Oiiotool for calculating the proposed error metric

In the CLF VWG we have discussed the need for an easy-to-use tool that CLF implementors could use to measure the error on output from their software or hardware, relative to some reference image that has undergone processing of the same CLF file(s). The proposed error metric is:

abs(actual - aim) / max(abs(aim), 0.01)

where ‘actual’ is the processed output image from the CLF implementor’s software or hardware, and ‘aim’ is the image as output from a reference or example CLF implementation (e.g. OpenColorIO tools).

I think we can use oiiotool (from OpenImageIO) to calculate the results of the error metric. TBD are thresholds for max error and mean error, but believe that oiiotool will be able to handle those bits as well.

Here’s the Linux oiiotool command and args to generate an error metric image:

$ oiiotool <aim-image> <actual-image> --absdiff <aim-image> --abs --maxc 0.01 --div -o out.exr

Please give it a try if you can, and let me know what you think!