4.7. Symmetric Nearest Neighbor

4.7. Symmetric Nearest Neighbor
	4. Enhance Filters

4.7.1. Overview

This filter blurs the image preserving edges. It is very effective in noise reduction maintaining sharp edges.

It works comparing each pixel to its neighboring pixels and to 1 or 2 pairs of symmetric pixels around the center.

4 symmetric pairs

4.7.2. Activating the filter

You can find this filter through Filters → Enhance → Symmetric Nearest Neighbor….

4.7.3. Options

Figure 17.37. “Symmetric Nearest neighbor” filter options

Presets, Preview, Split view

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

Radius

Radius, in pixels, of square pixel region. Width and height of this region are radius*2+1:

Pairs

You can select 1 or 2 pairs : higher number preserves more acute features.

Clipping

The result of this filter can be larger than the original image. With the default Adjust option, the layer will be automatically resized as necessary when the filter is applied. With the Clip option the result will be clipped to the layer boundary.

4.7.4. Example

Left: original..............Right: filter applied