Imagick::evaluateImage
(PECL imagick 2, PECL imagick 3)
Imagick::evaluateImage — Applies an expression to an image
Descrição
public Imagick::evaluateImage(int $op
, float $constant
, int $channel
= Imagick::CHANNEL_DEFAULT): bool
Parâmetros
-
op
-
The evaluation operator
-
constant
-
The value of the operator
-
channel
-
Provide any channel constant that is valid for your channel mode. To
apply to more than one channel, combine channeltype constants using
bitwise operators. Refer to this
list of channel constants.
Valor Retornado
Retorna true
em caso de sucesso.
Erros
Lança uma exceção ImagickException em caso de erro.
Exemplos
Exemplo #1 Using Imagick::evaluateImage()
Using evaluateImage to reduce opacity in an image.
<?php
// Create new object with the image
$im = new Imagick('example-alpha.png');
// Reduce the alpha by 50%
$im->evaluateImage(Imagick::EVALUATE_DIVIDE, 2, Imagick::CHANNEL_ALPHA);
// Output the image
header("Content-Type: image/png");
echo $im;
?>