Why are some documents unable to be converted to PDF/A by ImageGear .NET?

We are saving files to the PDF/A standard and are running into a few cases where the file cannot be saved as PDF/A by ImageGear .NET. Why is this, and how do we do it properly?

First, determine whether a PDF document can be converted to PDF/A by creating an ImGearPDFPreflight object from your document, and generating an ImGearPDFPreflightReport object from it:

using (ImGearPDFPreflight preflight = new ImGearPDFPreflight((ImGearPDFDocument)igDocument))
{
    report = preflight.VerifyCompliance(ImGearPDFPreflightProfile.PDFA_1A_2005, 0, -1);
}

The first argument of the VerifyCompliance() method is the standard of PDF/A you want to use. ImageGear .NET is currently able to convert documents to adhere to the PDF/A-1A and PDF/A-1B standards:

PDF/A-1 Standard

ImageGear and PDF/A

There are parts of the PDF/A-2 and PDF/A-3 standards which may allow for more documents to be converted, but ImageGear .NET currently does not support those. This could possibly be why your document cannot be converted in ImageGear .NET.

Once the report is generated, you can access its Status, which will tell you if the document is fixable. You can also access its Code which will let you know if it’s a fixed page or if it has issues; it will return Success if fixed, or some error code otherwise. You can check these conditions to determine whether it’s worth attempting to convert the document:

// If the document is not already PDFA-1a compliant but can be converted
if ((report.Code == ImGearPDFPreflightReportCodes.SUCCESS) ||
(report.Status == ImGearPDFPreflightStatusCode.Fixable))
{
    ImGearPDFPreflightConvertOptions pdfaOptions = new ImGearPDFPreflightConvertOptions(ImGearPDFPreflightProfile.PDFA_1A_2005, 0, -1);
    ImGearPDFPreflight preflight = new ImGearPDFPreflight((ImGearPDFDocument)igDocument);
    preflight.Convert(pdfaOptions);
    saveFile(outputPath, igDocument);
}

// Create error message if document was not converted.
else if (report.Status != ImGearPDFPreflightStatusCode.Fixed)
{
    printAllRecordDescriptions(report);
    throw new ApplicationException("Given PDF document cannot be converted to PDFA-1a standard.");
}

If you want more information on why a document may not be convertible, you can access the preflight report for its records and codes. A preflight’s "Records" member is a recursive list of preflight reports. A preflight report will have a list of reports under Records, and each of those reports may have more reports, etc. You can recursively loop through them as seen below to output every reason a document is not convertible:

    private static void printAllRecordDescriptions(StreamWriter file, ImGearPDFPreflightReport report)
    {
        foreach (ImGearPDFPreflightReport rep in report.Records)
        {
            file.WriteLine(rep.Description);
            file.WriteLine(rep.Code.ToString() + "\r\n");
            printAllRecordDescriptions(file, rep);
        }
    }

Ultimately, the failure of a document to convert to PDF/A is non-deterministic. While some compliance failures can be corrected, in combination they may not be correctable. Therefore, the unfortunate answer is that to determine if it can be converted, conversion must be attempted.