9.10.  Van Gogh (LIC)

[Tip] Tip
  • To create a blur, check With Source Image. Only Filter Length slider and perhaps Integration Steps slider, are useful.

  • To create a texture, check With White Noise. All sliders can be useful.

Convolution

You can use two types of convolution. That's the first parameter you have to set:

  • With White Noise: White Noise is an acoustics name. It's a noise where all frequencies have the same amplitude. Here, this option is used to create patterns.

  • With Source Image: The source image will be blurred.

Effect Image

That's the map for blur or pattern direction. This map must have the same dimensions as the original image. It must be preferably a grayscale image. It must be present on your screen when you call filter so that you can choose it in the drop-list.

Effect Channel

By selecting Hue, Saturation or Brightness (=Value), filter will use this channel to treat image.

Effect Operator

The “Derivative” option reverses “Gradient ” direction:

Filter Length

When applying blur, this option controls how important blur is. When creating a texture, it controls how rough texture is: low values result in smooth surface; high values in rough surface.

Noise Magnitude

This options controls the amount and size of White Noise. Low values produce finely grained surfaces. High values produce coarse-grained textures.

Integration Steps

This options controls the influence of gradient map on texture.

Minimum/Maximum values

Both values determine a range controlling texture contrast: shrunk range results in high contrast and enlarged range results in low contrast.