The FPDI PDF-Parser is an extension of the PDF parser that is shipped with FPDI by default. Just extract the content of this package to a folder of your choice and add the /src folder to your PSR-4 autoload implementation: $loader = new \Example\Psr4AutoloaderClass; $loader->register(); $loader->addNamespace('setasign\FpdiPdfParser', 'path/to/src/'); If you do not have a PSR-4 autoloader class in use, just require the autoload file manually: require_once('path/to/src/autoload.php'); !! Always use the latest versions of both FPDI and the FPDI PDF-Parser !! !! and make sure that you do not mix the contents of both src/ folders !! FOR EVALUATION VERSIONS ONLY ++++++++++++++++++++++++++++ An evaluation package is encoded with Ioncube. This requires a loader to be installed on your server. An evaluation version is separated into two parts: The PHP files and a license file. License files are named .htFPDI_PDF-Parser.icl NOTICE THE DOT AT THE BEGINNING OF THE FILENAME! SOME SYSTEMS (MAC) AUTOMATICALLY HIDE SUCH FILES! The needed loaders and install instruction for the Ioncube Loader are available at: http://www.ioncube.com/loaders.php After the installation of the Ioncube Loader, place the license file into the /src directory or an upper folder of the FPDI PDF-Parser and follow the default installation instructions.