Monthly Archives: March 2010

Mar 08

Change image hue with PHP

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I am considering changing the color of my dojo grids so it is easier to distinguish them because there will be so many on one page (this is an internal application). I have not worked through the CSS changes which could be a small challenge but more on that to later. For now this is the php code that I used to change the hue on the images from the soria theme. I am using ImageMagick, specificly the modulateImage function. Yes, I did search and could not find any existing app that could batch change the hue, so PHP came to my rescue! 
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<?php
$originalPath ='/dojo/chadsmiley/Themes/soria/';
$path ='/dojo/chadsmiley/Themes/Hue30/';
 
$dir_handle = @opendir($originalPath);
 
//running the while loop
while ($file = readdir($dir_handle)){
	   if($file!="." && $file!=".."){
 
			$img = new Imagick();
			$img->readImage($originalPath.$file);
			 /**
			   *@var brightness 100 = no change
			   *@var saturation 100 = no change 
			   *@var hue (percentage of absolute rotation from the current position)
			   */
			$img->modulateImage(100, 100, 30);
			$img->writeImage($path.$file);
			$img->clear();
			$img->destroy();
	   }
}
 
//closing the directory
closedir($dir_handle);
 
?>