Overview of Audio Description

Audio description is:

• A narration track that verbally describes key visual content that is not accessible via audio alone.
• Also known as "video description", "visual description", "descriptive video", and simply "description".
• An art form, involving an understanding of how much information needs to communicated, what words to use, and when to use them.

Extended audio description is audio description that requires a pause in the video (i.e., if there aren't otherwise enough gaps in the program audio to insert a description.)

Integrated description is the process of building in description of visual content directly into the video during scripting and production, thereby avoiding the need for audio description.

Prioritizing Your Videos for Audio Description

Videos can be prioritized for audio description using the same variables that are used for prioritizing videos for captioning:

• Audience demographics - If the target audience for a video is likely to include individuals who are blind or low vision, the video should be a top priority.
• Traffic - Your most popular videos should probably be a high priority.
• Publication date - Newer videos should probably be a high priority.

In general, it is best to focus initial efforts on high impact videos, for example:

• videos available to the public on a high-use website
• videos that will be used multiple times in a course
• videos developed by several faculty members to be used in several different classes

NOTE: In order to be audio described with the current project, the video must be public-facing.

Does the video need description?

In addition to the above considerations, videos can be prioritized based on the need for audio description.

To determine need, watch portions of the video with your eyes closed. Are there any important details that you're missing? Rate the video using the following scale:

• High need - Nothing makes sense with audio alone.
• Medium need - The video is generally understandable, but critical details are lost.
• Low need - Some information is lost, but it isn't critical.

If videos are hosted on YouTube, consider using YouTube Caption Auditor (YTCA) to help channel owners prioritize their videos. YTCA is a free, open-source tool developed and maintained by Terrill Thompson at the University of Washington. It helps YouTube channel owners to see a table of all their videos, and to sort the videos based on traffic or publication date, which can help with prioritization. It also reports on whether videos have been captioned, but is unable to report on whether videos have been audio described since YouTube doesn't collect this information, and is unable to assess the need for description – you'll have to do that manually.

How to Describe Video (3 Approaches)

Each of the following approaches is described in detail below.

1. Hire a traditional audio description service provider.
2. Hire a captioning vendor, and get audio description as an add-on service.
3. Do it yourself using a timed text file.

Approach #1: Hire a traditional audio description service provider

The ultimate source for audio description service providers is the American Council of the Blind's Audio Description Project, which currently lists approximately 100 providers. Many of these specialize in live events, or only work on major large-budget projects. In 2017, we narrowed the ACB's list to only those providers who expressly offer audio description of recorded video, and surveyed them all regarding their pricing, turnaround time, and deliverables. Based on the survey results, we identified seven providers that seemed to be a good fit for higher education. Since then, some of these providers have merged, and others have entered the market. We will continue to maintain a list of providers with whom we have first-hand experience at Creating Accessible Videos on the UW Accessible Technology website.

For the current project, we partnered with Audio Eyes and Center for Inclusive Design and Innovation (CIDI) at Georgia Tech.

Characteristics of this approach:

• Description is voiced by human narrators, often using professional voiceover talent.
• The output is professionally mixed, so the description is easy to hear and understand against the backdrop of the program audio.
• You generally need to provide them with the original video file; they are typically not able to access videos solely through their URL on video hosting platforms such as YouTube and Vimeo.
• The cost is generally higher than with the other approaches (approximately $10-15/minute depending on complexity, and whether extended description is required).
• Typical deliverable in higher education: An audio-described version of the video.

Choose this approach if:

• Your video is a dramatic work, or is designed to have emotional impact.
• Your video is already captioned.
• You have access to the original video file.
• All other factors are equal, since this approach will yield the best quality result.

Approach #2: Hire a captioning vendor, and get audio description as an add-on service

Vendors in this category are 3PlayMedia and Automatic Sync Technologies. Their primary business is providing captioning of recorded video, but in recent years they have added audio description to their menu of services.

For the current project, we are working with a single vendor, 3PlayMedia, since they are already providing captioning services on a Washington State higher education contract.

Characteristics of this approach:

• Description is voiced using speech synthesis.
• The cost is slightly less than with traditional description providers. 3PlayMedia's current price is $7.50/minute for standard, and $11/minute for extended. There are additional costs for expedited requests.
• Captioning is required, even if the video is already captioned. This is because their audio description process is semi-automated and captions are used programmatically to identify gaps in the spoken audio where description could be inserted. If captioning is needed, combining both services in a single transaction is convenient. However, if it's not needed, it makes the process less efficient and adds to the cost, potentially negating the cost benefit of choosing this approach.
• Typical deliverable in higher education: An audio-described version of the video.

Choose this approach if:

• Your video contains non-dramatic content and is not designed to have emotional impact (i.e., content in which synthesized speech is satisfactory).
• Your video also needs to be captioned.
• Your video is hosted on YouTube or Vimeo, and it's inconvenient (or impossible) to locate and upload the original video file.

Approach #3: Do it yourself using a timed text file.

In this approach, the description text is contained in a time-stamped text file, in Web Video Text Tracks (WebVTT) format. WebVTT files can be used for various purposes, including captions and descriptions. If used for descriptions, they can be voiced by web browsers at the appropriate times.

This approach is part of the HTML5 specification, and enables audio description to be added to video using very simple HTML code, as in the following example:

  <video>
    <source src="somefile.mp4">
    <track kind="captions" src="my-captions.vtt" srclang="English"></track>
    <track kind="descriptions" src="my-descriptions.vtt"></track>
  </video>

Characteristics of this approach:

• It's easy!
• Description can be written from scratch in any text editor. Alternatively, description could be written using any caption editor and entering description text rather than captions, then download a WebVTT file when finished.
• Only one video is needed, unlike both of the previous approaches where the end result is two videos, with and without audio description.
• Extended audio description doesn't require a separate video. The video can automatically pause when description is present.
• This approach currently only works in Able Player, a free, open-source media player developed and maintained by Terrill Thompson at the University of Washington. Able Player is the media player featured on this website.

Choose this approach if:

• You're using Able Player.
• The need for description is relatively simple (e.g., "Medium need" or "Low need" on the scale described above). Describing "High need" videos is best left to the professionals.

Further Reading

• Audio Description of Visual Information - a comprehensive guide from the W3C Web Accessibility Initiative
• Integrated Described Video (IDV) - This website from Accessible Media, Inc. (AMI) includes a series of high-quality videos produced to educate on the benefits of integrated description (i.e., scripting and producing video that avoids the need for audio description)