A new technique for enhancing underwater images using entropy curves and local contrast enhancement
Priyanshu Singh Yadav, Bhupendra Gupta, Subir Singh Lamba · International Journal of Remote Sensing · 2025
In the field of underwater imaging, the prevalent challenges of light scattering and absorption have long impact on the quality and utility of captured images. To effectively solve these quality degradations, a novel enhancement technique using entropy curves and local contrast enhancement technique has been discussed in this study. Initially, an attenuation-map-guided colour correction strategy is employed to correct colour distortions. Subsequently, detail enhancement is achieved through the entropy curve equalization method and by application of contrast limited adaptive histogram equalization (CLAHE), local contrast enhancement is achieved. To obtain a high-quality underwater image, the processed image is further improved using a weighted wavelet visual perception fusion strategy. A comprehensive visual and numerical evaluation confirms the superiority of the proposed method over existing contrast enhancement techniques, enabling the generation of detailed, noise-free, and contrast-enhanced underwater images, which help in more effective underwater exploration and analysis.