Implementing SpeechĆ
Recognition Algorithms on the
TMS320C2xx Platform
Application
Report
1998 Digital Signal Processing Solutions
Printed in U.S.A., April 1998 SPRA178
Implementing Speech-Recognition
Algorithms on the TMS320C2xx Platform
Lim Hong Swee
Texas Instruments Singapore (P&E) Ltd.
SPRA178
April 1998
Printed on Recycled Paper
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Implementing Speech-Recognition Algorithms on the TMS320C2xx Platform
Contents
1 Speech-Recognition Algorithm 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.1 The Acoustic Front End 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 Search Algorithm 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 Fixed Point Implementation of a min_HMM 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1 Dynamic-Range Determination 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Q-point Setting 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3 Utterance Detection 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3 Real-Time Software Implementation 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4 Conclusion 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
References 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
