Automatically Detect and Insert Image [name based on alias] Into Joomla Template

gistfile1.aw

<?php
	$itemId = JRequest::getInt('Itemid', 0);
	if ($itemId) {
		$currentAlias 	= JSite::getMenu()->getActive()->alias;
		$altText 		= str_replace("-"," ",$currentAlias);
		$fileTypes 		= array('png','jpg','jpeg','gif');
		foreach ($fileTypes as $fileType) {
			$headerImage = JPATH_BASE . '/images/banners/' . $currentAlias . '.' . $fileType;
			if(JFile::exists($headerImage)) {
				list($width, $height, $type, $attr) = getimagesize($headerImage);
				echo '<img class="article-banner" src="'.JURI::base().'images/banners/' . $currentAlias . '.' . $fileType.'"'. $attr .'alt="' . $altText .'" />';
				break;
			}
		}
	}
?>