I ran into this problem while trying to find the paint color of the doors in my house: is it in principe possible to automatically determine the paint color from a photo?
Different types of colour standards (such as RAL, https://en.wikipedia.org/wiki/List_of_RAL_colors) mention RGB values, but of course lighting conditions, material, camera and probably other factors highly affect the RGB value that is measured.
Does a solution to this problem already exist?
An idea I had is to hold an official color reference chart in the photo next to the target object (e.g. my door), so the transformation due to lighting conditions and camera between the known RGB values of the colors on the reference chart and those in the photo could somehow be established. Then the inverse transformation could be applied to the color of the target object and the closest matching paint color could be found.
Could this idea work and if so, what kind of transformation between reference and measurement could be expected?