Model view and labels are not displayed correctly

Hello, I created a model view and labels are not displayed correctly. Here are the contents of my model views-view-field--sitemap--views-data-export--field-image.tpl.php :

<?php

$fields["field_image"]->content = '<image:loc>' . $field->original_value . '</image:loc>';

echo $fields["field_image"]->content;

the result is :
<image:loc>http://www.domaine.com/xxx.jpg</image:loc>

instead of :
<image:loc>http://www.domaine.com/xxx.jpg</image:loc>