Performance of brightness enhancement technique for narrow-band and white-band images

Abstract

Image enhancement technique plays a vital role in image analysis. White-band images (WBI) and narrow band images (NBI) are the two types of images that are widely used in capsule endoscopy. It is a general practice to compress the images and process them at the chip level embedded in the capsule in order to minimize the power consumption. In the due course, it is often required to enhance the features of the image so that, most favorable information from the images can be extracted. Loss of naturalness in the image while processing for image enhancement is observed. In this paper, a technique called brightness enhancement followed by color restoration is suggested for images with non-linear illumination. The technique employs a bright pass filter which acts on reflectance and luminance forms of image obtained after decomposing of the original image. The simulation experiment is carried on both white-band images and narrow-band images.