Open source Speex code contains the VS2003,05,08 project, but the direct compilation there are always some places to set, although it is not very complicated, but for the students who do not know a lot about vs still have to toss a while, so I got a version that can be used directly, of course, compiled with VS2010.
Speex Some aspects are better than WEBRTC, for example, can be directly to the 44.1KHZ sampling rate of audio noise processing, and WEBRTC maximum can only support 32K sampling rate, more than must be resampled to 32K. In addition, the interface is relatively simple, the code is also less. Of course. It also includes echo cancellation, mute detection, sound gain, resampling module, if you want to know the internal principle of the person, you can directly debug artifact VS2010 or even later debug.
Speexdsp-1.2rc3.zip
VS2010 version of the Speex audio processing module (with Source + test demo)