Wisdom of the PDF Sage

This post is for all those people who have avoided PDF because “if it’s not in XML, then it’s not good”, for those that think that Microsoft’s XPS is the “future of electronic paper”, and for those who won’t use anything not based on 100% OPEN STANDARDS…

Adobe announced today MARS - the Portable XML-based Document Format. The format that will give techno-geeks what they’ve been looking for in an electronic document format - based entirely on open standards.
Living inside of a ZIP archive is a collection of both custom and standard XML grammars (including a slightly extended SVG for page contents), standard image formats (JPEG, JP2K & PNG), font (Type 1, TrueType & OpenType), and other binary formats (ICC profiles, etc.).

BUT unlike some of the other options out there, it’s not just “electronic paper”! It has all of the interactive features that users of PDF have come to expect - forms, hyperlinks, annotations/markup, multimedia, etc.

Oh, and every copy of Acrobat AND Reader 8 will support it natively - just like they do with PDF today. No explict conversions necessary (unless that’s what you want to do).

Why would you use anything else?!?!

Hopefully this wets your appetite for MARS…and I plan to write more about it in the coming weeks.

NOTE: MARS is NOT a replacement for PDF - it is simply an alternative representation/serialization of the features and capabilities of PDF based on XML.

I got into a discussion/argument today in an online forum about the process of conversion of PDF->PS->PDF to help “clean up” PDF files. This process, called refrying is one that used to be quite popular - but since Acrobat 5.0 has been frowned upon by Adobe and others.The reason for this process being avoided is due to the wide variety of PDF features that can NOT be represented in Postscript.  Remember that the last update to Postscript (Level 3) was in 1997, while PDF has undergone 3 revisions (1.4, 1.5 & 1.6) since then - with 1.7 coming shortly with the release of Acrobat 8.
Here are a list of things that you might use in the content of a PDF that don’t translate well to PostScript

• Transparency
• ICC-based colors
• 16bit color
• JBIG2 compression
• JPEG2000 compression
• Layers (Optional Content Groups)

Also consider that any additional information added to PDFs during a PDF-based workflow (such as from Creo, Agfa, Quite, etc.) will be removed during the PDF->PS downgrading…

Of course, there is also the myriad of non-content elements that can be found in a PDF that don’t translate to Postscript/print, such as

• Hyperlinks
• Annotations, Commenting and Markup
• Forms
• Multimedia (movies, sounds, etc.)
• Bookmarks
• Metadata
• and more….

There are also concerns regarding fonts & text “searchability” that can be introduced into the refrying process DEPENDING on how the operation proceeds.  Differenet PDF->PS conversion tools, different OS platforms and even simply ‘printing to PS’ will produce wildly different Postscript output for the same PDF - thus producing wildly different output PDFs.

So in conclusion…

JUST SAY NO TO REFRYING