A hybrid DWT-DCLAHE method for enhancement of low contrast underwater images
Ankit Chaubey, Anshul Atre · 2017 International conference of Electronics, Communication and Aerospace Technology (ICECA) · 2017
In this research, presented an underwater image enhancement (IE) making use of discrete wavelet ransform (DWT) with dynamic contrast limited adaptive histogram equalization (DCLAHE) algorithm. The principle issue in IE underwater pictures is that non-uniform illumination, low-brighntness, blur impact in view of turbulence in the stream of water. In underwater images, it impacts the diffusing of light from a few particles of various sizes, low intensity in light of low perceivability conditions, suspended movement particles. In this approach, firstly take RGB image and apply DWT on LL band of input image. After that convert RGB to YCBCR format for further processing. Perform DCLAHE method on luminance part of LL band image and chrominance channel remain unvhanged. After this process, convert YCBCR to RGB format. Finally, merge all the modified bands using inverse DWT. The new result is applied on peak signal Noise Ratio (PSNR), Entropy and time execution. This algorithm is compared with three algorithms, namely DCP[1], brightness bi histogram equalization (BBHE), Contrast Enhance method. The proposed algorithm shows that better performance as compared to other algorithms.