$amount
$amount : integer
Change the contrast of an image. Contrast is the difference in luminance or colour that makes an object distinguishable.
apply(\Grafika\Gd\Image $image) : \Grafika\Gd\Image
| \Grafika\Gd\Image | $image |
<?php
namespace Grafika\Gd\Filter;
use Grafika\FilterInterface;
use Grafika\Gd\Image;
/**
* Change the contrast of an image. Contrast is the difference in luminance or colour that makes an object distinguishable.
*/
class Contrast implements FilterInterface{
/**
* @var int
*/
protected $amount; // -100 >= 0 >= 100
/**
* Contrast constructor.
* @param int $amount The amount of contrast to apply. >= -100 and <= -1 to reduce. 0 for no change. >= 1 and <= 100 to increase.
*/
public function __construct($amount)
{
$this->amount = (int) $amount;
}
/**
* @param Image $image
*
* @return Image
*/
public function apply( $image ) {
imagefilter($image->getCore(), IMG_FILTER_CONTRAST, ($this->amount * -1));
return $image;
}
}