PDF/A files sometimes grow really large


I am converting different documents to pdf/a and usually I need to generate pdf/a-1a. Some times the documents grow a lot, and I am hoping you can help me understand what is happening and hopefully find a solution to this.

PowerPoint.zip (1.7 MB)

In the attached zip-file is an example document, PowerPoint.pptx which is a 49 kB file. When generating a pdf/a-1a or pdf/a-1b the output file grows almost 20 times to 831 kB. But when generating pdf/a-2a, pdf/a-2b, pdf/a-3a or pdf/a-3b the target file actually shrinks to 45 kB. And when looking at the result, the pdf/a 2 and 3 files are visually much better looking.

With this example document I use Aspose.Slides.Presentation to save the PowerPoint as pdf and I use Aspose.Pdf.Document to convert the pdf to pdf/a. I have validated all the pdf/a output files using Adobe Preflight.

The attached zip-file contains the example powerpoint document and the six different generated pdf/a versions of it.

Thank you for your help!

Best regards,


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We have worked with the data shared by you and have been able to notice the difference in our environment. A ticket with ID PDFNET-45462 has been logged in our issue management system for further investigation and resolution. The ticket ID has been linked with this thread so that you will receive notification as soon as the ticket is resolved.

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