Electrical audio signal processing systems and devices – Monitoring/measuring of audio devices – Loudspeaker operation
Patent
1983-10-21
1987-10-20
Shaw, Gareth D.
Electrical audio signal processing systems and devices
Monitoring/measuring of audio devices
Loudspeaker operation
G10L 100
Patent
active
047019557
ABSTRACT:
A variable frame length vocoder extracts a feature vector for each given frame, a predetermined number of frames being defined as a section. The feature vectors in each section are stored, changes in feature vectors within a section being approximated by a given number of variable time length flat sections with a constant time length portion between adjacent flat sections, adjacent flat sections being interconnected by an inclined section of the constant time length duration. A feature vector of each flat section is outputted as a representative vector of the flat section, and the number of frames comprising the flat section is outputted as a repeat signal. This information is processed at the synthesis side of the vocoder to produce the feature vector in each inclined section by interpolating the representative vectors of the flat sections on both sides of the inclined section.
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Mills John G.
NEC Corporation
Shaw Gareth D.
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