JPEG XT is similar in concept to JPEG-HDR. Its precise relationship to JPEG-HDR is not clear; the formats do not appear to be compatible.
All the critical parts of the standard were published as of 2016-10-15.
A JPEG XT file contains one or more APP11 segments (see JPEG#Application segments) whose data begins with ASCII "
JP". Note that the signature is just these two bytes, and has no NUL terminator.
The documents listed here are not necessarily available yet, and if they are, they're probably not free to download.
- ISO/IEC 18477-1:2015 - Part 1: Scalable compression and coding of continuous-tone still images
- ISO/IEC 18477-2:2016 - Part 2: Extensions for high dynamic range images
- ISO/IEC 18477-3:2015 - Part 3: Box file format
- ISO/IEC 18477-4:2017 - Part 4: Conformance testing
- ISO/IEC 18477-5 - Part 5: Reference software
- ISO/IEC 18477-6:2016 - Part 6: IDR Integer Coding
- ISO/IEC 18477-7:2016 - Part 7: HDR Floating-Point Coding
- ISO/IEC 18477-8:2016 - Part 8: Lossless and Near-lossless Coding
- ISO/IEC 18477-9:2016 - Part 9: Alpha Channel Coding