Private imageFile As Bitmap
 
    Private Sub tsbOpenImage_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles tsbOpenImage.Click
        If OpenFileDialog1.ShowDialog = Windows.Forms.DialogResult.OK Then
            Dim strFileName As String
            strFileName = OpenFileDialog1.FileName
            imageFile = New Bitmap(strFileName)
 
            PictureBox1.Image = imageFile
        End If
    End Sub
 
    Private Sub tsbSave_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles tsbBack.Click
        If SaveFileDialog1.ShowDialog = Windows.Forms.DialogResult.OK Then
            imageFile.Save(SaveFileDialog1.FileName)
        End If
    End Sub

imageFile.Save(SaveFileDialog1.FileName, Drawing.Imaging.ImageFormat.Png)