FEBRUARY 2007

PDF Bookmarks: Surveying the options

by Duff Johnson, CEO, Document Solutions, Inc.

Introduction

What are bookmarks? We’re not talking about strips of cardboard or dog-eared pages. When present, PDF bookmarks appear to the left of the page (the F4 key toggles the bookmarks “panel” on and off). In the most common application, bookmarks allow users to instantly skip to other locations in the document. That's VERY handy, especially for longer documents.

Bookmarks are most typically employed as a clickable table of contents. Unlike a table of contents, which exists as a page within the document, bookmarks remain on screen as long as you need them. Transporting the user to any desired heading within one or more PDF documents, bookmarks may also trigger almost any other action available in PDF, such as a link to another website, JavaScript code, a “Print” command and so on.

Often, bookmarks are the very first interactive feature users want to see in a PDF file. The all-too common lack of bookmarks is a simple explanation for most of usability guru Jakob Nielsen’s famous gripes about PDF. Without bookmarks, finding a specific subheading in a PDF file a mere 10 pages in length can be a minor exercise in frustration, even for advanced users. If the PDF is very long, or serves a reference document where swift access to any subsection is at a premium, frustration can quickly grow. The real value of bookmarks for everyday document navigation is illustrated in Bookmarks: Why and How.

In addition to document-navigation needs, bookmarks deliver other advanced functionality through a smooth, consistent, omnipresent and therefore familiar interface. Beyond hierarchical tables of contents, bookmarks can easily unify navigation among multiple PDFs into a single, simple interface, provide a index of tables, figures, part numbers and so on. Bookmarks have even been used as triggers for audio commentary. Some authors dispense with the toolbar altogether, opting to offer bookmarks as the ONLY interface for the functions they consider desirable. The possibilities are almost endless.

The best possible place and time to create PDF bookmarks is when authoring the document. Those with PDF-aware applications, such as Adobe InDesign or Adobe FrameMaker, have the most control, and may use elements such as headings, tables and other structural features to create their bookmarks. For most of the rest of us, consistent authoring practices in Microsoft Word, along with Adobe Acrobat's PDFMaker, can generate complete, high-quality navigational bookmarks in PDF files directly from the word processing application.

Most PDF files do not include bookmarks. This is a pity, because they are so easy to add, and because the real-world usability of longer PDF files suffers significantly by their absence. The effort involved in bookmarking is properly regarded as a capital expense, enjoying a sustained payoff over the lifetime of the file in terms of reduced time required for searches, reduced print costs (people are less included to print PDFs they can quickly navigate on screen) and happier, less frustrated users.

Some organizations have found bookmarks powerful enough to build significant document workflows around this simple feature — archiving email, invoices and other naturally “meta-structured” content) with the simplest of solutions.

In this article, we’ll quickly review navigational PDF bookmarking in Acrobat before surveying the range of third-party tools for automatically creating and managing this stand-out feature for real-world PDF usage.

The tools

Most PDF documents aren’t properly tagged – and good tagging makes bookmark creation push-button easy in Acrobat Professional. Automated bookmark creation on untagged or poorly tagged PDF files presents a number of difficulties. Many PDFs aren’t fully consistent in terms of font usage, heading styles, text colors and so on, and it is these sorts of cues that auto-bookmarking software uses to understand a document’s structure. There are other challenges as well, including multi-line headings, font encoding, multi-column pages, section enumeration, actual page vs. pagination considerations, and a variety of other cases that defy attempts to automatically generate clean, functional bookmarks.

The upshot is that none of the tools listed may be counted upon to work in all situations. PDFs are just too variable – may be authored in any number of non-standard ways that defy the automation. For these files, there is always manual bookmarking of your PDFs, and it's not as bad as you think!

Adobe Acrobat

Acrobat Standard and Professional provide three basic methods for the creation of navigational bookmarks, summarized as follows: Bookmarks from Office, Bookmarks from structure and manual bookmarking.

Bookmarks from Office

One isn’t in Acrobat per se at all, it’s the “MakePDF” plug-in Acrobat installs into Office. MakePDF converts a well-structured Word or Excel file to PDF with Headings and/or Styles delivered as bookmarks.

To get bookmarking with PDFMaker, look in your Office toolbar for “Adobe PDF.” Click Change Conversion Settings at the bottom of the menu, then click Add bookmarks to Adobe PDF.

You then need to check the Bookmarks tab to ensure that the styles you’re using in your Word file will be correctly represented in PDF.

This approach is, in a sense, ideal, because changes to the original document need not force the user to re-create the bookmarks as a separate operation to creating a new PDF. However, in order to get good results, it is vital to ensure that your Word file is properly structured, with consistent usage of headings or styles.

Note: In Outlook, MakePDF uses e-mail header information to generate superb e-mail archives, comprehensively organized using bookmarks. I vastly prefer this archiving method to Outlook’s.

Bookmarks from structure

Acrobat Professional allows the user to tag the content in PDF files for enhanced accessibility and compliance with Section 508. Once tagged, bookmarks for these files may be generated from the tag structure.

To bookmark from structure effectively, you’ll need to ensure that your tags are set up just the same way you want your document to be bookmarked, including consistent tagging of heading levels and whatever else you want to bookmark.

Manual bookmarking

Finally, Acrobat facilitates bookmark creation through a manual process. Sometimes this is the only way to automatically bookmark PDFs, for example, if the PDF is a set of photos. Open your PDF and visit the page and zoom level (Fit Width, for example) that you’d like to see as the target of your bookmark. Select the text (usually a heading) that you’d like to see become bookmark text, and press Control-B. That’s it!

ARTS PDF Aerialist

Aerialist is a venerable plug-in for either Acrobat Standard or Professional, and counts dexterous bookmarking tools among a wide variety of PDF-management features.

Key Aerialist features include:

• Split files by bookmark and bookmark level (and combine files, including the bookmarks)
• Export bookmarks from the open file, which may then be imported into any other PDF
• Import bookmarks from a simple-to-create database
• Find and replace text, text attributes and even functions from the contents of the Bookmarks pane. These find/replace operations may be performed with advanced text masking as well
• Building multi-level bookmarks based on font attributes (text size and color), the presence (or absence) of keywords, and many other specifics
• Allowance for variations in font size when building bookmarks. This detail is exceptionally helpful when documents are imperfectly authored and inconsistent
• The ability to make most of the above functions operate via a batch process

We find Aerialist easy to use and reasonably reliable. Far more than bookmarking, the product offers a broad menu of PDF-management tools that extend or enhance the Acrobat application in many ways. The Build Bookmarks engine is particularly effective and flexible. This tool is not as comprehensive for strictly bookmarking purposes as ISI's Toolbox, but it is far easier to learn and offers a lot more than just bookmarking. Highly recommended.

EverMap AutoBookmark

Unlike Aerialist, Evermap’s offering is directed at bookmarking only – this program does nothing else. However, it does do navigational bookmarks very well, with detailed bookmark-creation options and subtle features rivaled only by ISIToolBox.

EverMap’s advanced bookmark generation goes beyond font matching. AutoBookmarker includes the ability to process a range of pages, to match case, and allows users to find and replace text in the bookmarks on creation (useful for text-encoding errors), to changing text case for bookmarks (VERY valuable) and to remove duplicate spaces and hyphens.

Once you’ve built your bookmarks, AutoBookmark helps you check and manage them with a clean, intuitive interface. From bookmark validation (including links to the Internet), to text-pattern matching and bookmark text and case management, this application has automated navigational bookmarking wrapped up. You can even set custom bookmark colors and typefaces based on the bookmark level. Users can export bookmarks to text or XML, and even print the bookmarks themselves, or print only bookmarked pages. The range of capabilities for developing, managing and quality controlling PDF bookmarks is very impressive.

Image Solutions Compose

Compose was originally created by InfoData, and is now maintained and sold by ISI. More expensive than Aerialist, the current release of Compose has actually been around for a few years, and like Aerialist, includes many non-bookmarking tools. On bookmarks, it does offer a few tweaks that Aerialist does not, but lacks other powerful features such as bookmark-by-keyword and the ability to import and export bookmarks.

Compose’s Bookmarks by Example, relies on font, text size and other characteristics, and is analogous to Aerialist’s Build Bookmarks function.

Aerialist and Compose contain very similar bookmark-building functionality. Each has an edge over the other in different ways. Compose, for example, allows the user to match text based on the font root rather than an exact font, as well as on typeface style (italics and boldface), something Aerialist does not offer. Aerialist allows you to bookmark (or exclude from bookmarking) based on a keyword list and handles multi-line headings with aplomb. You should be able to get a good idea from the documentation which application meets your specific needs.

Compose also includes the Bookmark and Link Manager that facilitates management and correction of wayward bookmarks, and the valuable Auditor, which reports on invalid GoToView and OpenFile bookmarks, plus a report engine.

Image Solutions ISIToolBox Professional

Before it acquired Compose, Image Solutions developed ISIToolbox Professional. In some ways, this tool really has it all, with settings and options too numerous to detail here. Almost any way you can think of to bookmark PDFs, this tool has you covered.

The pharmaceutical industry deals in some of the largest individual PDF documents in existence. ISIToolbox was designed with drug and clinical trial documentation in mind, and functions such as the Bookmark Master are organized around predictable requirements for medical-trials documentation.

Another tool that was developed specifically for FDA submission requirements is also useful to other document developers. The AutoReturn Bookmark tool gives users a powerful way to add inter-document bookmarks throughout a collection.

The TOC/Bookmarks tool is uniquely functional. Users can simply zone the Table of Contents in their document and in many cases see a fully functional set of bookmarks matching the Table of Contents. Best of all, this tool is fast, especially compared to some of the others. ToolBox also includes a solid validator to report on and check destinations for links and bookmarks.

When Bookmarking via fonts, ToolBox Professional does not include an option for allowing variations in font size – a characteristic of real-world documents authored by non-experts, or outside of templates.

Setting an exclusion area on pages processed is another neat feature, allowing the user to eliminate page headers or footers from bookmark processing. This feature is essential when you must bookmark by font on documents that happen to use similar fonts in both document headings and page headers or footers.

KAPSware BMK Bookmarker

KAPS offers bookmark management tools in a combination of plug-ins and stand-alone applications. The two basic modules are the Interactive and Audit Modes.

Before entering Interactive mode (where users set up their bookmarking), BMK must shut down Acrobat before re-opening with a stripped-down interface. I wonder why they bothered. Many of BMK’s manual PDF-bookmarking functions are largely recreations of the core manual bookmark-management functionality available in Acrobat itself.

BMK does offer both standard and sophisticated bookmark automation features and validation, albeit in an overly complicated and unintuitive interface. To us, the program appeared significantly unstable, and crashes (in my experience) required a complete restart. Batch operations (the major selling point in the Application Suite version) seem a tad optimistic in the application’s current iteration.

KAPSware’s “Lite” BMK tool, however, runs purely as an Acrobat plug-in and has most of the relevant features found in the Suite version. We found it more stable as well.

Mapsoft Bookmarker

A simple plug-in, Mapsoft’s Bookmarker offers a single, clear dialog with most of the options required for basic bookmarking of structured documents. There’s one important option shared only by the far more expensive ISIToolbox: the ability to ignore page margins.

While basic, this plug-in is a highly functional auto-bookmarking tool. There’s no validation, text matching or case management either. But if you want your document bookmarked exactly as the headings appear, this little plug-in can do the trick.

Auto-Bookmarking Comparison Matrix

« = Poor ««««« = Stellar

NOTE: All products listed require Adobe Acrobat Standard or Professional. All evaluations were conducted in 2006 using then-available versions trial versions. Products marked with an * provide bookmarking features ONLY. All other products provide additional features.

Company	Product	Auto-Bookmarking Power/Flexibility	Ease of Use	Stability/ Reliability
Adobe Systems	Acrobat 7.0x (w/tags)	• •	• •	• •
Adobe Systems	Acrobat 7.0x (MakePDF)	• •	• • • •	• • •
ARTS PDF	Aerialist	• • • •	• • • •	• • • •
Evermap	AutoBookmark*	• • • •	• • • •	• • • •
Image Solutions	Compose	• • • •	• • •	• • •
Image Solutions	ISIToolbox Professional	• • • • •	• •	• • • •
KAPSware	BMK*	• • •	• •	• •
Mapsoft	Bookmarker*	• •	• • • • •	• • • • •

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