SciTuner is guitar tuner with real-time signal visualization. The application uses digital signal processing algorithm for accurate frequency estimation and wave visualization. SciTuner presents many useful features:
The previous version of SciTuner 1.1 is available on AppStore. SciTuner 2.0 is coming soon.
The main controller is TunerViewController. This controller works with three models object
Processing receives sound data from
Microphone through controller and calculates power spectrum by
Spectrum is used for estimation greatest peak position in frequency domain. Because a guitar sound may have many harmonics, it's necessary also detect harmonic order. Artificial Neural Network is used for this purposes by activating an input layer with spectrum powers taken on special frequencies (1/4, 1/3, 1/2, 2/3, 3/4, 1, 3/2, 2, 3, 4) relative to greatest peak.
So the result frequency divided by its harmonic order is used for estimation position of a note on the scale with selected pitch and tuning.
This position is showed on display by
Processing allows to take preview data with standing wave effect by phase shifting with value of a greatest frequency peak. This wave is showed by