Synthesis of speech using regenerated phase information

Details Synthesis of speech using regenerated phase information Synthesis of speech using regenerated phase information

G - Physics

10

L

G10L 13/04 (2006.01) G10L 11/06 (2006.01) G10L 19/02 (2006.01) G10L 19/06 (2006.01)

Patent

CA 2169822

The spectral magnitude and phase representation used in Multi-Band Excitation (MBE) based speech coding systems is improved. At the encoder the digital speech signal is divided into frames, and a fundamental frequency, voicing information, and a set of spectral magnitudes are estimated for each frame. A spectral magnitude is computed at each harmonic frequency (ie. multiples of the estimated fundamental frequency) using a new estimation method which is independent of voicing state and which corrects for any offset between the harmonic and the frequency sampling grid. The result is a fast, FFT compatible method which produces a smooth set of spectral magnitudes without the sharp discontinuities introduced by voicing transitions as found in prior MBE based speech coders. Quantization efficiency is thereby improved, producing higher speech quality at lower bit rates. In addition, smoothing methods, typically used to reduce the effect of bit errors or to enhance formants, are more effective since they are not confused by false edges (i.e. discontinuities) at voicing transitions. Overall speech quality and intelligibility are improved. At the decoder a bit stream is received and then used to reconstruct a fundamental frequency, voicing information, and a set of spectral magnitudes for a sequence of frames. The voicing information is used to label each harmonic as either voiced or unvoiced, and for voiced harmonics an individual phase is regenerated as a function of the spectral magnitudes localized about that harmonic frequency. The decoder then synthesizes the voiced and unvoiced component and adds them to produce the synthesized speech. The regenerated phase more closely approximates actual speech in terms of peak-to-rms value relative to the prior art, thereby yielding improved dynamic range. In addition the synthesized speech is perceived as more natural and exhibits fewer phase related distortions.

Affiliated with

Also associated with

Rating

Synthesis of speech using regenerated phase information does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Synthesis of speech using regenerated phase information, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Synthesis of speech using regenerated phase information will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFCA-PAI-O-1810235