Jan 252013

Cleaning up the order of a tag tree in a lengthy PDF or the item list in structure tree of an InDesign file can be a time consuming job, particularly if there are a number of graphic objects in the file. InDesign places objects in the structure in their order of creation. In most cases, graphic items aren’t added to the file until after the main body of the text has been flowed. This places the graphic objects at the end of the structure, and they must be moved to their correct locations to end up with a compliant tag tree in the PDF.

Anchoring your graphics to their correct text locations substantially simplifies this process. Starting with InDesign CS5.5, Adobe has made frame anchoring much simpler than the convoluted process you had to go through in previous versions in order to anchor frames.

All non-linked frames and grouped frames now have a blue handle on the top right side. Simply dragging this handle to the correct text location anchors the frame to that location. When you export the tagged PDF from the InDesign file, the graphic shows up in the correct location in the tag tree.

There are some things you need to consider when placing these anchors:

  • Since the graphic will likely have alternate text that will be read when the text reader reaches the graphic, you should place the graphic where the alternate text will not disrupt the logical flow of the text. For instance, if there is a call out for a figure in the middle of a sentence, you probably would not want alternate text read until the end of the sentence. You would likely place the anchor point at the end of the sentence or the end of the paragraph.
  • The anchor point needs to be placed on the same page as the location of the graphic. This means that if a call-out is on a page preceding or following the page the graphic is on, you will need to anchor to some logical point on the same page as the graphic. If there is no text to anchor to on the page with the graphic, then you cannot anchor the frame.
  • It is not unusual to receive files where separate frames containing the title of a graphic, the graphic itself, and notes following the graphic are all grouped together. Before anchoring a graphic, the individual frames need to be ungrouped if you want a text reader to read the title and notes. You can then anchor each one of the frames containing the title, the graphic, and the notes to the same location in their proper order. If you leave the items grouped, you end up with one figure item in the PDF’s tag tree. The title and notes are not available to be read by the text reader.



Jan 252013

There are a variety of ways of adding alternate text to your InDesign source files.

  • Importing a graphic into InDesign with alternate text already added
  • Adding alternate text to an imported graphic by adding an Alt or ActualText attribute to an item in the Structure pane
  • Starting with InDesign CS5.5, adding alternate text to a graphic frame, text frame, or a group using Object Export Options


Importing graphics containing alternate text

Graphics can be created in a variety of programs, many of which allow you to add XMP metadata about the graphic. Similarly, many image editing programs also allow you to enter XMP metadata to the image or edit metadata that has already been added such as data added by digital cameras. When graphics and images are imported into InDesign, their metadata is retained and is available to be used as Alt or ActualText attributes when the InDesign document is exported as a tagged PDF. How the XMP metadata is accessed is discussed under the section below concerning using Object Export Options.

Additionally, MS Word allows you to add alternate text to graphics which in turn can be imported into InDesign and used as an Alt attributed when exported as a tagged PDF.

When imported into InDesign as a linked file, certain files can be opened in Adobe Bridge which can be used to add or edit XMP metadata. If linked files are updated in Adobe Bridge, InDesign will indicate that the linked file should be updated.

Adding alternate text to elements in the Structure pane

When working with elements in the Structure pane, you can add or edit Alt or ActualText attributes. Elements are items in a document that have been marked with XML tags.

If you haven’t worked with the Structure pane before, you open the pane by selecting Structure > Show Structure from the View menu. If you have not added elements to the Structure, all that will show in the Structure pane is Root element. Add items to the Structure by selecting Add Untagged Items from the Structure pane menu. To add an attribute to an item, select the item, then either click the Add An Attribute button, choose New Attribute from the Structure pane menu, or right-click the selected element and choose New Attribute.

When the attribute dialog opens, specify a name (either Alt or ActualText) and a value, the alternate text. Note that the name is case sensitive. The attribute will be exported as alternate text when you create a tagged PDF from the InDesign source file.

Adding alternate text using Object Export Options

Starting with InDesign CS5.5, Adobe has added an alternative to adding alternate text in the Structure pane. You can now add alternate text to graphic and text frames in the document by selecting the frame and opening the Object Export Options dialog from the Object menu.

With the Object Export Options dialog open, you are presented with the following options:

Alt-Text options

  • Custom – Enter the alternative text manually
  • From Structure – Uses text specified as an attribute in the structure
  • From XMP – Uses data stored in the file as XMP metadata in one of 3 locations that you specify: Title, Description, or Headline
  • From Other XMP – Uses data stored in some other XMP metadata field which you specify with the namespace and property name.

Tagged PDF Options

Apply Tag

  • From Structure – Uses tag specified in the structure
  • Artifact – Use for graphic elements that you do not want read by a screen reader
  • Based on Object – Automatically determines whether the tag should be either “Story” or “Figure.”

Actual Text Source

  • Custom – Enter text manually
  • From Structure – Uses text specified as an attribute in the structure
  • From XMP – Uses data stored in the file as XMP metadata in one of 3 locations that you specify: Title, Description, or Headline
  • From Other XMP – Uses data stored in some other XMP metadata field which you specify with the namespace and property name.

 EPUB and HTML Options

Used for EPUB and HTML conversion settings and does not apply to PDFs.

Sep 012012

If you haven’t already discovered it, Adobe has added enhanced tagging of PDF exports from InDesign files. InDesign now tags lists for the first time and more completely tags tables than in previous versions.

For me, list tagging is a big deal since I deal with technical research documents that frequently contain a large number of lists. In exports of tagged PDFs from previous versions of InDesign I always had to search out and manually tag lists in the tag tree of exported PDFs. In version 5.5, if I use the Bullets and Numbering formatting function to create paragraph style tags to format unordered and ordered lists, the resulting PDF has correctly tagged lists. This results in substantially less time spent in the overall process since it is a lot faster to use paragraph style tags created using the Bullets and Numbering function than it is to manually update a tag tree in a PDF for every instance of a list.

The Bullets and Numbering dialog is shown below. It is accessed from one of several locations including the Paragraph Style palette and the Paragraph palette. Use this dialog to format all lists that you want properly tagged when exported to a tagged PDF.

The other tagging enhancement added with this version of InDesign is to tables. Previous versions of InDesign partially tagged tables if you used the Table function to build your tables. Version 5.5 takes the table tagging further, but still leaves some manual work to be done in Acrobat. The column heads are now properly tagged <TH> denoting a heading rather than as <TD> denoting data. Row heads are not tagged, and still must be manually corrected in the tag tree. The scope of the table cell is not identified for either the column head or row head cells and also must be set. A sample of a simple table is shown below.

Simple table

In order to properly identify the column header row in InDesign, the table should be created using the Insert Table dialog that properly identifies any header rows as shown in the Insert Table dialog below. If you are working with a table created without designated header rows, it can be corrected using Table Options > Table Setup… under the Table menu.

If the header row is designated, the table in the exported PDF will be properly tagged as shown in the tag tree below.

Note the structure of the tag tree. I shows the child tags of <THead> and <TBody> to correctly identify the heading rows and the body rows of the table. Note that the column heads are tagged as <TH>, denoting a heading cell versus the <TD> denoting data cells. The table still requires editing to identify row heads as <TH> rather than <TD> and to properly identify the scope of the heading cells for both column and row heads. The easiest way to complete the tagging in Acrobat Pro is to use the Table Editor which can be found on the Touch Up Reading Order dialog, as shown below.

After selecting the table to be edited, click on the Table Editor button on the Touch Up Reading Order dialog. Then select each of the column heading or row heading cells to be corrected (you can shift click to select multiple column head or row head cells), right click on any selected cell to bring up the option menu, and select “Edit cell properties…” This brings up the Table Cell Properties dialog as shown below.

If it is not already selected, select the Header Cell radio button under Type and then designate either Column or Row for Scope. Note that for spanning column heads, you can also designate the number of columns spanned for Column Span.

For further information on how to use the Table Editor to repair tables in Acrobat Pro review the PDF Techniques for WCAG 2.0 at W3C site relating to the Table Editor http://www.w3.org/WAI/GL/WCAG20-TECHS/pdf.html#PDF20 or review DHHS detailed instructions on editing table tags at http://www.hhs.gov/web/508/tabletags.html.