Apparatus and method for normalizing an input speech signal
First Claim
1. An apparatus for normalising an input speech signal, the apparatus comprising:
- dividing means arranged to divide the input speech signal into a succession of frames;
level determining means arranged to determine a level of the input speech signal during each said frame;
normalising means arranged to normalise the level of the speech signal in each frame;
detection means arranged to detect a voiced signal in the input speech signal; and
control means arranged to adjust said normalising means when said detection means detects a voiced signal.
0 Assignments
0 Petitions
Accused Products
Abstract
In an apparatus for extracting information from an input speech signal, a preprocessor, a buffer, a segmenter, an acoustic classifier and a feature extractor are provided. The preprocessor generates formant related information for consecutive time frames of the input speech signal. This formant related information is fed into the buffer, which can store signals representative of a plurality of frames. The segmenter monitors the signals representative of the incoming frames and identifies segments in the input speech signal during which variations in the formant related information remain within prespecified limits. The acoustic classifier then determines classification information for each segment identified by the segmenter, based on acoustic classes found in training data. The feature estimator then determines, for each segment, the information required, based on the input speech signal during that segment, training data and the classification information determined by the acoustic classifier.
-
Citations
11 Claims
-
1. An apparatus for normalising an input speech signal, the apparatus comprising:
-
dividing means arranged to divide the input speech signal into a succession of frames;
level determining means arranged to determine a level of the input speech signal during each said frame;
normalising means arranged to normalise the level of the speech signal in each frame;
detection means arranged to detect a voiced signal in the input speech signal; and
control means arranged to adjust said normalising means when said detection means detects a voiced signal. - View Dependent Claims (2, 3, 4, 5)
-
-
5. An apparatus according to claim 4, wherein the values gi, gi−
- 1 and M in the equation are logarithmically scaled values.
-
6. A method for normalising an input speech signal, the method comprising:
-
the step of dividing the input speech signal into a succession of frames;
the step of determining a level of the input speech signal during each said frame;
the step of normalising the level of the speech signal in each frame;
the step of detecting a voiced signal in the input speech signal;
the step of adjusting said step of normalising when said detecting step detects a voiced signal in the input speech signal. - View Dependent Claims (7, 8, 9, 10)
-
-
10. A method according to claim 9, wherein the values gi, gi−
- 1 and M in the equation are logarithmically scaled values.
-
11. An apparatus for normalising an input speech signal, the apparatus comprising:
-
dividing means for dividing the input speech signal into a succession of frames;
level determining means for determining a level of the input speech signal during each of said frames;
normalising means for normalising the level of the speech signal in each frame using a normalisation factor;
detection means for detecting a portion of the input speech signal having periodic characteristics indicative of a vocalized sound; and
control means for adjusting said normalisation factor using the speech signal within the detected portion.
-
Specification