[VB.NET] อยากกำหนดขนาดของรูปที่เลือกมาให้เป็นขนาด 100*100 ต้องทำยังไงหรอครับ

Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
        'Dim resizeimg As Image
        Try
            Dim digiImage As FileDialog = New OpenFileDialog()
            digiImage.Filter = "Image File (*.jpg;*.bmp;*.gif)|*.jpg;*.bmp;*.gif"

            If digiImage.ShowDialog() = DialogResult.OK Then

                imgName = digiImage.FileName
                Dim newimg As New Bitmap(imgName)

                PictureBox1.SizeMode = PictureBoxSizeMode.StretchImage
                PictureBox1.Image = DirectCast(newimg, Image)



            End If

            digiImage = Nothing
        Catch ae As System.ArgumentException
            imgName = " "
            MessageBox.Show(ae.Message.ToString())
        Catch ex As Exception
            MessageBox.Show(ex.Message.ToString())
        End Try
    End Sub