This document summarizes information gathered by a research team at Penn State. The team investigated various services and techniques related to audio description for the vision impaired.

Table of Contents

Research Team

  • Jennifer Babb, Assistant Learning Designer, Dutton Institute, College of Earth and Mineral Sciences
  • Patrick Besong, Multimedia Specialist, Teaching and Learning with Technology
  • Michael Brooks, Manager of Multimedia & User Experience Team, World Campus
  • Teri Dreibelbis, Instructional Design Assistant, Liberal Arts Outreach
  • Elizabeth J. Pyatt, Instructional Designer, Teaching and Learning with Technology
  • With input from Michelle McManus, JooYoung Seo, Deniz Döke, and Donald Tusler from Teaching and Learning with Technology

What is Audio Description?

Audio description (AD) for individuals with visual disabilities refers to the insertion of audio content describing “important visual details that cannot be understood from the main

soundtrack alone” (United Access Board ICT Standards and Guidelines, §E104.4). Information in an audio description should be provided in a way that does not interfere with other audio such as dialogue or sound effects.

Audio description allows a person with impaired vision to fully understand the visual content delivered via video or live performance. In recent history, AD has been offered for a variety of commercial movies, television shows, and theatrical venues, but is less common in educational videos. This paper will focus on using AD for recorded video in the educational setting, where the understanding of content is essential to achieving learning objectives.

Watch this short (1:04 minutes) video with and without audio description as a person without vision would see it.

Note: Video has no visuals.

Video Players: DVD vs. Online

It is important to think about how the video with AD is presented to students. An issue for higher education is that a course video is often provided in an online player instead of a DVD. While it is ideal to offer one video with two tracks that students can self-select, similar to how most DVD players work, the reality is that many online video players do not provide that functionality at all or not in a way that is easily accessible to a large audience. Given that fact, it will most often be necessary to provide two different videos: one with AD and one without. The downside to this is that it creates a separate experience for users who need the audio descriptions and it duplicates the video assets, increasing the content that needs to be managed.

Techniques for Audio Description

There are various ways to provide audio description. The option you choose depends on student needs, available resources, and the stage of the project.

Hiring a Vendor

The traditional solution is to hire a vendor to create an audio description track after the video has been completed. Several vendors are listed in the resources section of this paper.

Pros and Cons


  • Expertise: A vendor has the professional expertise to complete the complex process of creating audio descriptions.
  • Results: You should expect to receive high quality results.


  • Cost: Prices vary, but it is generally much more expensive than preparing an AD in-house.
  • Turnaround time: It may take a significant amount of time to get the product back.
  • Subject expertise: Historically, vendor clients have been professional studios that create commercial television and movies, but descriptions for educational video may need to be more in-depth for some aspects of the content.

Creating Audio Description In-House

The team experimented with creating and adding an audio description to a completed video. They discovered that the process can be complex.

The testing revealed two basic options. One is to add the audio description during the natural breaks in dialogue. This is appropriate when there is not a need for lengthy descriptions or if there are long pauses built into the video. The other is to freeze the video, insert the audio description, and then continue with the original video. The second method is best for highly complex videos and scientific experiments without long pauses. See Appendix B: Tips for Creating an Audio Description for additional details.

Pros and Cons


  • Cost: The ability to create in-house audio descriptions can save money over hiring an external vendor.


  • Writing expertise: Significant time is required to write an audio description that ensures accuracy and conciseness and avoids overlapping other important audio cues.
  • Required technical expertise: The description needs to be inserted by a person with video development experience.
  • Required technology: Professional video editing tools may be required.

Using an Embedded Audio Description

Creating an Embedded Described Video allows you to include all relevant visual information in the original video. This is best accomplished with the use of a well-thought-out script that includes references to all relevant visual information. The embedded description can be included either as a voice-over during natural pauses or by the presenter as part of the main dialogue.

Pros and Cons


  • User experience: According to David Errington of Accessible Media, Inc. of Canada (CSUN, 2016), blind viewers actually prefer embedded descriptions because they are sharing the same experience as sighted users yet are getting the information they need. In addition, sighted users can benefit from the description that is included in the video.
  • Savings: It is more cost-effective to do this process up front rather than spending the money to do remediation.


  • Writing expertise: Instructors and video specialists need to learn techniques for creating a script or dialogue that contains all the necessary visual information.
  • Not a universal solution: This might not work for all videos, as it could be distracting in scenes with dramatic action and dialogue or when filming a spontaneous event.
  • Existing videos: This technique does not work if the video has already been produced.

Creating an Annotated Transcript

Another option is to create an annotated transcript that might include other accessible formats such as data tables to represent graphs shown in the video or math equations written in MathML. Descriptions could include time code references to the original video as necessary.

For example, if a video walks students through a math problem, the entire derivation could be replicated in MathML. Similarly, a more in-depth description of complex visual content could be provided as a supplemental description.

Pros and Cons


  • Benefits everyone: These descriptions could benefit sighted students who may want to review the information without any timing issues or distractions from the original video.
  • A deaf-blind benefit: An extended text transcription may be the only way a deaf-blind student could be accommodated.
  • Time and ease: A text description is easier and quicker to create than an audio description track.


  • Different user experience: All students are not receiving the same experience. Students may want to hear original audio (e.g., with speaker intonation) but also need the information in the text. Navigating between a video and text is not ideal.
  • Maintenance: Maintaining two different products requires additional effort to ensure consistency.


The team initially thought there would be a single recommendation for the incorporation of AD but has since realized that the choice will be dependent on content, production status, student need, and financial reality. That said, the one thing we can recommend without hesitation is the importance of planning for accessibility when creating your own videos. One cost-effective method is to incorporate AD into your script before you start filming (Embedded Audio Description, Appendix A).


Basic Information/Guidelines

Sample Videos


Vendors on this list are those whom members of the group spoke with during this investigation.

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