Follow Techotopia on Twitter

On-line Guides
All Guides
eBook Store
iOS / Android
Linux for Beginners
Office Productivity
Linux Installation
Linux Security
Linux Utilities
Linux Virtualization
Linux Kernel
System/Network Admin
Programming
Scripting Languages
Development Tools
Web Development
GUI Toolkits/Desktop
Databases
Mail Systems
openSolaris
Eclipse Documentation
Techotopia.com
Virtuatopia.com

How To Guides
Virtualization
General System Admin
Linux Security
Linux Filesystems
Web Servers
Graphics & Desktop
PC Hardware
Windows
Problem Solutions

  




 

 

5.5.  Sparkle

5.5.1.  Overview

Figure 16.104.  Applying example for the Sparkle filter

Applying example for the Sparkle filter

Original image

Applying example for the Sparkle filter

Filter “Sparkle” applied


This filter adds sparkles to your image. It uses the lightest points according to a threshold you have determined. It is difficult to foresee where sparkles will appear. But you can put white points on your image where you want sparkles to be.

5.5.2.  Activate the filter

This filter is found in the image window menu under FiltersLight and ShadowSparkle.

5.5.3.  Parameter Settings

Figure 16.105.  Sparkle” filter options

Sparkle filter options

Sliders and input boxes allow you to set values.

Preview

Parameter setting results are interactively displayed in preview. Scroll bars allow you to move around the image.

Luminosity Threshold

The higher the threshold, the more areas are concerned by sparkling (0.0-0.1).

Flare Intensity

When this value increases, the central spot and rays widen (0.0-1.0).

Spike Length

This is ray length (1-100). When you reduce it, small spikes decrease first.

Spike Points

Number of starting points for spikes (0-16). It's the number of big spikes. There is the same number of small spikes. When number is odd, small spikes are opposite the big ones. When number is even, big spikes are opposite another big spike.

Spike Angle

This is angle of first big spike with horizontal (-1 +360). -1 determines this value at random. If a spot has several pixels within required threshold, each of them will generate a sparkle. If angle is positive, they will all be superimposed. With -1, each sparkle will have a random rotation resulting in numerous thin spikes.

Spike Density

This option determines the number of sparkles on your image. It indicates the percentage (0.0-1.0) of all possible sparkles that will be preserved.

Opacity

When you decrease Opacity (0.0-1.0), sparkles become more transparent and the layer beneath becomes visible. If there is no other layer, sparkle saturation decreases.

Random Hue

This option should change sparkle hue at random... (0.0-1.0)

Random Saturation

This option should change sparkle saturation at random... (0.0-1.0)

Preserve Luminosity

Gives to all central pixels the luminosity of the brightest pixel, resulting in increasing the whole sparkle luminosity.

Inverse

Instead of selecting brightest pixels in image, Sparkle will select the darkest ones, resulting in dark sparkles.

Add Border

Instead of creating sparkles on brightest pixels, this option creates an image border made up of numerous sparkles.

Natural, Foreground, Background Colors

You can change there the color of central pixels. This color will be added in Screen mode (Multiply if Inverse is checked). You can select between Natural color (the color of the pixel in the image), Foreground color and Background color.


 
 
  Published under the terms of the GNU General Public License Design by Interspire