This document discusses different digital signal processing distortion techniques including clipping, mirroring, wrapping, tanh distortion, and waveshaping. It provides examples of applying these techniques to sine waves using transfer functions that clip/limit the output signal, reflect it, repeat it, apply a hyperbolic tangent function, or transform it in non-linear ways like with sigmoid or piecewise linear segments. Diagrams and equations are presented to illustrate the different effects on input sine waves.

1. Distortion techniques
Digital Signal Processing
hakon.kvidal@nmh.no

2. Clipping
Sinuskurve
Klipping
Terskel
Thresold

3. Mirror (Speiling)
Sinuskurve
Speiling- Mirror
Terskel
Thresold

4. Wrap (Bretting)
Sinuskurve
Bretting - Wrap
Terskel
Thresold

5. tanh()-funksjonen
• Signalet multipliseres med en hyperbolsk
tangent
A linear transfer
function
(signal unmodified)
tanh(x*2) transfer
function
tanh(x*4) transfer
function

6. tanh()-funksjonen
Sinuskurve
Sine with tanh distortion, gain = 1
Sine with tanh distortion, gain = 3
Sine with tanh distortion, gain = 7

7. Waveshaping

8. Waveshaping – Lytte eks 1
Vi behandler en sinusbølge følgende funksjon
Example transfer function for
waveshaping, rising sigmoid.
Sine waveshaped with
rising sigmoid shaped
transfer function

9. Waveshaping – Lytte eks 2
Vi behandler en sinusbølge følgende funksjon
Example transfer function for
waveshaping, rising sigmoid plus
4th harmonic sine component.
Sine waveshaped with
sigmoid and 4th
harmonic sine transfer
function

10. Waveshaping – Lytte eks 3
Vi behandler en sinusbølge følgende funksjon
Example transfer function for
waveshaping, arbitrary linear
segments.
Sine waveshaped with
arbitrary linear segment
transfer function