(PHP 4, PHP 5, PHP 7)
Apply a gamma correction to a GD image
bool imagegammacorrect ( resource $image, float $inputgamma, float $outputgamma )
Applies gamma correction to the given gd image given an input and an output gamma.
Parameters:
image
An image resource, returned by one of the image creation functions, such as imagecreatetruecolor().
inputgamm