examples.sigmoidalContrast source code

1 /**
2  * Copyright: Mike Wey 2011
3  * License:   zlib (See accompanying LICENSE file)
4  * Authors:   Mike Wey
5  * 
6  * This is an translation of the sigmoidal contrast example
7  * that can be found on the ImageMagick website:
8  * http://www.imagemagick.org/source/core/sigmoidal-contrast.c
9  * 
10  * Mainly to demonstrate the parallel execution of the foreach
11  * over the ImageView, normaly you whould use Image.sigmoidalContrast.
12  */
13 
14 module examples.sigmoidalContrast;
15 
16 import std.math;
17 import std.stdio;
18 
19 import dmagick.ColorRGB;
20 import dmagick.Image;
21 
22 void main(string[] args)
23 {
24 	if ( args.length != 3 )
25 	{
26 		writefln("Usage: %s image sigmoidal-image", args[0]);
27 		return;
28 	}
29 
30 	Image image = new Image(args[1]);
31 
32 	//The Body of this loop is executed in parallel.
33 	foreach ( row; image.view )
34 	{
35 		foreach ( ColorRGB pixel; row )
36 		{
37 			pixel.red     = SigmoidalContrast(pixel.red);
38 			pixel.green   = SigmoidalContrast(pixel.green);
39 			pixel.blue    = SigmoidalContrast(pixel.blue);
40 			pixel.opacity = SigmoidalContrast(pixel.opacity);
41 		}
42 	}
43 
44 	image.write(args[2]);
45 }
46 
47 double SigmoidalContrast(double q)
48 {
49 	return ((1.0/(1+exp(10.0*(0.5-q)))-0.0066928509)*1.0092503);
50 }