In the upcoming iOS 11 update, Apple has announced that it will be replacing JPEG files with a new image format called HEIF. So, why leave behind the industry standard of JPEGs, and what does HEIF have to offer? We investigate. Read next: iOS 11 preview

What is HEIF?

HEIF stands for High Efficiency Image Format. As the name suggests, it's a more streamlined way to store image files. Using advanced, modern compression methods it allows digital photographs to be created in smaller files sizes, all while retaining higher image quality than its JPEG alternative.

what is heif

HEIF is based on the HEVC (High Efficiency Video Compression) or H.265 video format already used on newer iPhones. HEIF isn't actually an Apple invention at all, but was developed by the MPEG group that was also responsible for the AAC format used in iTunes.

Technically, HEIF isn't really a format as such, more of a container for images and audio. The way Apple has outlined its use will be to store still images encoded with the HVEC (H.265) video format. This will work particularly well with Live Photos, as multiple images can be saved in the HEIF container. The same should also be true for dual camera images captured on the iPhone 7 Plus and the rumoured iPhone 8.

what is heif

What advantages does HEIF have over JPEG?

While JPEGs have been the faithful standard of online images for a quarter of a century, times have moved on. Replacing the ageing format with HEIF will mean that capturing photographs on iPhone or iPads will now take up a lot less of the inbuilt storage.

This is good news, as the increasing quality of images and videos (with 4K video now becoming almost standard) means that users are constantly having to watch how much space is left on their devices. Apple's adoption of HEIF should go a long way to alleviating this issue.

This reduction is down to the compression techniques employed by HEIF. In fact, the MPEG group claims that twice as much information can be stored in a HEIF image as a JPEG one of the same size.

So, presumably users will be offered the ability to store similar-quality images to the ones they're already accustomed to, but in half the space. Alternatively, they could opt for higher-res files at the same size as their current JPEGs.

The fact that HEIF also supports 10-bit deep colour images will come as a blessed relief for iPhoneographers who have seen those mystical sunset images compromised by ugly banding caused by the 8 bits currently on offer.

Will you still be able to share images with non-iPhone users?

Apple recently revealed that iPhone users take more than a trillion photographs each year, which is a pretty staggering number. But even with these huge figures, the truth is that the web and Android users still make up the bulk of people, so Apple won't be able to switch the world to HEIF just yet.

Instead iOS 11 will convert images to JPEG when you want to share them with non-iPhone-wielding friends, or for use on various social media sites.

Hopefully it won't be long though before we see HEIF adopted across the board. In an age where storage space is at a premium, it can't come fast enough.