NullifyNetwork

This is a nice neat way of resizing an image, I've simplified it and de-refactored (?) it for simplicity.

Firstly, you ask for your image from the database:

SqlCommand cmd = new SqlCommand("SELECT image FROM images WHERE id=@id", connection);
cmd.Parameters.Add("@id", Request.QueryString["id"]);
SqlDataReader dr = cmd.ExecuteReader();

Allocate an array of bytes to store it in temporarily:

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

Now you have an array of bytes that contains your image, you can freely load it into a bitmap from the array:

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

And you can resize that bitmap easily using the overloaded bitmap constructor:

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

One resized bitmap that you can now save or send anywhere - including Response.OutputStream!