This is the sample app for Noise written in Kotlin with RxJava2. Noise is a Java Android wrapper for kissfft, a FFT implementation written in C.

The FFT:s are rendered from the microphone stream in real time. Expect drag on most devices since the FFT Spectogram rendering isn't that optimal. Works pretty good on modern devices tho.

You can find the source for this app and the lib at the repo https://github.com/paramsen/noise

Code hard,

Pär Amsen