1. Speech Processing Dec. 11, 2006 YOUNG-CHAN LEE
Spectrum Enhancement
Speech Processing
Dec. 11, 2006
YOUNG-CHAN LEE

2. Spectrum enhancement Goal : find noiseless spectrum for speech signal
Regard corrupted signal consist of noise, pure signal and background noise.
Same spectrum components

3. Equation-method(1) Spectrum enhancement Global information (average)
Local information (average)
Estimate of background

4. Spectrogram

5. New Equation – method-(2)
Analysis of each component and find parameters
Part – 1 (Global energy)
Part – 2 (local energy)
Part – 3 (Background estimate)
Part – 4 (Floor)

6. Additive Noise Suppression
Suppress noise compare to speech signal

7. Part - 1
Spectrum and global
energy

8. Part - 2
Spectrum and local
energy

9. Part - 3
Spectrum and background estimate

10. Estimate of Background
Before background estimate
New background estimate

11. Part - 4
Spectrum and floor

12. Overall spectrum

13. Comparison of enhanced spectrum

14. File list (used same parameters)
Examples
File list (used same parameters)
CCW170007_000.ulaw
CCW170007_001.ulaw
CCW170007_002.ulaw
CCW170007_003.ulaw
CCW170007_004.ulaw
CCW170007_005.ulaw
CCW170007_006.ulaw
CCW170007_007.ulaw
CCW170007_008.ulaw
CCW170007_009.ulaw

15. Example1 (CCW _000.ulaw)

16. Continue (spectrum)

17. Example2 (CCW _001.ulaw)

18. Continue (spectrum)

19. Example3 (CCW _002.ulaw)

20. Continue (spectrum)

21. Example4 (CCW _003.ulaw)

22. Continue (spectrum)

23. Example5 (CCW _004.ulaw)

24. Continue (spectrum)

25. Example6 (CCW _005.ulaw)

26. Continue (spectrum)

27. Example7 (CCW _006.ulaw)

28. Continue (spectrum)

29. Example8 (CCW _007.ulaw)

30. Continue (spectrum)

31. Example9 (CCW _008.ulaw)

32. Continue (spectrum)

33. Example10 (CCW _009.ulaw)

34. Continue (spectrum)

35. Conclusions
Global energy, local energy, background estimate greatly affected to build enhanced spectrum.
Part3 and part4 showed good spectrum estimation.
In new method, we don’t need to change parameter values according to input files.

36. MATLAB Demo

37. Thank you!
Merry Christmas