18 International Journal of Recent Research and Review, Vol.VI, June 2013 ISSN 2277 – 8322 Review of Color Blindness Removal Methods using Image Processing Ruchi Kulshrestha 1 , R.K. Bairwa 2 Student, Department of Computer Science & Engineering, KITE, Jaipur, India Assistant Professor, Department of Computer Science & Engineering, KITE, Jaipur, India E-mail: ruchi_kulshrestha23@yahoo.com Abstract- Color blindness is deficiency of color vision. Due to presence of color blindness, human eye becomes unable to differentiate colors with each other. Generally reason behind color blindness is genetic but sometimes it happens due to some damage and disorder in brain and eye. Color blindness is of many types like Red-Green, Blue-Yellow etc. Red-Green color blindness is most common type of deficiency in which person is unable to differentiate between red and green colors. Index Terms- Color blindness, Image processing, color vision, red-green color deficiency, Ishihara color test, RGB, HSV. I. INTRODUCTION Color blindness is a color vision problem where person is deficient to recognize colors like red, green and blue. To see something there are photoreceptors on retina of human eye, which pass information of light to the brain [1]. There are two types of photoreceptors: Rods and cones. Cones are responsible for color vision while rods are not sensitive to colors. There are three types of cones: (i) S cones: Sensitive to short wavelength (Blue color). (ii) M cones: Sensitive to medium wavelength (Green color). (iii) L cones: Sensitive to long wavelength (Red color). Due to abnormality of these cones there are three types of color blindness: (i) Monochromacy: When a person has a single cone cell or no cone cells. This color blindness type is called total color blindness. It is very rare. (ii) Dichromacy: When one of the three cone cells is missing. (iii) Anomalous Trichromacy: When all three types of cones present but with shifted peaks of sensitivity for one of them. Dichromacy and anomalous Trichromacy are of further three types: (a) Protanopia: Due to absence or improper functioning of L-Cones. (b) Deuteranopia: Due to absence or improper functioning of M-Cones. (c) Tritanopia: Due to absence or improper functioning of S-Cones. Fig. 1. Effect of Color Blindness