Patents by Inventor Sigeyuki Unagami

Sigeyuki Unagami 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).

  • Vector quantization encoder and vector quantization decoder
    Patent number: 5151968
    Abstract: An apparatus for compressing and decompressing speech signals. The encoder or decoder comprises a plurality of codebooks each controlling a plurality of indexed code vectors for a different frequency band. Each of the codebooks is provided with a synthesis filter for reproducing a signal wave shape based on a code vector provided by the corresponding codebook. The encoder or decoder further comprises an adder for computing a sum of signal wave shapes reproduced by the synthesis filters. This arrangement can reduce the memory size of each codebook used for an encoding or a decoding process and an amount of operations of the encoding or decoding process.
    Type: Grant
    Filed: August 3, 1990
    Date of Patent: September 29, 1992
    Assignee: Fujitsu Limited
    Inventors: Yoshinori Tanaka, Tomohiko Taniguchi, Fumio Amano, Yasuji Ohta, Sigeyuki Unagami