How to change efficiently Colormap of big .fig files in Matlab?

I have some 2 GB .fig files where I would like to change colormaps smartly. The initial colormap is colormap(1-gray(1024)); made initially for computers. I would like to change smoothly to Parula etc for visualization purposes. There is a need for changing to many different colormaps efficiently. It may be the case that the original gray is not the optimum for the starting point.

My main interest is the time-series analysis with Mathematica where I need to find some colormap which I can use with meshgrid data structure. There are some colormaps presented in the book Passive Acoustic Monitoring of Cetaceans by Walter M.X. Zimmer which seem to be relevant here. Some alternatives to be considered

1. colormap(1-gray(1024))
2. colormap(1-gray(12))
3. colormap(1-gray)
4. colormap(cmap)
5. colormap(1-gray(7*2))
6. colormap(1-gray(8*2))

The situation is that changing from one colormap to another is too slow with big .fig files. Little (or no?) history is taken into account when changing the colormap, I think. The previous change of a colormap does not decrease the execution time of the next colormap; although you would change subsequently back to the initial colormap. The biggest problem is with colormaps that are not injective with each other. Questions

• Why do they take everything except clauses (1-gray)?
• How can you change smoothly colormap of big .fig files in Matlab? There are similarities between some colormaps. Sometimes, the default way etc colormap(parula(200)) is too slow. I would like to speed up things if similarities between colormaps could be used; by configuring the initial colormap suitable for some changes of colormaps.
• How can you decide a colormap such that it is usable for the time-series analysis in Mathematica? Just an example, please.

Use Mathematica 11 instead, since its default colormap has much better contrast and its viewer fits much better for your dynamic target.