Decoding HEIF, the image format that cuts photo sizes in half

If you have ever taken a photo with your smartphone, you might have noticed that the file size can vary depending on the quality, resolution, and compression of the image. A typical JPEG image, for example, can take up several megabytes of storage space, which can quickly add up if you have hundreds or thousands of photos on your device.

But what if there was a way to reduce the file size of your photos without compromising the quality or resolution? That is the promise of HEIF, a new image format that stands for High Efficiency Image File Format. 

HEIF is an image container that can store multiple images, such as bursts, live photos, or HDR photos, in a single file. It can also store metadata, such as location, date, time, and camera settings, as well as image editing information, (such as cropping, rotation, and filters.)

HEIF is based on the HEVC (High Efficiency Video Coding) standard, which is also known as H.265. HEVC is a video compression technology that can deliver high-quality video at half the bitrate of the previous standard, H.264. HEIF applies the same compression techniques to still images, resulting in files that are up to 50% smaller than JPEG while preserving the same or better quality.

How does HEIF work?

HEIF uses a technique called predictive coding to compress images. Predictive coding works by analyzing the pixels in an image and finding patterns and similarities among them. For example, if an image has a large area of blue sky, the encoder can predict that the pixels in that area will have similar values of colour and brightness, and encode them with fewer bits. The encoder can also use information from previous or neighbouring images to predict the pixels in the current image and encode only the differences. This reduces the amount of data that needs to be stored and transmitted while maintaining the quality of the image.

HEIF also supports lossless compression, which means that the original image can be reconstructed exactly from the compressed data. Lossless compression is useful for images that contain a lot of detail, such as text, logos, or graphics, where any loss of quality would be noticeable. HEIF can achieve lossless compression by using a different technique called entropy coding, which works by assigning shorter codes to more frequent symbols and longer codes to less frequent symbols. For example, if an image has more white pixels than black pixels, the encoder can assign a shorter code to white and a longer code to black, and save bits in the process.

What are the benefits of HEIF?

HEIF offers several benefits over other image formats, such as JPEG, PNG, or GIF. Some of the main benefits are:

• Smaller file size: HEIF can reduce the file size of images by up to 50%, compared to JPEG, without sacrificing quality. This means that you can store more photos on your device, or upload and download them faster over the internet. Smaller file size also means lower bandwidth consumption and lower storage costs, which can benefit both users and service providers.

• Higher quality: HEIF can preserve more details and colours in images, especially in high dynamic range (HDR) scenarios, where there are large differences between the brightest and darkest areas of the image. HEIF can also support higher resolutions, up to 16K, and higher bit depths, up to 16 bits per channel, which can enhance the clarity and richness of the image.

• More features: HEIF can store multiple images in a single file, which can enable new functionalities, such as bursts, live photos, or HDR photos. HEIF can also store metadata, such as location, date, time, and camera settings, as well as image editing information, such as cropping, rotation, and filters. This can allow users to edit and share their photos more easily and flexibly, without losing the original data.

• More compatibility: HEIF is based on a widely adopted standard, HEVC, supported by many devices and platforms, such as smartphones, tablets, computers, TVs, and streaming services. HEIF can also be converted to other formats, such as JPEG or PNG, if needed, without losing much quality. HEIF can also interoperate with other image formats, such as JPEG 2000 or AVIF, which are based on similar technologies.

How to use HEIF?

HEIF is already supported by some of the most popular devices and platforms, such as iOS, macOS, Windows 10, Android, and Google Photos. If you have one of these devices or platforms, you can start using HEIF by changing the settings of your camera or photo app. For example, on iOS, you can go to Settings > Camera > Formats, and choose High Efficiency to enable HEIF. On Windows 10, you can go to Settings > System > Storage, and choose HEIF Image Extensions to enable HEIF.

If you want to view or edit HEIF images on other devices or platforms, you should install a software or plugin that can decode HEIF. For example, you can use the HEIF Image Viewer the HEIF Image Extension on Windows 10, or the HEIF Reader or the HEIF Writer on macOS. You can also use online tools, such as heictojpg.com or heic2jpg.com, to convert HEIF images to JPEG or other formats.

Conclusion

HEIF is a new image format that can cut the file size of photos in half while maintaining or improving the quality. HEIF can also store multiple images, metadata, and image editing information in a single file, which can enable new features and functionalities. HEIF is based on a widely adopted standard, HEVC, supported by many devices and platforms. HEIF can also be converted to other formats, if needed, without losing much quality. HEIF is a promising technology that can revolutionize how we capture, store, and share our photos.