Multi-pass echo residue detection with speech application intelligence

1. A method for detecting echo residue associated with a speech application, the method comprising:

filtering audio data to determine whether the audio data should be further analyzed;

correlating audio data from an input channel with audio data from an output channel to obtain a correlation result;

comparing a determined value of the correlation result with a predetermined threshold; and

categorizing the audio data for the input channel as including an acceptable level of residual echo when the determined value of the correlation result is greater than the predetermined threshold, and categorizing the audio data for the input channel as including an unacceptable level of residual echo when the determined value of the correlation result is less than the predetermined threshold,

wherein the filtering further comprises determining whether a duration of a user input is at least a predetermined duration, and when the user input is at least the predetermined duration, extracting the predetermined duration of the user input from a total duration of the user input for further analysis, and when the user input is not at least the predetermined duration, ending the analysis.

2. The method for detecting echo residue using speech application data of claim 1 ,

wherein the filtering further comprises comparing a root mean square of the user input with a predetermined maximum threshold, and categorizing the user input as containing more than a predetermined level of noise when the root mean square of the user input is not less than the predetermined threshold.

3. The method for detecting echo residue using speech application data of claim 1 ,

wherein the filtering further comprises comparing a root mean square of the user input with a predetermined minimum threshold, and categorizing the user input as containing less than a predetermined level of noise when the root mean square of the user input is not greater than the predetermined threshold.

4. The method for detecting echo residue using speech application data of claim 1 ,

wherein the filtering further comprises comparing a maximum amplitude of the user input with a predetermined threshold, and categorizing the user input as containing more than a predetermined level of noise when the maximum amplitude of the user input is not less than the predetermined threshold.

5. The method for detecting echo residue using speech application data of claim 1 ,

wherein the filtering further comprises determining whether the audio data contains user input.

6. The method for detecting echo residue using speech application data of claim 1 ,

wherein the correlated audio data is audio data having a level of noise within a predetermined range.

7. The method for detecting echo residue using speech application data of claim 1 , the correlating further comprising:

correlating user input from the input channel with a scripted audible prompt provided over the output channel.

8. The method for detecting echo residue using speech application data of claim 7 , the correlating further comprising:

correlating the predetermined duration of the user input with a predetermined duration of the scripted audible prompt, and classifying a correlation result according to a predetermined correlation threshold.

9. The method for detecting echo residue using speech application data of claim 1 , wherein the predetermined duration is approximately six seconds.

10. A tangible computer readable medium for storing a computer program that detects echo residue associated with a speech application, comprising:

a filtering code segment that filters audio data to determine whether the audio data should be further analyzed;

an audio data correlating code segment that correlates audio data from an input channel with audio data from an output channel to obtain a correlation result;

a comparing code segment that compares a determined value of the correlation result with a predetermined threshold; and

a categorizing code segment that categorizes the audio data for the input channel as including an acceptable level of residual echo when the determined value of the correlation result is greater than the predetermined threshold, and that categorizes the audio data for the input channel as including an unacceptable level of residual echo when the determined value of the correlation result is less than the predetermined threshold,

wherein the filtering code segment further comprises determining whether a duration of a user input is at least a predetermined duration, and when the user input is at least the predetermined duration, extracting the predetermined duration of the user input from a total duration of the user input for further analysis, and when the user input is not at least the predetermined duration, ending the analysis.

11. The computer readable medium of claim 10 ,

wherein the filtering code segment further compares a root mean square of the user input with a predetermined maximum threshold, and categorizes the user input as containing more than a predetermined level of noise when the root mean square of the user input is not less than the predetermined threshold.

12. The computer readable medium of claim 10 ,

wherein the filtering code segment further compares a root mean square of the user input with a predetermined minimum threshold, and categorizes the user input as containing less than a predetermined level of noise when the root mean square of the user input is not more than the predetermined threshold.

13. The computer readable medium of claim 10 ,

wherein the filtering code segment further compares a maximum amplitude of the user input with a predetermined threshold, and categorizes the user input as containing more than a predetermined level of noise when the maximum amplitude of the user input is not less than the predetermined threshold.

14. The computer readable medium of claim 10 , wherein the filtering code segment further determines whether the audio data contains user input.

15. The computer readable medium of claim 10 ,

wherein the correlated audio data is audio data having a level of noise within a predetermined range.

16. The computer readable medium of claim 10 ,

wherein the correlating code segment further correlates user input from the input channel with a scripted audible prompt provided over the output channel.

17. The computer readable medium of claim 16 ,

wherein the correlating code segment further correlates the predetermined duration of the user input with a predetermined length time of the scripted audible prompt, and classifies a correlation result according to a predetermined correlation threshold.

18. The computer readable medium of claim 10 , wherein the predetermined duration is approximately six seconds.

19. An echo residue detector associated with a speech application, comprising:

an input port through which audio data from an input channel is received;

an output port through which audio data from an output channel is transmitted; and

a processor that correlates the audio data from the input channel with the audio data from the output channel to obtain a correlation result;

wherein the processor filters audio data to determine whether the a audio data should be further analyzed;

wherein a determined value of the correlation result is compared with a predetermined threshold;

wherein the audio data for the input channel is categorized as including an acceptable level of residual echo when the determined value of the correlation result is greater than the predetermined threshold, and the audio data for the input channel is categorized as including an unacceptable level of residual echo when the determined value of the correlation result is less than the predetermined threshold; and

wherein the filtering comprises determining whether a duration of a user input is at least a predetermined duration, and when the user input is at least the predetermined duration, extracting a predetermined duration of the user input from of a total duration of the user input for further analysis, and when the user input is not at least the predetermined duration, ending the analysis.

20. The echo residue detector of claim 19 ,

wherein the filtering further includes comparing a root mean square of the user input with a predetermined maximum threshold, and categorizing the user input as containing more than a predetermined level of noise when the root mean square of the user input is not less than the predetermined threshold.

21. The echo residue detector of claim 19 ,

wherein the filtering further includes comparing a root mean square of the user input with a predetermined minimum threshold, and categorizing the user input as containing less than a predetermined level of noise when the root mean square of the user input is not greater than the predetermined threshold.

22. The echo residue detector of claim 19 ,

wherein the filtering further includes comparing a maximum amplitude of the user input with a predetermined threshold, and categorizing the user input as containing more than a predetermined level of noise when the maximum amplitude of the user input is not less than the predetermined threshold.

23. The echo residue detector of claim 19 ,

wherein the filtering further includes determining whether the audio data contains user input.

24. The echo residue detector of claim 19 ,

wherein the correlated audio data is audio data having a level of noise within a predetermined range.

25. The echo residue detector of claim 19 , wherein user input from the input channel is correlated with a scripted audible prompt provided over the output channel.

26. The echo residue detector of claim 19 , wherein the predetermined duration is approximately six seconds.