstructed so as to account for the decoded character.
    Type: Grant
    Filed: November 14, 1996
    Date of Patent: May 9, 2000
    Assignee: Fujitsu Limited
    Inventors: Noriko Satoh, Yoshiyuki Okada, Shigeru Yoshida
  • Patent number: 6026198
    Abstract: For handling data having a fixed-order context, a data compression system uses a pipeline control unit to enable an occurrence frequency modeling unit and entropy coding unit to operate in pipelining. A data restoration system uses a pipeline control unit to enable an entropy decoding unit and occurrence frequency modeling unit to operate in pipelining. For handling data having a blend context, occurrence frequency modeling units associated with orders are operated in parallel for data compression or data restoration. Furthermore, word data is separated byte by byte, and byte data items are encoded or restored on the basis of the correlation thereof in a word-stream direction.
    Type: Grant
    Filed: December 27, 1996
    Date of Patent: February 15, 2000
    Assignee: Fujitsu Limited
    Inventor: Yoshiyuki Okada
  • Patent number: 5956733
    Abstract: In response to a forming request, an archiver forming module compresses a data file on a network and stores into an archiver. In response to a referring request, an archiver referring module reads out the compressed data file from the archiver, reconstructs on the network, and stores the reconstructed data file into the archiver. An archiver managing module concentratedly manages the archiver on the network. An archiver concentration type processing apparatus in a sharing group is set to a host and remaining archiver distribution type processing apparatuses are set to clients. The archiver, archiver forming module, and archiver referring module are arranged in each of the host and the clients. Concentration processes and distribution processes are allowed to mixedly exist on the network.
    Type: Grant
    Filed: March 6, 1997
    Date of Patent: September 21, 1999
    Assignee: Fujitsu Limited
    Inventors: Yasuhiko Nakano, Yoshiyuki Okada
  • Patent number: 5907637
    Abstract: A method and an apparatus for compressing and decompressing data employ a splay coding instead of an arithmetic coding to achieve a high speed code entering process. The data compressing apparatus encoding input data according to a history of occurrence of the input data in the past to compress it, includes a pre-data retaining unit retaining a context, a history retaining unit retaining a combination of input data and a context, a code tree retaining unit retaining code trees each independent for each context, a code tree determining unit determining a code tree, a code outputting unit outputting unique data according to bifurcation from a node on the code tree, a code tree rearrangement unit exchanging an encoded leaf with another leaf or an internal node, and a pre-data updating unit entering the data in the pre-data retaining unit.
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: May 25, 1999
    Assignee: Fujitsu Limited
    Inventors: Kimitaka Murashita, Yoshiyuki Okada, Shigeru Yoshida
  • Patent number: 5889481
    Abstract: A compressing apparatus separates a data string inputted from source data of a Unicode in which different languages mixedly exist into a language string of each language and, after that, compresses the data string every language string. When decompressing, each language string is decompressed from the compressed data of every different language and the original data string in which a plurality of kinds of language codes mixedly exist is decompressed by using language change information obtained upon compression. In case of special language source data, for example, Japanese source data, the compression and decompression are separately executed for every different byte construction. The compression and decompression are also separately executed for every character kind in the code. Further, the compression and decompression can be also performed by unifying the byte construction.
    Type: Grant
    Filed: July 17, 1996
    Date of Patent: March 30, 1999
    Assignee: Fujitsu Limited
    Inventor: Yoshiyuki Okada
  • Patent number: 5854597
    Abstract: In a document managing apparatus for forming a compressed document file where a keyword retrieval is available, a first process operation and a second process operation are alternately executed. In the first process operation, when document data to be compressed is given, the respective characters are directly written into a compressed document file until an end control character string appears in this document data. In the second process operation, data obtained by coding the respective characters are written into the compressed document file until a start control character series appears in the document data. Also, in this document managing apparatus, a third process operation and a fourth process operation are alternately performed, when the compressed document file is restored. In the third process operation, the respective data (characters) are directly outputted until the end control character string appears in the data contained in the compressed document file.
    Type: Grant
    Filed: January 22, 1997
    Date of Patent: December 29, 1998
    Assignee: Fujitsu Limited
    Inventors: Kimitaka Murashita, Shigeru Yoshida, Yoshiyuki Okada
  • Patent number: 5844508
    Abstract: A data compression and decompression apparatus and method providing a high compression ratio. The data compressing apparatus includes, for example, an obtaining section, a first coding section, a first controlling section, a judging section, a second coding section, and a second controlling section. Characters are obtained one after another from a compression target. A code is then output corresponding to the character when the character and a predetermined number of characters are not identical. Subsequently, the number of characters obtained are counted when the character and the predetermined number of characters are identical, and a code corresponding to the number of characters counted is output when the character obtained is not identical with the predetermined number of characters.
    Type: Grant
    Filed: October 17, 1996
    Date of Patent: December 1, 1998
    Assignee: Fujitsu Limited
    Inventors: Kimitaka Murashita, Yoshiyuki Okada, Shigeru Yoshida
  • Patent number: 5825315
    Abstract: Data coding apparatus and decoding apparatuses to encode and decode data at a high speed. A data coding apparatus provided with a code table in which ranks and codes are made corresponding so that a code length becomes larger as the rank becomes lower. A rank holding unit is stored with a corresponding relationship between the character and the rank relative to each context. When the character to be encoded is input, the rank holding unit outputs a rank of that character relative to the context at that time, and the code corresponding to the rank within the code table is output by the rank coding unit. The data coding apparatus is constructed to change the rank of the character used for outputting within the rank holding unit up to a higher rank.
    Type: Grant
    Filed: December 2, 1996
    Date of Patent: October 20, 1998
    Assignee: Fujitsu Limited
    Inventors: Kimitaka Murashita, Shigeru Yoshida, Yoshiyuki Okada
  • Patent number: 5813011
    Abstract: A compressed file consists of: a header that carries information showing the position of a compression management table; compressed codes; and the compression management table that holds information showing the storage location of the compressed code of each original record. In a preferred mode, compression and decompression of data and access to compressed data are performed using input/output functions within an input/output function library so that the user need not be aware of the compression and decompression operations and the storage location of compressed data. In a further preferred mode, with these input/output functions it is judged whether a file being accessed is a compressed file or not, and if it is a compressed file, the operation is switched to input/output functions for a compressed file.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: September 22, 1998
    Assignee: Fujitsu Limited
    Inventors: Shigeru Yoshida, Masanaga Tokuyo, Yoshiyuki Okada
  • Patent number: 5801648
    Abstract: A data compressing method involves the use of a data string registering unit for registering a charactor or charactor string and the context and a code information registering unit for registering coding information of the character or character string following the context, the coding information following previous a input data. The data compressing method includes a data string new registering step of, when the input character or character string and the context set is not registering in the string registering unit, register the set in the data string registering unit.
    Type: Grant
    Filed: December 15, 1995
    Date of Patent: September 1, 1998
    Assignee: Fujitsu Limited
    Inventors: Noriko Satoh, Yoshiyuki Okada, Shigeru Yoshida, Hironori Yahagi
  • Patent number: 5796356
    Abstract: In a data compressing apparatus, when a data input unit inputs unit data, a coding unit obtains an order corresponding to the input unit data and outputs a code corresponding to this order with reference to a compression table. When completing this coding process, a compression table updating unit changes the order of the unit data in the compression table in a self-organizing manner based on only that order. In a data restoring apparatus, when a code input unit inputs the code as a result of the compression, a data restoring unit obtains another corresponding to the inputted code and outputs the unit data corresponding to this order with reference to a restoration table. When completing this coding process, a restoration table updating unit changes the order of the unit data in the restoration table in the self-organizing manner based on only that order.
    Type: Grant
    Filed: November 2, 1995
    Date of Patent: August 18, 1998
    Assignee: Fujitsu Limited
    Inventors: Yoshiyuki Okada, Noriko Satoh
  • Patent number: 5781296
    Abstract: A fiber optic gyro can overcome the defects encountered with conventional fiber optic gyros of phase-modulation method, closed-loop system with serrodyne modulation and digital modulation. A reference phase difference .DELTA..beta. and a ramp phase difference .sigma. are generated in an interference light intensity signal I by use of a triangular waveform, i.e., delta serrodyne waveform signal. The reference phase difference .DELTA..beta. is changed to constant values .DELTA..beta..sub.A and .DELTA..beta..sub.B whose absolute values are the same and whose signs are different at every times T.sub.A and T.sub.B. A phase x of the interference light intensity signal I becomes equal to x=.DELTA..theta.+.sigma.+.DELTA..beta.. The ramp phase difference .sigma. is controlled so as to satisfy .DELTA..theta.+.sigma.=0. Accordingly, at the stable point of the control loop, a Sagnac phase difference .DELTA..theta. is equal to the ramp phase difference .sigma..
    Type: Grant
    Filed: July 23, 1996
    Date of Patent: July 14, 1998
    Assignee: Tokimec Inc.
    Inventors: Kanshi Yamamoto, Shinichi Kawada, Takeshi Hojo, Yoshiyuki Okada, Isao Masuzawa
  • Patent number: 5717393
    Abstract: The present invention provides a plurality of code tables such as a high-usage code table and a low-usage code table in an entropy coding unit, and transforms a block-sorted last character string from a block-sorting transforming unit into an MTF code string in an MTF transforming unit. The entropy coding unit switches the code tables at a discontinuous part of the MTF code string to perform entropy coding. In addition, the present invention stores reference lists, whose number is equal to the number of kinds of used characters, in a reference list memory. The MTF transforming unit selects a reference list corresponding to a first character of the block-sorted character string to perform an MTF transformation.
    Type: Grant
    Filed: July 19, 1996
    Date of Patent: February 10, 1998
    Assignee: Fujitsu Limited
    Inventors: Yasuhiko Nakano, Kimitaka Murashita, Yoshiyuki Okada, Shigeru Yoshida, Masanaga Tokuyo
  • Patent number: 5673042
    Abstract: The present invention relates to a method of and an apparatus for compressing/decompressing data, to improve the compression ratio of sliding-dictionary-type Ziv-Lempel codes. A sliding-dictionary-type data compression method finds a matching character string in a coding character string and in a coded character string stored in a dictionary 101. According to the length of the matching character string, the method chooses a raw data mode that codes the matching character string that must consist of a single character as it is, or a reproduction mode that codes the position and length in the dictionary 101 of the matching character string. The method allocates consecutive numbers to different codes to be prepared under the raw data mode and reproduction mode.
    Type: Grant
    Filed: March 16, 1995
    Date of Patent: September 30, 1997
    Assignee: Fujitsu Limited
    Inventors: Shigeru Yoshida, Yoshiyuki Okada, Yasuhiko Nakano, Hironori Yahagi
  • Patent number: 5650783
    Abstract: A device for coding a series of symbols based on a multi-level arithmetic coding scheme includes a coding unit for coding the symbols based on frequency of occurrence of the symbols and orders of the symbols according to the frequency of occurrence, a context holding unit for storing the frequency of occurrence and the orders, a context updating unit for updating the frequency of occurrence and the orders upon receiving a control signal, and a controlling unit for sending the control signal when one of the symbols is coded and a cumulative frequency is less than a predetermined value, wherein the cumulative frequency is a sum of the frequency of occurrence for all of the symbols.
    Type: Grant
    Filed: September 8, 1995
    Date of Patent: July 22, 1997
    Assignee: Fujitsu Limited
    Inventors: Kimitaka Murashita, Yoshiyuki Okada, Shigeru Yoshida
  • Patent number: 5511137
    Abstract: A process and apparatus for determining values of new pixels which are to be interpolated between original pixels of an image during magnification of the image. The interpolation is carried out in each unit area which is surrounded by original pixel centers.
    Type: Grant
    Filed: October 31, 1994
    Date of Patent: April 23, 1996
    Assignee: Fujitsu Limited
    Inventor: Yoshiyuki Okada
  • Patent number: 5254990
    Abstract: In a data compressing and decompressing apparatus, having improved efficiency and enhanced compression ratio whereby character sequence of received data is coded and decoded by referring to a dictionary related to the last character of the immediately preceding character sequence, and a character sequence which is one character extended character sequence of the coded and decompressed character sequence is registered in the dictionary in relation with the last character of the immediately preceding character sequence so that the compression ratio of the coding of data is increased.
    Type: Grant
    Filed: January 11, 1993
    Date of Patent: October 19, 1993
    Assignee: Fujitsu Limited
    Inventors: Shigeru Yoshida, Yasuhiko Nakano, Yoshiyuki Okada, Hirotaka Chiba
  • Patent number: 5150119
    Abstract: In a data compression method based on an LZW coding procedure, a list which defines a sequence of tracing partial strings registered in a dictionary is modified so that a position of a first registered partial string among the registered partial strings in a tree structure of registered partial strings is interchanged with a position of a second registered partial string among the registered partial strings in a state where the first and second registered partial strings extend from an identical node of the tree structure.
    Type: Grant
    Filed: August 13, 1991
    Date of Patent: September 22, 1992
    Assignee: Fujitsu Limited
    Inventors: Shigeru Yoshida, Yoshiyuki Okada, Yasuhiko Nakano, Hirotaka Chiba