Exercise number 1 in CMSC 165: Digital Image Processing
For our first exercise we are asked to select to kinds of images, one is an underexposed image and another is an over exposed image. And were asked to manipulate the intensity of the image, and have a points of reference to compare the changes occurred in the images.
For the underexposed image:
My point of reference in these pictures are the leaves at the upper left corner of the picture. Initially it is hard to distinguish the other leaves underneath the surface leaves but after increasing the intensity of the image. The leaves have become clearly distinguishable. And it can be seen in its histogram, the red lines represents the changed intensity while the green represents the normal line, where the red line can be seen to have curved upward from the dark values to the bright values, significantly.
For the overexposed image:
In these images the point of reference is the main bark of the tree found at the lower left corner of the picture where you cannot specify the patterns on the tree. But after lowering the values in the form of a parabolic curve, the pattern on the bark of the tree can be clearly seen.
In both sets of pictures above, two formulas for each were made. One is made to basically oppose the dominant nature of the picture and another is to handle the special case of the pictures, wherein a specific level of values is targeted to be manipulated by the second formula.