Image preprocessing

An image Z with M rows and N columns and its intensity level range is measured as a collection of fuzzy singletons. The intensity range is in between L, 0 to 1. The membership value μ_ik with color intensity x_n x_m is considered. The contrast intensification operator was introduced by Zadeh in 1973. This operator is fully dependent on the membership function and applied for enhancement proposes. The constant operator is selected from image entropy value (e). So,InT=∑v=0L−1[μik’−e]2.J(k)(3.1)∑v=0L−1J(k)=1(3.2)

where, J(k) represents the frequency of intensity values. The spatial plane is changed by applying the intensification operators. Before these existing methods were proposed, various authors suggested filtering operations such as median, wiener and mode and then contrast level improvement was done through point operations. In previous works, e value was calculated through constant value 0.5. The “index of fuzziness” increases and decreases based upon the image contrast.