Hello everyone. I know a lot about echo was said. Actually I don't understand how, when using same box with microphone, with skype there is no echo, while using sip client, echo is quite loud. On the same hardware different programs acts differently. If its client's job to remove echo, then why none of tried sip clients does not remove echo? If there is a good sip client which handles echo removal in box+microphone please advise. -- Mimiko desu.
I feel your pain. The number one complaint from my customers switching to VOIP is the frequent presence of echo. Many times the echo is quite quiet and is easily ignored. Other times it is neither soft nor a short delay increasing the annoyance level. (The number 2 complaint is delay in connecting to the number being called). I have read LOTS of articles and blogs and wikis on the subject. The prevailing wisdom seems to be: 1. The echo is always caused by the phone or equipment on the far end of your call! Presumably the phone or device on the far end of the call does not have good echo cancellation. My question is "If so, why is it ALMOST exclusively a VOIP problem?" Also, for FS developers, "Why is it so much more prevalent than when I was on Vonage for years?" 2. VOIP is clearer than analog. The times when nobody is speaking on VOIP can even cause "Are you still there?" questions. That exacerbates the echo problem. When the quite levels are SO quiet, a little echo goes a long way. 3. A significant number people have just adopted the idea that "Echo is part of life, get used to it. Also, tell the person you are talking to they need a phone upgrade." I will attest to having had my business partner switch from speaker to handset to headphone and noticed a perceivable difference in echo levels. So, Anthony et. al. is this something that COULD be addressed if we put a ransom on it or is it just beyond the scope of what can be done in FS? Analog providers and Vonage have addressed the issue to the point that people are content. My customers are far from content. I THINK we could raise some real money if this is fixable - I would start the pot with a couple of hundred bucks. On the other hand, I am ignorant of the underlying issues and those other folks may have very expensive hardware addressing the issue. Please educate me. As a follow up question, does my VOIP topology affect this issue? I use a fairly large, fast, dedicated server collocated at my primary VOIP provider for fastest connect speeds. ALL of my users (and I) are remote connects. I get varying levels of echo calling from my Cisco SPA504G in Baltimore to my partner on his Cisco504G in Milwaukee on the same FS box. Granted it is usually quite low levels in that scenario, but it is sporadically quite annoying. The worst part is having NO ANSWER for (new) customers. Sean -----Original Message----- From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Mimiko Sent: Sunday, March 17, 2013 8:49 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Removing echo. Some one. Some thought about this? -- Mimiko desu. _________________________________________________________________________ Professional FreeSWITCH Consulting Services: <mailto:consulting@freeswitch.org> consulting@freeswitch.org <http://www.freeswitchsolutions.com> http://www.freeswitchsolutions.com FreeSWITCH-powered IP PBX: The CudaTel Communication Server <http://www.cudatel.com> http://www.cudatel.com Official FreeSWITCH Sites <http://www.freeswitch.org> http://www.freeswitch.org <http://wiki.freeswitch.org> http://wiki.freeswitch.org <http://www.cluecon.com> http://www.cluecon.com FreeSWITCH-users mailing list <mailto:FreeSWITCH-users@lists.freeswitch.org> FreeSWITCH-users@lists.freeswitch.org <http://lists.freeswitch.org/mailman/listinfo/freeswitch-users> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users <http://www.freeswitch.org> http://www.freeswitch.org
Dear Sean Devoy, overall switching to VoIP is not painful until boxes is implied. Actually almost every phone operator already switched to VoIP in theirs core, leaving analog phones to clients. Using FS I don't hear any quality loss, delay, connection delay, echo when using normal clients, ie. VoIP phones or SIP clients with headsets. Especially connection delay is virtually zero. I see this with pressing calling and immediately starting call the other end which is connected thru two phone operators. Nor audio delay I hear if internet channel is not full loaded. Skype is the same VoIP just using different protocol. And you are right, hearing echo is the other end problem. Generally, VoIP can not induce echo in wires, as each direction is send using packets, compared to analog phones where echo is heard (especially on long distant) because of wire induction. My wander is how skype client (or may be server) does echo removing on same client which uses boxes and microphone which will create the echo. May be there are SIP clients which removes echo o client like skype client does. We tried here to connect two clients with FS (it may be asterisk or other server it is no matter) both using boxes and microphone. Its not only echo we get, but also a sound loop getting louder and louder. Same clients switch to skype call and no echo, clear sound. This is a step forward to using VoIP and not skype. -- Mimiko desu.
I think its the atas peopel are using -- vonage, etc. have specific ones which apparently work and they have the settings locked down on both sides. Sean Devoy <sdevoy@bizfocused.com> wrote:
I feel your pain. The number one complaint from my customers switching to VOIP is the frequent presence of echo. Many times the echo is quite quiet and is easily ignored. Other times it is neither soft nor a short delay increasing the annoyance level. (The number 2 complaint is delay in connecting to the number being called).
I have read LOTS of articles and blogs and wikis on the subject. The prevailing wisdom seems to be:
1. The echo is always caused by the phone or equipment on the far end of your call! Presumably the phone or device on the far end of the call does not have good echo cancellation. My question is "If so, why is it ALMOST exclusively a VOIP problem?" Also, for FS developers, "Why is it so much more prevalent than when I was on Vonage for years?"
2. VOIP is clearer than analog. The times when nobody is speaking on VOIP can even cause "Are you still there?" questions. That exacerbates the echo problem. When the quite levels are SO quiet, a little echo goes a long way.
3. A significant number people have just adopted the idea that "Echo is part of life, get used to it. Also, tell the person you are talking to they need a phone upgrade." I will attest to having had my business partner switch from speaker to handset to headphone and noticed a perceivable difference in echo levels.
So, Anthony et. al. is this something that COULD be addressed if we put a ransom on it or is it just beyond the scope of what can be done in FS? Analog providers and Vonage have addressed the issue to the point that people are content. My customers are far from content. I THINK we could raise some real money if this is fixable - I would start the pot with a couple of hundred bucks. On the other hand, I am ignorant of the underlying issues and those other folks may have very expensive hardware addressing the issue. Please educate me.
As a follow up question, does my VOIP topology affect this issue? I use a fairly large, fast, dedicated server collocated at my primary VOIP provider for fastest connect speeds. ALL of my users (and I) are remote connects. I get varying levels of echo calling from my Cisco SPA504G in Baltimore to my partner on his Cisco504G in Milwaukee on the same FS box. Granted it is usually quite low levels in that scenario, but it is sporadically quite annoying. The worst part is having NO ANSWER for (new) customers.
Sean
-----Original Message----- From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Mimiko Sent: Sunday, March 17, 2013 8:49 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Removing echo.
Some one. Some thought about this?
--
Mimiko desu.
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Sean, Since, as you said, the problem is usually due to equipment on the far-end, replacing this equipment is usually expensive and a non-practical solution. On the other hand, you can easily upgrade your VoIP infrastructure by installing a commercial solutions for network echo cancellation like the PBXMate. ________________________________ From: Sean Devoy <sdevoy@bizfocused.com> To: 'FreeSWITCH Users Help' <freeswitch-users@lists.freeswitch.org> Sent: Sunday, March 17, 2013 6:56 PM Subject: Re: [Freeswitch-users] Removing echo. I feel your pain. The number one complaint from my customers switching to VOIP is the frequent presence of echo. Many times the echo is quite quiet and is easily ignored. Other times it is neither soft nor a short delay increasing the annoyance level. (The number 2 complaint is delay in connecting to the number being called). I have read LOTS of articles and blogs and wikis on the subject. The prevailing wisdom seems to be: 1. The echo is always caused by the phone or equipment on the far end of your call! Presumably the phone or device on the far end of the call does not have good echo cancellation. My question is “If so, why is it ALMOST exclusively a VOIP problem?” Also, for FS developers, “Why is it so much more prevalent than when I was on Vonage for years?” 2. VOIP is clearer than analog. The times when nobody is speaking on VOIP can even cause “Are you still there?” questions. That exacerbates the echo problem. When the quite levels are SO quiet, a little echo goes a long way. 3. A significant number people have just adopted the idea that “Echo is part of life, get used to it. Also, tell the person you are talking to they need a phone upgrade.” I will attest to having had my business partner switch from speaker to handset to headphone and noticed a perceivable difference in echo levels. So, Anthony et. al. is this something that COULD be addressed if we put a ransom on it or is it just beyond the scope of what can be done in FS? Analog providers and Vonage have addressed the issue to the point that people are content. My customers are far from content. I THINK we could raise some real money if this is fixable – I would start the pot with a couple of hundred bucks. On the other hand, I am ignorant of the underlying issues and those other folks may have very expensive hardware addressing the issue. Please educate me. As a follow up question, does my VOIP topology affect this issue? I use a fairly large, fast, dedicated server collocated at my primary VOIP provider for fastest connect speeds. ALL of my users (and I) are remote connects. I get varying levels of echo calling from my Cisco SPA504G in Baltimore to my partner on his Cisco504G in Milwaukee on the same FS box. Granted it is usually quite low levels in that scenario, but it is sporadically quite annoying. The worst part is having NO ANSWER for (new) customers. Sean -----Original Message----- From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Mimiko Sent: Sunday, March 17, 2013 8:49 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Removing echo. Some one. Some thought about this? -- Mimiko desu. _________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org _________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
I am afraid I have offended some of you with my last email, I certainly did not mean to in any way. I love FS and I am interested in making it better if I can help. I have sent a request for pricing from PBXMate, but my experience is that if they won’t put it on the website it is going to be too high. I was just trying to see if there was interest from others in PAYING Anthony and the other developers to add this to FreeSwitch. I would certainly rather send money to FS developers than to a commercial product vendor if possible. Having said all that, does anyone have experience with PBXMate? Does it cancel echo well? Sean From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Valer Nur Sent: Monday, March 18, 2013 3:02 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Removing echo. Sean, Since, as you said, the problem is usually due to equipment on the far-end, replacing this equipment is usually expensive and a non-practical solution. On the other hand, you can easily upgrade your VoIP infrastructure by installing a commercial solutions for network echo cancellation like the PBXMate. _____ From: Sean Devoy <sdevoy@bizfocused.com> To: 'FreeSWITCH Users Help' <freeswitch-users@lists.freeswitch.org> Sent: Sunday, March 17, 2013 6:56 PM Subject: Re: [Freeswitch-users] Removing echo. I feel your pain. The number one complaint from my customers switching to VOIP is the frequent presence of echo. Many times the echo is quite quiet and is easily ignored. Other times it is neither soft nor a short delay increasing the annoyance level. (The number 2 complaint is delay in connecting to the number being called). I have read LOTS of articles and blogs and wikis on the subject. The prevailing wisdom seems to be: 1. The echo is always caused by the phone or equipment on the far end of your call! Presumably the phone or device on the far end of the call does not have good echo cancellation. My question is “If so, why is it ALMOST exclusively a VOIP problem?” Also, for FS developers, “Why is it so much more prevalent than when I was on Vonage for years?” 2. VOIP is clearer than analog. The times when nobody is speaking on VOIP can even cause “Are you still there?” questions. That exacerbates the echo problem. When the quite levels are SO quiet, a little echo goes a long way. 3. A significant number people have just adopted the idea that “Echo is part of life, get used to it. Also, tell the person you are talking to they need a phone upgrade.” I will attest to having had my business partner switch from speaker to handset to headphone and noticed a perceivable difference in echo levels. So, Anthony et. al. is this something that COULD be addressed if we put a ransom on it or is it just beyond the scope of what can be done in FS? Analog providers and Vonage have addressed the issue to the point that people are content. My customers are far from content. I THINK we could raise some real money if this is fixable – I would start the pot with a couple of hundred bucks. On the other hand, I am ignorant of the underlying issues and those other folks may have very expensive hardware addressing the issue. Please educate me. As a follow up question, does my VOIP topology affect this issue? I use a fairly large, fast, dedicated server collocated at my primary VOIP provider for fastest connect speeds. ALL of my users (and I) are remote connects. I get varying levels of echo calling from my Cisco SPA504G in Baltimore to my partner on his Cisco504G in Milwaukee on the same FS box. Granted it is usually quite low levels in that scenario, but it is sporadically quite annoying. The worst part is having NO ANSWER for (new) customers. Sean -----Original Message----- From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Mimiko Sent: Sunday, March 17, 2013 8:49 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Removing echo. Some one. Some thought about this? -- Mimiko desu. _________________________________________________________________________ Professional FreeSWITCH Consulting Services: <mailto:consulting@freeswitch.org> consulting@freeswitch.org <http://www.freeswitchsolutions.com/> http://www.freeswitchsolutions.com FreeSWITCH-powered IP PBX: The CudaTel Communication Server <http://www.cudatel.com/> http://www.cudatel.com Official FreeSWITCH Sites <http://www.freeswitch.org/> http://www.freeswitch.org <http://wiki.freeswitch.org/> http://wiki.freeswitch.org <http://www.cluecon.com/> http://www.cluecon.com FreeSWITCH-users mailing list <mailto:FreeSWITCH-users@lists.freeswitch.org> FreeSWITCH-users@lists.freeswitch.org <http://lists.freeswitch.org/mailman/listinfo/freeswitch-users> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users <http://www.freeswitch.org/> http://www.freeswitch.org _________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com <http://www.freeswitchsolutions.com/> FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com <http://www.cudatel.com/> Official FreeSWITCH Sites http://www.freeswitch.org <http://www.freeswitch.org/> http://wiki.freeswitch.org <http://wiki.freeswitch.org/> http://www.cluecon.com <http://www.cluecon.com/> FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org <http://www.freeswitch.org/>
Today we tried ooVoo conference system with theirs client using same boxes and microphones - again, no echo. How this can be? Is it only commercial products have echo removing function? -- Mimiko desu.
Echo cancellation is not easy. The only open source one I've seen is GPL (making it license incompatible with FreeSWITCH) and is not suitable for handling echo over IP networks. Perhaps tricks are being played using VAD to only allow only one speaker at a time in the ooVoo conference? On Mon, Mar 18, 2013 at 5:53 PM, Mimiko <vbvbrj@gmail.com> wrote:
Today we tried ooVoo conference system with theirs client using same boxes and microphones - again, no echo. How this can be? Is it only commercial products have echo removing function?
-- Mimiko desu.
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
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The best place for echo cancelation is in the clients as close to the mic as possible. Someone asked why skype and some apps are better. It's because they have echo cans in the client app. Sip soft phones are basically toys unless they have some kind of advanced gain and echo controls on your pc because that is where your mic is and could have the vol turned up too high etc.
From FS perspective in the middle, we can't tell its echo or not because we are just passing the data along and we're typically getting it 30-70 ms too late.
In general, you don't get echo when using real phones because they have proper hardware and software to deal with the place where the audio is being sampled and rendered. On Mon, Mar 18, 2013 at 5:15 PM, Christopher Rienzo <cmrienzo@gmail.com>wrote:
Echo cancellation is not easy. The only open source one I've seen is GPL (making it license incompatible with FreeSWITCH) and is not suitable for handling echo over IP networks. Perhaps tricks are being played using VAD to only allow only one speaker at a time in the ooVoo conference?
On Mon, Mar 18, 2013 at 5:53 PM, Mimiko <vbvbrj@gmail.com> wrote:
Today we tried ooVoo conference system with theirs client using same boxes and microphones - again, no echo. How this can be? Is it only commercial products have echo removing function?
-- Mimiko desu.
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
-- Anthony Minessale II FreeSWITCH http://www.freeswitch.org/ ClueCon http://www.cluecon.com/ Twitter: http://twitter.com/FreeSWITCH_wire AIM: anthm MSN:anthony_minessale@hotmail.com GTALK/JABBER/PAYPAL:anthony.minessale@gmail.com IRC: irc.freenode.net #freeswitch FreeSWITCH Developer Conference sip:888@conference.freeswitch.org googletalk:conf+888@conference.freeswitch.org pstn:+19193869900
Hey Anthony, Does that mean PBXMate is not worth investigating? I have to disagree here. Placing the blame entirely on the phones at the other end doesn't hold water for me. I have had echo problems calling from my cell phone when leaving a voice mail on FS where there is no phone at the other end. So clearly there are situations where it ain't just the phone at the other end. It also leaves no explanation why Cisco Phones and Linksys ATAs don't have the same problem with Commercial Venders like Vonage. They don't have anything different at the end of the line for echo cancellation then FS does. I have also had users confirm they are still getting echo with the microphone MUTED on my end. Again, I love FS and I am not trying to bash anyone or any code. I am just saying there has to be more to this puzzle. I know what a crappy speaker phone's echo sounds like and I am not at all concerned about that. Crappy speaker phones sound like crappy speaker phones no matter what. I don't think that's what I am trying to track down. These are business call where 90% are using the standard handset on business quality phones. It happens at various levels, but when it is at the bad end of the spectrum (e.g. long delay and loud), it does not sound like echo off of walls coming back in a microphone. It is like my input channel has been delayed, softened and looped directly back to me crystal clear. Maybe it is one of my VOIP providers' hardware or software and is load dependent, but the problem exists outside of cheap phones. And of course it is only reproducible on 3 calls in a hundred at peak usage hours, making it a nightmare to track or diagnose. But those 3 calls are the ones my customers want to talk about at billing time. Now, I have just thrown that all out there is hopes that 50 people will say "That absolutely never happens to me with FS" so I can look at it a different way. Thanks for your thoughts. Sean From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Anthony Minessale Sent: Monday, March 18, 2013 7:30 PM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Removing echo. The best place for echo cancelation is in the clients as close to the mic as possible. Someone asked why skype and some apps are better. It's because they have echo cans in the client app. Sip soft phones are basically toys unless they have some kind of advanced gain and echo controls on your pc because that is where your mic is and could have the vol turned up too high etc.
From FS perspective in the middle, we can't tell its echo or not because we are just passing the data along and we're typically getting it 30-70 ms too late.
In general, you don't get echo when using real phones because they have proper hardware and software to deal with the place where the audio is being sampled and rendered. On Mon, Mar 18, 2013 at 5:15 PM, Christopher Rienzo <cmrienzo@gmail.com> wrote: Echo cancellation is not easy. The only open source one I've seen is GPL (making it license incompatible with FreeSWITCH) and is not suitable for handling echo over IP networks. Perhaps tricks are being played using VAD to only allow only one speaker at a time in the ooVoo conference? On Mon, Mar 18, 2013 at 5:53 PM, Mimiko <vbvbrj@gmail.com> wrote: Today we tried ooVoo conference system with theirs client using same boxes and microphones - again, no echo. How this can be? Is it only commercial products have echo removing function? -- Mimiko desu. _________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org _________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org -- Anthony Minessale II FreeSWITCH http://www.freeswitch.org/ ClueCon http://www.cluecon.com/ Twitter: http://twitter.com/FreeSWITCH_wire AIM: anthm MSN:anthony_minessale@hotmail.com <mailto:MSN%3Aanthony_minessale@hotmail.com> GTALK/JABBER/PAYPAL:anthony.minessale@gmail.com <mailto:PAYPAL%3Aanthony.minessale@gmail.com> IRC: irc.freenode.net #freeswitch FreeSWITCH Developer Conference sip:888@conference.freeswitch.org <mailto:sip%3A888@conference.freeswitch.org> googletalk:conf+888@conference.freeswitch.org <mailto:googletalk%3Aconf%2B888@conference.freeswitch.org> pstn:+19193869900
On 03/19/2013 10:24 AM, Sean Devoy wrote:
Hey Anthony,
Does that mean PBXMate is not worth investigating?
I have to disagree here. Placing the blame entirely on the phones at the other end doesn’t hold water for me. I have had echo problems calling from my cell phone when leaving a voice mail on FS where there is no phone at the other end. So clearly there are situations where it ain’t just the phone at the other end. It also leaves no explanation why Cisco Phones and Linksys ATAs don’t have the same problem with Commercial Venders like Vonage. They don’t have anything different at the end of the line for echo cancellation then FS does. I have also had users confirm they are still getting echo with the microphone MUTED on my end.
If you want to understand why a call from a cell phone to an FS server, leaving a voice mail, might result in you hearing echo, you'll have to describe the path between you and the FS server. Steve
-----Original Message----- From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Steve Underwood Sent: Tuesday, March 19, 2013 3:32 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Removing echo. On 03/19/2013 10:24 AM, Sean Devoy wrote:
Hey Anthony,
Does that mean PBXMate is not worth investigating?
I have to disagree here. Placing the blame entirely on the phones at
the other end doesn't hold water for me. I have had echo problems
calling from my cell phone when leaving a voice mail on FS where there
is no phone at the other end. So clearly there are situations where it
ain't just the phone at the other end. It also leaves no explanation
why Cisco Phones and Linksys ATAs don't have the same problem with
Commercial Venders like Vonage. They don't have anything different at
the end of the line for echo cancellation then FS does. I have also
had users confirm they are still getting echo with the microphone
MUTED on my end.
If you want to understand why a call from a cell phone to an FS server, leaving a voice mail, might result in you hearing echo, you'll have to describe the path between you and the FS server. Cell Phone => Cell Carrier => ?? => Internet => Voip Provider => LAN => FS Steve _________________________________________________________________________ Professional FreeSWITCH Consulting Services: <mailto:consulting@freeswitch.org> consulting@freeswitch.org <http://www.freeswitchsolutions.com> http://www.freeswitchsolutions.com FreeSWITCH-powered IP PBX: The CudaTel Communication Server <http://www.cudatel.com> http://www.cudatel.com Official FreeSWITCH Sites <http://www.freeswitch.org> http://www.freeswitch.org <http://wiki.freeswitch.org> http://wiki.freeswitch.org <http://www.cluecon.com> http://www.cluecon.com FreeSWITCH-users mailing list <mailto:FreeSWITCH-users@lists.freeswitch.org> FreeSWITCH-users@lists.freeswitch.org <http://lists.freeswitch.org/mailman/listinfo/freeswitch-users> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users <http://www.freeswitch.org> http://www.freeswitch.org
On 03/19/2013 09:10 PM, Sean Devoy wrote:
-----Original Message----- From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Steve Underwood Sent: Tuesday, March 19, 2013 3:32 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Removing echo.
If you want to understand why a call from a cell phone to an FS server, leaving a voice mail, might result in you hearing echo, you'll have to describe the path between you and the FS server.
Cell Phone => Cell Carrier => ?? => Internet => Voip Provider => LAN => FS
FS is definitely not the source of the echo in this path. When sending voice mail to FS is has distinct receive and transmit paths, with no possibility of crosstalk. The only way FS could introduce echo is if the call comes in through an analogue PSTN connexion. You don't have those, so FS is not to blame. The LAN surely isn't to blame. You indicated the VoIP provider has an internet path coming in. If that is true they probably can't be the source of the echo, as they will just pass the signals through. ?? looks like the probable rogue here. Presumably the cell carrier interfaces to the PSTN, and ?? is some VoIP provider interfacing between the PSTN and the IP world. A large VoIP provider would interface to the PSTN with a digital connection, and echo would not occur. However, don't rule out the possibility of some small outfit using analogue lines. There is a slight possibility of the cell carrier being at fault, although it is unlikely. In the early days of GSM it was quite common for a call that didn't connect properly to result in a huge echo to the user. This was because of bugs in the way the base station's echo canceller was handled. Over the years the bugs causing this have mostly been resolved, but you still get massive echo occasionally. It is not unknown for a particular call path to keep fooling the echo canceller during its adaption phase, so almost every call over the same path results in echo. The cell phone has an echo canceller to prevent earpiece to mic leakage from sending an echo back to the line, but this will not affect the user of the phone. The phone itself should not be the cause of your problem. So...... its looking like ?? is the probable problem area. I assume the use of ?? means you have no idea what is there. Can you try an alternate way to get from your cell phone to the FS box. Perhaps using a different VoIP provider who can be assumed to provide a genuinely different path? Steve
Hi, I would also vote for some EC tuning possibility in FS, even if it's not the "right place". I have an installation which uses an ISDN/SIP-Gateway (with its own EC).
Telco - ISDN - ISDN-/SIP-Gateway - FS - Phone Sometimes they hear an echo which I can record to a sound file with the FS record command. The echo is unfortunately not reliably reproducible, not even to the same destination number.
After some discussions with the vendor of the gateway they asked me to connect a phone directly to their gateway. And from that phone we never heard an echo (which is strange, I know). Currently I don't have any clue what the source of the echo is, but if FS could be tuned in that way I might get rid of it. Thanks Klaus -----Ursprüngliche Nachricht----- Von: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] Im Auftrag von Steve Underwood Gesendet: Mittwoch, 20. März 2013 03:14 An: FreeSWITCH Users Help Betreff: Re: [Freeswitch-users] Removing echo. On 03/19/2013 09:10 PM, Sean Devoy wrote:
-----Original Message----- From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Steve Underwood Sent: Tuesday, March 19, 2013 3:32 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Removing echo.
If you want to understand why a call from a cell phone to an FS server, leaving a voice mail, might result in you hearing echo, you'll have to describe the path between you and the FS server.
Cell Phone => Cell Carrier => ?? => Internet => Voip Provider => LAN => FS
FS is definitely not the source of the echo in this path. When sending voice mail to FS is has distinct receive and transmit paths, with no possibility of crosstalk. The only way FS could introduce echo is if the call comes in through an analogue PSTN connexion. You don't have those, so FS is not to blame. The LAN surely isn't to blame. You indicated the VoIP provider has an internet path coming in. If that is true they probably can't be the source of the echo, as they will just pass the signals through. ?? looks like the probable rogue here. Presumably the cell carrier interfaces to the PSTN, and ?? is some VoIP provider interfacing between the PSTN and the IP world. A large VoIP provider would interface to the PSTN with a digital connection, and echo would not occur. However, don't rule out the possibility of some small outfit using analogue lines. There is a slight possibility of the cell carrier being at fault, although it is unlikely. In the early days of GSM it was quite common for a call that didn't connect properly to result in a huge echo to the user. This was because of bugs in the way the base station's echo canceller was handled. Over the years the bugs causing this have mostly been resolved, but you still get massive echo occasionally. It is not unknown for a particular call path to keep fooling the echo canceller during its adaption phase, so almost every call over the same path results in echo. The cell phone has an echo canceller to prevent earpiece to mic leakage from sending an echo back to the line, but this will not affect the user of the phone. The phone itself should not be the cause of your problem. So...... its looking like ?? is the probable problem area. I assume the use of ?? means you have no idea what is there. Can you try an alternate way to get from your cell phone to the FS box. Perhaps using a different VoIP provider who can be assumed to provide a genuinely different path? Steve _________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
Hi, Klaus Additional delays in RTP network path (including delay added by freeswitch too) occured in this situation. So sometimes your phone can't compensate echo, if the overall audio delay from 'other end' more then echo compensator can compute. Best Wishes, Dmitry. 2013/3/25 Klaus Hochlehnert <Mailings@kh-dev.de>
Hi,
I would also vote for some EC tuning possibility in FS, even if it's not the "right place".
I have an installation which uses an ISDN/SIP-Gateway (with its own EC).
Telco - ISDN - ISDN-/SIP-Gateway - FS - Phone Sometimes they hear an echo which I can record to a sound file with the FS record command. The echo is unfortunately not reliably reproducible, not even to the same destination number.
After some discussions with the vendor of the gateway they asked me to connect a phone directly to their gateway. And from that phone we never heard an echo (which is strange, I know).
Currently I don't have any clue what the source of the echo is, but if FS could be tuned in that way I might get rid of it.
Thanks Klaus
-----Ursprüngliche Nachricht----- Von: freeswitch-users-bounces@lists.freeswitch.org [mailto: freeswitch-users-bounces@lists.freeswitch.org] Im Auftrag von Steve Underwood Gesendet: Mittwoch, 20. März 2013 03:14 An: FreeSWITCH Users Help Betreff: Re: [Freeswitch-users] Removing echo.
On 03/19/2013 09:10 PM, Sean Devoy wrote:
-----Original Message----- From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Steve Underwood Sent: Tuesday, March 19, 2013 3:32 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Removing echo.
If you want to understand why a call from a cell phone to an FS server, leaving a voice mail, might result in you hearing echo, you'll have to describe the path between you and the FS server.
Cell Phone => Cell Carrier => ?? => Internet => Voip Provider => LAN => FS
FS is definitely not the source of the echo in this path. When sending voice mail to FS is has distinct receive and transmit paths, with no possibility of crosstalk. The only way FS could introduce echo is if the call comes in through an analogue PSTN connexion. You don't have those, so FS is not to blame.
The LAN surely isn't to blame.
You indicated the VoIP provider has an internet path coming in. If that is true they probably can't be the source of the echo, as they will just pass the signals through.
?? looks like the probable rogue here. Presumably the cell carrier interfaces to the PSTN, and ?? is some VoIP provider interfacing between the PSTN and the IP world. A large VoIP provider would interface to the PSTN with a digital connection, and echo would not occur. However, don't rule out the possibility of some small outfit using analogue lines.
There is a slight possibility of the cell carrier being at fault, although it is unlikely. In the early days of GSM it was quite common for a call that didn't connect properly to result in a huge echo to the user. This was because of bugs in the way the base station's echo canceller was handled. Over the years the bugs causing this have mostly been resolved, but you still get massive echo occasionally. It is not unknown for a particular call path to keep fooling the echo canceller during its adaption phase, so almost every call over the same path results in echo.
The cell phone has an echo canceller to prevent earpiece to mic leakage from sending an echo back to the line, but this will not affect the user of the phone. The phone itself should not be the cause of your problem.
So...... its looking like ?? is the probable problem area. I assume the use of ?? means you have no idea what is there. Can you try an alternate way to get from your cell phone to the FS box. Perhaps using a different VoIP provider who can be assumed to provide a genuinely different path?
Steve
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
Guys, starting this topic I meant about removing echo when only SIP is involved. Analog lines always have echoes which is induced in wires. The most problem to resolve when moving to VoIP is eliminating echo whit SIP clients, like other VoIP solutions does. This means a proper free SIP client which will handle echo removing in case of speakers and microphone on client side. I don't think FS could handle this. -- Mimiko desu.
On 03/19/2013 02:32 AM, Steve Underwood wrote:
On 03/19/2013 10:24 AM, Sean Devoy wrote:
Hey Anthony,
Does that mean PBXMate is not worth investigating?
I have to disagree here. Placing the blame entirely on the phones at the other end doesn’t hold water for me. I have had echo problems calling from my cell phone when leaving a voice mail on FS where there is no phone at the other end. So clearly there are situations where it ain’t just the phone at the other end. It also leaves no explanation why Cisco Phones and Linksys ATAs don’t have the same problem with Commercial Venders like Vonage. They don’t have anything different at the end of the line for echo cancellation then FS does. I have also had users confirm they are still getting echo with the microphone MUTED on my end.
If you want to understand why a call from a cell phone to an FS server, leaving a voice mail, might result in you hearing echo, you'll have to describe the path between you and the FS server.
Steve
In fact, to add to what Steve said, sometimes when I make cellphone to cellphone calls completely independent of FS and any other infrastructure under my own control I hear echo. One of the most common causes of echo in my own personal experience is caused by volumes and microphone sensitivity being set too high. -Yossi
Sean, You are welcome to disagree. Science is driven by people being unwilling to accept things as they are. I do have some explanations for you if you are interested. Cisco and Linksys ATA both have echo cancelers in them at the point where the analog data is converted to digital. This is the ideal place for it as I mentioned earlier. So they actually are doing something about the problem and that is why you do not observe one. Getting echo while using a cell phone is also very common. The more latency and conversion of the audio data you experience, the more likely you can have echo. (iPhone is notorious) The other place where its important to have echo cancellation is the point where the digital data in the rtp stream is transferred into the TDM gateway interfacing with the PSTN. This is why most TDM cards like Digium and Sangoma have onboard echo canceler chips. We are not completely helpless, we can do some unnatural things like decode the audio signal we are passing through and try to run some echo cancellation on it but, in the conditions you describe where you hear a perfect replica of what you are saying 2-5 seconds later only softer. That is for sure outside the range of any echo canceler. It cannot reliably tell that this clean signal coming many seconds later should be filtered out because its a replica of data that has already passed by long before. Usually in this type of issue, you are actually hearing the other side hear what you said. So you say the statement, the latency takes its toll and the echo is coming back at you from the far end as they are hearing it. I am open to options. We do have some work on doing some inline audio processing underway but we should not rely on them if we can possibly control the surroundings better first. If you are talking to me in the same room using a megaphone and I am wearing ear plugs. Its easier to tell you to turn off the megaphone and tell me to remove the ear plugs. On Mon, Mar 18, 2013 at 9:24 PM, Sean Devoy <sdevoy@bizfocused.com> wrote:
Hey Anthony,****
** **
Does that mean PBXMate is not worth investigating?****
** **
I have to disagree here. Placing the blame entirely on the phones at the other end doesn’t hold water for me. I have had echo problems calling from my cell phone when leaving a voice mail on FS where there is no phone at the other end. So clearly there are situations where it ain’t just the phone at the other end. It also leaves no explanation why Cisco Phones and Linksys ATAs don’t have the same problem with Commercial Venders like Vonage. They don’t have anything different at the end of the line for echo cancellation then FS does. I have also had users confirm they are still getting echo with the microphone MUTED on my end.****
** **
Again, I love FS and I am not trying to bash anyone or any code. I am just saying there has to be more to this puzzle. I know what a crappy speaker phone’s echo sounds like and I am not at all concerned about that. Crappy speaker phones sound like crappy speaker phones no matter what. I don’t think that’s what I am trying to track down. These are business call where 90% are using the standard handset on business quality phones. It happens at various levels, but when it is at the bad end of the spectrum (e.g. long delay and loud), it does not sound like echo off of walls coming back in a microphone. It is like my input channel has been delayed, softened and looped directly back to me crystal clear. Maybe it is one of my VOIP providers’ hardware or software and is load dependent, but the problem exists outside of cheap phones. And of course it is only reproducible on 3 calls in a hundred at peak usage hours, making it a nightmare to track or diagnose. But those 3 calls are the ones my customers want to talk about at billing time.****
** **
Now, I have just thrown that all out there is hopes that 50 people will say “That absolutely never happens to me with FS” so I can look at it a different way.****
** **
Thanks for your thoughts.****
Sean****
** **
*From:* freeswitch-users-bounces@lists.freeswitch.org [mailto: freeswitch-users-bounces@lists.freeswitch.org] *On Behalf Of *Anthony Minessale *Sent:* Monday, March 18, 2013 7:30 PM
*To:* FreeSWITCH Users Help *Subject:* Re: [Freeswitch-users] Removing echo.****
** **
The best place for echo cancelation is in the clients as close to the mic as possible.****
Someone asked why skype and some apps are better. It's because they have echo cans in the client app.****
Sip soft phones are basically toys unless they have some kind of advanced gain and echo controls on your pc because that is where your mic is and could have the vol turned up too high etc.****
** **
From FS perspective in the middle, we can't tell its echo or not because we are just passing the data along and we're typically getting it 30-70 ms too late. ****
** **
** **
In general, you don't get echo when using real phones because they have proper hardware and software to deal with the place where the audio is being sampled and rendered.****
** **
** **
** **
** **
** **
On Mon, Mar 18, 2013 at 5:15 PM, Christopher Rienzo <cmrienzo@gmail.com> wrote:****
Echo cancellation is not easy. The only open source one I've seen is GPL (making it license incompatible with FreeSWITCH) and is not suitable for handling echo over IP networks. Perhaps tricks are being played using VAD to only allow only one speaker at a time in the ooVoo conference?****
****
On Mon, Mar 18, 2013 at 5:53 PM, Mimiko <vbvbrj@gmail.com> wrote:****
Today we tried ooVoo conference system with theirs client using same boxes and microphones - again, no echo. How this can be? Is it only commercial products have echo removing function?****
-- Mimiko desu.
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org****
** **
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org****
****
** **
-- Anthony Minessale II
FreeSWITCH http://www.freeswitch.org/ ClueCon http://www.cluecon.com/ Twitter: http://twitter.com/FreeSWITCH_wire
AIM: anthm MSN:anthony_minessale@hotmail.com GTALK/JABBER/PAYPAL:anthony.minessale@gmail.com IRC: irc.freenode.net #freeswitch
FreeSWITCH Developer Conference sip:888@conference.freeswitch.org googletalk:conf+888@conference.freeswitch.org pstn:+19193869900 ****
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
-- Anthony Minessale II FreeSWITCH http://www.freeswitch.org/ ClueCon http://www.cluecon.com/ Twitter: http://twitter.com/FreeSWITCH_wire AIM: anthm MSN:anthony_minessale@hotmail.com GTALK/JABBER/PAYPAL:anthony.minessale@gmail.com IRC: irc.freenode.net #freeswitch FreeSWITCH Developer Conference sip:888@conference.freeswitch.org googletalk:conf+888@conference.freeswitch.org pstn:+19193869900
Hi Sean, We were experiencing a similar problem with these units and were able to verify that it was in fact the remote end but the threshold of the echo canceler seems to be too low by default. We could hear echo and then unplug the handset from the base on the other end, without muting, and the echo would stop. We found that decreasing the gain slightly all but eliminated complaints. This does reduce the level slightly but in our traces it was close to on par with an analog handset. The pertinent configuration options are: <Handset_Input_Gain>-6</Handset_Input_Gain> <Headset_Input_Gain>-6</Headset_Input_Gain> <Speakerphone_Input_Gain>-6</Speakerphone_Input_Gain> <Handset_Additional_Input_Gain>0</Handset_Additional_Input_Gain> <Headset_Additional_Input_Gain>0</Headset_Additional_Input_Gain> <Speakerphone_Additional_Input_Gain>0</Speakerphone_Additional_Input_Gain> Thanks, Spencer On Mar 19, 2013, at 7:49 AM, Anthony Minessale wrote:
Sean,
You are welcome to disagree. Science is driven by people being unwilling to accept things as they are. I do have some explanations for you if you are interested.
Cisco and Linksys ATA both have echo cancelers in them at the point where the analog data is converted to digital. This is the ideal place for it as I mentioned earlier. So they actually are doing something about the problem and that is why you do not observe one. Getting echo while using a cell phone is also very common. The more latency and conversion of the audio data you experience, the more likely you can have echo. (iPhone is notorious) The other place where its important to have echo cancellation is the point where the digital data in the rtp stream is transferred into the TDM gateway interfacing with the PSTN. This is why most TDM cards like Digium and Sangoma have onboard echo canceler chips. We are not completely helpless, we can do some unnatural things like decode the audio signal we are passing through and try to run some echo cancellation on it but, in the conditions you describe where you hear a perfect replica of what you are saying 2-5 seconds later only softer. That is for sure outside the range of any echo canceler. It cannot reliably tell that this clean signal coming many seconds later should be filtered out because its a replica of data that has already passed by long before. Usually in this type of issue, you are actually hearing the other side hear what you said. So you say the statement, the latency takes its toll and the echo is coming back at you from the far end as they are hearing it.
I am open to options. We do have some work on doing some inline audio processing underway but we should not rely on them if we can possibly control the surroundings better first. If you are talking to me in the same room using a megaphone and I am wearing ear plugs. Its easier to tell you to turn off the megaphone and tell me to remove the ear plugs.
On Mon, Mar 18, 2013 at 9:24 PM, Sean Devoy <sdevoy@bizfocused.com> wrote: Hey Anthony,
Does that mean PBXMate is not worth investigating?
I have to disagree here. Placing the blame entirely on the phones at the other end doesn’t hold water for me. I have had echo problems calling from my cell phone when leaving a voice mail on FS where there is no phone at the other end. So clearly there are situations where it ain’t just the phone at the other end. It also leaves no explanation why Cisco Phones and Linksys ATAs don’t have the same problem with Commercial Venders like Vonage. They don’t have anything different at the end of the line for echo cancellation then FS does. I have also had users confirm they are still getting echo with the microphone MUTED on my end.
Again, I love FS and I am not trying to bash anyone or any code. I am just saying there has to be more to this puzzle. I know what a crappy speaker phone’s echo sounds like and I am not at all concerned about that. Crappy speaker phones sound like crappy speaker phones no matter what. I don’t think that’s what I am trying to track down. These are business call where 90% are using the standard handset on business quality phones. It happens at various levels, but when it is at the bad end of the spectrum (e.g. long delay and loud), it does not sound like echo off of walls coming back in a microphone. It is like my input channel has been delayed, softened and looped directly back to me crystal clear. Maybe it is one of my VOIP providers’ hardware or software and is load dependent, but the problem exists outside of cheap phones. And of course it is only reproducible on 3 calls in a hundred at peak usage hours, making it a nightmare to track or diagnose. But those 3 calls are the ones my customers want to talk about at billing time.
Now, I have just thrown that all out there is hopes that 50 people will say “That absolutely never happens to me with FS” so I can look at it a different way.
Thanks for your thoughts.
Sean
From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Anthony Minessale Sent: Monday, March 18, 2013 7:30 PM
To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Removing echo.
The best place for echo cancelation is in the clients as close to the mic as possible.
Someone asked why skype and some apps are better. It's because they have echo cans in the client app.
Sip soft phones are basically toys unless they have some kind of advanced gain and echo controls on your pc because that is where your mic is and could have the vol turned up too high etc.
From FS perspective in the middle, we can't tell its echo or not because we are just passing the data along and we're typically getting it 30-70 ms too late.
In general, you don't get echo when using real phones because they have proper hardware and software to deal with the place where the audio is being sampled and rendered.
On Mon, Mar 18, 2013 at 5:15 PM, Christopher Rienzo <cmrienzo@gmail.com> wrote:
Echo cancellation is not easy. The only open source one I've seen is GPL (making it license incompatible with FreeSWITCH) and is not suitable for handling echo over IP networks. Perhaps tricks are being played using VAD to only allow only one speaker at a time in the ooVoo conference?
On Mon, Mar 18, 2013 at 5:53 PM, Mimiko <vbvbrj@gmail.com> wrote:
Today we tried ooVoo conference system with theirs client using same boxes and microphones - again, no echo. How this can be? Is it only commercial products have echo removing function?
-- Mimiko desu.
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
-- Anthony Minessale II
FreeSWITCH http://www.freeswitch.org/ ClueCon http://www.cluecon.com/ Twitter: http://twitter.com/FreeSWITCH_wire
AIM: anthm MSN:anthony_minessale@hotmail.com GTALK/JABBER/PAYPAL:anthony.minessale@gmail.com IRC: irc.freenode.net #freeswitch
FreeSWITCH Developer Conference sip:888@conference.freeswitch.org googletalk:conf+888@conference.freeswitch.org pstn:+19193869900
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
-- Anthony Minessale II
FreeSWITCH http://www.freeswitch.org/ ClueCon http://www.cluecon.com/ Twitter: http://twitter.com/FreeSWITCH_wire
AIM: anthm MSN:anthony_minessale@hotmail.com GTALK/JABBER/PAYPAL:anthony.minessale@gmail.com IRC: irc.freenode.net #freeswitch
FreeSWITCH Developer Conference sip:888@conference.freeswitch.org googletalk:conf+888@conference.freeswitch.org pstn:+19193869900 _________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
Anthony and Spencer, Thanks for your responses. Anthony the megaphone analogy really worked for me. Spencer thanks for saving me the time of looking up those settings. I agree cell phones frequently have huge echo. The longer the echo delay (aka higher latency) the harder it is to correct makes perfect sense as well. I actually had a chance to talk to one of the users experiencing this problem. Bear in mind I usually get to talk to her boss who is looking for reasons to not pay his bill. She said they do still "occasionally" get echo but it is not too bad. She said it is always worse when the call certain people (that correlate's with end user device problems). Then she mentioned I was one of the ones they usually get echo with and it was happening now, but not that bad! Opportunity knocked, so I jumped in! First a quick note of reference - I have moderately high hearing loss and wear hearing aids. I keep my headset turned up fairly high! I asked the user who called me to talk to herself while I did some tests and tell me if the echo got better or even went away. Low and Behold - mute made it go away COMPLETELY. As much as I hate it when Anthony is right, it is hard to deny it. I tested further and each of these things helped enough that she noticed: Turning my headset speaker down on the inline volume control, turning the headset speaker down at the phone, turning my microphone boost down (this headset has 3 settings for microphone level), muting at the phone or on the inline headset control. All of those things taken collectively say "Listen to Anthony butthead." So, assuming the cause of the echo is beyond my control (e.g. someone else's phone) are we just screwed or is it just cost prohibitive? I would rather reply that it would cost $5000 to fix it than say "can't be helped." Suppose the user detects bad echo. Is there anything we could do (assuming they could notify FS through a programmable key or even web link, etc)? Could we drop the gain to and from the remote end? I promise to let this die now. Let me here your final thoughts. Thanks again for your time and patience. From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Spencer Thomason Sent: Tuesday, March 19, 2013 11:40 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Removing echo. Hi Sean, We were experiencing a similar problem with these units and were able to verify that it was in fact the remote end but the threshold of the echo canceler seems to be too low by default. We could hear echo and then unplug the handset from the base on the other end, without muting, and the echo would stop. We found that decreasing the gain slightly all but eliminated complaints. This does reduce the level slightly but in our traces it was close to on par with an analog handset. The pertinent configuration options are: <Handset_Input_Gain>-6</Handset_Input_Gain> <Headset_Input_Gain>-6</Headset_Input_Gain> <Speakerphone_Input_Gain>-6</Speakerphone_Input_Gain> <Handset_Additional_Input_Gain>0</Handset_Additional_Input_Gain> <Headset_Additional_Input_Gain>0</Headset_Additional_Input_Gain> <Speakerphone_Additional_Input_Gain>0</Speakerphone_Additional_Input_Gain> Thanks, Spencer On Mar 19, 2013, at 7:49 AM, Anthony Minessale wrote: Sean, You are welcome to disagree. Science is driven by people being unwilling to accept things as they are. I do have some explanations for you if you are interested. Cisco and Linksys ATA both have echo cancelers in them at the point where the analog data is converted to digital. This is the ideal place for it as I mentioned earlier. So they actually are doing something about the problem and that is why you do not observe one. Getting echo while using a cell phone is also very common. The more latency and conversion of the audio data you experience, the more likely you can have echo. (iPhone is notorious) The other place where its important to have echo cancellation is the point where the digital data in the rtp stream is transferred into the TDM gateway interfacing with the PSTN. This is why most TDM cards like Digium and Sangoma have onboard echo canceler chips. We are not completely helpless, we can do some unnatural things like decode the audio signal we are passing through and try to run some echo cancellation on it but, in the conditions you describe where you hear a perfect replica of what you are saying 2-5 seconds later only softer. That is for sure outside the range of any echo canceler. It cannot reliably tell that this clean signal coming many seconds later should be filtered out because its a replica of data that has already passed by long before. Usually in this type of issue, you are actually hearing the other side hear what you said. So you say the statement, the latency takes its toll and the echo is coming back at you from the far end as they are hearing it. I am open to options. We do have some work on doing some inline audio processing underway but we should not rely on them if we can possibly control the surroundings better first. If you are talking to me in the same room using a megaphone and I am wearing ear plugs. Its easier to tell you to turn off the megaphone and tell me to remove the ear plugs. On Mon, Mar 18, 2013 at 9:24 PM, Sean Devoy <sdevoy@bizfocused.com> wrote: Hey Anthony, Does that mean PBXMate is not worth investigating? I have to disagree here. Placing the blame entirely on the phones at the other end doesn't hold water for me. I have had echo problems calling from my cell phone when leaving a voice mail on FS where there is no phone at the other end. So clearly there are situations where it ain't just the phone at the other end. It also leaves no explanation why Cisco Phones and Linksys ATAs don't have the same problem with Commercial Venders like Vonage. They don't have anything different at the end of the line for echo cancellation then FS does. I have also had users confirm they are still getting echo with the microphone MUTED on my end. Again, I love FS and I am not trying to bash anyone or any code. I am just saying there has to be more to this puzzle. I know what a crappy speaker phone's echo sounds like and I am not at all concerned about that. Crappy speaker phones sound like crappy speaker phones no matter what. I don't think that's what I am trying to track down. These are business call where 90% are using the standard handset on business quality phones. It happens at various levels, but when it is at the bad end of the spectrum (e.g. long delay and loud), it does not sound like echo off of walls coming back in a microphone. It is like my input channel has been delayed, softened and looped directly back to me crystal clear. Maybe it is one of my VOIP providers' hardware or software and is load dependent, but the problem exists outside of cheap phones. And of course it is only reproducible on 3 calls in a hundred at peak usage hours, making it a nightmare to track or diagnose. But those 3 calls are the ones my customers want to talk about at billing time. Now, I have just thrown that all out there is hopes that 50 people will say "That absolutely never happens to me with FS" so I can look at it a different way. Thanks for your thoughts. Sean From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Anthony Minessale Sent: Monday, March 18, 2013 7:30 PM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Removing echo. The best place for echo cancelation is in the clients as close to the mic as possible. Someone asked why skype and some apps are better. It's because they have echo cans in the client app. Sip soft phones are basically toys unless they have some kind of advanced gain and echo controls on your pc because that is where your mic is and could have the vol turned up too high etc.
From FS perspective in the middle, we can't tell its echo or not because we are just passing the data along and we're typically getting it 30-70 ms too late.
In general, you don't get echo when using real phones because they have proper hardware and software to deal with the place where the audio is being sampled and rendered. On Mon, Mar 18, 2013 at 5:15 PM, Christopher Rienzo <cmrienzo@gmail.com> wrote: Echo cancellation is not easy. The only open source one I've seen is GPL (making it license incompatible with FreeSWITCH) and is not suitable for handling echo over IP networks. Perhaps tricks are being played using VAD to only allow only one speaker at a time in the ooVoo conference? On Mon, Mar 18, 2013 at 5:53 PM, Mimiko <vbvbrj@gmail.com> wrote: Today we tried ooVoo conference system with theirs client using same boxes and microphones - again, no echo. How this can be? Is it only commercial products have echo removing function? -- Mimiko desu. _________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com <http://www.freeswitchsolutions.com/> FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com <http://www.cudatel.com/> Official FreeSWITCH Sites http://www.freeswitch.org <http://www.freeswitch.org/> http://wiki.freeswitch.org <http://wiki.freeswitch.org/> http://www.cluecon.com <http://www.cluecon.com/> FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org <http://www.freeswitch.org/> _________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com <http://www.freeswitchsolutions.com/> FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com <http://www.cudatel.com/> Official FreeSWITCH Sites http://www.freeswitch.org <http://www.freeswitch.org/> http://wiki.freeswitch.org <http://wiki.freeswitch.org/> http://www.cluecon.com <http://www.cluecon.com/> FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org <http://www.freeswitch.org/> -- Anthony Minessale II FreeSWITCH http://www.freeswitch.org/ ClueCon http://www.cluecon.com/ Twitter: http://twitter.com/FreeSWITCH_wire AIM: anthm MSN:anthony_minessale@hotmail.com <mailto:MSN%3Aanthony_minessale@hotmail.com> GTALK/JABBER/PAYPAL:anthony.minessale@gmail.com <mailto:PAYPAL%3Aanthony.minessale@gmail.com> IRC: irc.freenode.net <http://irc.freenode.net/> #freeswitch FreeSWITCH Developer Conference sip:888@conference.freeswitch.org <mailto:sip%3A888@conference.freeswitch.org> googletalk:conf+888@conference.freeswitch.org <mailto:googletalk%3Aconf%2B888@conference.freeswitch.org> pstn:+19193869900 <tel:%2B19193869900> _________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com <http://www.freeswitchsolutions.com/> FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com <http://www.cudatel.com/> Official FreeSWITCH Sites http://www.freeswitch.org <http://www.freeswitch.org/> http://wiki.freeswitch.org <http://wiki.freeswitch.org/> http://www.cluecon.com <http://www.cluecon.com/> FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org <http://www.freeswitch.org/> -- Anthony Minessale II FreeSWITCH http://www.freeswitch.org/ ClueCon http://www.cluecon.com/ Twitter: http://twitter.com/FreeSWITCH_wire AIM: anthm MSN:anthony_minessale@hotmail.com <mailto:MSN%3Aanthony_minessale@hotmail.com> GTALK/JABBER/PAYPAL:anthony.minessale@gmail.com <mailto:PAYPAL%3Aanthony.minessale@gmail.com> IRC: irc.freenode.net <http://irc.freenode.net/> #freeswitch FreeSWITCH Developer Conference sip:888@conference.freeswitch.org <mailto:sip%3A888@conference.freeswitch.org> googletalk:conf+888@conference.freeswitch.org <mailto:googletalk%3Aconf%2B888@conference.freeswitch.org> pstn:+19193869900 _________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
Before the thread dies I would like to add to this subject that there is an Open Source echo canceler exists: Oslec As written on their site it already works with "*You*-*Know-Who*"... :) Has anyone seriously considered integrating it into FreeSWITCH? 2013/3/19 Sean Devoy <sdevoy@bizfocused.com>
Anthony and Spencer,****
** **
Thanks for your responses. Anthony the megaphone analogy really worked for me. Spencer thanks for saving me the time of looking up those settings.** **
** **
I agree cell phones frequently have huge echo. The longer the echo delay (aka higher latency) the harder it is to correct makes perfect sense as well.****
** **
I actually had a chance to talk to one of the users experiencing this problem. Bear in mind I usually get to talk to her boss who is looking for reasons to not pay his bill. She said they do still “occasionally” get echo but it is not too bad. She said it is always worse when the call certain people (that correlate’s with end user device problems). Then she mentioned I was one of the ones they usually get echo with and it was happening now, but not that bad!****
** **
Opportunity knocked, so I jumped in! First a quick note of reference – I have moderately high hearing loss and wear hearing aids. I keep my headset turned up fairly high! I asked the user who called me to talk to herself while I did some tests and tell me if the echo got better or even went away. Low and Behold – mute made it go away COMPLETELY. As much as I hate it when Anthony is right, it is hard to deny it. I tested further and each of these things helped enough that she noticed: Turning my headset speaker down on the inline volume control, turning the headset speaker down at the phone, turning my microphone boost down (this headset has 3 settings for microphone level), muting at the phone or on the inline headset control. All of those things taken collectively say “Listen to Anthony butthead.”** **
** **
So, assuming the cause of the echo is beyond my control (e.g. someone else’s phone) are we just screwed or is it just cost prohibitive? I would rather reply that it would cost $5000 to fix it than say “can’t be helped.” ****
** **
Suppose the user detects bad echo. Is there anything we could do (assuming they could notify FS through a programmable key or even web link, etc)? Could we drop the gain to and from the remote end?****
** **
I promise to let this die now. Let me here your final thoughts.****
** **
Thanks again for your time and patience.****
** **
*From:* freeswitch-users-bounces@lists.freeswitch.org [mailto: freeswitch-users-bounces@lists.freeswitch.org] *On Behalf Of *Spencer Thomason *Sent:* Tuesday, March 19, 2013 11:40 AM
*To:* FreeSWITCH Users Help *Subject:* Re: [Freeswitch-users] Removing echo.****
** **
Hi Sean,****
We were experiencing a similar problem with these units and were able to verify that it was in fact the remote end but the threshold of the echo canceler seems to be too low by default. We could hear echo and then unplug the handset from the base on the other end, without muting, and the echo would stop. We found that decreasing the gain slightly all but eliminated complaints. This does reduce the level slightly but in our traces it was close to on par with an analog handset. The pertinent configuration options are:****
** **
<Handset_Input_Gain>-6</Handset_Input_Gain> <Headset_Input_Gain>-6</Headset_Input_Gain> <Speakerphone_Input_Gain>-6</Speakerphone_Input_Gain> <Handset_Additional_Input_Gain>0</Handset_Additional_Input_Gain> <Headset_Additional_Input_Gain>0</Headset_Additional_Input_Gain>
<Speakerphone_Additional_Input_Gain>0</Speakerphone_Additional_Input_Gain> ****
** **
Thanks,****
Spencer****
** **
** **
On Mar 19, 2013, at 7:49 AM, Anthony Minessale wrote:****
****
Sean,****
** **
You are welcome to disagree. Science is driven by people being unwilling to accept things as they are.****
I do have some explanations for you if you are interested.****
** **
Cisco and Linksys ATA both have echo cancelers in them at the point where the analog data is converted to digital. This is the ideal place for it as I mentioned earlier. So they actually are doing something about the problem and that is why you do not observe one. Getting echo while using a cell phone is also very common. The more latency and conversion of the audio data you experience, the more likely you can have echo. (iPhone is notorious) The other place where its important to have echo cancellation is the point where the digital data in the rtp stream is transferred into the TDM gateway interfacing with the PSTN. This is why most TDM cards like Digium and Sangoma have onboard echo canceler chips. We are not completely helpless, we can do some unnatural things like decode the audio signal we are passing through and try to run some echo cancellation on it but, in the conditions you describe where you hear a perfect replica of what you are saying 2-5 seconds later only softer. That is for sure outside the range of any echo canceler. It cannot reliably tell that this clean signal coming many seconds later should be filtered out because its a replica of data that has already passed by long before. Usually in this type of issue, you are actually hearing the other side hear what you said. So you say the statement, the latency takes its toll and the echo is coming back at you from the far end as they are hearing it. ****
** **
I am open to options. We do have some work on doing some inline audio processing underway but we should not rely on them if we can possibly control the surroundings better first. If you are talking to me in the same room using a megaphone and I am wearing ear plugs. Its easier to tell you to turn off the megaphone and tell me to remove the ear plugs.****
** **
** **
** **
** **
On Mon, Mar 18, 2013 at 9:24 PM, Sean Devoy <sdevoy@bizfocused.com> wrote: ****
Hey Anthony,****
****
Does that mean PBXMate is not worth investigating?****
****
I have to disagree here. Placing the blame entirely on the phones at the other end doesn’t hold water for me. I have had echo problems calling from my cell phone when leaving a voice mail on FS where there is no phone at the other end. So clearly there are situations where it ain’t just the phone at the other end. It also leaves no explanation why Cisco Phones and Linksys ATAs don’t have the same problem with Commercial Venders like Vonage. They don’t have anything different at the end of the line for echo cancellation then FS does. I have also had users confirm they are still getting echo with the microphone MUTED on my end.****
****
Again, I love FS and I am not trying to bash anyone or any code. I am just saying there has to be more to this puzzle. I know what a crappy speaker phone’s echo sounds like and I am not at all concerned about that. Crappy speaker phones sound like crappy speaker phones no matter what. I don’t think that’s what I am trying to track down. These are business call where 90% are using the standard handset on business quality phones. It happens at various levels, but when it is at the bad end of the spectrum (e.g. long delay and loud), it does not sound like echo off of walls coming back in a microphone. It is like my input channel has been delayed, softened and looped directly back to me crystal clear. Maybe it is one of my VOIP providers’ hardware or software and is load dependent, but the problem exists outside of cheap phones. And of course it is only reproducible on 3 calls in a hundred at peak usage hours, making it a nightmare to track or diagnose. But those 3 calls are the ones my customers want to talk about at billing time.****
****
Now, I have just thrown that all out there is hopes that 50 people will say “That absolutely never happens to me with FS” so I can look at it a different way.****
****
Thanks for your thoughts.****
Sean****
****
*From:* freeswitch-users-bounces@lists.freeswitch.org [mailto: freeswitch-users-bounces@lists.freeswitch.org] *On Behalf Of *Anthony Minessale *Sent:* Monday, March 18, 2013 7:30 PM****
*To:* FreeSWITCH Users Help *Subject:* Re: [Freeswitch-users] Removing echo.****
** **
****
The best place for echo cancelation is in the clients as close to the mic as possible.****
Someone asked why skype and some apps are better. It's because they have echo cans in the client app.****
Sip soft phones are basically toys unless they have some kind of advanced gain and echo controls on your pc because that is where your mic is and could have the vol turned up too high etc.****
****
From FS perspective in the middle, we can't tell its echo or not because we are just passing the data along and we're typically getting it 30-70 ms too late. ****
****
****
In general, you don't get echo when using real phones because they have proper hardware and software to deal with the place where the audio is being sampled and rendered.****
****
****
****
****
****
On Mon, Mar 18, 2013 at 5:15 PM, Christopher Rienzo <cmrienzo@gmail.com> wrote:****
Echo cancellation is not easy. The only open source one I've seen is GPL (making it license incompatible with FreeSWITCH) and is not suitable for handling echo over IP networks. Perhaps tricks are being played using VAD to only allow only one speaker at a time in the ooVoo conference?****
** **
On Mon, Mar 18, 2013 at 5:53 PM, Mimiko <vbvbrj@gmail.com> wrote:****
Today we tried ooVoo conference system with theirs client using same boxes and microphones - again, no echo. How this can be? Is it only commercial products have echo removing function?****
-- Mimiko desu.
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org****
****
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org****
****
****
-- Anthony Minessale II
FreeSWITCH http://www.freeswitch.org/ ClueCon http://www.cluecon.com/ Twitter: http://twitter.com/FreeSWITCH_wire
AIM: anthm MSN:anthony_minessale@hotmail.com GTALK/JABBER/PAYPAL:anthony.minessale@gmail.com IRC: irc.freenode.net #freeswitch
FreeSWITCH Developer Conference sip:888@conference.freeswitch.org googletalk:conf+888@conference.freeswitch.org pstn:+19193869900 ****
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org****
****
** **
-- Anthony Minessale II
FreeSWITCH http://www.freeswitch.org/ ClueCon http://www.cluecon.com/ Twitter: http://twitter.com/FreeSWITCH_wire
AIM: anthm MSN:anthony_minessale@hotmail.com GTALK/JABBER/PAYPAL:anthony.minessale@gmail.com IRC: irc.freenode.net #freeswitch
FreeSWITCH Developer Conference sip:888@conference.freeswitch.org googletalk:conf+888@conference.freeswitch.org pstn:+19193869900 ****
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org****
** **
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
2 problems with it. First, it's GPL. Second, it's a line echo canceller. On Tue, Mar 19, 2013 at 2:27 PM, Vitalie Colosov <vetali100@gmail.com>wrote:
Before the thread dies I would like to add to this subject that there is an Open Source echo canceler exists: Oslec As written on their site it already works with "*You*-*Know-Who*"... :) Has anyone seriously considered integrating it into FreeSWITCH?
2013/3/19 Sean Devoy <sdevoy@bizfocused.com>
Anthony and Spencer,****
** **
Thanks for your responses. Anthony the megaphone analogy really worked for me. Spencer thanks for saving me the time of looking up those settings. ****
** **
I agree cell phones frequently have huge echo. The longer the echo delay (aka higher latency) the harder it is to correct makes perfect sense as well.****
** **
I actually had a chance to talk to one of the users experiencing this problem. Bear in mind I usually get to talk to her boss who is looking for reasons to not pay his bill. She said they do still “occasionally” get echo but it is not too bad. She said it is always worse when the call certain people (that correlate’s with end user device problems). Then she mentioned I was one of the ones they usually get echo with and it was happening now, but not that bad!****
** **
Opportunity knocked, so I jumped in! First a quick note of reference – I have moderately high hearing loss and wear hearing aids. I keep my headset turned up fairly high! I asked the user who called me to talk to herself while I did some tests and tell me if the echo got better or even went away. Low and Behold – mute made it go away COMPLETELY. As much as I hate it when Anthony is right, it is hard to deny it. I tested further and each of these things helped enough that she noticed: Turning my headset speaker down on the inline volume control, turning the headset speaker down at the phone, turning my microphone boost down (this headset has 3 settings for microphone level), muting at the phone or on the inline headset control. All of those things taken collectively say “Listen to Anthony butthead.”* ***
** **
So, assuming the cause of the echo is beyond my control (e.g. someone else’s phone) are we just screwed or is it just cost prohibitive? I would rather reply that it would cost $5000 to fix it than say “can’t be helped.” ****
** **
Suppose the user detects bad echo. Is there anything we could do (assuming they could notify FS through a programmable key or even web link, etc)? Could we drop the gain to and from the remote end?****
** **
I promise to let this die now. Let me here your final thoughts.****
** **
Thanks again for your time and patience.****
** **
*From:* freeswitch-users-bounces@lists.freeswitch.org [mailto: freeswitch-users-bounces@lists.freeswitch.org] *On Behalf Of *Spencer Thomason *Sent:* Tuesday, March 19, 2013 11:40 AM
*To:* FreeSWITCH Users Help *Subject:* Re: [Freeswitch-users] Removing echo.****
** **
Hi Sean,****
We were experiencing a similar problem with these units and were able to verify that it was in fact the remote end but the threshold of the echo canceler seems to be too low by default. We could hear echo and then unplug the handset from the base on the other end, without muting, and the echo would stop. We found that decreasing the gain slightly all but eliminated complaints. This does reduce the level slightly but in our traces it was close to on par with an analog handset. The pertinent configuration options are:****
** **
<Handset_Input_Gain>-6</Handset_Input_Gain> <Headset_Input_Gain>-6</Headset_Input_Gain> <Speakerphone_Input_Gain>-6</Speakerphone_Input_Gain> <Handset_Additional_Input_Gain>0</Handset_Additional_Input_Gain> <Headset_Additional_Input_Gain>0</Headset_Additional_Input_Gain>
<Speakerphone_Additional_Input_Gain>0</Speakerphone_Additional_Input_Gain> ****
** **
Thanks,****
Spencer****
** **
** **
On Mar 19, 2013, at 7:49 AM, Anthony Minessale wrote:****
****
Sean,****
** **
You are welcome to disagree. Science is driven by people being unwilling to accept things as they are.****
I do have some explanations for you if you are interested.****
** **
Cisco and Linksys ATA both have echo cancelers in them at the point where the analog data is converted to digital. This is the ideal place for it as I mentioned earlier. So they actually are doing something about the problem and that is why you do not observe one. Getting echo while using a cell phone is also very common. The more latency and conversion of the audio data you experience, the more likely you can have echo. (iPhone is notorious) The other place where its important to have echo cancellation is the point where the digital data in the rtp stream is transferred into the TDM gateway interfacing with the PSTN. This is why most TDM cards like Digium and Sangoma have onboard echo canceler chips. We are not completely helpless, we can do some unnatural things like decode the audio signal we are passing through and try to run some echo cancellation on it but, in the conditions you describe where you hear a perfect replica of what you are saying 2-5 seconds later only softer. That is for sure outside the range of any echo canceler. It cannot reliably tell that this clean signal coming many seconds later should be filtered out because its a replica of data that has already passed by long before. Usually in this type of issue, you are actually hearing the other side hear what you said. So you say the statement, the latency takes its toll and the echo is coming back at you from the far end as they are hearing it. ****
** **
I am open to options. We do have some work on doing some inline audio processing underway but we should not rely on them if we can possibly control the surroundings better first. If you are talking to me in the same room using a megaphone and I am wearing ear plugs. Its easier to tell you to turn off the megaphone and tell me to remove the ear plugs.****
** **
** **
** **
** **
On Mon, Mar 18, 2013 at 9:24 PM, Sean Devoy <sdevoy@bizfocused.com> wrote:****
Hey Anthony,****
****
Does that mean PBXMate is not worth investigating?****
****
I have to disagree here. Placing the blame entirely on the phones at the other end doesn’t hold water for me. I have had echo problems calling from my cell phone when leaving a voice mail on FS where there is no phone at the other end. So clearly there are situations where it ain’t just the phone at the other end. It also leaves no explanation why Cisco Phones and Linksys ATAs don’t have the same problem with Commercial Venders like Vonage. They don’t have anything different at the end of the line for echo cancellation then FS does. I have also had users confirm they are still getting echo with the microphone MUTED on my end.****
****
Again, I love FS and I am not trying to bash anyone or any code. I am just saying there has to be more to this puzzle. I know what a crappy speaker phone’s echo sounds like and I am not at all concerned about that. Crappy speaker phones sound like crappy speaker phones no matter what. I don’t think that’s what I am trying to track down. These are business call where 90% are using the standard handset on business quality phones. It happens at various levels, but when it is at the bad end of the spectrum (e.g. long delay and loud), it does not sound like echo off of walls coming back in a microphone. It is like my input channel has been delayed, softened and looped directly back to me crystal clear. Maybe it is one of my VOIP providers’ hardware or software and is load dependent, but the problem exists outside of cheap phones. And of course it is only reproducible on 3 calls in a hundred at peak usage hours, making it a nightmare to track or diagnose. But those 3 calls are the ones my customers want to talk about at billing time.****
****
Now, I have just thrown that all out there is hopes that 50 people will say “That absolutely never happens to me with FS” so I can look at it a different way.****
****
Thanks for your thoughts.****
Sean****
****
*From:* freeswitch-users-bounces@lists.freeswitch.org [mailto: freeswitch-users-bounces@lists.freeswitch.org] *On Behalf Of *Anthony Minessale *Sent:* Monday, March 18, 2013 7:30 PM****
*To:* FreeSWITCH Users Help *Subject:* Re: [Freeswitch-users] Removing echo.****
** **
****
The best place for echo cancelation is in the clients as close to the mic as possible.****
Someone asked why skype and some apps are better. It's because they have echo cans in the client app.****
Sip soft phones are basically toys unless they have some kind of advanced gain and echo controls on your pc because that is where your mic is and could have the vol turned up too high etc.****
****
From FS perspective in the middle, we can't tell its echo or not because we are just passing the data along and we're typically getting it 30-70 ms too late. ****
****
****
In general, you don't get echo when using real phones because they have proper hardware and software to deal with the place where the audio is being sampled and rendered.****
****
****
****
****
****
On Mon, Mar 18, 2013 at 5:15 PM, Christopher Rienzo <cmrienzo@gmail.com> wrote:****
Echo cancellation is not easy. The only open source one I've seen is GPL (making it license incompatible with FreeSWITCH) and is not suitable for handling echo over IP networks. Perhaps tricks are being played using VAD to only allow only one speaker at a time in the ooVoo conference?****
** **
On Mon, Mar 18, 2013 at 5:53 PM, Mimiko <vbvbrj@gmail.com> wrote:****
Today we tried ooVoo conference system with theirs client using same boxes and microphones - again, no echo. How this can be? Is it only commercial products have echo removing function?****
-- Mimiko desu.
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org****
****
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org****
****
****
-- Anthony Minessale II
FreeSWITCH http://www.freeswitch.org/ ClueCon http://www.cluecon.com/ Twitter: http://twitter.com/FreeSWITCH_wire
AIM: anthm MSN:anthony_minessale@hotmail.com GTALK/JABBER/PAYPAL:anthony.minessale@gmail.com IRC: irc.freenode.net #freeswitch
FreeSWITCH Developer Conference sip:888@conference.freeswitch.org googletalk:conf+888@conference.freeswitch.org pstn:+19193869900 ****
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org****
****
** **
-- Anthony Minessale II
FreeSWITCH http://www.freeswitch.org/ ClueCon http://www.cluecon.com/ Twitter: http://twitter.com/FreeSWITCH_wire
AIM: anthm MSN:anthony_minessale@hotmail.com GTALK/JABBER/PAYPAL:anthony.minessale@gmail.com IRC: irc.freenode.net #freeswitch
FreeSWITCH Developer Conference sip:888@conference.freeswitch.org googletalk:conf+888@conference.freeswitch.org pstn:+19193869900 ****
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org****
** **
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
I think its a kernel mod no? So its irrelevant about the license. People use it with FS today but only with Dhadi which is the one place its easy to install. We do have some DSP code in the new webrtc repo in addition to all of Steve's spandsp code. Its not hard to add some audio tuning code its just hard to make sure its effective from a server perspective. It for sure a good idea to add it to mod_portaudio for instance. On Tue, Mar 19, 2013 at 1:27 PM, Vitalie Colosov <vetali100@gmail.com>wrote:
Before the thread dies I would like to add to this subject that there is an Open Source echo canceler exists: Oslec As written on their site it already works with "*You*-*Know-Who*"... :) Has anyone seriously considered integrating it into FreeSWITCH?
2013/3/19 Sean Devoy <sdevoy@bizfocused.com>
Anthony and Spencer,****
** **
Thanks for your responses. Anthony the megaphone analogy really worked for me. Spencer thanks for saving me the time of looking up those settings. ****
** **
I agree cell phones frequently have huge echo. The longer the echo delay (aka higher latency) the harder it is to correct makes perfect sense as well.****
** **
I actually had a chance to talk to one of the users experiencing this problem. Bear in mind I usually get to talk to her boss who is looking for reasons to not pay his bill. She said they do still “occasionally” get echo but it is not too bad. She said it is always worse when the call certain people (that correlate’s with end user device problems). Then she mentioned I was one of the ones they usually get echo with and it was happening now, but not that bad!****
** **
Opportunity knocked, so I jumped in! First a quick note of reference – I have moderately high hearing loss and wear hearing aids. I keep my headset turned up fairly high! I asked the user who called me to talk to herself while I did some tests and tell me if the echo got better or even went away. Low and Behold – mute made it go away COMPLETELY. As much as I hate it when Anthony is right, it is hard to deny it. I tested further and each of these things helped enough that she noticed: Turning my headset speaker down on the inline volume control, turning the headset speaker down at the phone, turning my microphone boost down (this headset has 3 settings for microphone level), muting at the phone or on the inline headset control. All of those things taken collectively say “Listen to Anthony butthead.”* ***
** **
So, assuming the cause of the echo is beyond my control (e.g. someone else’s phone) are we just screwed or is it just cost prohibitive? I would rather reply that it would cost $5000 to fix it than say “can’t be helped.” ****
** **
Suppose the user detects bad echo. Is there anything we could do (assuming they could notify FS through a programmable key or even web link, etc)? Could we drop the gain to and from the remote end?****
** **
I promise to let this die now. Let me here your final thoughts.****
** **
Thanks again for your time and patience.****
** **
*From:* freeswitch-users-bounces@lists.freeswitch.org [mailto: freeswitch-users-bounces@lists.freeswitch.org] *On Behalf Of *Spencer Thomason *Sent:* Tuesday, March 19, 2013 11:40 AM
*To:* FreeSWITCH Users Help *Subject:* Re: [Freeswitch-users] Removing echo.****
** **
Hi Sean,****
We were experiencing a similar problem with these units and were able to verify that it was in fact the remote end but the threshold of the echo canceler seems to be too low by default. We could hear echo and then unplug the handset from the base on the other end, without muting, and the echo would stop. We found that decreasing the gain slightly all but eliminated complaints. This does reduce the level slightly but in our traces it was close to on par with an analog handset. The pertinent configuration options are:****
** **
<Handset_Input_Gain>-6</Handset_Input_Gain> <Headset_Input_Gain>-6</Headset_Input_Gain> <Speakerphone_Input_Gain>-6</Speakerphone_Input_Gain> <Handset_Additional_Input_Gain>0</Handset_Additional_Input_Gain> <Headset_Additional_Input_Gain>0</Headset_Additional_Input_Gain>
<Speakerphone_Additional_Input_Gain>0</Speakerphone_Additional_Input_Gain> ****
** **
Thanks,****
Spencer****
** **
** **
On Mar 19, 2013, at 7:49 AM, Anthony Minessale wrote:****
****
Sean,****
** **
You are welcome to disagree. Science is driven by people being unwilling to accept things as they are.****
I do have some explanations for you if you are interested.****
** **
Cisco and Linksys ATA both have echo cancelers in them at the point where the analog data is converted to digital. This is the ideal place for it as I mentioned earlier. So they actually are doing something about the problem and that is why you do not observe one. Getting echo while using a cell phone is also very common. The more latency and conversion of the audio data you experience, the more likely you can have echo. (iPhone is notorious) The other place where its important to have echo cancellation is the point where the digital data in the rtp stream is transferred into the TDM gateway interfacing with the PSTN. This is why most TDM cards like Digium and Sangoma have onboard echo canceler chips. We are not completely helpless, we can do some unnatural things like decode the audio signal we are passing through and try to run some echo cancellation on it but, in the conditions you describe where you hear a perfect replica of what you are saying 2-5 seconds later only softer. That is for sure outside the range of any echo canceler. It cannot reliably tell that this clean signal coming many seconds later should be filtered out because its a replica of data that has already passed by long before. Usually in this type of issue, you are actually hearing the other side hear what you said. So you say the statement, the latency takes its toll and the echo is coming back at you from the far end as they are hearing it. ****
** **
I am open to options. We do have some work on doing some inline audio processing underway but we should not rely on them if we can possibly control the surroundings better first. If you are talking to me in the same room using a megaphone and I am wearing ear plugs. Its easier to tell you to turn off the megaphone and tell me to remove the ear plugs.****
** **
** **
** **
** **
On Mon, Mar 18, 2013 at 9:24 PM, Sean Devoy <sdevoy@bizfocused.com> wrote:****
Hey Anthony,****
****
Does that mean PBXMate is not worth investigating?****
****
I have to disagree here. Placing the blame entirely on the phones at the other end doesn’t hold water for me. I have had echo problems calling from my cell phone when leaving a voice mail on FS where there is no phone at the other end. So clearly there are situations where it ain’t just the phone at the other end. It also leaves no explanation why Cisco Phones and Linksys ATAs don’t have the same problem with Commercial Venders like Vonage. They don’t have anything different at the end of the line for echo cancellation then FS does. I have also had users confirm they are still getting echo with the microphone MUTED on my end.****
****
Again, I love FS and I am not trying to bash anyone or any code. I am just saying there has to be more to this puzzle. I know what a crappy speaker phone’s echo sounds like and I am not at all concerned about that. Crappy speaker phones sound like crappy speaker phones no matter what. I don’t think that’s what I am trying to track down. These are business call where 90% are using the standard handset on business quality phones. It happens at various levels, but when it is at the bad end of the spectrum (e.g. long delay and loud), it does not sound like echo off of walls coming back in a microphone. It is like my input channel has been delayed, softened and looped directly back to me crystal clear. Maybe it is one of my VOIP providers’ hardware or software and is load dependent, but the problem exists outside of cheap phones. And of course it is only reproducible on 3 calls in a hundred at peak usage hours, making it a nightmare to track or diagnose. But those 3 calls are the ones my customers want to talk about at billing time.****
****
Now, I have just thrown that all out there is hopes that 50 people will say “That absolutely never happens to me with FS” so I can look at it a different way.****
****
Thanks for your thoughts.****
Sean****
****
*From:* freeswitch-users-bounces@lists.freeswitch.org [mailto: freeswitch-users-bounces@lists.freeswitch.org] *On Behalf Of *Anthony Minessale *Sent:* Monday, March 18, 2013 7:30 PM****
*To:* FreeSWITCH Users Help *Subject:* Re: [Freeswitch-users] Removing echo.****
** **
****
The best place for echo cancelation is in the clients as close to the mic as possible.****
Someone asked why skype and some apps are better. It's because they have echo cans in the client app.****
Sip soft phones are basically toys unless they have some kind of advanced gain and echo controls on your pc because that is where your mic is and could have the vol turned up too high etc.****
****
From FS perspective in the middle, we can't tell its echo or not because we are just passing the data along and we're typically getting it 30-70 ms too late. ****
****
****
In general, you don't get echo when using real phones because they have proper hardware and software to deal with the place where the audio is being sampled and rendered.****
****
****
****
****
****
On Mon, Mar 18, 2013 at 5:15 PM, Christopher Rienzo <cmrienzo@gmail.com> wrote:****
Echo cancellation is not easy. The only open source one I've seen is GPL (making it license incompatible with FreeSWITCH) and is not suitable for handling echo over IP networks. Perhaps tricks are being played using VAD to only allow only one speaker at a time in the ooVoo conference?****
** **
On Mon, Mar 18, 2013 at 5:53 PM, Mimiko <vbvbrj@gmail.com> wrote:****
Today we tried ooVoo conference system with theirs client using same boxes and microphones - again, no echo. How this can be? Is it only commercial products have echo removing function?****
-- Mimiko desu.
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org****
****
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org****
****
****
-- Anthony Minessale II
FreeSWITCH http://www.freeswitch.org/ ClueCon http://www.cluecon.com/ Twitter: http://twitter.com/FreeSWITCH_wire
AIM: anthm MSN:anthony_minessale@hotmail.com GTALK/JABBER/PAYPAL:anthony.minessale@gmail.com IRC: irc.freenode.net #freeswitch
FreeSWITCH Developer Conference sip:888@conference.freeswitch.org googletalk:conf+888@conference.freeswitch.org pstn:+19193869900 ****
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org****
****
** **
-- Anthony Minessale II
FreeSWITCH http://www.freeswitch.org/ ClueCon http://www.cluecon.com/ Twitter: http://twitter.com/FreeSWITCH_wire
AIM: anthm MSN:anthony_minessale@hotmail.com GTALK/JABBER/PAYPAL:anthony.minessale@gmail.com IRC: irc.freenode.net #freeswitch
FreeSWITCH Developer Conference sip:888@conference.freeswitch.org googletalk:conf+888@conference.freeswitch.org pstn:+19193869900 ****
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org****
** **
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
FreeSWITCH-powered IP PBX: The CudaTel Communication Server http://www.cudatel.com
Official FreeSWITCH Sites http://www.freeswitch.org http://wiki.freeswitch.org http://www.cluecon.com
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
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This has already been covered in this thread. No it will not be integrated with FreeSWITCH. Oslec is GPL¹d and can not be integrated with FreeSWITCH due to licensing issues. The GPL is not compatible with the MPL1.1. On 3/19/13 12:27 PM, "Vitalie Colosov" <vetali100@gmail.com> wrote:
Before the thread dies I would like to add to this subject that there is an Open Source echo canceler exists: Oslec As written on their site it already works with "You-Know-Who"... :) Has anyone seriously considered integrating it into FreeSWITCH?
2013/3/19 Sean Devoy <sdevoy@bizfocused.com>
Anthony and Spencer, Thanks for your responses. Anthony the megaphone analogy really worked for me. Spencer thanks for saving me the time of looking up those settings. I agree cell phones frequently have huge echo. The longer the echo delay (aka higher latency) the harder it is to correct makes perfect sense as well. I actually had a chance to talk to one of the users experiencing this problem. Bear in mind I usually get to talk to her boss who is looking for reasons to not pay his bill. She said they do still ³occasionally² get echo but it is not too bad. She said it is always worse when the call certain people (that correlate¹s with end user device problems). Then she mentioned I was one of the ones they usually get echo with and it was happening now, but not that bad! Opportunity knocked, so I jumped in! First a quick note of reference I have moderately high hearing loss and wear hearing aids. I keep my headset turned up fairly high! I asked the user who called me to talk to herself while I did some tests and tell me if the echo got better or even went away. Low and Behold mute made it go away COMPLETELY. As much as I hate it when Anthony is right, it is hard to deny it. I tested further and each of these things helped enough that she noticed: Turning my headset speaker down on the inline volume control, turning the headset speaker down at the phone, turning my microphone boost down (this headset has 3 settings for microphone level), muting at the phone or on the inline headset control. All of those things taken collectively say ³Listen to Anthony butthead.² So, assuming the cause of the echo is beyond my control (e.g. someone else¹s phone) are we just screwed or is it just cost prohibitive? I would rather reply that it would cost $5000 to fix it than say ³can¹t be helped.² Suppose the user detects bad echo. Is there anything we could do (assuming they could notify FS through a programmable key or even web link, etc)? Could we drop the gain to and from the remote end? I promise to let this die now. Let me here your final thoughts. Thanks again for your time and patience.
From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Spencer Thomason Sent: Tuesday, March 19, 2013 11:40 AM
To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Removing echo. Hi Sean,
We were experiencing a similar problem with these units and were able to verify that it was in fact the remote end but the threshold of the echo canceler seems to be too low by default. We could hear echo and then unplug the handset from the base on the other end, without muting, and the echo would stop. We found that decreasing the gain slightly all but eliminated complaints. This does reduce the level slightly but in our traces it was close to on par with an analog handset. The pertinent configuration options are:
<Handset_Input_Gain>-6</Handset_Input_Gain> <Headset_Input_Gain>-6</Headset_Input_Gain> <Speakerphone_Input_Gain>-6</Speakerphone_Input_Gain> <Handset_Additional_Input_Gain>0</Handset_Additional_Input_Gain> <Headset_Additional_Input_Gain>0</Headset_Additional_Input_Gain> <Speakerphone_Additional_Input_Gain>0</Speakerphone_Additional_Input_Gain>
Thanks,
Spencer
On Mar 19, 2013, at 7:49 AM, Anthony Minessale wrote:
Sean,
You are welcome to disagree. Science is driven by people being unwilling to accept things as they are.
I do have some explanations for you if you are interested.
Cisco and Linksys ATA both have echo cancelers in them at the point where the analog data is converted to digital. This is the ideal place for it as I mentioned earlier. So they actually are doing something about the problem and that is why you do not observe one. Getting echo while using a cell phone is also very common. The more latency and conversion of the audio data you experience, the more likely you can have echo. (iPhone is notorious) The other place where its important to have echo cancellation is the point where the digital data in the rtp stream is transferred into the TDM gateway interfacing with the PSTN. This is why most TDM cards like Digium and Sangoma have onboard echo canceler chips. We are not completely helpless, we can do some unnatural things like decode the audio signal we are passing through and try to run some echo cancellation on it but, in the conditions you describe where you hear a perfect replica of what you are saying 2-5 seconds later only softer. That is for sure outside the range of any echo canceler. It cannot reliably tell that this clean signal coming many seconds later should be filtered out because its a replica of data that has already passed by long before. Usually in this type of issue, you are actually hearing the other side hear what you said. So you say the statement, the latency takes its toll and the echo is coming back at you from the far end as they are hearing it.
I am open to options. We do have some work on doing some inline audio processing underway but we should not rely on them if we can possibly control the surroundings better first. If you are talking to me in the same room using a megaphone and I am wearing ear plugs. Its easier to tell you to turn off the megaphone and tell me to remove the ear plugs.
On Mon, Mar 18, 2013 at 9:24 PM, Sean Devoy <sdevoy@bizfocused.com> wrote:
Hey Anthony, Does that mean PBXMate is not worth investigating? I have to disagree here. Placing the blame entirely on the phones at the other end doesn¹t hold water for me. I have had echo problems calling from my cell phone when leaving a voice mail on FS where there is no phone at the other end. So clearly there are situations where it ain¹t just the phone at the other end. It also leaves no explanation why Cisco Phones and Linksys ATAs don¹t have the same problem with Commercial Venders like Vonage. They don¹t have anything different at the end of the line for echo cancellation then FS does. I have also had users confirm they are still getting echo with the microphone MUTED on my end. Again, I love FS and I am not trying to bash anyone or any code. I am just saying there has to be more to this puzzle. I know what a crappy speaker phone¹s echo sounds like and I am not at all concerned about that. Crappy speaker phones sound like crappy speaker phones no matter what. I don¹t think that¹s what I am trying to track down. These are business call where 90% are using the standard handset on business quality phones. It happens at various levels, but when it is at the bad end of the spectrum (e.g. long delay and loud), it does not sound like echo off of walls coming back in a microphone. It is like my input channel has been delayed, softened and looped directly back to me crystal clear. Maybe it is one of my VOIP providers¹ hardware or software and is load dependent, but the problem exists outside of cheap phones. And of course it is only reproducible on 3 calls in a hundred at peak usage hours, making it a nightmare to track or diagnose. But those 3 calls are the ones my customers want to talk about at billing time. Now, I have just thrown that all out there is hopes that 50 people will say ³That absolutely never happens to me with FS² so I can look at it a different way. Thanks for your thoughts. Sean From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Anthony Minessale Sent: Monday, March 18, 2013 7:30 PM
To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Removing echo.
The best place for echo cancelation is in the clients as close to the mic as possible.
Someone asked why skype and some apps are better. It's because they have echo cans in the client app.
Sip soft phones are basically toys unless they have some kind of advanced gain and echo controls on your pc because that is where your mic is and could have the vol turned up too high etc.
From FS perspective in the middle, we can't tell its echo or not because we are just passing the data along and we're typically getting it 30-70 ms too late.
In general, you don't get echo when using real phones because they have proper hardware and software to deal with the place where the audio is being sampled and rendered.
On Mon, Mar 18, 2013 at 5:15 PM, Christopher Rienzo <cmrienzo@gmail.com> wrote: Echo cancellation is not easy. The only open source one I've seen is GPL (making it license incompatible with FreeSWITCH) and is not suitable for handling echo over IP networks. Perhaps tricks are being played using VAD to only allow only one speaker at a time in the ooVoo conference?
On Mon, Mar 18, 2013 at 5:53 PM, Mimiko <vbvbrj@gmail.com> wrote: Today we tried ooVoo conference system with theirs client using same boxes and microphones - again, no echo. How this can be? Is it only commercial products have echo removing function?
-- Mimiko desu.
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On 03/20/2013 02:27 AM, Vitalie Colosov wrote:
Before the thread dies I would like to add to this subject that there is an Open Source echo canceler exists: Oslec As written on their site it already works with "/You/-/Know-Who/"... :) Has anyone seriously considered integrating it into FreeSWITCH?
OSLEC does not work with Asterisk. It works with DADHI, the device drivers for telephony cards. If you use DADHI with FreeSwitch, to interface to Digium, Rhino and other makes of card that work with the DADHI drivers, you can use OSLEC. So, OSLEC is exactly as integrated with FreeSwitch as it is with Asterisk. OSLEC is a line echo canceller. It has no place inside a switch. Steve
On 19.03.2013 01:29, Anthony Minessale wrote:
Sip soft phones are basically toys unless they have some kind of advanced gain and echo controls on your pc because that is where your mic is and could have the vol turned up too high etc.
From FS perspective in the middle, we can't tell its echo or not because we are just passing the data along and we're typically getting it 30-70 ms too late.
Anthony. Of course not the server FS or Skype or other is doing echo cancellation. Skype client, for example, has a option to disable echo cancellation in client. On 19.03.2013 02:18, Steve Underwood wrote:> The sad thing is some signal engineers
have approached this from the other end, and built a fairly well engineered soft phone with a very poor UI. People rarely look at those, because they aren't pretty.
That's why I asked about some SIP clients, let them be bad UI, but with echo cancellation. -- Mimiko desu.
On 03/19/2013 05:53 AM, Mimiko wrote:
Today we tried ooVoo conference system with theirs client using same boxes and microphones - again, no echo. How this can be? Is it only commercial products have echo removing function?
If you use a headset for a soft phone you need echo control for really good results. If you use a mic and speaker for a soft phone you need echo control for any kind of usable results. Echo cancellation is a pain to implement on a PC, as the mic and speaker sample rates are not quite identical. That makes the engineering hard, and few people have tackled it. Obviously people like Skype have had to find and pay people who can do the job, or they have no potential to become a large scale enterprise. Most soft phones have been put together by people who thinks they can design a nice UI, and who thinks that is the heart of the problem. Then they discover you need some real engineering to make a good soft phone, and that is beyond them. Thus, we see lots of pretty, but largely useless, open source soft phones. The sad thing is some signal engineers have approached this from the other end, and built a fairly well engineered soft phone with a very poor UI. People rarely look at those, because they aren't pretty. Regards, Steve
participants (14)
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Anthony Minessale
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Christopher Rienzo
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covici＠ccs.covici.com
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Dmitry Lysenko
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Johan Helsingius
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Ken Rice
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Klaus Hochlehnert
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Mimiko
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Sean Devoy
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Spencer Thomason
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Steve Underwood
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Valer Nur
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Vitalie Colosov
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Yossi Neiman