Comparison of global methods for the image contrast enhancement based on biometric images

This work presents the methods of improvement of biometric images contrast, and it corresponds to one of the main parts of the biometric system that verify identities based on distribution of the blood vessels in a hand. The acquisition of the palm blood vessel pattern causes noises that can prevent the right verification. To solve this problem, we investigate four different methods of contrast enhancement, and provide an evaluation of their performance by using four different quantitative contrast measurement methods.