7.6. Sobel
| 7. Edge-Detect Filters |

### 7.6. Sobel

#### 7.6.1. Overview

Figure 16.146. Applying example of the Sobel filter

Original image

Filter “Sobel” applied

Sobel's filter detects horizontal and vertical edges separately on a scaled image. Color images are turned into RGB scaled images. As with the Laplace filter, the result is a transparent image with black lines and some rest of colors.

#### 7.6.2. Activating the filter

You can find this filter through Filters → Edge detect → Sobel.

#### 7.6.3. Options

Figure 16.147. Sobel filter options

Preview

  If checked, changes in the image are displayed in the Preview in real time before being applied to the image.

Sobel Horizontally

  Renders near horizontal edges.

Sobel Vertically

  Renders near vertical edges.

Keep sign of result

  This option allows you to set how the filter will work if you have selected one direction for use only: a flat relief with bumps and hollows will be created.

7.5. Neon |  | 8. Generic Filters