In order to check the perception of color choices, I'd like to be able to simulate color blindness for people with normal eyesight (me, basically). My goal is to weaken / worsen / decrease the contrast in order to get a feeling how bad something (an advertisement, UI design etc.) is for a person with color vision deficiencies. It should consider typical color blindness types that are medically accepted, like red-green blindness, blue weakness, blue blindness and monochromacy. It's basically the opposite of what is requested in [Screen filter for colorblind](https://softwarerecs.stackexchange.com/questions/19781/screen-filter-for-colorblind), where the goal is to improve the contrast for colorblind people. Please suggest a gratis offline tool for Windows. I do not need: - a pure contrast analyzer like [CCA](https://www.tpgi.com/color-contrast-checker/)