Key word and key phrase based speech recognizer for information retrieval systems

• US 20030204399A1
• Filed: 04/25/2002
• Published: 10/30/2003
• Est. Priority Date: 04/25/2002
• Status: Abandoned Application

• Current Assignee: Mitsubishi Electric Research Laboratories, Inc. (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Electric Research Laboratories, Inc. (Mitsubishi Electric Corporation)
• Inventors: Ramakrishnan, Bhiksha, Wolf, Peter P., McDonald, David D.
• Application Number:
  US10/132,550
• Publication Number:
  US 20030204399A1
• Time in Patent Office: Days
• US Class Current: 704/251
• CPC Class Codes: G10L 15/06 Creation of reference templates; Training of speech recognition systems, e.g. adaptation to the characteristics of the speaker's voice G10L15/14 takes precedence
• CPC Class Codes: G10L 2015/0631 Creating reference templates; Clustering

Abstract

A method for constructing a dynamic vocabulary for a speech recognizer used with a database of indexed documents. Key words are first extracted from each of the documents in the database as the documents are indexed. The extracted key words are than used to dynamically construct the vocabulary of the speech recognizer or a search engine.

Claims

1. A method for constructing a dynamic vocabulary for a speech recognizer used with a database of indexed documents, comprising:

indexing each of a plurality of documents in the database;

extracting key words from each indexed document; and

storing the key words as entries in the vocabulary of the speech recognizer.

2. The method of claim 1 wherein the key words are in a sequence to form a key phrase.

3. The method of claim 1 wherein the key words are tagged in the indexed documents.

4. The method of claim 1 further comprising:

stemming the extracted key words.

5. The method of claim 1 further comprising:

forming a weighted list of all words in each document, wherein the weight of each word is equal to a frequency of appearance of the word in the document, and the key words have frequencies greater than a predetermined threshold.

6. The method of claim 2 wherein the key phrase is stored in the vocabulary as valid path of a grammar based on all of the entries in the vocabulary.

7. The method of claim 1 further comprising:

representing the key words as a lattice, the lattice representing likely possible sequential combinations of the key words.

8. The method of claim 7 wherein the lattice is forwarded to a search engine for searching the database of indexed documents.

9. The method of claim 7 wherein the key words are represented in the lattice by phonemes.

10. The method of claim 1 wherein the keywords are included in a vocabulary of a search engine.