iOS 11 introduced support for modern HEIF and HEVC codecs developed by the Moving Picture Experts Group (not Apple’s proprietary formats) that keep high-resolution photos and videos taken with iPhone and iPad from eating up all your available storage. This post tells you more about it.
Here’s what the acronyms stand for:
- HEIF: High Efficiency Image File Format
- HEVC: High Efficiency Video Coding
HEIF and HEVC offer better compression than JPEG and H.264 (AVC), so your photos, videos, Live Photos, panoramas, depth of field images, and pretty much anything you can take in the stock Camera app will take up half the space without sacrificing image quality.
Being able to take more photos and shoot longer 4K videos before your iPhone or iPad fills up is going to make owners of lower-capacity devices very happy.
And, you don’t have to think about compatibility when you open HEIF/HEVC media in other apps or send these files to non-Apple devices through the Share Sheet because in that case, iOS will automatically transcode them into a more compatible JPEG/H.264 format.
To the user, everything works just like before, though, of course, you must be running iOS 11 or macOS High Sierra or later to view, edit or duplicate HEIF/HEVC media captured with an iOS device.
HEIF/HEVC file formats
HEVC, also known as H.265, is a codec for both images and videos. HEIF is a file format for images encoded with HEVC.
- HEIF images: Saved with the .heic extension.
- HEVC videos: Saved with the .mov extension, like regular iPhone videos, but compressed using the much more efficient H.265 codec.
HEVC videos use .MOV files as the container, just like H.264, MP4, and MKV videos.
Now let’s get to the meat of the matter.
Support for HEIF/HEVC is built into iOS 11, macOS High Sierra, and later, letting you work with this media in a variety of apps, like Photos, Preview, QuickLook, and QuickTime Player. All devices running these versions of iOS or macOS can display HEIF images without issues.
Although baseline iOS 11 devices can play back standard 1080p HEVC clips, watching 4K HEVC clips without stuttering and in a battery-friendly manner requires hardware acceleration provided by Apple’s A9 chip or newer (iPhone 6s and up, all iPad Pros and 2017 9.7-inch iPad) or Intel chips in 2017 Macs and up.
As an example, using Photos on my iPod touch to play a 4K HEVC video led nowhere. All I could do was stare at the spinning wheel as its A8 chip struggled to decode the file.
On older devices without hardware acceleration, support for HEVC is affected by the resolution and frame rate of the video:
- iPhone 6, iPhone 6 Plus, and iPad Air 2 work with HEVC video that was captured at no greater than 1080p at 240 fps.
- iPhone 5s, iPad Air, and Retina iPad mini models work with HEVC video that was captured at no greater than 1080p at 60 fps or 720p at 240 fps.
- Mac models from mid-2015 or earlier work with HEVC video that was captured at no greater than 1080p at 240 fps.
What if you use iCloud Photos, but your iPhone, iPad, or Mac can’t fully view, edit or duplicate HEIF/HEVC media because it lacks hardware support?
In that case, iCloud Photos will send your HEIF/HEVC media at a lower resolution to ensure the files can be displayed on those devices, and you might see a warning message in Photos.
iCloud Photo Library or iCloud Photos, of course, always preserves your HEIF/HEVC files and other media in their original format, resolution, and frame rate.
To take HEIF images and HEVC videos, you’ll need at least Apple’s A10 Fusion chip. When using iOS 11, the following devices can capture media in HEIF or HEVC format:
- iPhone 7 or iPhone 7 Plus or later
- 10.5-inch iPad Pro
- 12.9-inch iPad Pro (2nd generation) or later
On supported hardware, iOS 11’s Camera app defaults to HEIF/HEVC capture.
Selecting camera capture format on iPhone
You can toggle between HEIF/HEVC and good ol’ JPG/H.264 in Settings > Camera > Formats, then choose your preferred camera capture format:
- High Efficiency: Encode photos/videos you take using the HEIF/HEVC codec.
- Most Compatible: Always use JPG for images and H.264 for videos.
Note: If you don’t see this section, your device doesn’t support capturing in HEIF/HEVC.
If you tap High Efficiency, all new photos and videos you take on this device will be encoded in the space-saving HEIF and HEVC media formats.
Going with “High Efficiency” gets you half smaller videos/photos without losing quality.
Though capturing in HEIF/HEVC format is recommended, it’s good that iOS gives you the option to capture media using the older JPG/H.264 formats that are more broadly compatible with other operating systems and devices.
Here’s a little experiment that illustrates the storage savings provided by these codecs.
File size shootout: HEIF/HEVC vs. JPG/H.264
Having set the iOS capture format to HEIF/HEVC, I took eight images with my iPhone 7 Plus and a one-minute 4K video at 60FPS. I exported everything to my Mac via a USB cable and macOS’s Image Capture app.
Then I told iOS to convert the originals into JPG/H.264 files during export. Comparing the “before” and “after” file sizes in Image Capture revealed a startling difference.
Photos/videos taken with my iPhone 7 Plus in standard H.264/JPG formats.
The same captures made using HEVC/HEIF. Note the significant difference in file size!
If that wasn’t enough to sell you on the storage-saving benefits afforded by these codecs, that’s because you’re probably thinking, “I’d rather turn the whole thing off because what about HEIF/HEVC sharing with Windows and folks with slower hardware?” right?
Don’t worry. Apple has thought of that, too.
Choosing media export format on iPhone
You can set iOS to always export your HEIF/HEVC media to a computer in the original format or to convert the media, if necessary, to a more compatible JPG/H.264 format.
Go to Settings > Photos and make that choice below the Transfer to Mac or PC heading:
- Automatic: Automatically transfer photos and videos in a compatible format.
- Keep Originals: Prevent HEIF/HEVC media from being converted to JPG/H.264 when importing to a computer via USB.
If you choose Automatic, your HEIF/HEVC media might be converted to JPEG/H.264 when exported via USB from an attached iOS device to a PC and Photos or Image Capture on a Mac.
Because it “just works,” the Automatic setting should always be enabled.
But if you need to transfer your HEIF/HEVC items to a computer in their original format, select Keep Originals to prevent the media from being converted when importing.
Sharing HEIF/HEVC media
To save you from compatibility conflicts, both iOS 11 and macOS High Sierra automatically transcode HEIF/HEVC items to JPG/H.264 when using the Share sheet or other methods to send them to:
- Devices running older iOS and macOS editions
- Non-Apple devices
- Social media services
- Apps that don’t support HEIF/HEVC
You don’t have to do anything special; just share your media like before.
The HEIF/HEVC → JPG/H.264 conversion happens on the fly and without changing the originals in the Photos app. Any transcoded files get discarded upon sharing to save space.
For instance, picking a few HEIF images in Photos and sharing them to Mail will prompt iOS to attach JPGs. Similarly, if you send a 4K HEVC video to a friend’s iPhone 7 using AirDrop or iMessage, he’ll receive it in the widely compatible H.264 file.
Wrapping it all up
Summing up, Apple went all-in with HEIF/HEVC in iOS 11, tvOS 11, and macOS High Sierra. These codecs will be with us for years to come and have a lot going for them, like non-destructive cropping and rotation, support for 4K/8K/3D videos, and more.
Stay tuned to iDownloadBlog as we’ll be diving deeper into these media formats and discussing what they mean to you and how they help future-proof Apple’s platforms.
BOTTOM LINE: HEIF and HEVC keep file sizes low without degrading image quality.
Your HEIF images and HEVC videos sync with iCloud faster, support non-destructive manipulations in Photos and, ultimately, free up storage space so you can shoot even more photos and videos or fill your devices with more apps and content you care about.
Are you sold now?
Check out next: