/**
* Implementation of hook_form_alter().
*/
 
function epsalmo_form_alter(&$form, &$form_state, $form_id) {
  switch ($form_id)   {    
    case 'story_node_form':
        $form['#after_build'][] = 'epsalmo_after_build';
    break;
  }
}
 
/**
* Implementation of hook_after_build().
*/
 
function epsalmo_after_build($form, &$form_state) {
  foreach (element_children($form['group_images']['field_image']) as $key) {
    $form['group_images']['field_image'][$key]['data']['title']['#title'] = 'Copyright ';
    $form['group_images']['field_image'][$key]['data']['description']['#title'] = 'Legende ';
  }
 
return $form;
}