Signal conditioned minimum error rate training for continuous speech recognition
First Claim
Patent Images
1. A method of signal conditioning for removing an unknown signal bias in a speech signal in a speech recognition system storing a set of recognition models, comprising the following steps:
- (A) generating a feature signal which characterizes features of the speech signal, the feature signal comprising one or more frames of feature vectors;
(B) storing the feature signal in memory;
(C) constructing a codebook comprising one or more clusters based on the set of recognition models;
(D) calculating a cluster-specific bias for each of the clusters of the codebook;
(E) calculating a cluster-specific weight for each of the clusters of the codebook;
(F) generating a frame-dependent weighted bias signal for each frame of the feature signal;
(G) subtracting the frame-dependent weighted bias signal for each frame of the feature signal from each frame of the feature signal to generate a conditioned feature signal; and
(H) storing the conditioned feature signal in memory to replace the feature signal.
4 Assignments
0 Petitions
Accused Products
Abstract
Hierarchical signal bias removal (HSBR) signal conditioning uses a codebook constructed from the set of recognition models and is updated as the recognition models are modified during recognition model training. As a result, HSBR signal conditioning and recognition model training are based on the same set of recognition model parameters, which provides significant reduction in recognition error rate for the speech recognition system.
-
Citations
7 Claims
-
1. A method of signal conditioning for removing an unknown signal bias in a speech signal in a speech recognition system storing a set of recognition models, comprising the following steps:
-
(A) generating a feature signal which characterizes features of the speech signal, the feature signal comprising one or more frames of feature vectors; (B) storing the feature signal in memory; (C) constructing a codebook comprising one or more clusters based on the set of recognition models; (D) calculating a cluster-specific bias for each of the clusters of the codebook; (E) calculating a cluster-specific weight for each of the clusters of the codebook; (F) generating a frame-dependent weighted bias signal for each frame of the feature signal; (G) subtracting the frame-dependent weighted bias signal for each frame of the feature signal from each frame of the feature signal to generate a conditioned feature signal; and (H) storing the conditioned feature signal in memory to replace the feature signal. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
Specification