Patent ID: 6697782
Filing Date: 2004-02-24
Classification: G10L

Abstract:
A method for recognizing speech commands, in which a group of command words selectable by speech commands are defined, a time window is defined, within which the recognition of the speech command is performed, and a first recognition stage is performed, in which the recognition result of the first recognition stage is selected, characterized in that further in the method:a first confidence value is determined for the recognition result of the first recognition stage, a first threshold value (Y) is determined, said first confidence value is compared with said first threshold value (Y), if said first confidence value is greater than or equal to said first threshold value (Y), the recognition result of the first recognition stage is selected as the recognition result of the speech command, if said first confidence value is smaller than said first threshold value (Y), a second recognition stage is performed for the speech command, wherein said time window is extended, and a second confidence value is determined for the recognition result of the second recognition stage, said second confidence value is compared with said threshold value (Y), if said second confidence value is greater than or equal to said first threshold value (Y), the command word selected at the second stage is selected as the recognition result for the speech command, if said second confidence value is smaller than said first threshold value (Y), a comparison stage is performed, wherein feature vectors obtained from the first and second recognition stages are compared to each other to determine a probability that they are substantially the same, wherein if the probability exceeds a predetermined value, the command word selected at the second stage is selected as the recognition result for the speech command.