The screenreader preview is a very useful tool to check your PDF document extensive. You get a visual representation which information of your document is available for a screenreader. In particular you can assess the semantical information of your document.
You will see at a glance:
- is a meaningful document title available?
- is the logical structure of your
- heading hierarchy and paragraphs
- lists and list continues
- tables and table headers correctly implemented?
- are internal links (for example table of contents) available?
- do all external links and email addresses work?
- are alternative texts for figures, formulas available?
- do all form fields have a intelligible quickinfo?
- are there representation errors of special characters?
- do you recognize missing spaces between words?
- are all language assignments correct?
Moreover you have the possibility to execute a text search.
See following chapters to get detailed information how to check the above mentioned issues.
The document title is shown on top in the screenreader preview.
Logical structure of headings and paragraphs
You can recognize headings by the blue font color and the numbers in the symbols of the structure elements. Check the correct hierarchy of your document structure.
Move the cursor on a structure element symbol, then the name of the structure element will be displayed.
Logical structure of lists and list continues
Simple list with bullet points:
The correct structure of a list contains normally a list container ("L"), several list items ("LI"), which contain a label ("Lbl") and the list body ("LBody").
A "LBody" element can contain further block-level elements - in the example below each contains a paragraph.
In multilevel lists a list item can contain on or more additional list containers. This can be recognized through the nested structure.
The nesting begins always with a new list container ("L"), which is within the corresponding "LBody" element.
Logical structure of tables and table headers
Headers assigned via attribute Scope
Just move the cursor on a row or column header (structure element "TH") and then you will get a green highlight in a row or column to check if the scope is correct. Below you see an example where the data cells belonging to column header "Monday" are marked in green color.
Headers assigned via Header IDs
Just move the cursor on a table data cell and then you will get a red highlight on the corresponding header cells which belong to the data cell. Only the next higher level will be marked in red color.
In the same way you can move the cursor on a subordinated header cell to check with the red highlight which are the corresponding headers.
Internal links can be recognized through the two link symbols at the beginning and the end of the linked text.
External links can be recognized through the two link symbols at the beginning and the end of the linked text and they have additionally blue font color with underline.
Just click the link to check its correct function.
Alternative texts are displayed in grey boxes. At the beginning always the name of the structure element is mentioned.
Quickinfo of form fields
The quickinfo is an additional help for users to fill out the form field.
Representation errors of special characters
Sometimes the unicode mapping of single characters is not correct - in the example below the quadratic bullet points could not be mapped correctly.
Check the correct unicode mapping with the tool Edit Unicode Mapping.
Sometimes there is the problem of missing spaces between different words which can be easily identified in the preview.
Use the tool Insert Spaces to fix this issue.
Correct language assignments
Move the cursor in front of a paragraph in another language or in front of a word in another language - the language will be faded in if correctly assigned.
Press the keys STRG+F to activate a text search. The dialog box "Find" will be opened.
Use the search terms "www", "http" and "@" to find external links and to check their function.