“…Following are the different methods used for pre-processing. Self dual multi-scale morphological toggle (SMTT) block ( Belekar & Chougule, 2015 ), wiener filter ( Patel & Mishra, 2015 ), median filtering ( Elsalamony, 2016 ; Bhanushali et al, 2016 ; Mohite Patil & Bhagavan, 2016 ; ANP and Wildlife Service, 1986 ; Thiruvinal & Ram, 2017 ), Gaussian filtering ( Yildirim & Çinar, 2019 ), gray-scale transformation ( Patel & Mishra, 2015 ; Elsalamony, 2016 ; Bhanushali et al, 2016 ; Mohite Patil & Bhagavan, 2016 ; ANP and Wildlife Service, 1986 ; Bhagavathi & Thomas Niba, 2016 ; Biswas & Ghoshal, 2016 ; Thiruvinal & Ram, 2017 ) which has 3 types viz Linear, Logarithmic and Power–law, histogram stretching ( Elsalamony, 2016 ; Bhanushali et al, 2016 ; Mohite Patil & Bhagavan, 2016 ; ANP and Wildlife Service, 1986 ), green color component from the RGB image ( Negm, Hassan & Kandil, 2018 ), morphological operations ( Elsalamony, 2016 ), edge detection ( Biswas & Ghoshal, 2016 ).…”