Tim, (I am not answering for Shuba but she is on vacation so you get my views instead) Another viewpoint could be that AEC should really not be a vendor provided feature or an attribute of the microphone or any other capture hardware but should rather be inherently built into OS APIs because it is so necessary for some applications to function and because applications don't want to rely on the user having a certain driver/filter driver/APO installed or specific capture hardware connected. Enabling applications (who one could argue owns the total user experience for that application and should be able to control it) to make use of a universally known and always present/available AEC may be a better solution than inserting 3rd party processing into the pipeline that the application may not even be aware of, the application may not be able to control or that may not be there on all systems. Please email us directly if you want to continue a philosophical discussion about the different approaches to value-add enabling in Windows Vista. Sincerely, Hakon Strande (hakons@xxxxxxxxxxxxx) Program Manager Integrated, Internal, External, and Wireless Audio Devices MediaTech/DMD/Windows Client/Microsoft ________________________________ From: wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of Tim Roberts Sent: Wednesday, October 04, 2006 10:20 AM To: wdmaudiodev@xxxxxxxxxxxxx Subject: [wdmaudiodev] Re: AEC in Vista Shuba Iyer wrote: AEC and microphone array processing in Vista are application graph features. So it is up to the application to use the feature or not. You know, the more I think about this statement, the more I think this position is completely wrong. AEC is perhaps "the" canonical feature that one would want to use globally. As a user, I'm not going to think about AEC as an application add-on. Instead, I'm going to think about AEC as an attribute of the microphone array. If I have installed some kind of AEC, then I want echo cancellation in every application that uses that microphone, whether it be wave, DSound, or WASAPI. I've been using Sound Recorder as an example, but that's the wrong example. With the policy you have described, there is no way to use an AEC-enabled microphone with NetMeeting, which is one of the apps where I would most want echo cancellation. In fact, if I am a vendor supplying my own AEC DMO following your model, there is no way to have it get used by any applications other than the ones I have written myself. That ain't right. Have I misunderstood your position? -- Tim Roberts, timr@xxxxxxxxx Providenza & Boekelheide, Inc.