PDF version of PDF/X-2 standard for printing

PDF/X-2 is the most difficult, but probably the most useful, format in the PDF/X series. It is based on PDF/X-1a and PDF/X-3 and is compatible with both. It supports both CMYK data and tri-color advertising data with proper feature handling. In addition, it also literally added some "partial exchange" content.

The word "part" is easily ambiguous here. What it really means is that in a particular workflow, some or all of the referenced elements can be represented in a more logical form at the receiving site, or they can be exchanged at different times. These elements can be fonts, high-resolution continuous tone image files, or line graphics files. One of the difficulties is that in the document there is such a statement: "All the elements necessary for the final print copy can be included or uniquely specified." It is this "unique designation" that can easily cause problems.

The Committee considers that "only designation" is a necessary condition for the reliable exchange of data. The key to achieving the best balance between reliability, flexibility, and application complexity. Since the PDF/X-2 exchange determines that it requires the receiving and sending parties to exchange information (rather than unconditional exchanges) with respect to the file, even if flexibility is obtained, it will not be too much.

A very appropriate and difficult example is the problem of fonts. The various fonts used in the PDF/X-1 and PDF/X-3 requirements must be embedded, but some fonts do not allow embedding due to copyright issues (or some Asian character fonts cannot be embedded due to the large amount of data). PDF/X-2 does not require embedding but requires unique specification. But who can guarantee that the version of a certain font in both the sending and receiving documents of the document is absolutely the same? Even if it is the same, sometimes one of the parties will make subtle adjustments to the font's specifications. Most of the tools used to perform such inspection tasks are proprietary technologies that require authorization or payment to use. It may be a long way from regulating the use of this type of proprietary technology in the standard.
One solution that people are exploring is to provide a field that can be recognized by any font-checking software and can carry verification data for the various fonts used. Based on this, both the sending and receiving parties of the document have the responsibility to agree on the use of a particular piece of software, making them feel that the most reasonable balance has been made between reliability, flexibility, and the complexity of the application.

The selection of specific software can also be done by industry associations in specific industries, such as the American Press Association NAA. PDF/X-2 was jointly developed by CGATS and ISO/TC130. It is reported that it was established as a norm, rather than an international standard.

Source: China Automation Network