Image calibration for color comparison

The aim is to measure the color difference between two images of the same object taken before and after a treatment that resulted in color change (such as teeth bleaching i.e. teeth treatment with different whitening products). Image calibration is a necessary component for the comparison of colors between the objects contained in the images. The two aspects of the image calibration process will be presented in this paper: position calibration of objects (studied to ensure that the comparison is performed between the same area of the objects) and color calibration (altered from the acquisition of images).