public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) { PNM pnm = value as PNM; if (pnm == null) { return(null); } var bitmap = new WriteableBitmap(pnm.Width, pnm.Height, 96, 96, PixelFormats.Cmyk32, null); bitmap.WritePixels(new Int32Rect(0, 0, pnm.Width, pnm.Height), pnm.GetCMYK(), pnm.Width * 4, 0); return(bitmap); }