News Feed
Sections




News Archive
Looking for more information on how to do PHP the right way? Check out PHP: The Right Way

Philip Norton's Blog:
Desaturate Images With PHP
September 07, 2011 @ 12:51:26

In a new post to his blog Philip Norton shows how to desturate images with PHP using the already built-in GD libraries and the imagecopymergegray function.

To desaturate an image means to remove all non-greyscale colours from it, essentially creating a black and white version. To do this you can use the function imagecopymergegray(), which is part of the GD image library. This function is a little difficult to figure out, but what is does is sample one image into another and optionally changing the amount of colours that are kept during the sampling process. The function can be made to sample just a section of the image, or the whole thing.

He also offers an alternative method that uses imagefilter instead, passing it the IMG_FILTER_GRAYSCALE flag. Included is a full block of code for a method he recently included in a WordPress site to dynamically create thumbnails.

0 comments voice your opinion now!
desaturate image grayscale gd tutorial imagecopymergegray imagefilter


blog comments powered by Disqus

Similar Posts

PHPBuilder.com: Email Forms in PHP

Mayflower Blog: Creating coding standards for PHP_CodeSniffer

SitePoint.com: OAuth for PHP Twitter Apps, Part I

DevShed: Using Method Call Overloading in PHP 4

DevShed: Implementing the commit() and rollback() Methods with mysqli and PHP 5


Community Events





Don't see your event here?
Let us know!


symfony wordpress install library application list community podcast code threedevsandamaybe developer interview bugfix configure release laravel api series introduction language

All content copyright, 2014 PHPDeveloper.org :: info@phpdeveloper.org - Powered by the Solar PHP Framework