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Hi The latest SVN trunk for speex has changed the SpeexPreprocessState to an opaque structure, for jolly good software engineering reasons. However, the Analogue AGC (AAGC) feature of iaxclient (in audio_enode.c) relies on some members of this. It uses speech_prob to detect when there is enough speech to consider AAGC and then loudness2 to decide how to adjust the input mixer. We want to use the latest speex, for echo cancellation and other reasons, so I tried just...

> As you can tell, the AAGC integration with speex was really a classic > hack. Instead of re-creating the hack, what's probably best here is to > integrate AAGC back into speex, and have a proper API. Agreed here. If you can come up with a clean patch to add that feature, it's something I'd like to see in...

Jean-Marc Valin wrote: >> As you can tell, the AAGC integration with speex was really a classic >> hack. Instead of re-creating the hack, what's probably best here is to >> integrate AAGC back into speex, and have a proper API. >> > > Agreed here. If you can come up with a clean patch to add that feature, > it...

David Brazier wrote: > Hi > > The latest SVN trunk for speex has changed the SpeexPreprocessState to > an opaque structure, for jolly good software engineering reasons. > However, the Analogue AGC (AAGC) feature of iaxclient (in audio_enode.c) > relies on some members of this. It uses speech_prob to detect when > there is enough speech to consider AAGC and then loudness2 to decide how > to adjust the input mixer. We want to use the latest speex, for echo > cancellation and other reas...

...AD decision isn't used by > the consumer, right. Because the VAD decision needs to be used by AGC, > so that it isn't raising the gain of background noise (although it > should probably lower the gain when there's any signal higher than it's > threshold). > > For AAGC, though, I guess one way to do this would be if you could > somehow "transport" the un-cancelled, un-noise-suppressed energy level > past the VAD decision, and then used that to determine what gain > adjustments to make. In this fashion, you'd be making your adjustments >...

...sed by >> the consumer, right. Because the VAD decision needs to be used by AGC, >> so that it isn't raising the gain of background noise (although it >> should probably lower the gain when there's any signal higher than it's >> threshold). >> >> For AAGC, though, I guess one way to do this would be if you could >> somehow "transport" the un-cancelled, un-noise-suppressed energy level >> past the VAD decision, and then used that to determine what gain >> adjustments to make. In this fashion, you'd be making your adju...

...gain was increased > 4) wait a little while (e.g. 100 ms) > 5) unfreeze everyone Similar (same may be) mechanism may be used to prevent AEC upset in case user change mic or speaker (analog) gain manually. Application might detect all HW mixer changes and report them to speex library even if AAGC would not be used. Speex library will do essential actions to prevent AEC mess. So, there should be some generic API to notify Speex about HW mixer level changes. What do you think? -- Regards, Alexander Chemeris. SIPez LLC. SIP VoIP, IM and Presence Consulting http://www.SIPez.com tel: +1 (617...