Study The Effect of Lightness on The Good Vision of Written text in the class room

Abstract

The range of brightness and contrast is one of the light characteristics that plays a major role in the resolution of optical vision. Brightness property discriminate between high light or darkness of written text on the whiteboard. The black color has a low brightness and the white color has a high contrast. However, contrast property represents the rate between lighting the symbol (The text) and the background (The Whiteboard). If there is a consistency in the light intensity distribution of classroom (uniform lighting), the contrast values of written text on the whiteboard is affected by the distance between camera and whiteboard. In case of far distances, contrast values will decrease due to the blur appearing around the text by increasing the distance between camera and whiteboard.Hence, we aimed, in this study, to suggest various methods to calculate contrast in the images of written text on the whiteboard in different lighting conditions. Brightness and contrast of text image were examined. Results shows that the suggested methods to calculate contrast edges points were enjoying high efficiency in specifying the contrast of text in mage. We may not, through these results, that text image contrast decreases by increasing the distance between camera and whiteboard