Is there any ways to check image width during uploading process?

I got image resize script, so I just need to know the if statement. (following statement in bold)

something like..
If uploading image width > 640 then
     resize image and save
else
    save
end if

Thank you

http://www.freevbcode.com/ShowCode.asp?ID=112

I think I figure it out.

Dim originalBMP As New System.Drawing.Bitmap(FileField.FileContent)
If originalBMP.Width > 640 Then

resize

end if