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ATAG: Authoring Tool Accessibility Guidelines

Online captioning involves more than watching captions; someone must create them. These authors use tools for that job that are subject to their own set of requirements, the Authoring Tool Accessibility Guidelines.


Captions aren’t always made by nondisabled people for the benefit of people with a hearing disability. Some hard-of-hearing people have worked as captioners. Apart from that, it’s quite possible for a person with one disability to work in a field related to another disability. One example is TTY relay operators who are blind. In the case of captioning, people with a physical disability or moderate visual impairment may be perfectly able to do the job – if the authoring tool lets them.

We are dealing with an issue of internal consistency: Tools meant to improve accessibility cannot themselves be inaccessible. Unfortunately, at time of writing none of them has been proved to be accessible.


If we take compliance with ATAG as a reasonable indicator that a program is accessible, it must be stated that no caption-editing program has been subjected to a published evaluation. (This TILE activity did not make any such evaluations, either.)

We do not know that all caption-editing systems fail ATAG, but we don’t know of even one that passes; none have been evaluated. An informed guess would suggest that the majority of caption-editing systems would not meet even Level A compliance, but that needs to be explored via a systematic evaluation.


Because of the likely inaccessibility of authoring tools, some people with disabilities will be excluded from work in the captioning field.

Publishing tools that support captioning

Another problem is the difficulty of publishing your caption files. You can upload them to a server easily enough, but it’s not easy – nor is it easy to make sure that all the additional files needed for accessibility (captions, audio descriptions, longdesc files) are reliably published.

Standards-compliant blogging tools like Movable Type and WordPress make it easy to publish text-and-graphics Web pages that comply with applicable standards, including the Web Content Accessibility Guidelines. This activity proposes that such software be upgraded to make it just as easy to publish video with captions and other accessibility features. The software should make it a foolproof, easy process.

To that end, we’ve written a functional specification for a publishing tool that can be used to upload video files and associated captions and other features. Note that this is a separate issue from the software used to create the captions; we’re talking about getting the finished video online.