The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 09, 2008
Filed:
Aug. 18, 2004
Sadaoki Furui, Tokyo, JP;
Zhipeng Zhang, Tokyo, JP;
Tsutomu Horikoshi, Kamakura, JP;
Toshiaki Sugimura, Yokohama, JP;
Sadaoki Furui, Tokyo, JP;
Zhipeng Zhang, Tokyo, JP;
Tsutomu Horikoshi, Kamakura, JP;
Toshiaki Sugimura, Yokohama, JP;
Sadaoki Furui and NTT DoCoMo, Inc., Tokyo, JP;
Abstract
An object of the present invention is to facilitate dealing with noisy speech with varying SNR and save calculation costs by generating a speech model with a single-tree-structure and using the model for speech recognition. Every piece of noise data stored in a noise database is used under every SNR condition to calculate the distance between all noise models with the SNR conditions and the noise-added speech is clustered. Based on the result of the clustering, a single-tree-structure model space into which the noise and SNR are integrated is generated (steps Sto S). At a noise extraction step (step S), inputted noisy speech to be recognized is analyzed to extract a feature parameter string and the likelihoods of HMMs are compared one another to select an optimum model from the tree-structure noisy speech model space (step S). Linear transformation is applied to the selected noisy speech model space so that the likelihood is maximized (step S).