US5596675A
Expired / Lapsed
US
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Method and apparatus for speech encoding, speech decoding, and speech post processing
Assignee: Mitsubishi Electric Corp
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Filing: 1995-09-13
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Granted: 1997-01-21
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Expires: 2015-09-13
Abstract
Abstract A speech analysis unit and a window locating means are implemented in a speech coding apparatus. The speech coding apparatus encodes input speech per analysis frame defined having a fixed length and is offset at fixed interval. The speech analysis unit extracts frequency spectrum characteristic parameters of the input speech taken within an analysis window. The location of the analysis window is specified by the window locating means. The window locating unit selects the location of the analysis window which is used in extracting the frequency spectrum characteristic parameters at the speech analysis unit. In this case, depending upon the characteristic parameter of the input speech within and near the frame concerned, the window locating unit selects the location of the analysis window within the range which is not to be exceeding the range of the frame concerned.
Inventors
- 👤 Jun Ishii
- 👤 Shinya Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:46
CPC Classifications
G; G10; G10L; G10L19/00; G10L19/04; G10L19/06; G10L19/002; G10L19/02; G10L19/0212; G10L19/16; G10L19/18; G10L19/24; G10L19/26
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
139 words
A speech coding apparatus for coding an input speech signal within an analysis window of an analysis frame, comprising: (a) window locating means for defining a plurality of analysis windows at different locations in the analysis frame, the window locating means including means for receiving a segment of the input speech signal within each of the analysis windows, means for calculating a predefined feature of the segment of the input speech signal within each analysis window, means for comparing the calculated features of each analysis window, and means for selecting an analysis window based on a result of the comparison; (b) speech analysis means for extracting characteristic parameters of the input speech signal in the selected analysis window selected by the window locating means; and (c) coding means for receiving the characteristic parameters and for encoding the characteristic parameters.
Claim 2
Dependent Claim
139 words
A speech coding apparatus for coding an input speech signal within an analysis window of an analysis frame, comprising: (a) window locating means for defining a plurality of analysis windows at different locations in the analysis frame, the window locating means including means for receiving a segment of the input speech signal within each of the analysis windows, means for calculating a predefined feature of the segment of the input speech signal within each analysis window, means for comparing the calculated features of each analysis window, and means for selecting an analysis window based on a result of the comparison; (b) speech analysis means for extracting characteristic parameters of the input speech signal in the selected analysis window selected by the window locating means; and (c) coding means for receiving the characteristic parameters and for encoding the characteristic parameters.
Claim 3
Dependent Claim
33 words
The speech coding apparatus of claim 1, wherein the predefined feature is a power of the input speech signal, and wherein an analysis window having a maximum power value is the window selected.
Claim 4
Dependent Claim
57 words
The speech coding apparatus of claim 1 or 2, wherein the speech analysis means comprises: means for providing a second analysis window different from the selected analysis window: and means for calculating a value of power of the input speech signal within the second analysis window and for outputting the calculated power value to the coding means.
Claim 5
Dependent Claim
24 words
The speech coding apparatus of claim 3, wherein a center of the second analysis window is placed at a center of the analysis frame.
Claim 6
Dependent Claim
35 words
The speech coding apparatus of claim 3, wherein the analysis frame has a fixed frame length and the second analysis window has a window length which is substantially the same as the analysis frame length.
Claim 7
Dependent Claim
28 words
The speech coding apparatus of claim 1, wherein the selected analysis window is the window having a center which is substantially in the center of the analysis frame.
Claim 8
Dependent Claim
32 words
The speech coding apparatus of claim 1, wherein the analysis frame has a fixed length and the analysis window has a window length which is substantially the same as the frame length.
Claim 9
Dependent Claim
37 words
The speech coding apparatus of claim 1, wherein the predefined feature is a spectrum of the input speech signal of each analysis window and wherein the comparison is a comparison of the spectrums of each analysis window.
Claim 10
Dependent Claim
40 words
The speech coding apparatus of claim 1, wherein the predefined feature is an auto correlation of the input speech signal within each analysis window and wherein an analysis window having an auto correlation function having periodicity is the window selected.
Claim 11
Dependent Claim
104 words
A speech coding method for encoding input speech within a selected analysis window of an analysis frame, comprising the steps of: (a) creating an analysis window having a location in the analysis frame; (b) calculating a value of power of a segment of the input speech signal within the analysis window; (c) repeating the above steps, such that a plurality of analysis windows are created at a plurality of different locations within the analysis frame; (d) comparing the power values of each of the plurality of analysis windows and selecting an analysis window of the plurality of analysis windows having a maximum power value.
Claim 12
Dependent Claim
104 words
A speech coding method for encoding input speech within a selected analysis window of an analysis frame, comprising the steps of: (a) creating an analysis window having a location in the analysis frame; (b) calculating a value of power of a segment of the input speech signal within the analysis window; (c) repeating the above steps, such that a plurality of analysis windows are created at a plurality of different locations within the analysis frame; (d) comparing the power values of each of the plurality of analysis windows and selecting an analysis window of the plurality of analysis windows having a maximum power value.
Claim 13
Dependent Claim
58 words
The speech coding method of claim 10, further comprising the steps of: (a) extracting characteristic parameters of the input speech signal within the selected analysis window; (b) creating a second analysis window and calculating a value of power of the input speech within the second analysis window; and (c) encoding the extracted characteristic parameters and the calculated power.
Claim 14
Dependent Claim
35 words
The speech coding method of claim 11, wherein the step of creating a second analysis window includes a step of positioning a center of the second analysis window at a center of the analysis frame.
Claim 15
Dependent Claim
38 words
The speech coding method of claim 12, wherein the step of creating a second analysis window includes a step of setting a length of the second analysis window substantially the same as a length of the analysis frame.
Claim 16
Dependent Claim
102 words
A speech coding method for coding an input speech signal comprising the steps of: receiving a segment of the input speech signal corresponding to an analysis frame of the input speech signal: creating a plurality of analysis windows at different locations within the analysis frame; for each one of the plurality of analysis windows, calculating a value of power of the input signal contained within the one of the plurality of analysis windows; comparing the value of power of each of the plurality of analysis windows; selecting an analysis window of the plurality of analysis windows having a greatest value of power.
Claim 17
Dependent Claim
102 words
A speech coding method for coding an input speech signal comprising the steps of: receiving a segment of the input speech signal corresponding to an analysis frame of the input speech signal: creating a plurality of analysis windows at different locations within the analysis frame; for each one of the plurality of analysis windows, calculating a value of power of the input signal contained within the one of the plurality of analysis windows; comparing the value of power of each of the plurality of analysis windows; selecting an analysis window of the plurality of analysis windows having a greatest value of power.
Claim 18
Dependent Claim
25 words
The speech coding method of claim 14, further comprising the steps of: extracting characteristic parameters of the input speech signal within the selected analysis window.
Claim 19
Dependent Claim
47 words
The speech coding method of claim 14 further comprising the steps of: creating a second analysis window within the analysis frame, wherein the second analysis window has a center substantially in the center of the analysis frame; and encoding the extracted characteristic parameters and the calculated power.
References Cited (Backward Citations)
US4885790A
Cited
US5327518A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2000-01-21 | 2000-07-22 | 2001-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-01-21 | 2004-07-22 | 2005-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-01-21 | 2008-07-22 | 2009-01-21 | $7700.00 | Window Closed / Lapsed |