ISO/IEC 15444-2:2021

This document defines a set of lossless (bit-preserving) and lossy compression methods for coding continuous-tone, bi-level, grey-scale, colour digital still images, or multi-component images.
This document:
–      specifies extended decoding processes for converting compressed image data to reconstructed image data;
–      specifies an extended codestream syntax containing information for interpreting the compressed image data;
–      specifies an extended file format;
–      specifies a container to store image metadata;
–      defines a standard set of image metadata;
–      provides guidance on extended encoding processes for converting source image data to compressed image data;
–      provides guidance on how to implement these processes in practice.