Abstract

Image plays an important role in serval application in our day-to-day actives. One of the key concepts in processing of digital image is image enhancement. The enhancement of image helps in identifying the target object. The features present in the image need to be enhanced for obtaining high visual quality. To realize image enhancement different type of techniques are involved and presented in this paper. Images taken in low-light situations frequently exhibit characteristics like lower level of brightness, inadequate contrast, a limited grayscale, colour deformations, and significant disruption, all of which have a negative impact on the quality of the visual effects on human eyes and severely limit the effectiveness of many automated vision frameworks. The effect of lower contrast images is clearly observed in underwater images, CC footage images, satellite images, areal images, medical images etc. The work presented covers the existing enhancement techniques, availability of datasets for performing the techniques, finally the assessment metrics involved in describing the enhancement quality of image are discussed.