To help with those who have auditory impairment issues, or for situations where it is difficult to hear the audio, captions really come in handy. There are two types of captions you can use: open captions and closed captions. Author Richard Harrington suggests things to consider for when you are deciding to use one or the other.
- To help with those who have auditory impairment issues or for situations when it's difficult to hear, captions really come in handy. But there are two types of captions, open captions and closed captions. Let's take a look at what a caption is and then the different types. Essentially, with captions, what we're looking for is an onscreen text description. Now this is a bit different than subtitles that you might see in a movie. Subtitles are typically used for language translations, such as when watching a foreign film.
A caption describes the audio and often sounds or that music is playing. These are useful for showing things such as dialogue, identify who's speaking, and describe other relevant sounds. Captions tend to be synchronized with the video image. Web video can have open or closed captions. This means that either is acceptable. One type of caption is a closed caption.
Closed captions can be turned on or off by the viewer. This means that the person watching is in control of whether or not captions are visible. For video on televisions, you need a special device called a decoder in order to view the captions. Typically, captions are injected into the video stream and carried over the broadcast signal. Now for many years, the decoders have been built into television sets, and this has been a requirement that they ship this way.
Another method is an open caption. In this case, it appears on the screen. These tend to be viewable inside of a media player. In order to be 508-compliant though, the viewer must be able to turn the captions on or off, which is the closed caption method, or the captions have to always be visible, which is the open caption method. Keep in mind that if you choose open captions, many people make two different files available for download, one with the captions, and one without.
Additionally, captions that are used for closed captioning can often to converted into open captions using software. For example, Adobe Premiere Pro can do this when exporting a video file. It can take the caption stream and turn it into open captions. Now here's one example for you. This is a podcast from the National Parks Service, and in this case, you'll notice that with the video, they've indicated that this is available with open captions.
Sometimes, they'll make them available with some with and some without, mixing it in the single podcast feed. As you can see, some folks include open caption content in a podcast. This is because the caption format wasn't always supported by iTunes. However, sites like YouTube tend to be a little bit better at supporting closed captions. Let's take a look at an example from the National Parks Service. - [Narrator] Did you know that for the last 303 yards from the Rim Road to this overlook, you have been walking on Vernal Mesa Quartz Monzonite? This rock unit is composed of some of the most common minerals known on earth, including feldspars and quartz.
Feldspars are the most widespread mineral group because they can occur in all types of rocks and constitute 60% of the earth's crust. White, gray, and pink are common colors for fledspars. Quartz is the next most common mineral on earth. - Now you might be wondering, how do I choose which method is best? Well, there are pros and cons to each, and you'll need to decide which one works better for your particular situation.
Keep these things in mind. Open captions are always in view and cannot be turned off. This means that if you have to ensure that compliant video is being delivered. In this case, if you have to ensure that accessible video is always being delivered, the open caption format means you are always in compliance and making the video more accessible. Open captions are an actual part of the video stream. They are embedded in the video file.
The challenge here with open captions is a spelling error is a problem with the video, or if there is an edit made and you need to make a fix, or you identify that someone's name was spelled incorrectly. Well, it's burned into the video and hard to update. Open captions, unlike closed captions, are also subject to a loss of quality when a video file is compressed. Open captions can be compressed. Remember, a video file, when delivered to the web, is typically heavily optimized.
That means that high-contrast areas, like text, might be subject to heavier compression, making it more soft at the edges or difficult to read. Closed captions exist as a separate text stream. This can be useful because it's easy to edit since it's an independent file. Or you can have multiple captions available, in this case providing different languages or translations. Closed captions only appear only if a media player supports them.
So you have to make sure you're using a compatible media player. If captions are preserved as text, it can be searchable as well. This is a huge benefit, because it means that when a page is indexed by the search engine, well, that content becomes part of the relevance. That means that content in the video is now properly indexed, increasing how easy it is for someone doing a web search to find it. And some players even allow you to click on a word and queue up the video.
For example, the video you're watching on this site might support that feature if you take a look at the transcripts feature. Now there are a wide range of tools out there at greatly different price points. Here are a few that I've tried. Amara.org is an organization that provides different types of captioning tools, including some free ones that you can download and use yourself. Tools like CaptionMaker, Caption Creator, and iCaption tend to be highly affordable. On the other hand, tools like MacCaption and CaptionMaker are robust tools for broadcasters, but come with equivalent price tags.
You can find captioning software available in a wide range of prices, with vastly different features, but I would recommend that you pick up a tool to use. I showed you one earlier, how it allowed me to open up a movie, import a text file, and generate my own captions. This is useful in case you need to do this yourself, because hiring an outside vendor isn't practical due to time constraints or financial considerations.
- What is accessibility?
- Understanding accessibility needs and issues
- Working with scripts and transcripts
- Optimizing video for visual impairment issues
- Optimizing video for audio impairment issues
- Captioning in Adobe Premiere Pro
- Captioning in Digital Anarchy Transcriptive
- Captioning in Final Cut Pro X
- Including captions and transcripts on web and social media video