Method, apparatus, system and software product for adaptation of voice activity detection parameters based oncoding modes
Encoding audio signals with selecting an encoding mode for encoding the signal categorizing the signal into active segments having voice activity and non-active segments having substantially no voice activity by using categorization parameters depending on the selected encoding mode and encoding at least the active segments using the selected encoding mode.
1. A method comprising:
dividing an audio signal temporally into segments;
selecting an encoding mode for encoding the segments;
categorizing the segments into active segments having voice activity and non-active segments having substantially no voice activity by using categorization parameters depending on the selected encoding mode;
encoding at least the active segments using the selected encoding mode.
2. The method of claim 1 , wherein the categorization parameters are such that for a low quality of the encoding mode a lower number of temporal sections are detected as active sections than for a high quality of the encoding mode.
3. The method of claim 1 , wherein the categorization parameters depend on the encoding bitrate of the encoding mode.
4. The method of claim 1 , further comprising obtaining network traffic of a network for which the audio signal is encoded and setting the categorization parameters depending on the obtained network traffic.
5. The method of claim 1 , further comprising obtaining background noise within the audio signal and setting the categorization parameters depending on the obtained background noise.
6. The method of claim 1 , wherein an energy threshold value is a categorization parameter and wherein categorizing the segments comprises comparing energy information of the audio signal to at least the energy threshold value.
7. The method of claim 1 , wherein a signal-to-noise threshold value is a categorization parameter and wherein categorizing the segments comprises comparing signal-to-noise information of the audio signal to at least the signal-to-noise threshold value.
8. The method of claim 1 , wherein pitch information is a categorization parameter and wherein categorizing the segments comprises comparing the pitch of the audio signal to at least the pitch information.
9. The method of claim 1 , wherein tone information is a categorization parameter and wherein categorizing the segments comprises comparing the tone of the audio signal to at least the tone information.
10. The method of claim 1 , further comprising creating spectral sub-bands from the audio signal.
11. The method of claim 10 , wherein categorizing the segments comprises categorizing selected sub-bands.
12. The method of claim 11 , wherein spectral information is a categorization parameter and wherein categorizing the segments comprises comparing spectral components of the audio signal to at least the spectral information.
13. An apparatus comprising:
a division unit arranged for dividing an audio signal temporally into segments;
an adaptive categorization unit arranged for categorizing the segments into active segments having voice activity and non-active segments having substantially no voice activity by using categorization parameters depending on a selected encoding mode;
a selection unit arranged for selecting an encoding mode for encoding the segments; and
an encoding unit arranged for encoding at least the active segments using the selected encoding mode.
14. The apparatus of claim 13 , wherein the adaptive categorization unit is arranged for setting the categorization parameters depending on the encoding bitrate of the encoding mode.
15. The apparatus of claim 13 , wherein the adaptive categorization unit is arranged for using an energy threshold value as a categorization parameter.
16. The apparatus of claim 13 , wherein the adaptive categorization unit is arranged for using spectral information as a categorization parameter.
17. The apparatus of claim 13 , wherein the adaptive categorization unit is arranged for using a signal-to-noise threshold value as a categorization parameter.
18. The apparatus of claim 13 , wherein the adaptive categorization unit is arranged for using pitch information as a categorization parameter.
19. The apparatus of claim 13 , wherein the adaptive categorization unit is arranged for using tone information as a categorization parameter.
20. The apparatus of claim 13 , wherein the adaptive categorization unit is arranged for using background noise information as a categorization parameter.
21. The apparatus of claim 13 , wherein the encoding unit further comprises one of an adaptive multirate encoder and an adaptive multirate wideband encoder.
22. An apparatus comprising:
division means for dividing an audio signal temporally into segments;
adaptive categorization means for categorizing the segments into active segments having voice activity and non-active segments having substantially no voice activity by using categorization parameters depending on a selected encoding mode;
selection means for selecting an encoding mode for encoding the segments; and
encoding means for encoding at least the active segments using the selected encoding mode.
23. A chipset comprising:
a division unit arranged for dividing an audio signal temporally into segments;
an adaptive categorization unit arranged for categorizing the segments into active segments having voice activity and non-active segments having substantially no voice activity by using categorization parameters depending on a selected encoding mode;
a selection unit arranged for selecting an encoding mode for encoding the segments; and
an encoding unit arranged for encoding at least the active segments using the selected encoding mode.
24. An audio system comprising:
a division unit arranged for dividing an audio signal temporally into segments;
an adaptive categorization unit arranged for categorizing the segments into active segments having voice activity and non-active segments having substantially no voice activity by using categorization parameters depending on a selected encoding mode;
a selection unit arranged for selecting an encoding mode for encoding the segments; and
an encoding unit arranged and encoding at least the active segments using the selected encoding mode.
25. The audio system of claim 24 , wherein the adaptive categorization unit is arranged for using at least one of the group comprising:
A) an encoding bitrate of the encoding mode for setting an categorization parameters
B) an energy threshold value as a categorization parameter;
C) a spectral information as a categorization parameter;
D) a signal-to-noise threshold value as a categorization parameter;
E) pitch information as a categorization parameter;
F) tone information as a categorization parameter;
G) background noise information is a categorization parameter.
26. A system comprising
a transmission network;
a transmitter comprising an audio encoder with
a division unit arranged for dividing an audio signal temporally into segments;
an adaptive categorization unit arranged for categorizing the segments into active segments having voice activity and non-active segments having substantially no voice activity by using categorization parameters depending on a selected encoding mode;
a selection unit arranged for selecting an encoding mode for encoding the segments; and
an encoding unit arranged for encoding at least the active segments using the selected encoding mode; and
a receiver for receiving the encoded audio signal.
27. A software program product in which a software code is stored in a readable medium, wherein said software code realizes the following when being executed by a processor:
dividing an audio signal temporally into segments;
selecting an encoding mode for encoding the segments;
categorizing the segments into active segments having voice activity and non-active segments having substantially no voice activity by using categorization parameters depending on the selected encoding mode;
encoding at least the active segments using the selected encoding mode.
28. The software program product of claim 27 , wherein categorizing comprises using at least one of the group comprising:
A) an encoding bitrate of the encoding mode for setting an categorization parameters
B) an energy threshold value as a categorization parameter;
C) a spectral information as a categorization parameter;
D) a signal-to-noise threshold value as a categorization parameter;
E) pitch information as a categorization parameter;
F) tone information as a categorization parameter;
G) background noise information is a categorization parameter.
29. A mobile device comprising the audio system of claim 22 .