Nicholas Warren
Jul 09, 2020 5 minute read

HEIC

What is HEIC

HEIC is the container format (read file extension) for the HEIF format. Still confused? Well lets look a little deeper. HEIF stands for High Efficiency Image Format, it's a new technology using modern compression techniques to store an image. It's replacing the older and established JPEG format that has become the standard for storing images. Since 2017 Apple switched to using HEIC as the default image codec on all supported iOS devices.

So if JPEG is so established why make the change to HEIC. Well as more modern concepts and techniques have been developed it's possible to do things with the HEIC that JPEG just isn't able to. The key benefit to most people though is the fact that HEIC files are up to half the size of a JPEG image but retains the same visual quality. That means as we take more and more photos on our devices they are taking up less physical space. It also makes them easier and quicker to share over the internet.

Other Advantages

HEIC uses a 16 bit container instead of the standard 8 bit container which along with allowing greater image fidelity also alleviates banding in areas of an image with smooth gradations (like sunset skies for instance). It is also able to store a sequence of images, which Apple uses for it's Live photos feature. HEIC can also store image properties, depth maps (useful for portrait mode), alpha channels and HDR data.

Sounds Great so what's the Holdup

Unfortunately as it's a new image format adoption for it is not widespread. Versions of Apple's software prior to High Sierra and iOS 11 don't understand them. Windows has added support under Windows 10, but only if you download and install the relevant plug in and Android has only recently added support to it's OS. So how do I send an HEIC picture to someone else who doesn't own a capable device?

Backwards Compatibility

Apple knew this would be an issue from the outset so have given the user options that allow for converting the HEIC file into a JPEG when sending it to someone on an unsupported platform. This is most easily supported on the Share sheet in the iOS device where the HEIC image is stored:

  • Airdrop - If you share to another Apple device then the file stays the same, and the other device receives an HEIC file. This is even the case if the device is running an operating system that doesn't support HEIC, so when sending to an older device you may want to convert the image to JPEG first.
  • Messages - Using messages to share your image will automatically convert it to a JPEG, even if you are using iMessage or on a device that supports HEIC.
  • Mail - Again when sending an image via the Mail app it will automatically convert to JPEG for most compatibility.
  • Other apps that you may have on your share sheet will have to have implemented their own strategy, but the general rule of thumb is to assume that the image is getting converted to JPEG, unless it is one of Apple's built in apps such as notes.

I Want to Send an HEIC File but It Keeps Getting Converted to JPEG!

Sometimes you may find yourself wanting to send the actual HEIC file, but how do you do this. Well if you are on an Apple device then sending via Airdrop is the easiest, but this requires you to be in close proximity to the receiver.

The second option would be to save the file to iCloud drive (use the share sheet to save to Files and select a location on your iCloud drive). Once on your iCloud drive you can use other software to send the file direct or share a download link for it. In some cases you may have to zip the file before sending it to make sure that a conversion step isn't performed.

If you are sending the image via Apple mail make sure you select original image from the Image Size drop down or a conversion to JPEG will be made.

The Image Size drop down options in Mail. Original Image selected.

I Need to Send a JPEG Not HEIC!

At other times you may find that you want to use a JPEG and not an HEIC file. For instance you may want to add an image from your Photos library to an online service. They may not recognise the file type, or will convert it incorrectly automatically (for instance mis-read the orientation). In these cases we may want to deliberately convert the file to a JPEG.

On iOS and iPadOS

  • Make an edit to the photograph in Photos. If you make an edit to a photograph Photos will store the original file but produce a JPEG with the edits. When you use the file it sends the JPEG edited file instead of the HEIC original.
  • Take the photo in to an editing app such as Affinity Photo and use it to make a conversion to JPEG.

Visually Identical Conversion

In Photos if you want to make a conversion to the file but not visually change it then hit the edit mode, change the orientation and commit the changes. Then hit the edit mode again and change your orientation back to the 'correct' orientation before committing the changes again. Now you will have a JPEG file that is the same as the original.

On the Mac

  • Using Photos or Preview select File>Export and make sure to choose the JPEG file format in the export options.
  • From Photos drag the thumbnail of the image you wish to convert out to the Desktop/Finder window or to the location you wish to place the converted image. Photos will provide a JPEG version of the file.

I don't want to have to bother with any of this. What do I do?

Over time as the HEIC format gets adopted by more and more services and devices it won't be an issue, and to a large degree the OS takes care of it for you at the moment, but if you just want to make your iOS device takes photographs in the older JPEG format then you can tell the camera app to do this.

  • Select Settings>Camera>Formats
  • Make sure the tick is on the Most Compatible option. This will make sure that photographs are taken and stored in the JPEG format from this point on.
  • Please note that photographs that were taken previously in the HEIC format won't be changed to JPEG. This will make sure that any new photos are made using the JPEG settings.
The image format options of camera settings in iOS. The image format options of camera settings in iOS
Devices Capable of Taking HEIC Pictures

Using iOS 11 or later the following devices will take images in HEIC format by default:

  • iPhone 7 and 7 Plus or later
  • iPad (6th generation) or later
  • iPad Air (3rd Generation)
  • iPad Mini (5th Generation)
  • iPad Pro (10.5-inch), iPad Pro (11-inch)
  • iPad Pro 12.9-inch (2nd generation) or later

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