Amendment 6 to ITU-T T.800 (2002) | ISO/IEC 15444-1 (2004) clarifies the usage of ICC profiles to indicate colour spaces within the framework of ITU-T T.800 (2002) | ISO/IEC 15444-1 (2004). Specifically, it clarifies that matrix based display and matrix based input profiles are applicable.

It was furthermore found that the definitions for the tone mapping operations for grey scale and sRGB colour spaces of the colour specification box were only applicable for 8bpp input data, and hence did not allow the required bit-depth scalability JPEG 2000 follows otherwise. The definitions were extended to arbitrary bit depths, following the same principles as in ITU-T T.801 (2002) | ISO/IEC 15444-2 (2004) while restricting them to simple cases.

Amendment 6 also improves and clarifies the definition of the Capture Resolution and Default Display Resolution boxes, and adds informative notes on their suggested usage.