Windowing - kosme/arduinoFFT GitHub Wiki
Windowing functions
A windowing function applies a mathematical function to the sampled value in order to give more or less weight to different parts of the signal according to its relative position in the data array.
Functions
Performs a windowing function on the values array. Uses vReal. The possible windowing options are:
- Rectangle
- Hamming
- Hann
- Triangle
- Nuttall
- Blackman
- Blackman_Nuttall
- Blackman_Harris
- Flat_top
- Welch
Compensation
Using a windowing function modifies the data, which reflects attenuates the signal. This attenuation can be compensated to make the computed FFT values more accurate.
If withCompensation
== true, the following compensation factors are used:
- Rectangle: 1.0 * 2.0
- Hamming: 1.8549343278 * 2.0
- Hann: 1.8554726898 * 2.0
- Triangle: 2.0039186079 * 2.0
- Nuttall: 2.8163172034 * 2.0
- Blackman: 2.3673474360 * 2.0
- Blackman Nuttall: 2.7557840395 * 2.0
- Blackman Harris: 2.7929062517 * 2.0
- Flat top: 3.5659039231 * 2.0
- Welch: 1.5029392863 * 2.0