Resizing images on the server side (ASP.NET)

Let’s say, you have images (blob) stored in your database. Now you want to resize and generate a thumbnail out of it before you can send it back on the Response stream to be displayed on the page. Here is a way to resize the original image.

• Read the image (blob) into a byte array

byte[] image = null;
while (dr.Read())
{
  image = (byte[])dr.GetValue(0);
}
dr.Close()

• Convert the byte array into Bitmap

Bitmap b = (Bitmap)Bitmap.FromStream( new MemoryStream(image));

• Resize the Bitmap

Bitmap output = new Bitmap(b, new Size(320, 240);

Once resized you can save it as an external file or you can attach it with the Response.OutputStream.