High Quallity Image Resizing in Medium Trust?

**Leigh** · 18th January 2007, 10:16 PM

I need to be able to dynamically resize images prior to rendering them. I've found a couple of solutions, but they all fail to work in medium true due to unmanaged/unsafe code (namely the OctreeQuantizer). http://www.glennjones.net/Post/799/H...geswithnet.htm is one such example.

Is there a .Net 2.0 component (free or chargeable) that I can just plug into my ASP.Net site to do this?

Alternatively, has anyone managed to get (high quality) image resizing working with their medium trust, RedFox hosted site? Does anyone have any C# 2.0 code to do this?

**Staff: Warren Ashcroft** · 18th January 2007, 10:53 PM

Cant you use GDI (System.Drawing namespace) under Medium Trust? Heres what I used in a recent project:

Code:

    Public Shared Sub ResizeImage(ByRef image As Bitmap, ByVal width As Integer, ByVal height As Integer, Optional ByVal antiAlias As Boolean = False)
        Dim NewImage As New Bitmap(width, height)
        Dim Graphics As Graphics = Drawing.Graphics.FromImage(NewImage)
        If antiAlias Then Graphics.InterpolationMode = Drawing2D.InterpolationMode.HighQualityBilinear
        Graphics.DrawImage(image, 0, 0, width, height)
        image = NewImage
    End Sub

...set the antiAlias boolean for high quality resizing.

**Staff: Warren Ashcroft** · 18th January 2007, 10:56 PM

Sorry, should have read the link you posted - even so using HighQualityBilinear I couldnt complain with the resize quality.

**RFH Reseller: JohnnyW** · 19th January 2007, 04:15 PM

What type of images are you going to be resizing. If it's images with text on them as an eps or gif which GDI+ can also do maybe your best option to keep the text sharp.

I output my images as eps's on comedyquotes.net as they are mainly text based.

If it has to be JPEG you can adjust the quality/compression of the JPEG from within your code.

I use JPEG output on igapyear.com as they are mainly pictures without text.