Study and analysis of various image fusion methods by DWT and MSR

An image fusion method, based on Multi-scale Retinex (MSR) and modified Daubechies architecture for discrete wavelet transform (DWT) is proposed. MSR is used for enhancement of shadowed detail. The good color rendition and more details in shadows derived from the source image and the enhanced image can be combined into a fused image by DWT. The proposed DWT is composed of two independent FIR filters: high-pass transposed form FIR filters. Each FIR filter is a two stage pipeline whose clock cycle is only either two adders delay or one multiplier delay. The area can be optimized by RAG (Reduced Adder Graph) algorithm. This daubechies architecture achieves faster speed, shorter output latency. The result of fused image is evaluated by entropy and human perception and it showed that fuse image has the maximum value of entropy and is more accord with human visual system.