Duff Johnson’s PDF Perspective

One of the new features in Acrobat 8.0 Professional garnering significant comment is redaction. This handy tool allowing users to permanently eliminate text or graphics from a PDF page. Solid, simple idea - what’s not to like?

Thus far, Acrobat 8’s redaction tool has been generally well received in principle, although a few discriminating reviewers have also noted a key concern with the method Adobe chose for redaction in Acrobat 8.0, as we shall see.

Acrobat 8 Professional is the first Adobe software to include a redaction feature for PDF, but it’s not the first. Acting on a request from Adobe, in 1996, Appligent developed and released the first version of Redax, which quickly became the definitive tool for serious redaction work on PDF files. The latest version of Appligent’s Redax works with Acrobat Standard and Professional versions 6, 7 and 8.  So you don’t need to upgrade to Acrobat 8 Professional to get PDF redaction.

To help me evaluate Acrobat 8 Pro’s new redaction tool, I wanted to find out more about how people use (or fail to use) the one PDF redaction tool that’s been available for over 10 years. I talked to Mark Gavin, founder and CTO of Appligent, to get his take. I began by asking Mark to explain the basic difference in the way Redax and Acrobat redact PDF. The answer was illuminating.

“There are two primary differences between Adobe’s redaction and Appligent’s redaction,” Gavin says. “Appligent uses an “additive” redaction methodology while Adobe uses a “subtractive” redaction methodology.”

OK, sounds technical… but redaction is redaction, right? Who cares how you zap it? This is where Gavin set me straight.

“Adobe takes an existing document and attempts to remove or “subtract” information,” says Gavin. “Appligent creates a new blank document and then “adds” the non-redacted information into the new document. Thus, the new document has never been touched by the information to be redacted.”

So, why does this matter?

Although Acrobat redacts the way you might intuitively expect (subtraction), this method is flawed. As I saw for myself almost as soon as I started redacting with Acrobat 8 Pro, I managed to “nuke” my original document by carelessly doing something that’s routine for me in other document workflows - a “Save As” operation in which I over-write my original file before I’d even realized what I was doing.  I’m not exactly the average user, so this got me thinking.

Someone who makes this mistake while redacting in Acrobat 8 Pro, will be running for the backup tapes - if there are any. Once redacted, that data is GONE. That’s a pretty harsh penalty for a easy fumble with a single keystroke. Redax’s redaction method, by contrast, makes it pretty much impossible to damage the original document.

The problem arises because Acrobat merely offers the user a ‘Save As” opportunity rather than assuming that the redacted file must be, of necessity, a new version of the document… a redacted version.  Inattentive users and system crashes are known threats  to be engineered around.  In principle, no redaction workflow should EVER put the original document at risk.

Gavin went on to explain that Acrobat’s method forces the application (and the user) to locate and remove all of the document metadata with an extra step, even custom metadata that Acrobat knows nothing about. Since Redax creates a new blank document, the only information retained is that specifically requested by the user - the text and metadata they affirmatively chose NOT to redact.

The second major difference between Acrobat and Redax, according to Gavin, is that Redax is designed to redact in a “fail safe” manner where Acrobat is not.

“If for whatever reason the document is not redacted correctly, this must be made very clear to the user that something is wrong,” Gavin says. “One of the techniques Redax employs to ensure fail safe operation is to use transparent zones to identify redaction areas. If any text or graphics remains in the redacted document it can easily be seen by the end user. On the other hand, Acrobat’s redaction zones are completely opaque. Since on occasion the Adobe software will fail to redact all the information correctly, the user won’t be able to easily see that information has been left behind.”

For these reasons, I cannot as yet recommend Acrobat’s redaction, free as it is (with the purchase price of Acrobat 8 Pro), over the fail safe and time-tested Redax.

This post is part of a series based on the “Extended Rights Manifesto“. See this post for some context.

Changes in Acrobat 8

Acrobat 8 Professional now offers three ways to “bless” a PDF with Extended Rights (”Reader-Enable”):

1. From the Advanced menu, simply select “Enable Usage Rights in Adobe Reader” to bless your PDF with Forms Save, Commenting and Digital Signatures rights. Forms-data import and export rights are also enabled (although undocumented). However, the right to spawn new pages from templates in Reader is unavailable in Acrobat 8 Professional, as is SOAP, or the capacity to bless more than one file at a time. See this post on Thom’s blog and this article by Ted Padova for more specifics.
2. “Distribute form”, available on the Forms menu or task button is a simple wizard that adds Extended Rights within a canned distribution model based on your email client.
3. “Send for Email Review” from the Comments menu or Review & Comment task button calls a wizard which adds Extended Rights for commenting only, disabling any Extended Rights.

Comment

First and foremost, Adobe deserves a lot of praise for taking the risk of moving formerly hyper-expensive “enterprise” functionality right into the desktop mainstream at a “mere” $449 a pop. What’s the catch, right? And for that matter, what’s the point of Adobe’s LiveCycle Reader Extensions Server now?

The “value add” of the Reader Extensions Server has been amended to:

1. Enabling the right of PDF files open in Reader to spawn new pages (as may be called for in on-board javascript)
2. Enabling SOAP rights (connecting PDFs to live content delivered by a webserver)
3. “Blessing” PDFs via the Batch Processor
4. And of course, everyone’s favorite: “because the End User Licence Agreement (EULA) Says So”.

Now… I’m not actually having much luck actually FINDING the EULA text anywhere in the Acrobat documentation post-installation, nor is it up on adobe.com as of this post. So the only chance you have to read it in the short-term is if you pay attention during the customary “click though” moment on installation when you are asked to accept a software licence. This time, don’t just click though, as I did.

In any event. If memory serves, the EULA limits users to either 500 end-users per form, with unlimited “instances” of the forms for each user…. or else distribution to an unknown number of users (ie, posting on a website) with a limit of 500 form-instances collected. How you figure out when you hit these limits is (it seems) up to you.

(…)

You might very well think that, but I couldn’t possibly comment.

The Manifesto Score Card, Article 1

November, 2006, Acrobat Professional 8.0: 8 out of 10.

The lack of the template spawning and SOAP “rights” is a real shame, and it should be possible to batch enable forms. There’s something wrong with the business model when people aren’t being encouraged to use this extraordinary functionality as much as possible. We also need more control over the messages displayed (or not) to the user when they open PDFs with Extended Rights, but these are whines about the way Rights are handled, not the Rights themselves. Even the LiveCycle server product doesn’t include (via the UI, anyhow) enough “controls” over the way Extended Rights actually manifest in PDF.

(An aside, I recently needed Extended Rights on a “kiosk” type project… not to actually allow Reader to Save, but simply to stop the !*&!@#$% warning message about how Reader “couldn’t save this form” from appearing everytime users touched a form-field!)

I also have a caveat on the EULA. Adobe’s real intent is clearly (a) lax and (b) TBD, but what bothers me more is that the idea seems kind of goofy; a barrier to business at best, a missed opportunity on the revenue side (tsk, tsk) at worst.

But that’s for another post.

Nonetheless, the simple fact is that allowing Acrobat 8 Professional to “bless” a PDF, any PDF, with most available Extended Rights, is a marvellous thing. Whole workflows can now blossom in PDF. It’s a $449 bargain based on this feature alone. Reader can Save! If you’ve bothered to read this far, you know what that means.

More Articles to follow over the next few months.

Interested in accessibility for electronic content like PDF, Flash, movies, podcasts, etc?  If you are in the publishing or government sectors, you should be.

Joe Clark’s new Open and Closed Project plans to write a set of standards for the four fields of accessible media – captioning, audio description, subtitling, and dubbing. 

Who is Joe Clark?  Author, consultant, captioning guru, WCAG gadfly, active PDF/UA member and generally all-around intellectual warhead, Joe is exactly the kind of smart and fastidious purist who just might do a GREAT job doing exactly what he says he’s going to do.

In his own inimitable and irreverent way, Joe needs your help, or more specifically, your patronage (as he puts it).  He’s set up the Joe Clark MicroPatronage Project, where you can help fund Joe’s work on the Open and Closed Project.

As chair of PDF/UA, an AIIM Standards Committee in which Joe has participated for two years, I can personally attest to Joe’s… uh… forthrightness, dedication to purpose and capacity to contribute.  He’s both intellectually vigorous and rigorous, and his research is very likely to be not only interesting, but of real value to those in the field.

So, go ahead!  Make a deposit in the Karma Bank, and let’s see what Joe comes up with!

The single most important feature of Acrobat Professional 8 is a dramatic expansion in the Reader Extensions that Acrobat Professional may apply to PDF files, bestowing new “Extended Rights”. Of these, the most important such “Right” is commonly known as “Reader Save”. Within the new End User Licence Agreement (EULA) and certain other technical limitations, Acrobat Professional 8 obviates the need for expensive servers, programmatic chicanery or 3rd party products to deploy this key feature for end-users.

Simply put, Reader Save allows an Acrobat Pro user to “bless” a PDF such that form-fields may be completed and then saved by any user with the free Adobe Reader. This facility is a desirable quality for almost any fillable form, and in many cases, it is simply essential in many of the form workflows actually operating in the real world.

Before Acrobat 8, the only way to get this feature into a PDF was via Adobe’s Reader Extensions Server (ARES), five-figure “enterprise” software sold exclusively through Adobe’s direct-sales bureaucracy. ARES remains a product in Adobe’s LiveCycle lineup - more on that later.

In July, 2006, I introduced the Extended Rights Manifesto; essentially, a set of checkpoints for assessing the implementation of Reader Extensions in Adobe’s PDF management software. The idea was to offer encouragement and guidance to Adobe Systems as they pondered their strategy for moving Reader Extensions to Acrobat Professional.

In forthcoming posts, I’m going to go through the Articles of the Manifesto one by one, and “score” Adobe on the new playing field they’ve created with Acrobat 8. At the same time, we’ll doubtless think of some revisions to the Manifesto, in fact, we’ll need a whole NEW Manifesto just to keep up. Stay tuned! Along the way, please feel free to let me know YOUR thoughts on Extended Rights as well!