3.4. Selective Gaussian Blur

3.4.1. Overview

Figuur 17.15. The Selective Gaussian Blur filter

The Selective Gaussian Blur filter

Original

The Selective Gaussian Blur filter

Blur applied


Contrary to the other blur plug-ins, the Selective Gaussian Blur plug-in doesn't act on all pixels: blur is applied only if the difference between its value and the value of the surrounding pixels is less than a defined Delta value. So, contrasts are preserved because difference is high on contrast limits. It is used to blur a background so that the foreground subject will stand out better. This add a sense of depth to the image with only a single operation.

3.4.2. Activate the filter

You can find this filter in the image menu under FiltersBlurSelective Gaussian Blur…

3.4.3. Options

Figuur 17.16. Selective Gaussian filter parameters settings

Selective Gaussian filter parameters settings

Presets, Preview, Split view

These options are common to GEGL-based filters. Please refer to Paragraaf 2, “Common Features”.

Aux. input

If there is another image on screen, you can select it as auxiliary input.

Blur radius

Here you can set the blur intensity, in pixels.

Max. delta

Here you can set the maximum difference (0-255) between the pixel value and the surrounding pixel values. Above this Delta, blur will not be applied to that pixel.