In spectral color reproduction, there is typically a mismatch between the spectral gamut of the source device and that of the destination device. The adjustment for this gamut mismatch is referred to as spectral gamut mapping.
In this regard, it is typically noted that 31 dimensions are sufficient to represent the spectral reflectance of a physical stimuli, which gives rise to a particular color sensation under a given illuminant and viewing condition. The 31 dimensions correspond to the visible wavelengths from 400 nm to 700 nm, at every 10 nm interval.
However, spectral gamut mapping using 31 dimensions may be too demanding for some computing hardware, such as general purpose computers or specialized ASIC devices. As such, an interim connection space (ICS) may be used for spectral gamut mapping. An ICS is an intermediate space which can be used to reduce the number of dimensions associated with spectral gamut mapping. In principle, an ICS has any dimension lower than 31. Typically, an ICS has a dimension ranging from 5 to 8.
In designing an ICS, the ICS should be accurate enough such that its relatively low dimension can still carry the information needed for spectral color imaging. In other words, the ICS should work for many illuminants, not just one or two. On the other hand, since many operations are typically associated with spectral gamut mapping (e.g., convex hulling), and these operations involve or generate results of complexity that may depend exponentially on the dimension, there is a desire to keep the dimension as low as possible.
Thus, there is a need for improved efficiency in spectral gamut mapping using an ICS, so that accuracy is maintain and the number of dimensions is reduced.