Matlab - https://www.mathworks.com/help/images/enhance-color-separati...

This paper might also be of interest - https://www.mdpi.com/2227-7390/13/20/3297

"In this paper, we review the theory behind decorrelation stretch and propose some alternative algorithms that resolve the issues of the standard approach."

The app is called DStretch, it's available for iOS and Android

https://dstretch.com/Apps/index.html

Had an llm build something quickly so I could play with it. https://shannietron.github.io/decorrelation_stretch/

"A contribution is mandatory before I will send the plugin. It may take me a few days to respond, have patience. Please note that the plugin is not an app. It has much more functionality than is possible in an app on a smartphone."

"The DStretch [mobile] app is a lightweight version of DStretch intended to give users the ability to enhance rock art in the field. It is not a substitute for the DStretch plugin which has much more functionality."