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A comparison of orthogonal transformations for digital speech processing.Discrete forms of the Fourier, Hadamard, and Karhunen-Loeve transforms are examined for their capacity to reduce the bit rate necessary to transmit speech signals. To rate their effectiveness in accomplishing this goal the quantizing error (or noise) resulting for each transformation method at various bit rates is computed and compared with that for conventional companded PCM processing. Based on this comparison, it is found that Karhunen-Loeve provides a reduction in bit rate of 13.5 kbits/s, Fourier 10 kbits/s, and Hadamard 7.5 kbits/s as compared with the bit rate required for companded PCM. These bit-rate reductions are shown to be somewhat independent of the transmission bit rate.
Document ID
19720033739
Document Type
Reprint (Version printed in journal)
Authors
Campanella, S. J.
Robinson, G. S. (COMSAT Laboratories Clarksburg, Md., United States)
Date Acquired
August 6, 2013
Publication Date
December 1, 1971
Publication Information
Publication: IEEE Transactions on Communication Technology
Volume: COM-19
Subject Category
COMMUNICATIONS
Distribution Limits
Public
Copyright
Other