The International Standards Organization (ISO/IEC JTC1/SC2/WG10) has prepared an International Standard, [ISO/IEC 15444-15] (JPEG 2000 Part 15 HTJ2K), for the digital compression and coding of continuous-tone still images. This standard is known as the JPEG 2000 Part 15 HTJ2K Standard, or just the HTJ2K standard.

The JPEG 2000 Part 15 HTJ2K Standard sets out requirements and implementation guidelines for the coded representation of compressed image data to be interchanged between applications. The processes and representations are intended to be generic in order to support the broad range of applications for color and grayscale still images for the purpose of communications and storage within computer systems.

Though a different coding process from those specified in ISO 10918-1 is used, the syntax of the encoded bit stream is closely related.

An HTJ2K stream allows for bit depths up to 38 bits per channel.

Inclusion of an HTJ2K coded image in a DICOM message is facilitated by the use of specific Transfer Syntaxes that are defined in Annex A.