Joe Clark: Media access

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Accessibility implications of digital rights management

Posted 2003.04.07 ¶ Updated 2003.04.09

Accessibility implications of digital rights management


“Digital rights management” refers to hardware and software that attempts to control access to and reproduction of digital information. DRM masquerades as a method of protecting authors’ copyrights but, in practice and according to published proposals, actually limits the copyright freedoms of the general public, a group that includes people with disabilities and others who rely on accessibility features like captioning, audio description, subtitling, and dubbing.

DRM has a number of implications for viewers who require accessibility features. Almost all the implications point to a reduction in usefulness, convenience, and engagement of existing legal rights.

Table of contents (skip)


If you’re new to accessibility, you may wish to read my full glossary, but here are a few basic terms to get us started.

Accommodating characteristics a person cannot change or cannot change easily, such as disability or language.
Transcription of dialogue, notation of sound effects, and identification of speakers. Visible words. Meant for deaf and hard-of-hearing viewers.
Translation of dialogue (and a few unusual other items, like onscreen type). Visible words. Meant for hearing, sighted people who don’t understand the source language.
Audio description
Added narration track that explains whatever is happening onscreen that could not be understood from dialogue alone. Audible words; description talks you through a program. Meant for blind and visually-impaired viewers.
Translation track that replaces audio in the original language. Audible words. Meant for hearing people who don’t understand the source language.
Refers to an accessibility feature that is permanent, and can’t be turned off.
Refers to an accessibility feature that is optional and can be turned off or on.
Digital rights management (DRM)
The only definition I could find that doesn’t use protect as every third word in every sentence is: “Various schemes to enable protection of copyrighted material at the server, client or both for the purpose of restricting distribution on behalf of copyright holders.” (Emphasis added.)
For the purposes of this paper, programming refers to any cinema, television, or other audiovisual artwork irrespective of its medium of transmission. A TV show, an online video movie, and a home video are all “programming” here.




Not all of DRM’s implications for accessibility are important or will significantly inhibit or inconvenience the user. This paper attempts to document every known example without implying that all are equally – or even similarly – significant.

General procedural implications

For all accessibility “tracks” (captions or subtitles, or dubbing or audio-description recordings), DRM may prevent you from doing the following:

Even when not reiterated in the categories below, the above limitations will probably still be in effect.


  1. You may not be able to electronically monitor closed captions as they are transmitted. TV-tuner cards in computers do that now.
  2. You may not be able to capture or record caption text. Some tuner cards, and commercial data-recovery decoders, capture caption data into computer files. (It’s theoretically possible that data-recovery decoders may be exempted from DRM given that they are “professional” devices; “professionals” will be assumed not to be the thieves consumers are.)
  3. If you cannot capture captions, you cannot post them online for fans’ reference.
  4. More seriously, if you cannot capture captions, it becomes impossible to recaption a program later on if:
    • you’re a caption service provider
    • you’re given a program to caption (e.g., for conversion to PAL or NTSC television format, or for syndication, where the program runtime and commercial breaks are different)
    • you cannot locate the original captioner, or the original captioner cannot find its caption files, both of which happen today
    You end up recaptioning from scratch.
  5. You cannot extract the captions and use an offscreen display (if you’re visually-impaired, for example).
  6. You cannot use a software decoder that you build yourself from the publicly-available specifications, unless it is pre-authorized and includes compliant DRM.
  7. In fact, conceivably every step along the captioning production path (uncaptioned program; digitization into captioning software, transcription, editing, timing, and positioning; proofing; encoding and transcoding; delivery) could require compatible DRM. Such a requirement would be orders of magnitude worse than a hardware equivalent one could imagine – a dongle that must be attached to every computer that uses a certain software program – because of the wide range of devices that manipulate the data during captioning (tape decks, satellite or Internet delivery systems, captioning software, encoding software and hardware).
  8. You cannot add further caption streams to an already-captioned program. This actually happens: Either a show gets translated into a second language or it receives children’s easy-reader captions. Because the existing caption stream is locked into the digital signal by DRM, you cannot extract the first stream, create additional streams, and re-encode all streams back into the program. (That workflow represents what you have to do today with closed captioning. Digital technologies may permit addition of new tracks without touching the old ones, but that won’t be true if DRM prevents it.)
  9. Similarly, you cannot create captions for different aspect ratios if you already have a caption file for a certain aspect ratio. (For example, if a movie comes up for broadcast and the only file you can find is for a widescreen version, you have to recaption from scratch for a fullscreen version. Or if an initial home-video release were in fullscreen, with widescreen added later in a director’s-cut rerelease, the initial captions could not be tweaked to fit the new dimensions.)

Many of these practices could continue without significant obstacle by converting DRM-labeled digital works to analogue, if possible, and working on them in that form. The analogue hole is a large Achilles’ heel in digital rights management. However, in today’s analogue captioning, it is already easy to find producers who didn’t want their tape taken down another generation to encode captions. Digital tape formats have eliminated that concern, but if the only way to add accessibility is to convert from digital to analogue and back again, those same objections are going to resurface.


  1. Fansubbing disappears. When fans of animé find a program that hasn’t yet been subtitled into English (as an example), they take matters into their own hands and subtitle the program themselves. It’s illegal in most cases and dubiously legal in others, but that doesn’t actually matter, because the copyright holder benefits. (It is within a copyright holder’s authority to deny reproduction rights to the world; a work can be hoarded until the expiration of copyright. But would that be in the interests of Japanese animation firms? Hardly.) Studios tend not to bother suing if the fansubbed animé is not sold at a price. And in fact, there’s a submarket of distributing subtitle files that the home viewer syncs up with his or her video signal.
  2. Closed subtitling, while technically present, effectively becomes hardsubbing (open subtitling). Today, if you’ve got a video stream with closed subtitles (either using TV closed captions or DVD subpictures, for example), you can rip the video without the closed subtitle stream and resubtitle the video as you wish. (Or add other accessibility features. Or simply remove the subtitles because that’s what you want to do.) DRM-locked video may make subtitles inseparable from the original source. You might still be able to add other titles or audio tracks, but the ultimate viewer could activate the original closed subtitles, causing overlapping subtitles or dubbing or audio-description tracks that don’t conform to what’s on the screen. (This again is not a world-shattering problem, given that closed-captioned foreign-language productions simply reuse the subtitling script rather than captioning the dubbing track, so a mismatch between audio and captioning is seen today already.)
  3. Similarly, you might simply be unable to turn the subtitles off. Even today, the DVD specification allows authors to force subtitle tracks to appear.
  4. It may be impossible to add captions to a subtitled video (or add descriptions or a new dubbing track). It always shocks the hell out of subtitling purists, but subtitling is not sufficient for deaf people because a lot of dialogue is left out, as are non-speech information (sound effects, manner of speech) and even singing. Subtitles also do not move to indicate who’s speaking, which is necessary in pop-up captions. To make a subtitled program accessible, you have to add captions, an action that DRM-locked programming may prevent.


  1. You may not be able to redub the program to accommodate regional accents. For example, you may be a French or Swiss broadcaster presented with a Quebec-dubbed film. Even though the differences in quality between Canadian and continental French are vastly overblown, you may wish to transcribe the French dialogue (or you may have access to the script) and redub the program in approved accents.

Audio description

  1. You may not be able to record the program with always-audible descriptions. It’s already difficult to do so on some analogue VCRs because they cannot record the Second Audio Program (SAP) soundtrack where descriptions usually are broadcast. A DRM-locked recording device may heed the digital rights allocated in the original, which state that only main picture and main audio may be recorded. The issue here is not that a rightsholder might ban recording of audio descriptions, rather that the rightsholder might not even know about description in order to specifically enable it. In DRM, everything that is not permitted is prohibited; innocent mistakes like these (though they speak of incompetence) will have unintended consequences. (We already see a similar phenomenon: A movie may be described for first theatrical run, but not show up on DVD with the description track. Usually the home-video division does not even know the track is available.)

Set-top boxes

Digital set-top boxes are an overlooked issue in accessibility. Blind people can’t use visual menu systems, and people with mobility impairments cannot necessarily use a remote control to operate those menus. (The same holds true for visual menu systems on home electronics, like TV sets, VCRs, and DVD players, but let’s simplify this discussion to STBs.)

You can design a menu system for STBs that includes accessibility upfront, but nobody has done that yet or is likely to without substantial lobbying efforts. However, I have worked on a project that attempts to graft accessibility post facto onto a digital set-top box. A DRM-locked STB might:

Online implications

  1. Any accessibility feature in a language and format that rightsholders consider commercially attractive could be banned online. As an example, an online closed-caption file might be banned because people would attempt to extract the captions and post those as a kind of spoiler.
  2. Or instead of refusing to post the program with accessibility, the rightsholder might specify that the access feature be open, as with open captioning, and in a form that is uncapturable unless you pause the video with each caption and take a screenshot.
  3. But, in a further Catch-22, open captioning could be prevented because the captions could be run through optical-character-recognition software and republished.

In some nations (e.g., the U.S. and Canada), it is explicitly legal to adapt a copyrighted work into a form understandable to a blind person or a person with another perceptual disability. Generally, “cinematographic works” are excluded, as is large print. Some legislation specifically mentions Braille and analogue and digital audio as formats into which it is permitted to adapt copyrighted works.

But some legislation (notably Canada’s) makes it legal to adapt sound recordings for disabled persons. Sound recordings could be subject to DRM. It is already possible to convert a sound file into a video format with no picture but with captions or subtitles. Such an adaptation could be permitted under copyright legislation if the ultimate format were one restricted to people with disabilities. At present, I don’t know of any format that qualifies, but some later version of the DAISY electronic talking-book format might.

Conclusions and recommendations

  1. Digital rights management, as currently designed, will harm people with disabilities and others who rely on accessibility features.
  2. DRM must needs to specifically enable at least the same level of customer use of, reuse of, and tinkering with accessibility features that are enjoyed today.
  3. DRM must be exempted for the process of producing captioning, audio description, subtitling, and dubbing, whether those producers are deemed “professional” or “amateur” by DRM licensors or anyone else.
  4. DRM must not prevent legitimate, legal adaptations of copyrighted works for people with disabilities.

See also