thresholdRecolor: Drop minor colors from a recolorize object

In recolorize: Color-Based Image Segmentation

Drop minor colors from a recolorize object

Description

Drops color patches whose cumulative sum (as a proportion of total pixels assigned) is equal to or less than pct, so that only the dominant color patches remain, and refits the object with the reduced set of color centers Useful for dropping spurious detail colors.

Usage

thresholdRecolor(recolorize_obj, pct = 0.05, plotting = TRUE, ...)

Arguments

recolorize_obj	An object of class recolorize.
pct	The proportion cutoff (0-1) for dropping color patches. The higher this value is, the more/larger color centers will be dropped.
plotting	Logical. Plot the results?
...	Further arguments passed to imposeColors, which is called for refitting a new recolorize object for the reduced set of clusters.

Details

This function is fairly simple in execution: the color centers are arranged by their sizes, largest to smallest, and their cumulative sum is calculated. The minimum number of color centers to reach a cumulative sum equal to or greater than the cutoff (1 - pct) is retained, and these dominant colors are used to re-fit the image. Despite being straightforward, this can be a surprisingly useful function.

Value

A recolorize object.

Examples

img <- system.file("extdata/fulgidissima.png", package = "recolorize")
init_fit <- recolorize(img, bins = 3)
thresh_fit <- thresholdRecolor(init_fit, pct = 0.1)

# if you take it too far, you just get one color back:
thresh_fit_oops <- thresholdRecolor(init_fit, pct = 1)

recolorize documentation built on April 4, 2025, 3:07 a.m.