Efficient Underwater color image enhancement using CLAHE method
Abstract Conventional contrast enhancement techniques often fail to produce satisfactory results for low-contrast images, and cannot be automatically applied to different images because processing parameters must be specified manually to produce satisfactory results for a given image. This paper proposes a contrast enchancement technique to enhance colour images captured under poor illumination and varying environmental conditions. Images are converted from RGB to HSV colour space where enhancement is achieved and reconverted to the RGB. Efficient Underwater color image enhancement using CLAHE method. Class Limited Adaptive Histogram Equalization (CLAHE) is used to enhance the luminance component (V). Discrete Wavelet Transform is applied to the Saturation (S) components, and the decomposed approximation coefficients are modified by a mapping function derived from scaling triangle transform. The enhanced S component is obtained through Inverse Wavelet transforms. The image is then converted back to the RGB colour space. Objective parameters (Peak-signal-to-noise ratio (PSNR) is used for performance evaluation. The algorithm implemented in MATLAB was tested images.