(PECL imagick 2 >= 2.3.0, PECL imagick 3)
Imagick::getImageChannelDistortions — Gets channel distortions
$reference, int $metric, int $channel = Imagick::CHANNEL_DEFAULT): floatCompares one or more image channels of an image to a reconstructed image and returns the specified distortion metrics 此方法在Imagick基于ImageMagick 6.4.4以上版本编译时可用。
referenceImagick object containing the reference image
metricRefer to this list of metric type constants.
channel
Provide any channel constant that is valid for your channel mode. To apply to more than one channel, combine channel constants using bitwise operators. 缺省为Imagick::CHANNEL_DEFAULT.
参考此 通道常数列表
Returns a float describing the channel distortion.
错误时抛出 ImagickException。