Imports System.IO
Imports System.Drawing.Imaging
Public Class Form1
    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        ' set Filename to blank
        OpenFileDialog1.FileName = ""
        ' fileter onyl bmp files
        OpenFileDialog1.Filter = "All Files|*.*"
        If OpenFileDialog1.ShowDialog() = DialogResult.OK Then
            Dim raw As Byte() = System.IO.File.ReadAllBytes(OpenFileDialog1.FileName)
            Path.GetDirectoryName(OpenFileDialog1.FileName)
            Using img As Image = Image.FromStream(New MemoryStream(raw))
                img.Save(OpenFileDialog1.InitialDirectory + OpenFileDialog1.FileName.Replace(".png", ".jpg"), ImageFormat.Jpeg)
            End Using
        End If

    End Sub
End Class