“PDF Techniques for WCAG ” is a W3C Working Group Note . When the Link tag has an /Alt entry, screen readers ignore the value of any visible Commonly, front matter is numbered with lowercase Roman numerals. Responsive Web Design with Macaw. L. Roman Contreras. v CONTENTS .. Every tag has a class name. By default that will be auto-generated. 3. If a user. This is a Roman slave collar, one of about 45 surviving examples .. of this tag has moved from the Bargello to the Museo Archeologico tag.
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How can we set up MS Word to work with PDF-eXPLODE? The entire tag must have a standard Windows font applied to it, such as Arial or Times New Roman. If each Tag has to send a selection of contiguous pages (aka. This is without doubt the best-known 'fact' about Ancient Rome, just as Julius of such criticism, the 'mobile field army' tag has stuck, so that it is worth making. This Web page lists PDF Techniques from Techniques for WCAG In this example, the text "WCAG2" (within the LBody tag) has been enclosed in a Span The image below shows the Word document with lowercase Roman numeral .
The value syntax of this attribute is "width:height". The "dynamic-page" tag is an auto breakable page. The "page" tag is an alternative, and represents only a single, no breakable page.
The way of attribute setting is different than in HTML. In order to set a background and border you need to use complex attributes, where first part of attribute name is a complex attribute type, and the second part is the property of this attribute.
Complex attribute parts are separated by a dot ". An another way of setting complex attributes is by using the "complex-attribute" tag. The library is very strict in respecting the corectness of tags and attributes. If an unexisted tag or attribute is detected, the document parser will stop and throw an exception. The id attribute is used to identify tags when using inheritance.
The following code fragment illustrates code that is typical for alternative text for a link. For the hyperlink, verify that the alternate link text is properly coded by one of the following:.
Read the PDF document with a screen reader, listening to hear that the alternate link text is read correctly. Use a tool that exposes the document through the accessibility API and verify that the alternate link text is the text for the link.
The objective of this technique is to help users locate themselves in a document by providing running headers and footers via pagination artifacts. Running headers and footers help make content easier to use and understandable by providing repeated information in a consistent and predictable way. The content of headers and footers will vary widely depending on the document scope and content, the audience, and design decisions.
Some examples of location information that may be used in headers and footers are listed below. Whether the information appears in a header or a footer is often a design decision; page numbers often appear in footers but they may alternatively appear in headers. Consistency helps users with cognitive limitations, screen-reader users and low-vision magnifier users, and users with intellectual disabilities understand content more readily.
The easiest way to provide page headers and footers is in the authoring tool for the document. PDF Techniques for Web Content Accessibility Guidelines Antenna House Authoring tools typically provide features for creating header and footer text and information such as page numbers. In all cases, the tools generate page headers and footers in consistent and predictable layout, format, and text.
In Microsoft Word, use the Insert ribbon, which allows you to specify header, footer, and page number information and layout, as shown in the following images. You can use these tools to specify headers and footers as shown in the following images:. This example is shown in operation in the working example of adding running headers using Word Word file and working example of adding running headers using Word PDF file.
In OpenOffice. When converted to PDF, the page headers and footers appear in the document as they do in the converted Word document in Example 1. This example is shown in operation in the working example of adding running headers using OpenOffice Writer OpenOffice file and working example of adding running headers using OpenOffice Writer PDF file.
In the Add Header and Footer tool, specify text and formats for headers and footers in your document. Use the Previews to make sure the text, fonts, and layout are as you want them for your document. The PDF specification allows running headers and footers to be marked as "pagination artifacts" as defined in section If section headers are used in the running header or footer, check that the section header and the running header or footer are consistent.
The objective of this technique is to provide a mechanism that allows users to explicitly request a change of context using the submit-form action in a PDF form.
The intended use of a submit button is to generate an HTTP request that submits data entered in a form, so it is an appropriate control to use for causing a change of context. Examples 1 and 2 demonstrate how to add a submit button using specific authoring tools.
There are other PDF tools that perform similar functions. Access the context menu for the button and select Properties In the Options tab, choose an option in the Layout menu for the button label, icon image, or both. For Select Trigger, choose Mouse Up. The Mouse Up event is keyboard accessible and, in addition, ensures that the button will not change context unexpectedly, as it might with, e.
For each page that submits a form, visually verify that the form contains a submit button and check one of the following:. Tab to the button and check that it submits the form in response to user action to select the button.
Open the PDF document with a tool that is capable of showing the submit-form action and check that the button action is to submit the form.
Both assistive technologies and conventional user agents can render text more accurately when the language of the document is identified. Screen readers can load the correct pronunciation rules. Visual browsers can display characters and scripts correctly. Media players can show captions correctly. As a result, users with disabilities are better able to understand the content. In the "Reading Options" field, select the default language from the "Language" combo box.
Acrobat includes 16 preset language selections. If you need to specify a language that is not on the list, such as Russian, you must type the ISO code for the language, not its name. Documents authored in Microsoft Word: Setting the language for an entire document in the Document Properties dialog box [see Example 1] corrects all errors related to this option.
ISO Codes. Verify that the default language for the document is correctly specified by applying one of the following:. Read the PDF document with a screen reader, listening to hear that the text is read in the correct natural language.
Use a tool that exposes the document through the accessibility API and verify that the language is set to the default language. The objective of this technique is to help users locate themselves in a document by ensuring that the page numbering displayed in the PDF viewer page controls has the same page numbering as the document. Many documents use specific page number formats within a document.
Commonly, front matter is numbered with lowercase Roman numerals. The main content, starting on the page numbered 1, may actually be the fifth or sixth page in the document. Authors should make sure that the page numbering of their converted documents is reflected in any page number displays in their user agent. Consistency in presenting the document's page numbers will help make navigating the document more predictable and understandable.
This toolbar displays the page number in a text box, which users can change to move to another page. In addition, users can select the arrows to move one page up or down in the document.
The toolbar also displays the relative page number location. In the image below, the default display indicates the user is on page 1 of 4 pages. This brings up a dialog box to go to a specific page number. The example document converted from Microsoft Word has 4 pages, numbered i, ii, iii, 1. The image below shows the Word document with lowercase Roman numeral page numbering specified In Word using:.
In this document, a new section has been created with page numbering beginning with Arabic numeral 1 on the fourth page of the document. The document was then converted to PDF from Word. The following image shows the page thumbnails in the Pages panel and the Page Navigation toolbar. In the Page Numbering dialog, select the lowercase Roman numeral style and the starting page 1 by default, which is correct in this case.
The following image shows the correct page numbers for the 4 pages. Note that page iii is selected in the Pages panel and the Page Navigation toolbar shows iii in the text area.
In addition, the relative location in the document is shown at the right of the toolbar: This example is shown in operation in the working example of specifying page numbers in a document converted from Word Word file and working example of specifying page numbers in a document converted from Word PDF file.
The following code fragment illustrates code that is typical for specifying multiple page numbering schemes in a document. This numbering scheme requires 3 page-label dictionaries for lowercase Roman, Arabic, and prefixed numbers.
For every section in the document that uses a different pagination format, check that the page navigation feature uses the same format used on the document pages:. Select the pages that begin a new pagination format and visually verify that the same format and page number is shown in the page navigation feature.
Using a screen reader, check that the page number announced in the page navigation feature is the same as the page number announced on the document page. Document titles identify the current location without requiring users to read or interpret page content. User agents make the title of the page easily available to the user for identifying the page. For instance, a user agent may display the page title in the window title bar or as the name of the tab containing the page. Select the Description tab to view the metadata in the document, including the document information dictionary.
Note that, with Adobe Acrobat installed, you can also enter and read the data properties information from the desktop. Access the file's context menu, choose Properties, and select the PDF tab.
Any information you type or edit in this dialog box also appears in the Document Properties Description when you open the file. This example is shown in operation in the working example of displaying document title in the title bar. Verify that the title for the document is correctly specified and displayed in the user agent title bar by applying one of the following:. Open the PDF document with a screen reader, listening to hear that the document title is read correctly.
Using a PDF editor, check that the document title is specified. Select the Initial View tab to check that the title will be displayed. Both assistive technologies and conventional user agents can render text more accurately when the language is identified. This technique can be used to set the default language for the entire document if the entire document is contained in the container or tag.
In this case, this technique would apply to Success Criterion 3. Select the Tags tab in the Show Order Panel and select the paragraph that is in the different language. You can also use the Options menu in the Tags tab: In the Tags tab in the Properties dialog, select the language from the drop-down list. Select the word or phrase that is in a different language and create a tag for it in the Reading Order Panel e. Open the Tags tab in the Show Order Panel and select the tagged word or phrase that is in the different language.
When you tag a word or phrase, Acrobat splits the original content into three document content tags: As needed, drag the document content tag for the selected text into position between the other two tags, so that the text reads in the proper order. All three tags must also be at the same level beneath their parent tag. Drag them into place if they are not. This example is shown in operation in the working example of marking a specific word or phrase in Acrobat Pro.
Below the level of the default document language, the language for a passage may be specified for the following items:. Read the PDF document with a screen reader that supports the language of the phrase and the language of the surrounding text, listening to hear that the text is read in the correct natural language.
Using a PDF editor, select the word or phrase that is in the different language and check that the language is set correctly. Use a tool that exposes the document through the accessibility API and verify that the language for the passage or phrase is set correctly.
Verify that if the container or tag contains the entire document, the language setting is the language intended as the default for the document. The purpose of this technique is to show how table cells in PDF documents can be marked up so that the logical relationships among rows and columns are preserved and recognized by assistive technology.
However, tables converted to PDF may have incorrectly merged or split table cells, even if they were marked up correctly in the authoring tool. This example uses a table that was marked up correctly when it was created in Microsoft Word.
Some table headers span two rows in the header row; one table header spans two columns. Select the table by clicking the number in the top left hand corner of the table 3 in the reading order in the image below. The red outlines may not exactly match up to the table cells but you should be able to determine if the cells are tagged correctly. The following image shows the example table in the TouchUp Reading Order tool. Note that the Results header appears to span two sub-headers and the other headers to the left span the two rows in the Results header.
The following images shows the example table in the Table Editor. The cells are outlined in red, and the tab for each cell is displayed. Upon conversion, the Results header was incorrectly split and does not span its two sub-headers.
The headers to the right were incorrectly split into 2 cells each and do not span the Results headers. In addition, the incorrectly split cells were merged into one cell.
Press OK. You'll get a warning that the change might result in a malformed table structure. In this case, the change is correct. The cell you changed should change color to show the new span, as shown in the following image.
The following image shows the correction being made to the last header cell, with the corrected header cells to its left. This example is shown in operation in the working example of repairing table structure Word file and working example of repairing table structure PDF file. Configure the screen reader to not use heuristics to read table header cells.
The intent of this technique is to create lists of related items using list elements appropriate for their purposes. When markup is used that visually formats items as a list but does not indicate the list relationship, users may have difficulty navigating the information.
An example of such visual formatting is simply using line-breaks to separate list items. Some assistive technologies allow users to navigate from list to list or item to item. If the lists are not correctly formatted with list tags, these users will have difficulty understanding the list content. The easiest way to create lists in PDF content is to format them properly using list markup in the authoring tool, for example, Microsoft Word or OpenOffice.
However, if you do not have access to the source file and authoring tool, you can use Acrobat Pro's TouchUp Reading Order tool and the Tags panel. Lbl - the list item label.
Contains distinguishing information such as a item number or bullet character. LBody - the list item body. Contains list item content, or in the case of a nested list, it may contain additional List tag trees.
On the Home ribbon, use the lists tools to create or repair lists in Word documents. This is the easiest way to ensure that lists are formatted correctly when they are converted to PDF. In the image below, the numbered and bullet lists were created using the list tools.
The third list did not use the list tool see the ribbon and the list will not be tagged as list elements when converted to PDF. Use the Bullets and Numbering tool to create or repair lists in OpenOffice. The third list did not use the list tool see the toolbar and the list will not be tagged as list elements when converted to PDF. This example is shown in operation in the working example of adding lists to OpenOffice Writer documents.
Inspect the lists in the document to determine which, if any, are not formatted properly. In the following image, the third list is formatted as text. The list items are separated only by line-breaks.
Assistive technology may not be able to render the list intelligibly for users. This example is shown in operation in the working example of ensuring lists are properly formatted in Acrobat Pro.
The following code fragment illustrates code that is typical marking up a list hierarchy in PDF documents. It uses the simple numbered list in the previous examples.
Read the PDF document with a screen reader, listening to hear that list is read correctly when reading the content line-by-line. Use a tool that is capable of showing lists to open the PDF document and view the list to check that it is correctly structured. Inspect the tag tree to verify that the list is structured according to the PDF specification.
Use a tool that exposes the document through the accessibility API and verify that the list is correctly structured. The objective of this technique is to notify the user when user input to a field that requires a specific, required format e. If the required format is not used, an alert dialog describes the nature of the error in text.
User agents, such as Adobe LiveCycle can provide automatic alerts as described in the examples below. Once the user dismisses the alert dialog, it may be helpful if the script positions the keyboard focus on the field where the error occurred, although some users may expect the focus to remain on the last control focused prior to the alert appearing.
For example, if the alert announces an error in a phone number format, positioning the focus on the phone number field when the alert is dismissed can be regarded as helpful and expected.
If multiple input errors occur on the page, an alternative approach to error notification should be implemented. Ensuring that users are aware an error has occurred, can determine what is wrong, and can correct it are key to software usability and accessibility.
Meeting this objective helps ensure that all users can complete for-based transactions with ease and confidence. Many fields -- telephone number, postal code, date -- must have data entered in a specific format or pattern. In the Format tab, select the Format Category in this case, Date. The Date Options appear. When a user types a recognized date format, it is converted automatically to the specified format.
If the date format or value is not recognized, an error alert appears and provides further information, as shown in the image below.
This example is shown in operation in the working example of Required Fields in Acrobat. Because this is a date field the Patterns-Date Field dialog appears. Select the pattern or format you want users to enter. Then click OK. In the Object palette, use the Validation Pattern Message box to type a warning message.
For each form field that requires specific input, verify that validation information and instructions are provided by applying the following:. Check that the format or value that is required is indicated in the form control's label. Use an erroneous format or value and move off the field: The objective of this technique is to ensure that interactive form controls in PDF documents allow keyboard operation. Form controls are implemented in PDF documents either as described in Section Form controls allow users to interact with a PDF document by filling in information or indicating choices, which can then be submitted for processing.
Users who rely on keyboard access must be able to recognize and understand the form fields, make selections, and provide input to complete the forms, and submit the form, just as sighted users can. Interactive form controls can be provided for forms created by converting a scanned paper form to tagged PDF or by creating a form in an authoring application such as Microsoft Word or Open Office and converting it to tagged PDF.
However, documents created by authoring applications that provide form design features might not fully retain their fillable form fields on conversion to PDF. Complex forms in particular may not have properly converted form fields and labels when tagged in conversion. Using Adobe Acrobat Pro with forms in converted documents, you can ensure that form fields are keyboard accessible and usable by:. If you have a form in a tagged PDF document created by scanning a paper form or using an authoring tool to generate tagged PDF , you can use Adobe Acrobat Pro to make the form elements keyboard accessible in the same page locations as the static form.
The following image shows the resulting form fields after the Run Form Recognition tool is run. This example is shown in operation in the working example of Interactive Controls in Acrobat. Open the Add New Field menu on the upper left, and select a form field to add. The image below shows the menu of fields. This example is shown in operation in the working example of Interactive Controls in LiveCycle Designer.
To edit fields, select the context menu for the field and select Properties The properties menu for that form field lets you modify it, as shown in the following image. The tooltip is not keyboard accessible but will be screen-reader accessible: Providing name, role, value information for form fields in PDF documents.
You can use Adobe LiveCycle Designer to create new forms. In addition to invoking this standalone tool from the Windows Start menu, you can invoke it in Adobe Acrobat Pro:. The New Form Assistant creates a blank form. Use the Object Library in the right pane to select form controls. You can also use LiveCycle Designer to create forms based on commonly used forms templates. Invoke the Template Assistant wizard from the New pulldown: Select Forms and then select an appropriate type of form.
Then, you can personalize the form by swapping out placeholder text, graphics, form fields, and properties with custom objects that you provide or define. The following code fragment illustrates code that is typical for a simple text field such as shown in Examples 1 and 2. For each form control, verify that it is properly implemented by tabbing to each form control and checking that it can be activated or that its value can be changed from the keyboard.
The entire document is also available as a single HTML file. W3C liability , trademark and document use rules apply. Techniques for WCAG 2. PDF Technology Notes Introduction The Portable Document Format PDF is a file format for representing documents in a manner independent of the application software, hardware, and operating system used to create them, as well as of the output device on which they are to be displayed or printed. It is intended for use by tools that perform the following types of operations: Simple extraction of text and graphics for pasting into other applications.
Processing text for such purposes as searching, indexing, and spell-checking. Making content accessible to people who rely on assistive technology.
PDF File Production and Accessibility PDF files may be produced either directly by application programs or indirectly by conversion from other file formats or imaging models. There are two principal indirect methods: Microsoft Office 10 - a suite of desktop office applications that creates tagged PDF. API Inspection Tools aDesigner - a disability simulator from the Eclipse Foundation that helps designers ensure that content is accessible and usable by visually impaired users.
Accessibility applications such as screen readers can interface with Acrobat or Adobe Reader in two ways: Recent versions of Acrobat and Reader have enhanced the support for accessibility interfaces: On the TouchUp Properties dialog, select the Tag tab. On the Tag panel, type the text alternative in the Alternate Text text box. Right-click on the image and choose Edit Alternate Text.
The Alternate Text dialog will be displayed. Type the text alternative in the Alternate Text text box. Access the context menu for the image and choose Picture Resources are for information purposes only, no endorsement implied.
Providing short text alternative for non-text content that serves the same purpose and presents the same information as the non-text content. Using a PDF editor, check that a text alternative is displayed for each image. Expected Results Check 1 is true for each image in the document which needs a text equivalent. Create a table of contents at the beginning of the Word document.
Create a table of contents at the beginning of the OpenOffice.
The image below shows the Bookmarks options menu. The next image shows the selection of links in the document for bookmarking. Providing a Table of Contents. Procedure Check that the Bookmarks panel displays bookmarks. Check that the bookmarks link to the correct sections in the document. Expected Results Check 1 and Check 2 are true. Common tab-order errors include: Form fields missing from the tagged content.
If needed, select a tab order option: Option Description Use Row Order Tabs from the upper left field, moving first left to right and then down, one table row at a time.
Use Column Order Tabs from the upper left field, moving first from top to bottom and then across from left to right, one table column at a time. Use Document Structure For tagged documents, moves in the tag order specified by the authoring application. To correct the reading order in Example 5, use the Tags panel, and either Drag-and-drop the H1 tag to precede the required-field text tagged H2 , or Cut-and-paste the H2 tag to follow the H1 tag.