What's the different between subtitles, SDH and closed or open captions?

It's important to know the difference between the four types of subtitles, to make sure you’re getting the best possible option for your content and budget. It may seem like complicated industry jargon, but we're going to lay out exactly what each one means, and which subtitling service you may need.

First things first, what are closed and open captions and how do they differ?

What are closed captions?

Simply put, closed captions are captions which can be switched on and off. For example, captions you can switch on and off on your television, or captions you can switch on or off through online media players, such as YouTube's or Vimeo’s video players. Here's an example from YouTube:

The type of file you will need is called an .SRT - this would cover you 99% of the time for online content. Some other common file types you might run into are WebVTT (sometimes abbreviated to VTT), YouTube SBV (the file that YouTube outputs if you have files in their captioner) and .XMLs (the subtitle files that Netflix uses). For TV it's more complicated, but we'll get into that later.

What are open captions?

Open captions are the opposite - they can't be switched on and off. They are "hardcoded" into a media file and can't be removed, meaning they’re fused together. Another word we use for this process is burned in.

For video editors out there, you actually use a closed caption file to create an open captioned video, by dragging the closed caption file onto your timeline in Premiere Pro or Final Cut Pro and exporting the video as you normally would.

Think of it like this:

Closed captions (or subtitles, or SDH) + video = open captions.

Let's say you want the ability to turn the captions off rather than "burn" them in, so we'll take a look at the terminology and why they're different.

What's the difference between closed captions and subtitles?

Subtitles are meant for people who can hear (also great for language learners), and that's why things like music being played, or the description of sound effects, or labelling of speakers isn't included or required. 

As closed captions are for hard-of-hearing audiences, everything that is important to telling the story in a video must be displayed through text. This is why you need to identify speakers, describe sound effects and indicate when music is being played.

What are SDH subtitles?

SDH (Subtitles for the Deaf and Hard of Hearing) are also very similar. The difference is in the way they are displayed, the placement and support of HDMI (closed captions are not supported through HDMI).

It's important to bear in mind that when it comes to online content you will most likely only deal with either regular subtitles, or SDH; it's more complicated once you delve into broadcast media.

Here is our full comparison table:

Still unsure what you need for your project?

Get in touch at hi@subtitleall.com so we can have a no-obligation chat about your video content.