Patents Assigned to Stac
  • Patent number: 5966905
    Abstract: A package of a continuous strip of material includes a plurality of parallel side by side stacks each containing a length of the strip, which is folded back and forth such that each folded portion of the stack is folded relative to the next portion about a line transverse to the strip and such that the side edges of the strip portions are aligned. The strip is continuous through each stack and can be connected by a splice from the end of one stack to beginning of the next stack. The package is compressed to reduce the height of the stacks and maintained in the compressed condition by an evacuated sealed bag. The package can have the stacks oriented vertically or horizontally. When the stacks are horizontal, the spliced portions are vertical and coplanar with the strips and at alternate ends. When the stacks are vertical, the spliced portions extend from the bottom of the stack along one end of the stack to the top of the next stack.
    Type: Grant
    Filed: October 9, 1997
    Date of Patent: October 19, 1999
    Assignee: Stac-Pac Technologies Inc.
    Inventors: Lawrence J. O'Connor, Mark B. Davidson, Darrell Van Mol
  • Patent number: 5956926
    Abstract: A package of a continuous strip of material includes a plurality of parallel side by side stacks each containing a length of the strip which is folded back and forth such that each folded portion of the stack is folded relative to the next portion about a line transverse to the strip and such that the side edges of the strip portions are aligned. The strip is continuous through each stack and is connected by a splice from the end of one stack to beginning of the next stack. The package can be compressed to reduce the height of the stacks and maintained in the compressed condition by an evacuated sealed bag. The package can be formed by folding a wide web of material back and forth and by slicing the folded web in a direction parallel to the sides of the web to form one or more stacks of a strip of width less than that of the web. The stack can be used to form the above package or can be used in a further processing by unfolding slitting and winding.
    Type: Grant
    Filed: September 29, 1997
    Date of Patent: September 28, 1999
    Assignees: KT Holdings, Inc., Stac-Pac Technologies, Inc.
    Inventors: Lawrence J. O'Connor, Mark B. Davidson, Darrell Van Mol
  • Patent number: 5927051
    Abstract: A package of a continuous strip of material includes a plurality of parallel side by side stacks each containing a length of the strip which is folded back and forth such that each folded portion of the stack is folded relative to the next portion about a line transverse to the strip and such that the side edges of the strip portions are aligned. The strip is continuous through each stack and is connected by a splice from the end of one stack to beginning of the next stack. The package can be compressed to reduce the height of the stacks and maintained in the compressed condition by an evacuated sealed bag. The package can have the stacks vertical or horizontal. The stacks are connected by a spliced portion so that the strip is continuous through the package. When the stacks are horizontal, the spliced portions are vertical and coplanar with the strips and at alternate ends. When the stacks are vertical, the spliced portions extend from the bottom to the top at one end of the stack.
    Type: Grant
    Filed: July 8, 1997
    Date of Patent: July 27, 1999
    Assignees: KT Holdings Inc., Stac-Pac Technologies Inc.
    Inventors: Lawrence J. O'Connor, Mark B. Davidson, Darrell Van Mol
  • Patent number: 5921064
    Abstract: A package of a continuous strip of material includes a plurality of parallel side by side stacks each containing a length of the strip which is folded back and forth such that each folded portion of the stack is folded relative to the next portion about a line transverse to the strip and such that the side edges of the strip portions are aligned. The stacks are formed in a stepped fashion, with a series of separate layers being laid down for each stack. The package can be compressed to reduce the height of the stacks and maintained in the compressed condition by an evacuated sealed bag.
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: July 13, 1999
    Assignees: KT Holdings, Inc., Stac-Pac Technologies, Inc.
    Inventor: Lawrence J. O'Connor
  • Patent number: 5907672
    Abstract: A system for backing up data from a computer disk volume at very high speed by saving a logical image copy of the volume to a backup medium such as magnetic tape. This logical image copy can later be restored in its entirety to a disk volume with a different physical geometry and flaw map in a disaster recovery mode, significantly reducing the time required for such disaster recovery compared to other backup techniques. In addition, the logical image copy on the backup medium also allows selective file restore with performance comparable to that achievable using traditional file-by-file backup/restore methods. The backup process can thus run considerably faster than conventional approaches without sacrificing the restore flexibility normally associated with those approaches.
    Type: Grant
    Filed: October 4, 1995
    Date of Patent: May 25, 1999
    Assignee: Stac, Inc.
    Inventors: John E. G. Matze, Douglas L. Whiting
  • Patent number: 5778395
    Abstract: A system for backing up files from disk volumes on multiple nodes of a computer network to a common random-access backup storage means. As part of the backup process, duplicate files (or portions of files) may be identified across nodes, so that only a single copy of the contents of the duplicate files (or portions thereof) is stored in the backup storage means. For each backup operation after the initial backup on a particular volume, only those files which have changed since the previous backup are actually read from the volume and stored on the backup storage means. In addition, differences between a file and its version in the previous backup may be computed so that only the changes to the file need to be written on the backup storage means. All of these enhancements significantly reduce both the amount of storage and the amount of network bandwidth required for performing the backup.
    Type: Grant
    Filed: October 23, 1995
    Date of Patent: July 7, 1998
    Assignee: Stac, Inc.
    Inventors: Douglas L. Whiting, Tom Dilatush
  • Patent number: 5532694
    Abstract: An apparatus and method for converting an input data character stream into a variable length encoded data stream in a data compression system. A sliding window data compression algorithm is combined with Huffman encoding on the strings and raw bytes. The Huffman table, in a compressed form, is prepended to the encoded output data. The Huffman codes representing the shortest strings encode both the string length and part of the string offset. Assigning Huffman codes to represent the combined length and offset allows the use of a smaller sliding window size without sacrificing compression ratio. The smaller window size allows implementations in software and hardware to minimize memory usage, thus reducing cost.
    Type: Grant
    Filed: July 7, 1995
    Date of Patent: July 2, 1996
    Assignee: Stac Electronics, Inc.
    Inventors: Clay Mayers, Douglas L. Whiting
  • Patent number: 5506580
    Abstract: An apparatus and method are disclosed for converting an input data character stream into a variable length encoded data stream in a data compression system. The data compression system includes a history array. The history array has a plurality of entries and each entry of the history array is for storing a portion of the input data stream. The method for converting the input data character stream includes the following steps. Performing a search in a history array for the longest data string which matches the input data string. If the matching data string is found within the history buffer, the next step includes encoding the longest matching data string found by appending to the encoded data stream a tag indicating the longest matching data string was found and a string substitution code.
    Type: Grant
    Filed: December 6, 1994
    Date of Patent: April 9, 1996
    Assignee: Stac Electronics, Inc.
    Inventors: Douglas L. Whiting, Glen A. George, Glen E. Ivey
  • Patent number: 5463390
    Abstract: An apparatus and method are disclosed for converting an input data character stream into a variable length encoded data stream in a data compression system. The data compression system includes a history array. The history array has a plurality of entries and each entry of the history array is for storing a portion of the input data stream. The method for converting the input data character stream includes the following steps. Performing a search in a history array for the longest data string which matches the input data string. If the matching data string is found within the history buffer, the next step includes encoding the longest matching data string found by appending to the encoded data stream a tag indicating the longest matching data string was found and a string substitution code.
    Type: Grant
    Filed: July 21, 1994
    Date of Patent: October 31, 1995
    Assignee: Stac Electronics, Inc.
    Inventors: Douglas L. Whiting, Glen A. George, Glen E. Ivey
  • Patent number: 5414850
    Abstract: A data compression device driver compresses and decompresses files on a disk drive in a computer system when a user copies files from a drive letter assigned to the disk drive to a drive letter assigned to the data compression device driver. Drive parameter blocks for the disk drive and for the data compression device driver contain the assigned drive letter, disk geometry information, a rebuild flag, and a pointer to the device driver. A swapping means swaps the device driver pointers in the drive parameter blocks corresponding to the disk drive and the data compression device driver. From then on, compressed data files may be accessed transparently by using the drive letter which was originally assigned to the disk drive before swapping, which now refers to the data compression device driver.
    Type: Grant
    Filed: August 23, 1991
    Date of Patent: May 9, 1995
    Assignee: STAC Electronics, Inc.
    Inventor: Douglas L. Whiting
  • Patent number: 5414425
    Abstract: An apparatus and method are disclosed for converting an input data character stream into a variable length encoded data stream and encoding the variable length encoded date stream according to byte length. A 2 byte length is encoded by 2 bits having the values "00". Encoded lengths of 3 and 4 bytes are represented respectively by 2 bits having the values "01" and "10". Byte lengths of 5 to 7 are represented by 4 bits "1100" to "1110" and so on to thereby enable an efficient procedure for encoding the length of a bit string during compression.
    Type: Grant
    Filed: May 9, 1994
    Date of Patent: May 9, 1995
    Assignee: Stac
    Inventors: Douglas L. Whiting, Glen A. George, Glen E. Ivey
  • Patent number: 5146221
    Abstract: An apparatus and method are disclosed for converting an input data character stream into a variable length encoded data stream in a data compression system. The data compression system includes a history array. The history array has a plurality of entries and each entry of the history array is for storing a portion of the input data stream. The method for converting the input data character stream includes the following steps. Performing a search in a history array for the longest data string which matches the input data string. If the matching data string is found within the history buffer, the next step includes encoding the longest matching data string found by appending to the encoded data stream a tag indicating the longest matching data string was found and a string substitution code.
    Type: Grant
    Filed: November 27, 1990
    Date of Patent: September 8, 1992
    Assignee: Stac, Inc.
    Inventors: Douglas L. Whiting, Glen A. George, Glen E. Ivey
  • Patent number: 5126739
    Abstract: An apparatus and method as disclosed for converting an input data character stream into a variable length encoded data stream in a data compression system. The data compression system includes a history array means. The history array means has a plurality of entries and each entry of the history array means is for storing a portion of the input data stream. The method for converting the input data character stream includes the following steps. Performing a search in a history array means for the longest data string which matches the input data string. If the matching data string is found within the history buffer means, the next step includes encoding the longest matching data string found by appending to the encoded data stream a tag indicating the longest matching data string was found and a string substitution code.
    Type: Grant
    Filed: November 27, 1990
    Date of Patent: June 30, 1992
    Assignee: STAC Electronics
    Inventors: Douglas L. Whiting, Glen A. George, Glen E. Ivey
  • Patent number: 5016009
    Abstract: An apparatus and method for converting an input data character stream into a variable length encoded data stream in a data compression system. The data compression system includes a history array means. The history array means has a plurality of entries and each entry of the history array means is for storing a portion of the input data stream. The method for converting the input data character stream includes the following steps. Performing a search in a history array means for the longest data string which matches the input data string. If the matching data string is found within the history buffer means, the next step includes encoding the longest matching data string found by appending to the encoded data stream a tag indicating the longest matching data string was found and a string substitution code.
    Type: Grant
    Filed: January 13, 1989
    Date of Patent: May 14, 1991
    Assignee: Stac, Inc.
    Inventors: Douglas L. Whiting, Glen A. George, Glen E. Ivey
  • Patent number: 5003307
    Abstract: An apparatus and method are disclosed for converting an input data character stream into a variable length encoded data stream in a data compression system. The data compression system includes a shift register means. The shift register means has a plurality of entries and each entry of the shift register means is for storing a data character of the input data stream. The method for converting the input data character stream includes the following steps. Performing a search in the shift register means for a data string which matches the input data string. The step for performing the search includes the steps of broadcasting each input data character of the input data stream to each entry of the shift register means and comparing each input data character simultaneously with the previously stored contents of each entry of said shift register means.
    Type: Grant
    Filed: October 6, 1989
    Date of Patent: March 26, 1991
    Assignee: Stac, Inc.
    Inventors: Douglas L. Whiting, Glen A. George
  • Patent number: 4996690
    Abstract: An apparatus and/or method for generating parity digits of digital information (data) in a digital communication system is disclosed. The communication system (8) is for transferring a plurality of data intervals from an originating data source (12) to a data sink (13). Each data interval comprises one or more blocks of data and each block contains one or more bytes of data. The communication system (8) includes a temporary storage means (24) for holding the data for a limited period. Included are means for transferring (14, 40) one or more data intervals from the data source (12) to the temporary storage means (24) and means for transferring (22, 40) one of the data intervals from the temporary storage means (24) to the data sink (13) including means for calculating (72) error correcting code words associated with each data interval and means for storing (16) the error correcting code words for further processing.
    Type: Grant
    Filed: August 26, 1988
    Date of Patent: February 26, 1991
    Assignee: STAC Electronics
    Inventors: Glen A. George, Douglas L. Whiting
  • Patent number: 4930142
    Abstract: An apparatus and/or method for generating a digital clock signal which is frequency and phase referenced to an external digital data signal is disclosed. The external digital data signal is typically subject to variations in data frequency and high frequency jitter unrelated to changes in the data frequency.
    Type: Grant
    Filed: December 6, 1988
    Date of Patent: May 29, 1990
    Assignee: STAC, Inc.
    Inventors: Douglas L. Whiting, Glen A. George