Change Base64 png image to jpeg

The base64 string: data:image/png;base64,iVBORw0KGgoAA etc......

Public Function SaveBase64ToImage(ByVal base64 As String)
        Try
            Using ms As New MemoryStream(Convert.FromBase64String(base64))
                Using bm As New Bitmap(ms)
                    bm.Save(ms, System.Drawing.Imaging.ImageFormat.jpg)
                    Return bm
                End Using
            End Using
        Catch ex As Exception
            Return Nothing
        End Try
    End Function

Public Shared Function ImageToBytes(img As Image) As Byte()
        If img Is Nothing Then Return Nothing
        Dim ms As New MemoryStream()
        img.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg)  
        Return ms.ToArray()
    End Function