Laravel从html-str_limit中删除iframe和img

I'm using str_limit($data['last_post']['content'],800) in blade for display first 800 characters from post. The problem is when user post video or image at the beginning of post. My question is: how to filter and remove iframe, img and display post first characters without this tags?

My recommendation would be to simply use $result = stripslashes($postDescription) then use the below function to remove the iframe or image tags

function replacePostDesriptionUrls($postDesc = null) {
    $regex = '/<iframe.*?>(.*?)<\/iframe>/';

    return preg_replace_callback($regex, 
        function($m){
            return escapeLink($m[0]);
        }, $postDesc);
}

Do the same for any tags you want to remove from your post description.