<%@ Page Language="C#" debug="true" %>
<%@ Import Namespace="System.Drawing" %>
<%@ Import Namespace="System.Drawing.Drawing2D" %>
<%@ Import Namespace="System.Drawing.Imaging" %> 
<%
	string filename = this.Request.QueryString["img"];
	string scale_mode = this.Request.QueryString["scale"];
	int width = Int32.Parse(this.Request.QueryString["width"]);
	int height = Int32.Parse(this.Request.QueryString["height"]);

	if(filename.StartsWith("http://", StringComparison.OrdinalIgnoreCase)) {
		filename = this.Server.MapPath(VirtualPathUtility.ToAppRelative(new Uri(filename).AbsolutePath));
	} else {
		filename = this.Server.MapPath("") + "/" + filename;
	}

	using(System.Drawing.Image img_source = System.Drawing.Image.FromFile(filename)) {
		const int orig_x = 0;
		const int orig_y = 0;
		int orig_w = img_source.Width;
		int orig_h = img_source.Height;
		float scale_x = (float)width / orig_w;
		float scale_y = (float)height / orig_h;
		float scale = 1;
		switch(scale_mode.ToLower()) {
			case "fit":
				scale = Math.Min(Math.Min(scale_x, scale_y), 1);
				break;
			case "crop":
				scale = Math.Max(scale_x, scale_y);
				break;
			case "fill":
				scale = Math.Max(scale_x, scale_y);
				break;
			case "fix":
				scale = scale_y;
				break;
		}
		const int dest_x = 0;
		const int dest_y = 0;
		int dest_w = (int)(orig_w * scale);
		int dest_h = (int)(orig_h * scale);
		using(Bitmap thumb = new Bitmap(dest_w, dest_h, PixelFormat.Format24bppRgb)) {
			thumb.SetResolution(img_source.HorizontalResolution, img_source.VerticalResolution);
			using(Graphics graphics = Graphics.FromImage(thumb)) {
				graphics.InterpolationMode = InterpolationMode.HighQualityBicubic;
				graphics.SmoothingMode = SmoothingMode.HighQuality;
				graphics.CompositingQuality = CompositingQuality.HighQuality;
				graphics.DrawImage(img_source,
								   new Rectangle(dest_x - 1, dest_y - 1, dest_w + 2, dest_h + 2),
								   new Rectangle(orig_x, orig_y, orig_w, orig_h),
								   GraphicsUnit.Pixel);
			}
			ImageCodecInfo codec = ImageCodecInfo.GetImageEncoders()[1];
			EncoderParameters eParams = new EncoderParameters(1);
			eParams.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, 100L);
			thumb.Save(this.Page.Response.OutputStream, codec, eParams);
		}
	}
%>