##Brightness
The brightness
method adjusts the brightness of the Image
. The method accepts a value between -100
and 100
.
$image->brightness(-20);

##Contrast
The contrast
method adjusts the contrast of the Image
. The method accepts a value between -100
and 100
.
$image->contrast(20);

##Gamma
The gamma
method adjusts the gamma of the Image
. The method accepts a value between 0.1
and 9.99
.
$image->gamma(4.1);
