Real Color Image Enhanced by Illumination - Reflectance Model and Wavelet Transformation

Because the greatly most algorithms of real color image enhancement did not relate to the spectral sensitivity of most human vision, the color restoration functions of some real color image enhancement algorithms are greatly at random and not proved , and the real color images enhanced which are based on illumination-reflectance model have the loss of details and the dasiahalospsila, we proposed a new algorithm to overcome these disadvantages. Firstly, we transform the real color image from RGB space to HSV space which is approximately orthonormal system between color and value. Secondly, the illumination and the reflectance of value are separated by homomorphic decomposition based on illumination-reflectance model. We have discovered that the high dynamic range of image including high bright lights is mainly caused by the reflectance. Thirdly, the details of reflectance are preserved by wavelet transform. Fourthly, the dynamic range of reflectance is compressed by Butterworth filtering. Lastly, the energy of the saturation of real color image in HSV space is attenuated according to the spectral sensitivity of most human vision. Experiments show that the color of image enhanced adapts well to the most people vision and is not obviously distorted, the preservation of the details is perfectly and the dasiahalospsila is effectively restrained. Real color images enhanced by the algorithm are much better than the multi-scales Retinexpsilas with color restoration (MSRCR).