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Software Based Echo Cancellation?

tcyun asks: "I am helping to put together a small studio for a project at my workplace which will require some audio mixing. We have been able to find software solutions (often times open source) for almost all of our needs except for echo cancellation. I have done the requisite searches and have found a large number of hardware based echo cancellation devices, but have not found a purely software based solution. Is anybody aware of one?"

"For some more information, my office is trying to get a small system up and running that will allow multiple locations to video conference together. We have some specific requirements and have a fairly good handle on the entire video part of the problem.

However, we are running into problems with parts of our audio mix. The first issue is something that (I believe) is called 'mix minus.' This means that in a group conference, speakers do not have audio sent back to their location. (This is important for various psychology and network latency related issues.) There are several hardware based solutions that are available and we have some software based options.

The larger problem is echo cancellation. As many people may need to speak at once (and to avoid the requirement of having individuals constantly muting their microphones), we would like an echo cancellation component. The ideal would be a software solution that we could run locally, perhaps in conjunction with the same code running on the remote systems. However, most of the solutions we have found are hardware based (DSPs, ASICs, etc.).

The technology used on the studio side as well as the host side will involve various operating systems. We are trying to avoid avoid relying on specific OTC hardware solutions (namely, sound cards) as we would like to be able to create a solution that would function over time, particularly as specific hardware solutions tend quickly to horizon. So, having nice code that could be compiled on different systems would be a plus. Ideally, we would like to minimize the amount of hardware necessary, so an echo cancellation algorithm that could run in conjunction with other processes would be nice, but it is not a requirement."

4 of 211 comments (clear)

  1. I saw this... by Anonymous Coward · · Score: 0, Offtopic

    On Batman Beyond...

    This scientist had developed an invention that allowed him to block all sound waves, as well as focus their energy. Once he turned evil (and tried to kill Batman), it was a powerful weapon!

    But be careful... if you abuse this sort of weapon, you may end up like him with permanent hearing loss, and a desire for vengrance against Batman.

  2. Re:MeldStar ( MOD DOWN PARENT! ) by wren337 · · Score: 0, Offtopic

    The link to "meldstar" is a redirect to goatse.cx.

    You are a very bad man.

  3. Re:Removing echo by guillebot · · Score: 0, Offtopic

    Clap Clap Clap

  4. Re:how do you do that? by vladkrupin · · Score: 0, Offtopic

    well, it wasn't first post for starters - there were a few before me.

    But it is a really good question why it is redundant.
    I made a statement, I asked a question, no-one agreed/disagreed/answered... Gotta wonder...

    Moderators are interesting people...

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    Jobs? Which jobs?