Yep. That confirms my general impression, which is that 70% is about the highest rate of accuracy you're ever going to get, and it is possible to come reasonably close to that with Asterisk's built-in AMD.
The essence of the matter is that in general, over that 60-70% point come diminishing returns. Not even 80/20 diminishing returns - more like 95/5. Al Lougher wrote: > I'll give you my two cents, if only to give you a good idea of what you > can expect to uncover in your search for the holy grail of answer > machine detection systems. And as one of your competitors in this space > I cannot give away too many trade secrets :) > > Alex is right on the money, there is no best, or single, answer machine > detection process for asterisk based systems. AMD will only get you so > far. In fact, you'll find you'll need a combination of custom processes, > each one increasing the detection rate by a small %. There is a white > paper somewhere outlining issues with answer machine detection (if I > find it I'll send the URL) and even the research done in that paper > which tested some of the more advanced industry detection applications > gave an overall 70% accuracy in detecting machines. > > I can tell you that we employ a combination of customer AMD modules, > carrier detection, wireless detection, SOX silence stripping, > BackgroundDetect, DTMF and more just for our machine detection process. > It also took us two years to perfect it and yet every week we get the > "my message isn't being left on my voicemail" support issues. > > So as you can see the answer is not a single process but a combination > of processes that improves your overall detection rate. > > Hope this helps. > > Alan > www.group2call.com > > --- On *Tue, 10/7/08, Alex Balashov /<[EMAIL PROTECTED]>/* wrote: > > From: Alex Balashov <[EMAIL PROTECTED]> > Subject: Re: [asterisk-biz] Custom AMD Module for Improved Answering > Machine Detection Needed > To: "Commercial and Business-Oriented Asterisk Discussion" > <[email protected]> > Date: Tuesday, October 7, 2008, 9:56 PM > > The best off-the-shelf solution I've seen for this comes from Paraxip in > the form of their NetBorder CPA (Call Progress Analysis) product. They > use a B2BUA that you can send calls through out of Asterisk, and which > will return a certain code as a custom SIP header depending on the > disposition. > > "The best" still isn't saying much. You're going to get many > of the > same problems as you get with AMD. The marginal improved accuracy may > or may not be worth the cost. > > That's just how it is. This is impossible to do right in a way that is > applicable to the variance of environmental and acoustic situations - as > you mention, works with one carrier and not with another, and other > variables. Most likely, developing such a thing would be a pointless > waste of time and energy because to get beyond a certain rate of > accuracy is to ask for a perpetual motion machine. > > Just my $.02, > of course. > > Chris wrote: > > > We're looking for a company (preferably U.S. based) that can help us > > with the development of a custom module for advanced Answering Machine > > Detection. We need to be able to properly detect a live answer vs. an > > answering machine or voicemail (including cell phone ringbacks, etc.) > as > > well as wait for the beep to leave a message. We've tried tweaking > the > > built-in AMD settings for Asterisk, but all this accomplishes is > > improving detection rate for one carrier and eliminating it for > > another. We're looking for a company that has worked on similar > > projects before that could help us with a potential solution. Thanks > in > > advance! > > > > _______________________________________________ > > --Bandwidth and Colocation Provided by http://www.api-digital.com-- > > > > AstriCon 2008 - September 22 - 25 Phoenix, > Arizona > > Register Now: http://www.astricon.net > > > > asterisk-biz mailing list > > To UNSUBSCRIBE or update options visit: > > http://lists.digium.com/mailman/listinfo/asterisk-biz > > > -- > Alex Balashov > Evariste Systems > Web : http://www.evaristesys.com/ > Tel : (+1) (678) 954-0670 > Direct : (+1) (678) 954-0671 > Mobile : (+1) (706) 338-8599 > > _______________________________________________ > --Bandwidth and Colocation Provided by http://www.api-digital.com-- > > AstriCon 2008 - September 22 - 25 Phoenix, Arizona > Register Now: http://www.astricon.net > > asterisk-biz mailing list > To UNSUBSCRIBE or update options visit: > http://lists.digium.com/mailman/listinfo/asterisk-biz > > > > ------------------------------------------------------------------------ > > _______________________________________________ > --Bandwidth and Colocation Provided by http://www.api-digital.com-- > > AstriCon 2008 - September 22 - 25 Phoenix, Arizona > Register Now: http://www.astricon.net > > asterisk-biz mailing list > To UNSUBSCRIBE or update options visit: > http://lists.digium.com/mailman/listinfo/asterisk-biz -- Alex Balashov Evariste Systems Web : http://www.evaristesys.com/ Tel : (+1) (678) 954-0670 Direct : (+1) (678) 954-0671 Mobile : (+1) (706) 338-8599 _______________________________________________ --Bandwidth and Colocation Provided by http://www.api-digital.com-- asterisk-biz mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-biz
