--- /dev/null
+/**
+ * Implements hook_image_styles_alter().
+ */
+function {{ machine_name }}_image_styles_alter(&$styles) {
+ // Check that we only affect a default style.
+ if ($styles['thumbnail']['storage'] == IMAGE_STORAGE_DEFAULT) {
+ // Add an additional effect to the thumbnail style.
+ $styles['thumbnail']['effects'][] = array(
+ 'name' => 'image_desaturate',
+ 'data' => array(),
+ 'weight' => 1,
+ 'effect callback' => 'image_desaturate_effect',
+ );
+ }
+}