Fix the same expression in crop()
diff --git a/system/libraries/Image_lib.php b/system/libraries/Image_lib.php
index 39f9887..dc7d362 100644
--- a/system/libraries/Image_lib.php
+++ b/system/libraries/Image_lib.php
@@ -408,7 +408,7 @@
 	 */
 	public function crop()
 	{
-		$protocol = (strtolower(substr($this->image_library, 0, -3)) === 'gd2') ? 'image_process_gd' : 'image_process_'.$this->image_library;
+		$protocol = ($this->image_library === 'gd2') ? 'image_process_gd' : 'image_process_'.$this->image_library;
 		return $this->$protocol('crop');
 	}