Trying to compute CRI from a spectra

[Steve]

I am trying to figure out the algorithm to compute the color rendering index
from a spectrum (spaced 5nm intervals). I have the CIE 13.3-1995 publication,
but it is not clear what one is to do. I can compute X,Y,Z from the spectrum,
along with the X,Y,Z from the test samples (using Table 1 and Table 2 in the
publication), but I don't understand the notation that is used in Equations 5-3
through 5-6.

The publication comes with a CD with the CRI calculation program CIE13_3D.EXE.
If anyone knows where I could obtain the source code to the program, it would
answer most of my questions.

Any help would be greatly appreciated.

Thanks in advance.

Steve

[Ingo Thies]

Hi Steve,

although I didn't make the full CRI calculations yet (only things like
color space conversion, color temperature computation etc.), I am
planning to do so (when time permits...). Then, I could provide a
detailed "cookbook" for this. Maybe this Wikipedia article is helpful:

http://en.wikipedia.org/wiki/Color_rendering_index

In particular see the section "Test method" which describes the
essential steps.

However, I would also be interested in an open source project about CRI
computation.

Best wishes,




Ingo