A new focus measure for fusion of multi-focus noisy images

Images usually are corrupted by noise produced by image sensors in many practical applications. Image noise may cause miscalculation of image definition because the traditional focus measures can´t give a correct evaluation of image clarity in the presence of noise, which introduces significant errors in the results of image fusion. A new measure based on lifting wavelet transform was proposed for the existence of image noise by the energy of high-frequency and low-frequency subbands after the second-level decomposition. Experimental results show that the new measure presented in this paper can provide better performance than other focus measures for noisy images.