gamma correction formula : .^(gamma) or .^(1/gamma)?

Question

I\'m looking for a simple gamma correction formula for grayscale images with values between 0 and 255.

Let\'s say that the gamma of my screen is 2.2 (it\'s an LCD screen

Answer 1

Gamma correction controls the overall brightness of an image. Images which are not corrected can look either bleached out or too dark. Suppose a computer monitor has 2.2 power function as an intensity to voltage response curve. This just means that if you send a message to the monitor that a certain pixel should have intensity equal to x, it will actually display a pixel which has intensity equal to x^2.2 Because the range of voltages sent to the monitor is between 0 and 1, this means that the intensity value displayed will be less than what you wanted it to be. Such a monitor is said to have a gamma of 2.2.

So in your case,

Corrected = 255 * (Image/255)^(1/2.2).