What are closed captions?

what are closed captions image

What are closed captions?

You probably already know what closed captions are, they’re effectively subtitles that can be switched on and off on a video file. Be it from their inception on TV and VHS tapes in the 80s and 90s to DVDs, Blu-Rays and online content most of us consume day to day on platforms such as YouTube, we all have seen that little [CC] symbol everywhere.

Closed captions are just the written depiction of what can be heard and what is being said on a video. Closed captions are usually displayed as lines of text on the centre-bottom of a screen and displayed synchronised with the footage.

These captions usually consist of dialogue and occasionally descriptive text for background noises, music and sometimes even the inflection of the way certain things are being said.

Closed captions are closed because as standard, they are not visible unless the option is turned on by the consumer, which was a main requirement so as not to detract from the content for those who do not want or require it.


History of closed captions

Prior to closed captions were open captions; however, these were not widespread at all.  Open captions are hard coded into a video file and cannot be turned off. This is your traditional subtitle used for silent movies and exported films to allow none-native speakers to watch and enjoy cinema, films and tv shows worldwide.

With the invention of the TV, you would have thought that the main benefit would be to allow those who are hard of hearing to gain some benefit popular entertainment mediums such as radio, which seemed to be the logical progression.

However, it wasn’t until 1971 (44 years after the invention of the TV, and almost 2 decades after TVs became commonplace) that the first closed captioned TV show first aired, and it was only a demonstration. A fully closed-captioned series wouldn’t air until 1972’s The French Chef in the USA.

The BBC were the first station to introduce widespread closed captions in 1979 with their ground-breaking Teletext framework for pre-recorded programming.

Other networks followed suit throughout the 80s and 90s and with digital signalled television streams, more options to push closed captions became apparent and by 2010, BBC offers 100% broadcast captioning services across all of its main broadcast channels.

With the internet came a slew of video platforms, be it from Dailymotion to Vimeo and the world’s largest video platform, YouTube, all of which benefitting from closed captions.


Methods of closed captions


After a video has been made and before it is aired, streamed or uploaded to a video content site, the closed captions are inserted to the video file as a separate data stream to allow for switching captions on and off.


These captions are created real-time.  Examples include speech recognition engines such as Microsoft Azure (utilised in some of Accuro’s services) provide real-time captioning of sportinv events, newscasts etc. that do not allow for the preparation of high-quality, accurate captions.


Captioning styles

Closed captions example fox image

Closed captions

The classic closed captions, white text on a black background.  These are hidden as standard but can be made visible by choosing the option on a TV or online video platform.

Subtitles track example image with fox

Subtitle track

Subtitles are usually white or yellow with a black line or drop shadow on them. They are implemented the same way as closed captions in online content, as a separate track.  Accuro can provide captions in other languages using their professional translation service in conjunction with their captioning service.

An example image of SDH subtitles track

SDH subtitles

Very similar to closed captions, SDH (Subtitles for the Deaf and Hard of Hearing) include information such as sound effects, speaker identification and other features that help provide context. 

Why add closed captions to YouTube videos?

Creating accessible, optimised, quality content, videos should be produced and delivered to high standards and to ensure that people can access, understand and enjoy your content. 

To understand why adding closed captions to YouTube videos is essential, you can read Accuro’s blog dedicated to investigating this more thoroughly.

Accuro’s YouTube captioning service boasts a team of experienced transcribers who will always produce a more accurate output than a speech recognition engine. You will see an uplift in accessibility, view time and search engine optimisation of your content.  Our pay-as-you-go charging structure makes the service affordable with no upfront costs or hidden fees.

These captions can be provided in either. vtt or .srt format and Accuro also have a detailed guide on how to add closed captions to your YouTube videos.

To find out more, contact Accuro today by either filling out our contact form or calling us today.

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