THEY say a picture speaks a thousand words. Now pictures on Facebook and Twitter can speak to people who have vision impairment.

The social media companies have launched new technologies so people with sight loss can be included in the photo sharing trend that has swept the world.

According to Facebook, people share more than two billion photos across Facebook, Instagram, Messenger and WhatsApp every day.

But with almost two million people in the UK living with some form of sight loss, many people may feel excluded from the conversation around photos.

Facebook, whose daily login rate has risen to more than 1 billion people a day, has launched automatic alternative text, or automatic alt text, to generate descriptions of photos posted on Facebook so people with sight loss can know what is in the many photos that pop up in their news feeds.

Before the new technology was launched this month, people using screen readers would only hear the name of the person who shared the photo followed by the term photo when they cam up in the news feed.

A Facebook statement said people using screen readers on iOS devices would now hear a list of items a photo may contain as they swiped past photos on Facebook, such as ‘Image may contain three people, smiling, outdoors’.

Twitter has also added a feature that makes pictures accessible to visually impaired people.

Twitter users on iOS and Android apps are now able to add descriptions, of up to 420 characters, to their photographs to aid assistive technology for blind people.

The descriptions, or alternative text, will be available on technology including screen readers and braille displays.

People can access this feature by using the compose image descriptions option in the Twitter app’s accessibility settings.