Image Scale HTTP Handler

<%@ WebHandler Language="C#" Class="ScaledImage" %>

using System;
using System.Web;

using System.IO;
using System.Drawing;
using System.Drawing.Imaging;

// ScaledImage.ashx?image=101&width=200&height=300
public class ScaledImage : IHttpHandler {
    public static class ImageHelper {
        private static void AdjustGraphics(Graphics gr) {
            gr.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
            gr.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
            gr.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
        }

        private static bool NeedCrop(int targetWidth, int targetHeight, Image image) {
            double widthFactor = (float)image.Width/targetWidth;
            double heightFacor = (float)image.Height/targetHeight;

            return widthFactor - (int) widthFactor >= 0.2 | heightFacor - (int) heightFacor >= 0.2;
        }

        private static Image CropImage(Image image, int width, int height) {
            int newWidth = image.Width/width*width;
            int newHeight = image.Height/height*height;
            Rectangle cropRect = new Rectangle((image.Width - newWidth)/2, (image.Height - newHeight)/2, newWidth, newHeight);
            Bitmap result = new Bitmap(newWidth, newHeight);
            using(Graphics gr = Graphics.FromImage(result)) {
                AdjustGraphics(gr);
                gr.DrawImage(image, 0, 0, cropRect, GraphicsUnit.Pixel);
            }
            return result;
        }

        private static Image ResizeImage(Image image, int width, int height) {
            Bitmap result = new Bitmap(width, height);
            using (Graphics gr = Graphics.FromImage(result)) {
                AdjustGraphics(gr);
                gr.DrawImage(image, 0, 0, result.Width, result.Height);
            }
            return result;
        }

        public static MemoryStream ResizeImage(string path, int width, int height) {
            using (Image image = Image.FromFile(path)) {
                Image result = null;

                if (image.Width <= width && image.Height <= height) {
                    result = image;
                }
                else {
                    if (NeedCrop(width, height, image)) {
                        using (Image croppedImage = CropImage(image, width, height)) {
                            result = ResizeImage(croppedImage, width, height);
                        }
                    }
                    else {
                        result = ResizeImage(image, width, height);
                    }
                }

                MemoryStream stream = new MemoryStream();
                result.Save(stream, ImageFormat.Jpeg);
                if (result != image) result.Dispose(); // small kludge not to use to much using statements
                return stream;
            }
        }
    }

    public const string IMAGE_PARAM = "image";
    public const string WIDTH_PARAM = "width";
    public const string HEIGHT_PARAM = "height";

    public void ProcessRequest (HttpContext context) {
        string path = context.Server.MapPath(string.Format("~/images/image{0}.jpg", ImageId));
        path = File.Exists(path) ? path : context.Server.MapPath("~/images/noimage.jpg");

        context.Response.ContentType = "image/jpg";
        using (MemoryStream stream = ImageHelper.ResizeImage(path, TargetWidth, TargetHeight)) {
            stream.WriteTo(context.Response.OutputStream);
        }
    }

    private int GetIntParam(string paramName) {
        string value = HttpContext.Current.Request[paramName];
        int result;
        bool success = Int32.TryParse(value, out result);
        return success ? result : -1;
    }

    private int ImageId {
        get { return GetIntParam(IMAGE_PARAM); }
    }

    private int TargetWidth
    {
        get { return GetIntParam(WIDTH_PARAM); }
    }

    private int TargetHeight
    {
        get { return GetIntParam(HEIGHT_PARAM); }
    }

    public bool IsReusable {
        get {
            return false;
        }
    }
}