The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 08, 1998
Filed:
Apr. 02, 1996
Henrique S Malvar, Andover, MA (US);
Gary J Sullivan, Arlington, MA (US);
Gregory W Wornell, Wellesley, MA (US);
PictureTel Corporation, Andover, MA (US);
Abstract
A method and apparatus for encoding a sampled signal using a nonscalar vector quantizer. A lapping window operator is applied to blocks of signal samples of length greater than N to produce length-N transform vectors which are then encoded by a nonscalar vector quantizer. The method and apparatus may use or have a window operator that is identical to that of the modulated lapped transform, that is a 2N.times.N matrix operator, that is identical to that of the modulated lapped transform with asymmetrical, orthogonal butterflies, or that has butterfly transmittances given by h�n!=sin�(2n+1).pi./4N!. The method and apparatus may use or have a vector quantizer is an unconstrained mean-square optimized vector quantizer having codewords of length N. The method and apparatus may use or have a vector reconstructor being an inverse of the nonscalar vector quantizer to reconstruct length-N vectors coupled through a transmission channel to received the length-N vectors from the vector quantizer, and a block decoder connected to receive as input the reconstructed length-N vectors from the vector reconstructor and to apply a reconstructor window operator to produce vectors that may be superimposed to generate a reconstruction of the sampled signal. The reconstructor window operator may be the inverse of the lapping window operator.