This is a prototype WordPress plugin for using imagemagick filters on your wordpress images. The original tutorial that accompanied the Instagraph class is on netttuts here.

The Instagraph class was written by Dejan Marjanovic of http://webarto.com/ (Thanks Dejan!)

There is currently no UI but it is planned to be able to select a default filter.

To use the filters in your templates you have to call image sizes in the following way:

<?php

    the_post_thumbnail( 'medium:kelvin' );

?>

In the above the image size requested is 'medium' and the filter to use is 'kelvin'.

The supplied filters are 'lomo', 'nashville', 'kelvin', 'toaster', 'gotham', 'tilt_shift'.

You can register new filters in the following way:

<?php

register_instagraph_filter( 'custom_filter', 'custom_filter_callback' );

function custom_filter_callback( $this ) {
    $this->tempfile();

    $command = "convert $this->_tmp -channel B -level 33% -channel G -level 20% $this->_tmp";

    $this->execute($command);
    $this->vignette($this->_tmp);

    $this->output();
}

?>

This was a quickly made hack so it will need work, and hopefully some contributions! Go play.

If you have any questions use the issue tracker here or get me on twitter @sanchothefat.