Equalize Histogram / Levels

I'm trying to implement the following with opencv4nodejs, but I couldn't get numjs to install and don't see another way to satisfy the numpy requirement in nodejs (have little experience there too though). Suggestions?

https://docs.opencv.org/3.2.0/d5/daf/tutorial_py_histogram_equalization.html

The issue names no source file or test. Start with the linked OpenCV histogram-equalization tutorial and inspect existing opencv4nodejs image-processing entry points to determine how the requested operation could work without numjs or numpy; done should be a clear, project-compatible path for histogram equalization or levels.

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