Convert PDF to PDF/A-3

PDF/A is an ISO-standardized subset of PDF designed for long-term archiving, and PDF/A-3 is the only PDF/A version that allows any file type to be attached to the document. JPedal provides a PdfA3Converter class to convert PDF files into valid PDF/A-3 files, either in Java or from the command line.

Converting a PDF to PDF/A-3 in Java

Create a PdfA3Converter with the conformance level to validate against, then call convert. Currently, only PdfA3Converter.Level.B is supported.

// Create an instance
final PdfA3Converter converter = new PdfA3Converter(PdfA3Converter.Level.B);

// Convert an unencrypted file
final PdfA3Converter.ConversionResult result = converter.convert(new File("inputFile.pdf"), new File("outputFile.pdf"));

// Convert a password-protected file
final PdfA3Converter.ConversionResult result = converter.convert(new File("inputFile.pdf"), "password".getBytes(), new File("outputFile.pdf"));

There are also method overloads which allow you to use an InputStream or a byte[] as input.

Checking the result of a conversion

convert returns a PdfA3Converter.ConversionResult, which lists any issues found with the file and any lossy changes made to fix them. If issues is empty, the output file is PDF/A-3b compliant; if it is not empty, no output file is written.

if (result.issues().isEmpty()) {
    // If no issues reported then file converted successfully
    // A list of changes to the file are also reported
    System.out.println("Success!");
    
    for (final String change : result.changes()) {
        // Iterate over lossy changes made to the file to make it compliant
    }
} else {
    // File was not able to convert
    System.out.println("Failure");
    
    for (final String issue : result.issues()) {
        // Iterate over issues found with the file
    }
}

Linearizing the output

The converted file can also be linearized for fast web view, allowing the first page to be displayed before the whole file has been downloaded. Linearization is disabled by default. Enable it with setLinearizeDocument before calling convert, and check the current setting with isLinearizeDocument.

final PdfA3Converter converter = new PdfA3Converter(PdfA3Converter.Level.B);
converter.setLinearizeDocument(true);

final PdfA3Converter.ConversionResult result = converter.convert(new File("inputFile.pdf"), new File("outputFile.pdf"));

Note that this setting only applies when converting to a File. It is not available from the command line.

Converting a PDF to PDF/A-3 from the command line

PdfA3Converter can also be run from the command line to convert one or more files, or all the PDF files in a directory, into an output directory.

java -cp jpedal.jar org.jpedal.tools.pdfa.PdfA3Converter --level B --output outputFolder inputFile1.pdf inputFile2.pdf

Files can also be passed with --input/-i, each optionally followed by --password/-p and a password for that file. Only files passed this way can have a password argument.

java -cp jpedal.jar org.jpedal.tools.pdfa.PdfA3Converter --level B --output outputFolder --input inputFile1.pdf --input inputFile2.pdf --password inputFile2Password

An input can also be a directory, in which case every PDF file it contains is converted. You cannot provide passwords for entire directories.

java -cp jpedal.jar org.jpedal.tools.pdfa.PdfA3Converter --level B --output outputFolder inputFolder

Confirming compliance

Note it is recommended to confirm the compliance of a converted PDF/A-3 file with a validation tool such as veraPDF, which is the PDF Association’s free, open-source reference implementation.