What you can do to Make Your Multimedia More Accessible

Captions are one of the most well-known parts of multimedia accessibility, and fortunately, UC San Diego's enterprise media platform makes them easy to add. Every video uploaded to Kaltura automatically receives machine-generated captions using automatic speech recognition (ASR). On average, these captions are about 70-80% accurate.

The good news is that you can improve your captions. Kaltura includes a web-based caption editor that lets you review and correct errors and also allows you to download it and edit it offline. You can even download and edit the transcript version (without timecodes), re-upload the file, and Kaltura's machine alignment feature will automatically synchronize it with the video.

Kaltura also lets you give other users co-editor access to your media, which allows them to help review and edit captions. This can make the process more manageable and distribute the effort among your department or instructional team. (We have a bunch of other recommendations for how to expedite caption editing in case it helps.)

Lastly, one of the simplest ways to improve caption accuracy is to speak clearly and at a natural pace when recording. Avoid rushing through material or talking over others. The clearer the audio, the better Kaltura's machine captions will be.

In accessibility terms, this practice is meant to serve the same purpose as audio descriptions, which are typically narrated explanations of important visual details for people who are blind or have low vision. In our context, though, the goal isn't to create a separate audio track, but rather to teach in a way that makes visuals understandable through narration.

This means being intentionally descriptive as you speak. Here are a few examples of how to make your narration more descriptive and self-contained:

A series of examples of visual information with examples on how to describe them more or less illustratively.

Instead of saying… "Click here, then select this." Try saying… "Click the File menu, then choose Open from the list that appears."

Instead of saying… "As you can see, the blue line goes up." Try saying… "In 1976, the blue line rises sharply while the red line stays flat — that’s where the difference between the two groups begins."

Instead of saying… "Watch what happens next." Try saying… "Next, the solution starts to bubble as the gas is released — that indicates the reaction has started."

Instead of saying… "This one’s bigger, and that one’s smaller." Try saying… "The bar for Group A reaches 50%, while Group B’s bar only reaches about 20%."

Instead of saying… "Let’s move on to the next one." Try saying… "Let’s move to the next slide, which shows the control condition. The data points here form a flat line, compared to the steep upward trend we just saw in the experimental group."

This may feel a little awkward at first, especially if you’re used to letting your visuals speak for themselves. It takes some practice to balance clear narration with a natural delivery. But over time, most instructors find that using this more illustrative language also helps students who are new to the content and not just those with visual impairments.

You don’t need to describe everything. You only need to discuss what’s essential for understanding the material. The goal is for all students to be able to follow the logic and flow of your explanation, even if they can’t see what’s on the screen.

High contrast makes your content easier to read for everyone, not just students with low vision or color blindness. The simplest and most reliable approach is black text on a white background or white text on a dark background. If you use colored backgrounds or slide designs, just make sure the text still pops clearly against whatever’s behind it. Avoid color combinations that are hard to read, like yellow on white, red on black, light gray on white, or green on red (or any combination of red and green, really). See for yourself:

In a similar vein, if you're using charts, graphs, or data visualizations, don't rely on color alone to show differences. For example:

Examples of how to present accessible visuals.

Instead of... A graph with red and green lines representing two variables Try... Lines that differ in both color and shape (e.g., solid vs. dashed), or labels

Instead of... A pie chart with multiple shades of the same color Try... Distinct colors or add labels, patterns, or textures to distinguish each section

Which U.S. city has the largest population? A. Chicago B. Houston C. New York D. Phoenix Which U.S. city has the largest population? A. Chicago B. Houston C. New York ✅ D. Phoenix Instead of... Text highlighted in color only (“correct answers in blue”) Try... Correct answers are marked in blue and with a check mark

If you’re unsure about the readability of your slides, you could use a variety of free online contrast checkers or view your slides in grayscale to see if the information still holds up without color.

Ultimately, the goal isn’t perfection. It’s clarity. Just try to make visual information clear and distinct. When in doubt, simpler and higher contrast is always better.

While readability isn’t formally listed as an accessibility requirement, it strongly aligns with the goals of accessibility. If visual information is hard to read or overwhelming, it’s effectively inaccessible. This is particularly true for students viewing on smaller screens, in bright classrooms, with low vision, or suffering attention difficulties.

In other words, good design is accessibility. Limiting the amount of onscreen text you use, using large fonts, and organizing information cleanly all help ensure that students can focus on your message and not on decoding your slides. You can learn more about the cognitive psychology behind this principle in our article on best practices in presentation design.

Some general reminders:

• Use large text. If students in the back of the classroom (or watching on a phone) can’t read it, it’s too small.
• Use less text. Aim for no more than 3-4 concise bullets.
• Use clean sans-serif fonts. Arial, Calibri, and Helvetica are reliable. Avoid decorative or script fonts.
• Use images instead of text. If it can be represented with an image, use that instead — don't do both.

This is one of those "common sense" guidelines that most instructors already follow without thinking about it. The rule of thumb is pretty simple: if something on screen flashes rapidly (more than three times per second), it can pose a risk for certain viewers. So just don't do it.

In practice, this mostly means avoiding rapid animations, strobe effects, or flashing transitions in slides or edited videos. It’s also best to avoid automatically moving or scrolling text ("marquee" effects), which can be difficult for some viewers to read or track.

Most PowerPoint and video editing templates are already safe by default, so unless you’re deliberately channeling a 1990s music video aesthetic…you’re probably fine. But keep it in mind.