A graphical user interface (GUI) to check an existing jpg/png image for (possible) color constraints. The image will be converted to protanope vision, deuteranope vision, and a desaturated version (monochromatic vision). Allows a rapid check whether the colors used in the image show some constraints with respect to color deficiency or color blindness.

cvd_emulator(file, overwrite = FALSE, shiny.trace = FALSE)



If not set, an interactive GUI will be started. If x is of type character it has to be the full path to an image of type png or jpg/jpeg. The image will be converted and stored on disc, no GUI.


logical. Only used if file is provided. Allow the function to overwrite files on disc if they exist.


logical. Can be set to TRUE for more verbose output when the GUI is started (development flag).


Zeileis A, Fisher JC, Hornik K, Ihaka R, McWhite CD, Murrell P, Stauffer R, Wilke CO (2020). “ccolorspace: A Toolbox for Manipulating and Assessing Colors and Palettes.” Journal of Statistical Software, 96(1), 1--49. doi: 10.18637/jss.v096.i01


Reto Stauffer, Claus O. Wilke, Achim Zeileis