Imagick::evaluateImage

(PECL imagick 2.0.0)

Imagick::evaluateImage — Applies an expression to an image

说明

bool Imagick::evaluateImage ( int $op , float $constant [, int $channel=Imagick::CHANNEL_ALL ] )

Warning

本函数暂无文档，仅有参数列表。

Applys an arithmetic, relational, or logical expression to an image. Use these operators to lighten or darken an image, to increase or decrease contrast in an image, or to produce the "negative" of an image.

参数

op: The 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. Defaults to Imagick::CHANNEL_ALL. Refer to this list of channel constants.

返回值

Returns TRUE on success.

错误／异常

Throws ImagickException on error.