Hue preserving‐based approach for underwater colour image enhancement

Abstract

In this study, a novel underwater colour image enhancement approach based on hue preserving is presented by combining hue–saturation–intensity (HSI) and HS–value (HSV) colour models. In this study, the proposed wavelet‐domain filtering (WDF) and constrained histogram stretching (CHS) algorithms are operated on HSI and HSV colour models, respectively. The degraded image is first converted from red–green–blue colour model into the HSI colour model, wherein the hue component H is preserved and WDF algorithm is executed on the S and I components. Similarly, the image is further converted into the HSV colour model, wherein H component is kept invariant as well and CHS algorithm is applied on the S and V components. The authors' key contribution is that the H preserving method can improve image quality in terms of contrast, colour rendition, non‐uniform illumination, and denoising. In addition, experimental results show that the proposed approach outperforms several other state‐of‐the‐art algorithms.