ITU-T Recommendation T.809 | ISO/IEC 15444-10 is a work item subdivision of ISO/IEC 15444 that provides extensions of ITU‑T Recommendation T.800 | ISO/IEC 15444-1 and ITU-T Recommendation T.801 | ISO/IEC 15444-2 for logically cuboidal data sets. In particular, it respects all existing capabilities and syntax of ITU‑T Recommendation T.800 | ISO/IEC 15444-1 and part of the existing capabilities of ITU-T Recommendation T.801 | ISO/IEC 15444-2 for multi-component images, while providing alternatives and extensions to some of those capabilities. Within these constraints, it provides an isotropic specification for three-dimensional data sets; i.e., the project provides identical processing capabilities in all three dimensions even though ITU‑T Recommendation T.800 | ISO/IEC 15444-1 and ITU-T Recommendation T.801 | ISO/IEC 15444-2 codestream syntax differentiates between the two spatial axes and the cross-component axis. The context models currently used in this Recommendation | International Standard are as in ITU-T Recommendation T.800 | ISO/IEC 15444-1 and ITU-T Recommendation T.801 | ISO/IEC 15444-2. Improved context models will be introduced through an amendment.
Corrigendum 1 (2011/05, integrated in this new edition) corrects a number of minor mistakes that were present in various formulas of Annex B. It also provides a more formal and unambiguous description on the mandatory use of the CAP marker segment in the codestream, in order to enhance interoperability with the other parts of the JPEG 2000 standard. Furthermore, it introduced new Annex E on how quantization should be handled for JP3D images.