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PDF to TIF conversion using C#


When attempting to convert one PDF, I get Aspose.Pdf.InvalidValueFormatException thrown with the message “Date has invalid format “””". The PDF in question has no dates in the Created or Modified metadata fields, I assume the library is expecting these to be populated.

When attempting to convert another PDF (58 pages, 28mb), I catch a System.OutOfMemory exception with the message “A generic error occurred in GDI+”.

The conversion output filetype is TIF with LZW compression.

On the subject of memory, is it possible to reduce memory usage during the conversion by cachine to disk in some way? I need conversion to work on computers with potentially limited amounts of memory.

I’m using the library inside an application running on a client machine, not as a webservice.



Thanks for taking interest in GroupDocs.Conversion and posting your concerns. In order to investigate the issue at our end, we are required following details from you:

  • Are you using our document conversion API for Java or .NET platform?
  • Which version of the API you are evaluating or integrated in your application?
  • Please share the problematic files with us.

We’ll appreciate your cooperation in this regards. As far as following issue is concerned:

You can enable cache in order to reduce memory usage and time.


I’m using the conversion API for the .NET platform, version 17.9, I am evaluating the library.

Unfortunately I cannot share the files directly with you since they are confidential. The first PDF actually has no create/modified date fields. As far as I’m aware there are no other actual dates in the file. I’ve dumped the metadata table below:
InfoKey: Author
InfoValue: KODAK Capture software
InfoKey: Producer
InfoValue: Eastman Kodak Company
InfoKey: Creator
InfoValue: KODAK Capture
InfoKey: Build
InfoValue: FyTek’s PDF Meld Commercial Version 7.2.1 as of August 6, 2006 20:23:50
NumberOfPages: 175

Regarding the GDI+ error, I believe it is actually a TIF inside the PDF that is causing the crash, I may be able to get you a copy of this, I’m working on extracting it.

I did try enabling the cache, I set the cachedir to a folder within our AppData directory and set UseCache to true but the application just hanged on the call to ConversionHandler.Convert.



I have a PDF to replicate the first issue with the invalid date format, I have attached it. Still working on the second issue.


datevalue_crash.pdf (141.0 KB)


Thanks for sharing the problematic file. We easily reproduced this issue (error while converting metadata free PDF to TIF) at our end. Hence, we’ve logged it in our internal issue tracking system with ID:CONVERSIONNET-2240. As we get any update from the concerned team, we shall apprise you. However, as far as second issue is concerned, we’d like you to go through our Privacy Policy. You can share the other problematic file with us.

Let us elaborate you how cache works. If you are required to convert a large document time by time. You can enable cache and document conversion will take time and resources for the first time only. Later, with cache enabled, it won’t take much time to convert same document. API will utilize cached data. Further, we’ll investigate the issue (application hang) once you share the problematic file with us.


We’d like to notify you that your reported issue CONVERSIONNET-2240 is resolved. Please download the latest release here and share your feedback.