[Speex-dev] Sound card problem in acoustic echo

[limaoquan2000]

Thank you.

But it will cost you a long time to get the accurate play and capture frequencies.
Does your program test two frequencies of the sound card each time? Because
different sound cards have different frequency errors.
And the resampling program is also time consuming because the target frequency is
so close to the sampling frequency of the input signal, isn't it?

I have tested program based on Windows waveform functions and also DirectSound.
They have similar frequency error.

BTW: What's your conclusion of ASIO driver? Why "it was of no practical use"?

> I worked some time for a company doing AEC using Speex on Windows.It is true it depends a lot on sound card models. I remember I could do AEC by resampling frequencies so play and record frequencies where equal.Frequencies where aprox 100Hz appart.Also, I know that on other cases AEC was achieved by disabling FX DirectSound effects where it wasn`t possible before that.Try to disable all you don't need before calling Speex AEC function.
> Also, I tried the ASIO driver,as an experiment. I think it worked, but it was of no practical use.
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