A weak-illumation image enhancement method uisng homomorphic filter and image fusion

摘要

In this paper, an image enhancement method for weak-illumination image is studied by using homomorphic filter and image fusion. First, the discrete-cosine-transform (DCT) based homomorphic filtering technique is used to enhance image without changing hue and saturation. Because it is not easy to determine suitable filter parameters such that image quality is good for all objects, an image fusion method is then developed to combine several enhanced images with different exposures to get the final result. Finally, a back-lighting image is used to show the effectiveness of the proposed method and the comparisons with traditional methods are made.