Visualize sound from your Android's microphone.
Technical specification:
Recording
☆ Sample rate: 44100 Mono
☆ Chart buffer: 5 seconds
Decibel Level
☆ Reference pressure p0 = 20uPa
☆ decibel equation: 20 x Log10 (RMS/p0)
Frequency Spectrum
☆ Hanning Window
☆ FFT size: 4410 (100 ms)
☆ Overlapping: 80%
☆ Frequency: 1 Hz ~ 4 KHz over 64 groups
Credits:
☆JTransforms for FFT calculations. https://github.com/wendykierp/JTransforms
Bug Fixes