Modified Background Correction Algorithms for Pavement Images

Abstract:

Pavement images through charge coupled device (CCD) cameras always go with nonuniform background illumination,therefore,the paper presents an improved typical methods for background correction,including modified Cheng’s method and two modified average background methods,background subtraction and correction coefficient method.The methods mentioned are applied to real pavement distress images and the results show that modified Cheng’s method has advantage in simplified calculation and can be applied to any pavement image.Moreover,background subtraction has stronger ability to eliminate background noise compared to the correction coefficient method,but images corrected by correction coefficient method are more suitable to the observation of human eye.Besides,the result of segmentation after background correction shows that Ostu method can provide good segmented images when the background is uniform in pavement images.

Key words:pavement distress; background correction; image processing; image enhancement