upload image then resize image handler

Hi Guys i have a handler page - upload.ashx

That uploads a file fine. I want to add Resize functionality to that, i searched for a resize function on the forums but cant figure out how i would call it during/after the upload? What do i put in for the variable "stream buffer"?

This is what i've got so far, appreciate any help you can give me -
 
 <%@ WebHandler Language="C#" Class="Uploader" %>

using System.IO;
using System.Web;
using System.Web.Configuration;


public class Uploader : IHttpHandler
{   
  public void ProcessRequest( HttpContext _context )
        {
          // not very elegant - change to full path of your upload folder (there are no upload folders on my site)

            s ...