public string getVideoImage(string post_id, string sub_post_id)
{
string decoded_post_id = helper.DecodeFrom64(post_id);
string decoded_sub_post_id = helper.DecodeFrom64(sub_post_id);
Post p = pm.GetVideoImages(decoded_post_id, decoded_sub_post_id);
User u = um.GetUser_Detail(p.owner._id);
p.owner.user_name = u.first_name + " " + u.last_name;
p.owner.user_picture = u.profile_img;
return(JsonConvert.SerializeObject(p));
}