As you have seen throughout this book, PDF documents can be created and modified for a wide variety of uses. This inherent flexibility and specificity can result in a PDF being used for purposes other than the one for which it was originally intended. Preflighting allows you to check how well suited a PDF is for a particular use and in some cases correct some document problems without direct editing.
Acrobat 6 offers two tools for checking how accessible your PDF documents are for use by visually impaired users and for eBook use. These accessibility-checking tools can check document structure as well as document content. You can perform either a Quick Check or a Full Check.
Acrobat 6 allows you to run a Quick Check on the accessibility of your PDF. This check will look for document structure or the presence of tags. If tags are present, then your document will get a clean bill of health for basic accessibility.
Open the PDF document you would like to check for accessibility, and choose Advanced > Accessibility > Quick Check. Acrobat will tell you whether your document is tagged (Figure 11.1).
If your document does not contain structure tags, which are used by eBook readers to organize and deliver PDF contents, you have these choices:
You can add tags to your document so that its current structure can be automatically read, by selecting Advanced > Accessibility > Add Tags To Document.
You can, as the second Quick Check window above suggests, specify a reading order in the Reading Preferences: Acrobat/File > Preferences > Reading.
Or, you can do both. Try using the automatic ordering with the Add Tags To Document command, and if that does not provide you with the order you want, you can then go to plan B and override the automatic tagged order using the Reading Preferences.
If these options don t provide you with the reading order you want, you will have to manually edit the tag order. Chapter 12, Editing PDFs, for more information on editing tag order (that is, reflowing your PDF).
It is a good idea to always create tagged PDFs so that anyone who views your PDF will at least have the automatic tagged reader to use in case they want to view your PDF in an eBook reader or other device.
In addition to a simple document structure check provided by the Quick Check tool, Acrobat 6 provides a more thorough accessibility check. To run this check, open the PDF document you would like to check for accessibility and choose Advanced > Accessibility > Full Check. The Accessibility Full Check dialog appears (Figure 11.2).
Configure this window as follows :
Create Accessibility Report Browse to the location on your hard drive where you would like to have the accessibility option report placed.
Include Repair Hints In Accessibility Report Have the report include suggestions if you would like some tips on improving the accessibility.
Create Comments In Document In addition to a separate accessibility report, you can have Acrobat add comments to the document. (This is very handy!)
Page Range Select the PDF document pages you would like to test for accessibility.
A Full Check of a long document may take some time. If there are any pages that will not be included in the final PDF, you may want to exclude them from the Full Check process.
Checking Options Select the options for which you would like the Full Check process to examine and report. Unless you are very familiar with the accessibility items and know that you would like to exclude one or more, I suggest that you check all of these boxes.
When you re all set, click the Start Checking button to initiate the Full Check process. An HTML report will be generated (a sample named AmericanClassic.html is included in the Chapter 11 folder on the CD), containing the same included information and placed in the location you chose. You will also see a report on screen listing any accessibility problems found (Figure 11.3).
If you selected the Create Comments In Document check box, you can activate the Comments panel to view the location and description of all the accessibility report items (Figure 11.4).
The comments will show suggestions ”in addition to reporting problems ”if you have activated the Include Repair Hints In Accessibility Report option.
If the only thing that is necessary is for structure to be added to this document, then adding tags, as demonstrated earlier in this chapter, will fit the bill. Other corrections such as adding alternative text will require more extensive editing. the sections in Chapter 12 on the reflowing (changing reading order) of PDF contents and on adding alternative text to enhance accessibility.