WordPress Version: 4.6
/**
* Displays the post thumbnail caption.
*
* @since 4.6.0
*
* @param int|WP_Post $post Optional. Post ID or WP_Post object. Default is global `$post`.
*/
function the_post_thumbnail_caption($post = null)
{
/**
* Filters the displayed post thumbnail caption.
*
* @since 4.6.0
*
* @param string $caption Caption for the given attachment.
*/
echo apply_filters('the_post_thumbnail_caption', get_the_post_thumbnail_caption($post));
}