hello, I found a macro that does exactly what I need, but the detail is that I want to change it to grayscale, and I don't know how to do it, I leave you the macro:

  Dim s As Shape
  For Each s In ActivePage.Shapes
    If s.Type = cdrBitmapShape Then
      If s.Bitmap.Mode = cdrRGBColorImage Then
        s.Bitmap.ConvertToBW cdrRenderLineArt, , 97
      End If
    End If
  Next s
End Sub

Thank you