Remove first image to Instant Article

Hi,

because of our template we are forced to place two identical images: a as the first image and another as Featured Image. We wanted to eliminate about Instant Article the first image, otherwise it shows as duplicated.

How can we do? Already we have hidden the first image on the site with this code below (posted in function.php).

function remove_first_image ($content) {
if (!is_page() && !is_feed() && !is_feed() && !is_home()) {
$content = preg_replace(“/<img[^>]+\>/i”, “”, $content, 1);
} return $content;
}
add_filter(‘the_content’, ‘remove_first_image’);

How can we do the same for Page Frog for Instant Article?

See this image? -> https://dl.dropboxusercontent.com/u/22334399/Schermata%202016-06-14%20alle%2012.05.49.png

https://www.ads-software.com/plugins/pagefrog/