What is Closed Captioning? Difference from Subtitles

An explanation of closed captioning and how it differs from subtitles, open captions, and SDH.

If you are a foreign video content aficionado, you might already be familiar with subtitles. But what is closed captioning?

Closed captioning transcribes not only the dialogue in a video but also other audio sounds and non-speech elements. This process makes the video accessible to the deaf and hard of hearing, increasing the reach of your content.

What does Closed Captioning Mean?

The closed captioning process displays text reflecting the audio track in a synchronised manner, so it can be read while watching the visual content. It involves transcribing the audio into text, dividing it into caption frames, and synchronising those frames with the video.

Captions generally appear at the bottom of the video and include dialogue, relevant sound effects, and other elements. This helps communicate the audio to the hard of hearing and deaf. Users can change the display and placement of these captions so that visual images are not obstructed.

Closed Captions vs Open Captions

Captioning is the process of adding text to a video that explains what is going on (read how to add captions to videos on social networks).

The main difference is that open captions cannot be switched off, while users can turn closed captions on or off. When closed captions are used for movies and TV, decoders are usually needed.

Deciding between the two depends on the experience you want to deliver. Because of the flexibility of closed captions, users are always in charge and can view the content however they want. Open captions may be distracting, but they offer better comprehension and accessibility because they are permanently visible.

Difference Between Subtitles and Closed Captioning

Although subtitles and closed captions are often used interchangeably, they are two completely different processes.

Subtitling provides text for the dialogue in the video and the words spoken by the narrators and characters. Closed captions provide text not just for dialogue but also describe the audio cues, background noises, and the scene.

Subtitles are usually used to translate the video for foreign audiences: the audio is preserved, but the dialogue can be understood through the subtitles. Captioning, on the other hand, is used for audiences with impaired hearing, who need a description to provide more context.

Subtitles for the Deaf and Hard of Hearing

While SDH subtitles and captioning serve the same audience, there are several differences between the two, mainly in how they are formatted and displayed.

Captions are usually displayed as white text on a black background and can be positioned anywhere. SDH can vary in colour and is displayed at the bottom of the screen.

SDH can be turned on or off, and the fonts can generally be adjusted if the viewer prefers larger or smaller text. Captions are displayed permanently on the video.

Closed Caption Formats

There are several file formats used in captioning, based on their application and the device used. Here are some of the most common formats and their use cases:

Closed Captioning Quality and Accuracy Matters

In many videos, automatic captions do not make sense because there is a noticeable discrepancy between what the captions display and what is said in the original video. This can negatively affect the viewer's experience. Since closed captions are a way for those with hearing loss to access a video, quality is important.

For captions to be of good quality, they need to be readable, 99% accurate, and not obstructive. Accuracy measures the grammar, spelling, and punctuation in the text. The industry standard is a 99% rate of accuracy, allowing leniency for 1% errors, whereas automatic speech recognition typically only reaches an 80% accuracy rate.

This is one of the most important reasons to hire a captioning vendor that delivers 99% accuracy, so the end result provides a high-quality viewing experience.

Automatic Speech Recognition (ASR)

ASR, or Automatic Speech Recognition, is a technology that automatically transcribes speech in a video. ASR is cheap and fast compared to humans, but the transcripts often lack quality and can have many inconsistencies.

ASR typically does not provide transcription for non-speech elements that are critical, and it may omit punctuation and grammar, affecting reading comprehension. While ASR can be used to create a rough draft, it is essential to edit and review the transcripts thoroughly with the help of a captioning professional to ensure quality and accuracy meet industry standards.

Hire Closed Captioning Services

Closed captioning is a complex, specialised service that requires professionals with extensive experience. GoLocalise has a team of captioning experts who can provide services in over 100 languages.

We understand how much quality and accuracy impact the viewing experience of those with impaired hearing. Our stringent quality control processes ensure that all files are thoroughly checked before delivery, and our in-house project managers and captioning experts use industry-standard software to ensure accuracy. With more than 15 years of experience, GoLocalise can deliver perfectly synchronised and accurate captions for your project.

If you still have doubts about what closed captioning is, get a quote and reach out to us.