One of the novel features Apple added to the iPhone 6s to distinguish it from its predecessor was Live Photos, where every photo you take is effectively a very brief video, capturing the movement and sound as the photo was taken. The feature is unique to the 6s as it’s activated by a 3D Touch. Today, we’ve learned a little more about the simple yet clever technology behind it.

As you may already know, existing iPhones start taking photos the moment you open the app. This is how Apple provides the camera with the ability to take photos instantly, with none of the delay (‘shutter lag’) you see with some digital cameras. The camera has already taken and temporarily stored a whole bunch of photos, and it simply keeps the last one taken as you press the button and discards the rest … 

What Live Photos do is save enough of these before-and-after photos to create a 1.5-second animation. It’s not video, it’s just effectively an animated GIF in JPEG format – a similar approach to Motion JPEG. Audio is recorded separately and then attached to the animation. The animations can be set as your iPhone wallpaper.

Details of the file format were tweeted by Daniel Matte after speaking with an iPhone product manager, and are consistent with a brief description in Apple’s iOS Developer Library.

Apple said in the keynote that Live Photos were very space-efficient, and TechCrunch reports that Live Photos only take up around twice as much storage space as standard photos. This is likely because little will change between frames, so each subsequent photo file saves only the differences from the previous frame.

What’s your view of Live Photos – a novelty that will quickly wear off, or a feature you’ll really appreciate? Take our poll and let us know your thoughts in the comments.

Via MacRumors