Noisy perceptual derivatives

[apcamargo]

I'm playing around with viscm and I noticed that all colormaps that I create end up with very noisy perceptual derivatives:

test_cm.jscm.txt

This is not a problem with the built-in colormaps, so I assume it is not a problem with the viewer, but with the colormap creation process. Any clue of what might be going on here?

[apcamargo]

Apparently, this doesn't happen when I load the colormap from a .py file:

[mfisher87]

Looks related to: #56

I don't have a great idea why this is happening. I may have time to dig in to it soon, but not guaranteed.

[dnadlinger]

I believe the proximate cause for this is the 8-bit quantisation in the saved .jscm data, whereas the built-in ones are saved as floats to 6 decimal digits. Since the output will usually go straight into 8-bit-per-channel colour data, this doesn't appear to be an issue per se.