Oslec, the Open Source Line Echo Canceller: An Interview with David Rowe
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Echo is a pain point in open source telephony. The default echo cancellers provided with Asterisk are generally held to be unacceptable. Hardware add-on modules, the common alternative, add $200 or more to the cost of a voice card and are closed source.
In 2008, David Rowe completed development of an improved software echo canceller: Oslec, the Open Source Line Echo Canceller. Although Oslec has been well reviewed by those who have tested it, the code has not been incorporated into the Asterisk/DAHDI source. Nine years later, I became aware of Oslec while shopping for new voice hardware. David agreed to an email interview for ;login:.
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