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:
Jun. 28, 2016
Filed:
Mar. 12, 2013
Amazon Technologies, Inc., Reno, NV (US);
Stan Weidner Salvador, Tega Cay, SC (US);
Amazon Technologies, Inc., Seattle, WA (US);
Abstract
Features are disclosed for applying maximum likelihood methods to channel normalization in automatic speech recognition ('ASR'). Feature vectors computed from an audio input of a user utterance can be compared to a Gaussian mixture model. The Gaussian that corresponds to each feature vector can be determined, and statistics (e.g., constrained maximum likelihood linear regression statistics) can then be accumulated for each feature vector. Using these statistics, or some subset thereof, offsets and/or a diagonal transform matrix can be computed for each feature vector. The offsets and/or diagonal transform matrix can be applied to the corresponding feature vector to generate a feature vector normalized based on maximum likelihood methods. The ASR process can then proceed using the transformed feature vectors.