On Fri, 2011-09-16 at 15:39 +0800, Lin, Mengdong wrote: [...] > So my last question is whether module-echo-cancel can reduce the background noise during recording? If yes, what colors of noise can it reduce? We currently have speex noise suppression enabled by default. You can find some references to the algorithms used at: http://git.xiph.org/?p=speex.git;a=blob;f=libspeex/preprocess.c I've seen it reduce background and fan noise, but I've not got the skillz to understand with the actual method/algorithm myself. -- Arun