Fast waveform synchronization for concentration and time-scale modification of speech

• US 20020143526A1
• Filed: 09/14/2001
• Published: 10/03/2002
• Est. Priority Date: 09/15/2000
• Status: Active Grant

• Current Assignee: Cerence Operating Company (Cerence Inc.)
• Original Assignee: Lernout & Hauspie Speech Products NV (Intel Corporation)
• Inventors: Coorman, Geert, Coile, Bert Van
• Granted Patent: US 7,058,569 B2
• Time in Patent Office: Days
• US Class Current: 704/211
• CPC Class Codes: G10L 13/07 Concatenation rules
• CPC Class Codes: G10L 21/04 Time compression or expansion

Abstract

A synthesis method for concatenative speech synthesis is provided for efficiently concatenating waveform segments in the time-domain. A digital waveform provider produces an input sequence of digital waveform segments. A waveform concatenator concatenates the input segments by using waveform blending within a concatenation zone to synchronize, weight, and overlap-add selected portions of the input segments to produce a single digital waveform. The synchronizing includes determining a minimum weighted energy anchor in the selected portion of each input segment and aligning synchronization peaks in a local vicinity of each anchor.

Claims

1. A digital waveform concatenation system for use in an acoustic processing application, the system comprising:

a digital waveform provider that produces an input sequence of at least two digital waveform segments, each waveform segment being a sequence of samples; and

a waveform concatenator that synchronizes, weights, and overlap-adds selected portions of the input segments to concatenate the input segments by using waveform blending within a concatenation zone to produce a single digital waveform;

wherein the synchronizing includes aligning minimum energy anchors in each input segment, each minimum energy anchor location being optimized based on determining minimum weighted energy in the selected portion.

2. A concatenation system according to claim 1, wherein the acoustic processing application includes a text-to-speech application.

3. A concatenation system according to claim 1, wherein the acoustic processing application includes a speech broadcast application.

4. A concatenation system according to claim 1, wherein the acoustic processing application includes a carrier-slot application.

5. A concatenation system according to claim 1, wherein the acoustic processing application includes a time-scale modification system.

6. A concatenation system according to claim 1, wherein the waveform segments include at least one of speech diphones and speech triphones.

7. A concatenation system according to claim 1, wherein the waveform segments include at least one of speech phones and speech demi-phones.

8. A concatenation system according to claim 1, wherein the waveform segments include at least one of speech demi-syllables, speech syllables, words, and phrases.

9. A concatenation system according to claim 1, wherein determining minimum weighted energy in the selected portion includes using a sliding weighted energy calculation algorithm.

10. A concatenation system according to claim 1, wherein the input segments are filtered before synchronizing.

11. A concatenation system according to claim 1, wherein aligning minimum energy anchors includes determining a largest waveform peak or trough in the close neighborhood of each minimum energy anchor.

12. A concatenation system according to claim 11, wherein the close neighborhood is an interval of at least one pitch period containing the minimum energy anchor.

13. A concatenation system according to claim 11, wherein the close neighborhood is the selected portion of the input segment.

14. A concatenation system according to claim 11, wherein the location of one minimum energy anchor is the lowest weighted energy location in the selected portion.

15. A concatenation system according to claim 14, wherein another minimum energy anchor location is chosen such that the previously determined waveform peak or trough in each selected portion coincide when the input segments are overlap-added.

17. A concatenation system according to claim 16, wherein the acoustic processing application includes a text-to-speech application.

18. A concatenation system according to claim 16, wherein the acoustic processing application includes a speech broadcast application.

19. A concatenation system according to claim 16, wherein the acoustic processing application includes a carrier-slot application.

20. A concatenation system according to claim 16, wherein the waveform segments include at least one of speech diphones and speech triphones.

21. A concatenation system according to claim 16, wherein the waveform segments include at least one of speech phones and speech demi-phones.

22. A concatenation system according to claim 16, wherein the waveform segments include at least one of speech demi-syllables, speech syllables, words, and phrases.

23. A concatenation system according to claim 16, wherein the input segments are filtered before aligning.

25. A concatenation system according to claim 24, wherein the acoustic processing application includes a text-to-speech application.

26. A concatenation system according to claim 24, wherein the acoustic processing application includes a speech broadcast application.

27. A concatenation system according to claim 24, wherein the acoustic processing application includes a carrier-slot application.

28. A concatenation system according to claim 24, wherein the acoustic processing application includes a time-scale modification system.

29. A concatenation system according to claim 24, wherein the waveform segments include at least one of speech diphones and speech triphones.

30. A concatenation system according to claim 24, wherein the waveform segments include at least one of speech phones and speech demi-phones.

31. A concatenation system according to claim 24, wherein the waveform segments include at least one of speech demi-syllables, speech syllables, words, and phrases.

32. A concatenation system according to claim 24, wherein determining a minimum weighted energy anchor includes using a sliding weighted energy calculation algorithm.

33. A concatenation system according to claim 24, wherein the input segments are filtered before synchronizing.

34. A concatenation system according to claim 24, wherein aligning synchronization peaks or troughs includes determining a largest waveform peak or trough in the close neighborhood of each anchor.

35. A concatenation system according to claim 34, wherein the close neighborhood is an interval of at least one pitch period containing the minimum energy anchor.

36. A concatenation system according to claim 34, wherein the close neighborhood is the selected portion of the input segment.

37. A concatenation system according to claim 34, wherein the location of one anchor is chosen such that the synchronization peaks or troughs in each selected portion coincide when the input segments are overlap-added.

39. A concatenation system according to claim 38, wherein the acoustic processing application includes a text-to-speech application.

40. A concatenation system according to claim 38, wherein the acoustic processing application includes a speech broadcast application.

41. A concatenation system according to claim 38, wherein the acoustic processing application includes a carrier-slot application.

42. A concatenation system according to claim 38, wherein the acoustic processing application includes a time-scale modification system.

43. A concatenation system according to claim 38, wherein the waveform segments include at least one of speech diphones and speech triphones.

44. A concatenation system according to claim 38, wherein the waveform segments include at least one of speech phones and speech demi-phones.

45. A concatenation system according to claim 38, wherein the waveform segments include at least one of speech demi-syllables, speech syllables, words, and phrases.

46. A concatenation system according to claim 38, wherein determining a minimum weighted energy anchor includes using a sliding weighted energy calculation algorithm.

47. A concatenation system according to claim 38, wherein the input segments are filtered before synchronizing.

48. A concatenation system according to claim 38, wherein aligning synchronization peaks or troughs includes determining a largest waveform peak or trough in the close neighborhood of the anchor and determining a corresponding peak or trough in the selected portion of the other input segment.

49. A concatenation system according to claim 48, wherein the close neighborhood is an interval of at least one pitch period containing the minimum weighted energy anchor.

50. A concatenation system according to claim 48, wherein the close neighborhood is the selected portion of the input segment.

16. A digital waveform concatenation system for use in an acoustic processing application, the system comprising:

a digital waveform provider that produces an input sequence of at least two digital waveform segments, each waveform segment being a sequence of samples; and

a waveform concatenator that synchronizes, weights, and overlap-adds selected portions of the input segments to concatenate the input segments by using waveform blending within a concatenation zone to produce a single digital waveform;

wherein the synchronizing includes aligning a largest waveform peak or trough in the selected portion of each input segment.

24. A digital waveform concatenation system for use in an acoustic processing application, the system comprising:

a digital waveform provider that produces an input sequence of at least two digital waveform segments, each waveform segment being a sequence of samples; and

a waveform concatenator that synchronizes, weights, and overlap-adds selected portions of the input segments to concatenate the input segments by using waveform blending within a concatenation zone to produce a single digital waveform;

wherein the synchronizing includes determining a minimum weighted energy anchor in the selected portion of each input segment and aligning synchronization peaks or troughs in a local vicinity of each anchor.

38. A digital waveform concatenation system for use in an acoustic processing application, the system comprising:

a digital waveform provider that produces an input sequence of at least two digital waveform segments, each waveform segment being a sequence of samples; and

a waveform concatenator that synchronizes, weights, and overlap-adds selected portions of the input segments to concatenate the input segments by using waveform blending within a concatenation zone to produce a single digital waveform;

wherein the synchronizing includes determining a minimum weighted energy anchor in the selected portion of one input segment and aligning synchronization peaks or troughs in each selected portion.