by Duff Johnson
Originally appeared in:
Even without ISO recognition, PDF stands as today's de facto standard for final-form electronic documents. Trust is a precious commodity, and Adobe's PDF has earned the trust of computer users everywhere for consistency, reliability, ubiquity and relative safety.
Like Microsoft's Office, PDF and the Adobe Reader are deeply embedded in the fabric of the desktop computing experience. Also like Office, PDF's present-day dominance generates concerns over proprietary technology. Such concerns are accurately regarded by Adobe as retarding official recognition and adoption of PDF, and at a sensitive time. Just in December, 2006, Microsoft obtained ECMA approval for their massive and much-criticized OOXML specification for Microsoft's Office applications (and little else), now headed for ISO.
In the previous article, I pointed out that Adobe's early choice to publish the PDF Reference was a major factor in the format's climb to this justifiably proud status. The notable downside was early industry adoption of an imprecise, incomplete Reference document. This spawned a major problem (which continues to this day): the lack of any real conception (programmatic or otherwise) of what constitutes "valid" PDF.
Millions of PDF files are created around the world everyday. The results from a large fraction of these PDF creation events isn't going to meet any likely ISO-PDF Standard anytime soon, yet most of these same files represent "good faith" executions of the PDF Reference - one way or another.
This article reflects some conversations on these matters with a few 3rd party industry heavyweights, the sort of people who will sit on AIIM's PDF committee alongside Adobe's own representatives.
Let's get one thing clear up-front: I work with, listen to and learn from a wide variety of software developers, but I'm not one myself. I'm a customer. I use, complain about and (occasionally) commend the tools developers build. Some of my best friends (as the saying goes) are software developers, very good ones, in fact. Many are specialists with PDF.
When asked, they agreed that the style and structure of the current PDF Reference simply isn't ready for ISO as-is. As noted earlier, today's PDF Reference isn't written in the typical language of ISO Standards. The Reference makes no differentiation between normative requirements, recommendations and statements of current practice in Adobe's Acrobat tool. It's hard to see how one gets PDF to an ISO Standard without undertaking quite a bit of this rather heavy lifting.
The current ISO PDF Standards, PDF/X and PDF/A, are both under 30 pages. Both address highly focused subsets of the 1,300-page PDF Reference 1.7. The ISO PDF project will dwarf those "miniStandards".
The necessary task of editing the PDF Reference in the timeframe Adobe envisions (12-30 months) seems likely to mean full time work for a small group of highly talented people. Will Adobe dedicate these resources? If it does, will anyone else be able to dedicate the resources necessary to keep up with them? But perhaps these are boring practical considerations. Let's look at the hummer.
The earlier iterations of the Reference were (to be plain) short and loose. Even the current 1.7 version Adobe is taking to ISO contains many ambiguities. Yet since it published the PDF Reference for anyone to use, Adobe bound itself to respect as many of the possible ways a PDF could be (mal)formed. And they are legion.
In the very, very beginning, Adobe charged USD$50 for the Acrobat Reader instead of giving it away. Had it retained that strategy, the company wouldn't exist on the business desktop today. The decision to make Reader both free and freely distributable has played perhaps the single most significant role in the success of the PDF format, and of Adobe Systems itself.
Apart from being free, Adobe deliberately made Reader rugged enough to open almost any PDF file, regardless of how corrupt. It had to. Remember, the Reference gave (gives) few rules for building PDF files. Mainly, it offers just the "pdf building" vocabulary itself. When Adobe released the Reference it set itself up for a tidal wave of dubious PDFs, and not only from third parties. Modern document authoring software offers users so many possibilities that Adobe's own PDF creation software itself often doesn't know exactly what to do.
In an important sense, then, it is wrong to say that PDF is the de facto standard. "The de facto standard for PDF validation is Adobe Reader," says Appligent's CTO, Mark Gavin. "Unfortunately, Adobe Reader is not, and never was intended to be, a validation tool."
Adobe makes Reader do the software equivalent of a triple back-flip to ensure that the application will open pretty much anything it's asked to open. That is why Reader is a relatively large and resource-intensive application compared to "alternative" free PDF viewers such as Foxit. Those applications don't even try to open any heap of bytes with a .pdf extension, but Reader does.
Adobe had realized that compatibility is far more important than formal compliance. Since in the early days the company still needed to evolve the Reference, Adobe made compatibility a matter for the Reader, NOT a matter of the Reference. As a result, the company now finds itself propping up a legacy of rock-solid support for old and vague documentation. As a result, Adobe maintains a zero-revenue Reader that chugs while the rest of the industry enjoys gets a free lunch while looking forward to a free dinner -- Adobe's continued expenditure on developing new features for the PDF Reference.
Adobe has never released a "PDF Validator", a tool to document compliance or deviation from an "ideal" PDF. If a PDF Standard is to mean anything, it would mean that a validation tool could be built by someone other than Adobe Systems. But it wouldn't be welcomed everywhere.
Martin Bailey, CTO of Global Graphics says: "If [Adobe] brought out a genuine validation tool today the howls of protest from third-party vendors, their customers (and probably Adobe's CS team!) would be extremely painful, even if it strengthened PDF and its associated ecosystem in the longer term."
I wonder. How better to get the painful moves accomplished than by tossing the issue into a Committee? For Adobe, the trauma to third parties and their customers will all be defensible. After all, the Committee is responsible for the Standard that begets the Validation Tool, not Adobe. Moreover, the Committee's work is very much in the long-term interest of consumers. It's the classic "price of progress".
Stephan Jaeggi, co-author of PDF/X-3 and Technical Officer of the Ghent PDF Workgroup, welcomes Adobe's intention to submit PDF to ISO. "This gives all existing and developing standards based on PDF like PDF/A, PDF/X, PDF/E and PDF/UA a more stable base." Jaeggi says. "On the other hand it will certainly slow down the development of PDF."
Martin Bailey agrees, and concluded our discussion with the following thought: "There are clear reasons why Adobe has to take PDF into the standards arena, and clear benefits for users and vendors alike. On the other hand I'll be interested to see how the time-scales of iterative standards development interact with development of new versions of Adobe's PDF-based products; that's going to be a fascinating planning process for all of us."
Indeed!
Sarah Rosenbaum, Adobe Systems' Director of Product Management, graciously agreed to answer a few questions on short notice.
Q: Is Adobe basically "done" with the PDF Reference?
A: Adobe will continue to innovate and grow the PDF file format, with the added benefit of stakeholder input via the standards organization.
Acrobat and LiveCycle are important businesses for Adobe, and PDF will continue to evolve through our ongoing investment in innovation as demonstrated by PDF 1.7. Adobe stewarded the PDF specification since 1993, evolving the PDF file format based on customer needs and Adobe will continue to do so in the future. The PDF Reference will continue to be available as it is now until the full PDF 1.7 specification has been fully ratified by ISO. At that time, ISO and the organizations working towards the PDF standard effort will determine where and how the PDF Reference will be accessible and amended.
Q: Adobe's FAQ states: "New features and changes to PDF...will be developed within ISO." How will Adobe handle updates to PDF outside of ISO, if any? Will there be an ISO PDF and an Adobe PDF, or an ISO PDF with Adobe Extensions?
A: Once ratified as an international standard, all updates to PDF will be stewarded entirely by ISO. Adobe plans to participate on the technical committee. Just as Adobe does with other standards, the company evaluates new features and includes them in its products as it makes sense according to the objectives established by our product teams. Adobe may include features in upcoming products that are not in the PDF standard.
Q: Does Adobe envision a day when the "mainstream" Reader will only support ISO Specification PDFs? What about Standard or Professional?
A: One of the great features of Adobe Reader and Acrobat is that they are backwards compatible with regards to opening PDF files. You can open PDF files created with the latest Acrobat 8 software and PDF files created with the first version of Acrobat, as well as those created by third-party vendors. We don't envision a time that there will be a version of Reader and Acrobat that only open the ISO standard of PDF.
Similar to how Reader and Acrobat can now open PDF/A and PDF/X (ISO standards), the proposed ISO standards PDF/E and PDF/UA, as well PDF files that aren't ratified standards and those from third-party vendors.
Q: Will Adobe release, co-develop or otherwise sanction an ISO PDF Validation Tool, and release a set of validated test files for the first draft of the ISO Specification?
A: Adobe will work in conjunction with AIIM and the ISO working group on the standards process. All tools and test files will be coordinated within the guidelines set forth by the standards committee.
Q: Adobe's FAQ states that Adobe will submit the "full PDF 1.7 Specification" to AIIM. Are there any exceptions, for example, 3D?
A: The PDF 1.7 specification that is posted to Adobe.com and was referenced in the press release is what is being submitted to AIIM. Everything in that document is included in what is being submitted.
There is certain functionality referenced by the PDF file format that isn't being released to ISO for standardization. Additionally, there are several other specifications that PDF employs, such as XML Forms Architecture (XFA) and JPEG (image file format) that are under the control of other standards organizations.
Unsolicited advice is rarely well-received, just as few good deeds go unpunished. Offering one's precious technology to a Standards Committee is one surefire way of becoming a punching bag, as Bob Sutor has ably demonstrated to Microsoft's grief. Offering considered advice to a major corporation (and occasional consulting client) in public is a good way to get frozen out! Nonetheless, the announcement was made, so this seems like the time. If Adobe were to ask my opinion today, this is what I would say:
- It appears some work is required before 1.7 can realistically become a Standard. Accept that, then dedicate substantial writing, deep technical and other resources to supporting and expediting a rigorous Standards process. The whole industry, regulators and customers will applaud.
- Commit to synchronizing Adobe products to the ISO PDF Specification. Is it desirable or even healthy to think in terms of "getting in front of" the Standard? After all, Adobe still has Reader with which to leverage revenue-generating products. Making this commitment will clarify and reinforce the future of PDF.
- Focus on products! There is so much more to be done with Acrobat and related software, even if PDF itself stayed at 1.7 for years to come.
Originally posted on planetpdf.com
