Acoustic echo cancellation software download
What you hear is the conversation as heard on the N900.Īll this echo cancelling goodness will come to a Linux distribution near you in the upcoming 1.0 release of PulseAudio. The laptop is playing audio out the speakers and recording with the built-in mic. This is a recording of a call between my laptop and N900.
ACOUSTIC ECHO CANCELLATION SOFTWARE DOWNLOAD DOWNLOAD
With AEC: /downloads/pulseaudio/aec/call-with-aec (or download ogg, aac) Without AEC: /downloads/pulseaudio/aec/call-no-aec (or download ogg, aac) While all this sounds nice, I think a demo would sound (haha!) nicer … We also added a bunch of fixes to reduce CPU consumption significantly - this should be good enough to run on a netbook and reasonably recent ARM platforms. Recently, we plugged in some more bits from the Speex library to do noise suppression and digital gain control (so you can quit twiddling with your mic volume for the other end to be able to hear you). The code’s quite modular, so it’s not very hard to plug in alternate echo cancellers (we even include an alternate implementation, which isn’t quite as effective as Speex). We use the Speex DSP library to perform the actual echo cancellation. On Linux, we implement echo cancellation as a PulseAudio module (code-ninja Wim Taymans wrote this last year). On laptops, which are general-purpose hardware, the job of echo cancellation is left to either your operating system (Windows XP onwards, for example) or your chat client (Skype, for example) to provide. That’s because your phone (or, if you have a cheap phone, your phone company) has special software hidden away that removes the echo before sending your signal along to the other end. Astute readers will ask why they don’t actually face this problem on their phone. This problem is common on pretty much all devices that you use to make phone calls. There are other types of echo for phone systems, but that’s not interesting to us at the moment. This is called acoustic echo, and can be frustrating enough to make conversation nigh impossible. When your friend speaks, what she says is played out the speakers, but is also captured by the microphone and she gets to hear herself speak, albeit a short while (a few hundred milliseconds or more) later. You don’t have a pair of headphones lying around, so you’re just going to use your laptop’s built-in speakers and mic. Say you’re on your laptop, and you receive a voice call from your friend. If you already know this, you might want to skip this paragraph and the next. Before too long, all this work will be trickling down to your favourite Linux distribution and all your friends will stop hating you.įirst, a quick recap on what acoustic echo cancellation (AEC) is. Thanks go to Intel for supporting us in continuing this work. Here at Collabora, I’ve been building on Wim’s previous work on adding echo cancellation to PulseAudio.
I can’t say I haven’t enjoyed it - it turns out my capacity to entertain myself is far greater than initially suspected. I’ve spent a great deal of time over the last few months talking to myself.