Normalized PDF

A Normalized PDF may have External references, a different color space, Document level metadata, and Object level metadata from a generic PDF document. A Normalized PDF is not always self-contained. It can refer to images or other PDFs that are not embedded in the PDF itself. To guarantee that a PDF can be processed correctly by PDF application (like Adobe Acrobat) it has to be made self-contained.

A Normalized PDF can only contain objects in the final printing color space. The PDF object model allows objects to be defined in RGB and CIE based color spaces. This is not possible in Normalized PDF. During normalization such objects are color converted to CMYK.

A Normalized PDF contains Document level metadata called XMP metadata. The schema of the XMP data is proprietary, but the specification is public. The XMP metadata contains info about the file that can be extracted by 3th party applications.

A Normalized PDF contains Object level metadata or specific objects like barcodes. Object level metadata are stored using a proprietary mechanism and format.