Research into Methods for Determining Colour Differences in the CIELAB Uniform Colour Space
A problem of qualitative determination of the results of colour image capturing by digital devices based on uniform colour systems arises during analysis of colour images. The article describes methods of determining colour difference as recommended by CIE for the CIELAB system, presents mathematical formulation of the system and its modifications, describes the programme developed for calculating colour difference for each described method, and describes testing of this programme using 14 sample colours from the Munsell Book of Colour. Three groups of red, green and blue filters with 7 filters in each were selected as the study object. The filters were selected based on possibility of their further application for determining colour shift by digital devices. Filter colour difference was studied in the groups with different standard sources of light and using three methods of calculation of this difference. Analysis of the obtained results is presented and conclusions are made on possibility to apply each method in different industrial spheres. The article may be useful for colour analysis specialists, quality inspectors and specialists in digital devices and computer vision.