What You Need to Know About HEIF in macOS High Sierra and iOS 11

MacRumors

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Original poster
Apr 12, 2001
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With the official release of iOS 11 and macOS High Sierra, Apple introduced support for a new image format called HEIF. Apple sees HEIF as a worthy successor to the JPEG format. So what makes it so good that it can replace an industry standard that's been in use for almost 25 years?


What is HEIF?

HEIF stands for High Efficiency Image Format and can be considered the still-image version of the HEVC video codec that Apple's ecosystem now officially supports. (You can learn more about HEVC here.) The HEIF standard wasn't made by Apple - it was developed in 2015 by the MPEG group, which also invented the AAC audio format used in iTunes.

Benefits of HEIF Over JPEG

As the name implies, HEIF is a more streamlined method of storing image data and offers better quality than the traditional JPEG format. For example, HEIF supports image transparency and can capture a more extended color range than JPEG (16-bit versus 8-bit), which should increase the accuracy of photos taken on Apple's latest iPhones. At the same time, a HEIF-encoded image should be around half the file size of an equivalent-quality JPEG, so users will be able to keep twice the number of shots on their Apple devices (or in iCloud) before they max out their storage capacity.

In addition, HEIF files include a 320x240 embedded thumbnail that's four times the resolution but only twice the file size of a standard JPEG thumbnail. HEIF images can also be rotated and cropped without altering the image or re-saving them, all of which makes working with HEIF files that much faster than JPEG on both Mac and iOS devices.


HEIF also brings other benefits that JPEG doesn't offer because it's unlike your typical image format. That's because it's also capable of acting as a container for multiple files. This should be a boon for anyone who takes bursts of photos or lots of Live Photos - which can be edited in multiple new ways in iOS 11 - but it also means HEIF could become a wholesale replacement for GIF.

HEIF Compatibility and Image Sharing

Currently, Apple only supports HEIF image encoding on iOS devices with a minimum A10 Fusion processor, so that includes the 2017 10.5-inch and 12.9-inch iPad Pro, the iPhone 7 and iPhone 7 Plus, and of course Apple's new 2017 range of iPhones. Owners of these devices can check their camera is encoding photos in HEIF by going to Settings -> Camera -> Formats, and ensuring the "High Efficiency" option is selected. The "Most Compatible" option means photos will be encoded in JPEG format.


HEIF is supported on all Macs capable of running macOS High Sierra, and many macOS applications work natively with HEIF, including Photos, Preview, and Quick Look. This means macOS users might consider converting their JPEG image files to HEIF for greater storage or network benefits.

The transition to HEIF within the Apple ecosystem should be mostly transparent, but if users need to move HEIF content outside of that ecosystem, it's worth looking into transcoding options (JPEG, for example) to provide the best backwards compatibility for other users. Happily, iOS 11 will auto-convert HEIF images to JPEG when they are shared to devices running earlier versions of iOS, non-Apple devices, and popular social media sites, or when they are passed over to apps that don't yet support the standard.

Article Link: What You Need to Know About HEIF in macOS High Sierra and iOS 11
 

farewelwilliams

macrumors 68020
Jun 18, 2014
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9,693
"What you need to know"

I need to know how this works when my parents are using iCloud Photos + Windows. They aren't "sharing", but they download photos from iCloud to their computer all the time.
 
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macTW

Suspended
Oct 17, 2016
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Really does sound like the future of image storage.

Maybe I should buy the 64 GB phone instead...
 
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garirry

macrumors 68000
Apr 27, 2013
1,540
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Canada is my city
Wait, only on A10 devices and up? That's BS. Considering that so many iOS devices out there are 32 GB and 64 GB, support for encoding HEIF and HEVC is really important if you don't want all your storage to be filled within days.
 

izyreal

macrumors regular
Sep 26, 2012
171
405
USA
Does this upgrade the camera on my 7 Plus? The article says my photos will be “better quality.” What does that mean?
 

badbrain

macrumors newbie
Sep 21, 2017
13
7
Literally ½ the file size for same or better quality photos. Same with HEVC for video (excellent for 4K)

Only works on newly taken videos/photos AFIK.

Google photos also supports both, which I find to be an excellent free cloud option. Any windows users can use that on a desktop to view uploaded photos/photos on PC.
 

killawat

macrumors 65816
Sep 11, 2014
1,446
2,191
Half size is enticing. I plan on using GraphicConverter v10.5 to move some of my files over to HEIF, then do a batch convert once I'm convinced.
 

Iconoclysm

macrumors 68020
May 13, 2010
2,346
1,546
Washington, DC
Wait, only on A10 devices and up? That's BS. Considering that so many iOS devices out there are 32 GB and 64 GB, support for encoding HEIF and HEVC is really important if you don't want all your storage to be filled within days.
Perhaps it requires more processing power to encode them? Perhaps the A10 includes a hardware encoder?
 

SamVilde

macrumors regular
Oct 18, 2008
159
70
New York City
Still don’t understand.

It sounds better, but does this mean I’ll have to ask everyone I want to share photos with what kind of device(s) they’ll be viewing it on?
 

Peel

macrumors 6502a
Aug 30, 2004
572
84
Seattle
The iCloud Photos viewer that is part of iCloud for Windows does not convert the images. I open the Downloads folder and see all of my images as a combination of IMG_xxxx.HEIC and IMG_xxxx.MOV files. One pair for each image that I took (I have Live Photo turned on, so I'm guessing that's why there's an MOV file).
 

reallynotnick

macrumors 6502a
Oct 21, 2005
870
278
Does this mean that JPG -> HEIF conversion is completely lossless? Because if it's not, NO, macOS users shouldn't convert their images.
It's not, and unless you like losing picture quality I wouldn't suggest doing it. You can't convert lossy -> lossy without quality loss. I'll use it going forward but I'm keeping all my old images as JPGs.
 

Music Ambulance

macrumors regular
Oct 31, 2008
120
65
It's not, and unless you like losing picture quality I wouldn't suggest doing it. You can't convert lossy -> lossy without quality loss. I'll use it going forward but I'm keeping all my old images as JPGs.
If this truly is a lossy format I’d suggest macrumors revise their article, that converting old files will damage them
[doublepost=1506372741][/doublepost]
i wonder if all web browsers support HEIF already
I’d assume that could take ten years.
 
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Cosmosent

macrumors 6502a
Apr 20, 2016
957
1,030
La Jolla, CA
HEVC-encoded images (& image sequences) in a HEIF container provide two benefits:

1.) ~33% (real world) reduction in file sizes & streaming requirements, &

2.) support for 10-bit extended color spaces !

#2 is actually a bigger benefit than #1, but ALMOST ALL who have written about HEIF & HEVC today have missed it, BIG TIME !

---

Also, for those who have an interest:

"Deeper Pixels" = 3 Apple mobile devices (A11 ONLY) ... for those of you who don't know, this refers to camera "capture" in 10-bit extended color spaces, and NOT just Apple's Display P3.

HEVC Encoding = 7 Apple mobile devices (A10, A11, A10X).

Wide Color = 8 Apple mobile devices (A10, A11, 9.7" iPad Pro, A10X).
 

IGI2

macrumors 6502a
May 6, 2015
508
464
Wait, only on A10 devices and up? That's BS. Considering that so many iOS devices out there are 32 GB and 64 GB, support for encoding HEIF and HEVC is really important if you don't want all your storage to be filled within days.
They still made the change fairly early.

Older iPhones doesn't have energy-efficient-enough chips to encode in HEVC. Battery is already a burning problem, I'm sure people wouldn't like to degrade it even further.
[doublepost=1506408031][/doublepost]
If this truly is a lossy format I’d suggest macrumors revise their article, that converting old files will damage them
[doublepost=1506372741][/doublepost]
I’d assume that could take ten years.
It can be lossy and it can be lossless. However, it is most likely to a 2 MB JPEG would result in 15 MB HEIC if you wanted to do it lossless.