Downsampling and applying a lowpass filter to digital audio

Question

I\'ve got a 44Khz audio stream from a CD, represented as an array of 16 bit PCM samples. I\'d like to cut it down to an 11KHz stream. How do I do that? From my days of engine

Answer 1

You could make use of libsamplerate to do the heavy lifting. Libsamplerate is a C API, and takes care of calculating the filter coefficients. You to select from different quality filters so that you can trade off quality for speed.

If you would prefer not to write any code, you could just use Audacity to do the sample rate conversion. It offers a powerful GUI, and makes use of libsamplerate for it's sample rate conversion.