imagegammacorrect

(PHP 3 >= 3.0.13, PHP 4, PHP 5)

imagegammacorrect -- 对 GD 图像应用 gamma 修正

说明

bool imagegammacorrect ( resource image, float inputgamma, float outputgamma )

imagegammacorrect() 函数用给定的输入 gamma 值 inputgamma 和输出 gamma 值 outputgamma 对一幅 GD 图像流(image)应用 gamma 修正。


add a note add a note User Contributed Notes
brian dot duncan at fife dot co dot uk
26-Jan-2002 09:46
Just thought I'd add how I used the gamma correction function (seeing as no-one had done so previously).  works great.

I used a form which has a parameter $GAMMA, so I usually type in something like 1.6

$image = ImageCreateFromJpeg ( "pictures/".$PICTURE2 ) ;
if ($GAMMA != "")
{
   $GammaFloat = (double) $GAMMA ;
   imagegammacorrect ($image, 1.0, $GammaFloat ) ;
       // now save the file
   imagejpeg ( $image, "pictures/"."$PICTURE2", 90 ) ;
}