Apose.Pdf produces hieroglphys when konverting PDF tio Tif files

Ladies and gentlemen.
when converting pdf fils to tif using aspose.pdf
public override void ConvertAndCreateSingleFile(string source, string outputImageFile, int xDpi = 300,
int yDpi = 300)
if (!AsposeLibrary.InitPdfLicense())
throw new Exception(“Aspose licence cannot be obtained !!”);
var pdfdocument = new Document(source) {DisplayDocTitle = true};

        var resolution = new Resolution(xDpi);

        var tiffSettings = new TiffSettings
            Compression = CompressionType.CCITT4,
            Depth = ColorDepth.Format8bpp,
            Shape = ShapeType.Portrait,
            SkipBlankPages = false,
            Brightness = 0.9f

        var tiffDevice = new TiffDevice(resolution, tiffSettings);

        tiffDevice.Process(pdfdocument, outputImageFile);

        if (File.Exists(outputImageFile))
            this.LastConversionWasSuccessful = true;

Normally ther is no problem.
But once in a while the method produces hieroglyphs. (unreadyble garbage)
I tried with Aspose.pdf version 17.9

9873d55d-271d-419a-a607-bbdf82a8d9f6.0.pdf (145.4 KB)

I anylyzed he file in question with help of the aspose.validate method and there are only few error.
Oher fiels, with more errors are rendered successfully.

D:\Test\QuickTest\9873d55d-271d-419a-a607-bbdf82a8d9f6.0.pdf 1.6 false true 1.0 Copyright (c) 2001-2012 Aspose Pty Ltd. All Rights Reserved. 12.09.2017 14:07:49 Width information for glyphs is inconsistent in embedded font 'EABGEF+Arial-BoldMT' Width information for glyphs is inconsistent in embedded font 'EABGEE+TimesNewRomanPS-ItalicMT' The instanceID field shall not be specified The catalog entry OCProperties is prohibited

Kind regards

Martin Hock

We managed to replicate the problem of unreadable text in our environment. It has been logged under the ticket ID PDFNET-43339 in our bug tracking system. We have linked your post to this ticket and will keep you informed regarding any available updates.