The Hap Image format allows for the storage of a still image using the Hap codec. Hap stores images in a format that can be decoded in part by dedicated graphics hardware on modern computer systems. It is well suited to the display of very high resolution images when fast decoding is a priority.
For more information about the Hap codec, visit the Hap repo at https://github.com/Vidvox/hap.
This repository hosts a specification document and reference source code for developers.