Colour vision deficiency correction in image processing

Abstract

In the Human eye there are two types of image receptor cells cones and rods. Rods are helpful for seeing the image in low light or in the dark whereas the cones work for seeing the image in different colours. Both the receptors cells are found in retina of human eye. They contain three colour pigments Red (Large Bandwidth), Green (Medium Bandwidth) and Blue (Small Bandwidth) by which we are trichromats (tri =3 chromats =colour) and able to see any object in the world because of all objects are viewable by these colour hues. Mostly the colour blindness is the genetic mutation and not to be cured. It can also get place when there is a problem related to pigments in certain nerve cells (cone) of the eye or when there would be a trauma in mind or the chemical accident by which those receptor cells got affect. In the Human vision there are different stages which describe what type of colour vision deficiency the people have. Monochromacy (1%): Total colour blinded Dichromacy (10%): Partial colour blinded (i) red-green colour blindness (ii) blue-yellow colour blindness. Trichromacy: Normal colour vision. The Dichromacy, this type of colour blindness mostly people have. So correcting it, a new filter is developed in the image processing on the basis of Ishihara colour test. It works successfully as per tested it many time. In this filter adjusting, contrast stretching and inverting function are used for providing better result and it does. By applying this new filter the normal and as well colour vision deficient people easily recognise the objects whether they are of any of shape, number or alphabets.