ABSTRACT
Pixel brightness can be revised by using pixel brightness techniques. There are two types of pixel brightness transformations: Position-dependent brightness correction and grayscale transformation. Grayscale transformation modifies the brightness of the pixel regardless of the position of the pixel. Grayscale transformations are mostly used if the outcome is seen by a human. Power-law transformation, also known as gamma correction transformation, is used to increase the contrast of an image. After the logarithmic transformation, the change of intensity information is spread out more equally making it simpler to analyze. There are two types of logarithmic transformation: log transformation and inverse log transformation. One way to improve the contrast of the image is contrast stretching. In contrast stretching, there exists a one-to-one relationship of the intensity values between the original or input image and the output image; that is, after contrast stretching the input image can be restored from the output image.
