YouTube is making auto-captions available on all its hosted videos.

Video-streaming website YouTube is to add automatic captions to its videos in order to make them more accessible to people who deaf and hard of hearing.

Announced on its blog yesterday (4 March), YouTube is opening up auto-captions for all videos hosted on the Google-owned website.

According to YouTube, tens of millions of people in the U.S. experience impaired hearing and recent studies have predicted that over 700 million people worldwide will suffer from a hearing impairment by 2015.

In November 2009, YouTube released the auto-captioning programme for a small group of partners. The YouTube auto-captioning “combines some of the speech-to-text algorithms found Google’s Voice Search to automatically generate video captions when requested by a viewer”.

Video owners now have the opportunity to request auto-captions for their video, although the process may take some time.

As the programme uses a speech recognition application, only videos with a clearly spoken audio track will be able to have captions. Even with clear audio tracks, YouTube cannot guarantee the accuracy of the captions provided.

Only English language captions are currently available but YouTube hopes to open up the programme for other languages in future months.

The company said: “Making some of these videos more accessible to people who have hearing disabilities or who speak different languages, not only represents a significant advancement in the democratisation of information, it can also help foster collaboration and understanding.”