The Koninklijke Bibliotheek pays a great deal of attention to the quality of the digital images. The project is not just intended as a portal to large quantities of materials, but should also meet serious quality standards. When choosing the company to carry out the work, a careful survey was made of the quality the company could supply. These standards have been monitored carefully by performing (computerized) quality controls. Not only will this verify the correct number of files, the correct file names, the correct links between files, but also ascertain that the contents of files that have been delivered are correct and that they are technically correct.
Good quality images guarantee optimal optical character recognition (OCR). Character recognition is of the utmost importance given that it guarantees that the materials can be made available to the public as desired. The better the character recognition, the more information the website visitor will ultimately be able to find. OCR for the project Early Dutch Books Online had to address a number of specific problems. Examples are the spelling used in 1780-1800 and the use of specific characters such as the long S that looks like " f ". The software doesn't recognize this letter as "s" but reads an "f"