Please note, the Accessibility Toolkit was last updated in 2014. Recommendations included in the Toolkit may not reflect current standards or best practices.

Audio-visual materials


Audio-visual materials can include videos, audio files (podcasts, MP3s), training material such as guided tutorials and webinars, among others. The biggest accessibility challenge of this format is that the information that is conveyed through this medium is fully reliant on either audio or vision to convey the message. A person who has a visual impairment will not be able to absorb information conveyed through an image, just as a person who has a hearing impairment will not be able to access information conveyed through sound. This section offers the Toolkit users a better understanding with regard to institutional obligations for making audio-visual materials accessible under the Accessibility for Ontarians with Disabilities Act, 2005 (AODA), highlighting best practices to help ensure that your library is able to meet these requirements.

What are the AODA requirements regarding audio-visualmaterials?

While the standards for accessibility of audio-visual materials outlined in the AODA’s Integrated Accessibility Standards Regulation (IASR) can be interpreted in different ways, there are two accessible formats that the legislation explicitly requires: captioning and descriptive audio.

Material in e-reserves and learning management sites falls under the “intranet” definition in the IASR because it is usually secured behind authentication. If the audio-visual material is not intended for general public use (as on a public website), it qualifies as training material (see IASR, Section 15 for details), and as such an accessible version can be provided upon request.

If the material is available publicly online, it falls under Section 14 of the IASR, and institutions are obliged to provide this material in an accessible format, regardless of whether or not there is an explicit request for it.


Including captions in video and multimedia communications increases accessibility for all users, especially users with varying hearing disabilities. There are two main types of captioning options: “closed” captions allow viewers the ability to turn the captions on or off, while “open” captions remain fixed to the video and are visible at all times. There is a commonly held belief that closed captions are preferable because having open captions can overwhelm some viewers (and could have an especially negative impact on those with cognitive processing challenges).

Subtitles vs. captions

Subtitles typically only transcribe into text the verbal/spoken portions of a video, while captions convey the significant sounds from a video as well. With captions the non-verbalinformation is usually displayed in square brackets, for instance, [sound of sirens and car horns], [instrumental music], [background music fades out].

The Web Captioning Overview from Web Accessibility in Mind (WebAIM) explains more information about captions (open and closed), audio descriptions and transcripts, as well as offers a list of terms of technologies related.

The Described and Captioned Media Program (DCMP) Caption it Yourself website offers instructions and guidelines for in-house captioning, as well as a list of web-based captioning tools, downloadable software, and caption-ready video hosting providers.

Online audio-visual files

Streaming media requires an online player that can turn captioning on or off. This requires atext-based file with an integrated timecode that the player understands and syncs with the video. There are several different formats for these captioning files.

  • .SRT: Captions for YouTube, older JW FLV Player or for DVD subtitles longer than 32 characters per line
  • .VTT: WebVTT format for HTML5 video
  • .DFXP.XML: DFXP timed text for Flash with begin/end tags.
  • .QT.XML: QuickTime TeXML subtitles. These are like QT.TXT but have a more modern UTF-8 character set support.


A transcript is a text-version of a video, which includes a meaningful description of all narration, dialogue, and sound effects. When captioning options are not available, attaching an accessible text based transcript document to the video might be possible.

For more information on best practices for creating web-based audio transcripts, visit Transcripts on the Web: Getting People to Your Podcasts & Videos, produced by uiAccess.

Audio description

The Canadian Radio-television and Telecommunications Commission (CRTC) defines Audio Description as:

“…a narrated description of a program's main visual elements, such as settings, costumes, or body language. The description is added during pauses in dialogue, and enables people to form a mental picture of the program.”

This definition and other useful information can be found in the CRTC’s guide to TV access for people with visual impairments. This guide explains why audio description and described videos are important and offers links to related projects and services.

Additional resources

What makes audio-visual materials accessible?

Physical media may have captioning included with it. This requires a video player be available that will display the captioning. Described video (known to some as descriptive audio) is provided on request.

Audio-visual media are considered adequately accessible when:

  • there are captions that can be displayed or activated easily by viewers (for publicly accessible online videos or audio files as per IASR, Section 14)
  • when a video includes a Described Video option (not necessary for audio-only files)

For compliance with Sections 15, 12 and 18 of the IASR, an audio track must be added to a video to convert it to a Described Video format when “notification of need is given.”

What kind of procurement decisions need to be made when purchasing audio-visual formats?

Currently libraries are only obliged to provide these upon request, but you should consider purchasing all media, as available, with existing captioning and descriptive audio. Having these formats readily available will enable libraries to meet accommodation requests in a more efficient and timely manner.

Physical media (for example, DVDs in your circulating collections) should have the capability to at least enable captioning to appear or have it embedded. It would also be beneficial if this material came with descriptive audio or at least a transcript.

Streaming media should come with a captioning file, descriptive audio or at minimum a transcript.

Descriptive audio is an interesting case as it can change depending on the educational purpose of the video. For example, for a film studies course, descriptive audio for the movieKing Kong could be very different than for a women’s studies course. The context of the use of the video will best determine how to create the descriptive audio.

Procurement of services to make audio-visual materials accessible

It might not always be possible for libraries to acquire captioned audio-visual formats. In these cases, external services may be required in order to provide accessible formats upon request.


The following considerations should be kept in mind:


  • the service should create a caption file(s) for streaming
  • jargon specific to a given field may not be correctly recorded by a service
  • the turnaround time pertaining to captioning could be problematic with lecture capture or other uses which require the media to be available quickly

Descriptive audio

  • Who creates this? Is it sent to a service that your library regularly uses?
  • What are the costs and who is responsible for these costs?


The following technologies can help with in-house video captioning:

Open source

Paid software

Procurement of accessible audio-visual materials

Negotiating with vendors to provide accessible formats for all audio-visuals will save library staff a lot of time when accommodating user requests for accessible formats. Libraries should consider making every attempt to purchase media that is already captioned. If it cannot be purchased, the media might be captioned by a third party before it is made available to users.

How can I caption videos legally? Considerations when securing legal permissions

Permission should be sought to provide closed captions for videos. For a sample draft of a permission form to secure the copyright or rights holder’s permission to provide closed captioning, refer to the Negotiating for accessible audio-visual formats section of this toolkit.

Getting a video or an audio file captioned, or captioning it yourself often means duplicating the video (creating a second online or physical copy with captions.) As per Section 32 of the Canadian Copyright Act, you can convert almost anything into an accessible format except for “cinematographic works,” and those are defined as: “any work expressed by any process analogous to cinematography, whether or not accompanied by a soundtrack.”

Whereas most videos from larger production companies will include captions or at the very least subtitles, videos by smaller organizations may not have captions. In those cases, you can contact the copyright holder (usually the producing organization) and ask them about getting the file captioned. In some cases online/freely available videos will not include captions but the commercially-available DVD version will, so it is best to inquire.

For uncaptioned videos posted online on services such as YouTube or Vimeo, you generally are not legally permitted to extract and re-post the video with captions. Using the “automatic captions” available on YouTube is not recommended due to the poor quality. If the video is posted with a Standard YouTube License (which most are) you cannot legally extract and repost it with captions (even if your motivations are merely to make it more accessible). If it has a Creative Commons license you may be able to, but you have to look at the terms of that License.

Another option is to try using Overstream or Amara (linked above) to caption a video yourself (which doesn't technically reproduce the video) but you need to be certain to give viewers the appropriate link to the video that takes them through the “captioned overlay.”

For more information on other legal considerations, please refer to the Law and administration section of this toolkit.