How to develop a Spectrum Analyser from a realtime audio?

Question

I am developing an app that get a source audio from mic in realtime, with no file storage. Basically, I use:

mRecorder = new MediaRecorder();
mRecorder.setAu         


        

Answer 1

There is an open source Android spectrum analyzer on Github which computers FFT on audio from the microphone and displays a 2D spectrogram.

The Spectrum Analyzer project is found in the v2.x/Showcase app

You can see a video of it in action at https://youtu.be/yU05fsgOYO4

You can see a video with build instructions here: https://youtu.be/tVgn30uss2k?t=1m37s

The charting is provided by the SciChart Android chart library which is a commercial control, but the source code to read the mic, compute the FFT and spectrogram is free & open source under MIT License.

As a disclosure: I am the tech lead on the SciChart project