heif, but they may use a different extension to indicate the specific codec used. Generic HEIF image files are typically stored with filename extensions. heifs for sequences, which can both be used with any codec. Variants Īs HEIF is a container format, it can contain still images and image sequences that are coded in different formats. Image metadata Storage of EXIF, XMP and similar metadata which accompany the images stored in the HEIF file. These data are not displayed as such, but used in various forms to complement another image item. Auxiliary image items Storage of image data, such as an alpha plane or a depth map, which complements another image item. Hence, file sizes can be drastically reduced when many images are stored in the same HEIF file. Different prediction options can be used in order to exploit the temporal and spatial similarities between the images. Image sequences Storage of multiple time-related and/or temporally predicted images (like a burst-photo shot or cinemagraph animation), their properties and thumbnails. The storage overhead of derived images is small. These instructions (rectangular cropping, rotation by one, two or three quarter-turns, timed graphic overlays, etc.) and images are stored separately in the HEIF file, and describe specific transformations to be applied to the input images.
Image derivations Derived images enable non-destructive image editing, and are created on the fly by the rendering software using editing instructions stored separately in the HEIF file.
HEIF files can store the following types of data: Image items Storage of individual images, image properties and thumbnails. On some systems, pictures stored in the HEIC format are converted automatically to the older JPEG format when they are sent outside of the system. Īpple was the first major adopter of the format in 2017 with the introduction of iOS 11 using HEIC variant.
The technical development of the specification took about one and a half years and was finalized in the middle of 2015. The requirements and main use cases of HEIF were defined in 2013.
HEIF files are a special case of the ISO Base Media File Format ( ISOBMFF, ISO/IEC 14496-12), first defined in 2001 as a shared part of MP4 and JPEG 2000. Such files require less storage space than the equivalent quality JPEG. HEIF files containing HEVC-encoded images are also known as HEIC files. HEVC is an image and video encoding format and the default image codec used with HEIF. HEIF can store images encoded with multiple coding formats, for example both SDR and HDR images. The standard covers multimedia files that can also include other media streams, such as timed text, audio and video. High Efficiency Image File Format ( HEIF) is a container format for storing individual digital images and image sequences. Image/heif, image/heif-sequence image/heic, image/heic-sequence image/avif, image/avif-sequence