Public Class Form1
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles MyBase.Load
        PictureBox1.SizeMode = PictureBoxSizeMode.AutoSize
        PictureBox2.SizeMode = PictureBoxSizeMode.AutoSize
        PictureBox3.SizeMode = PictureBoxSizeMode.AutoSize
        PictureBox1.Image = New Bitmap("C:\W-Intern\kug1.bmp")
        PictureBox2.Image = New Bitmap("C:\W-Intern\kug2.bmp")
    End Sub
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button1.Click
        PictureBox3.Image = BitmapDiff(CType(PictureBox1.Image, Bitmap), CType( _
        PictureBox2.Image, Bitmap))
    End Sub
 
    Private Function BitmapDiff(ByVal b1 As Bitmap, ByVal b2 As Bitmap) As _
      Bitmap
        Dim bm As New Bitmap(b1.Width, b1.Height)
        For y As Integer = 0 To b1.Height - 1
            For x As Integer = 0 To b1.Width - 1
                If b1.GetPixel(x, y) <> b2.GetPixel(x, y) Then
                    bm.SetPixel(x, y, b1.GetPixel(x, y))
                End If
            Next
        Next
        Return bm
    End Function
End Class