Imagick::unsharpMaskImage

(PECL imagick 2.0.0)

Imagick::unsharpMaskImage — Sharpens an image

说明

bool Imagick::unsharpMaskImage ( float $radius , float $sigma , float $amount , float $threshold [, int $channel = Imagick::CHANNEL_ALL ] )

Sharpens an image. We convolve the image with a Gaussian operator of the given radius and standard deviation (sigma). For reasonable results, radius should be larger than sigma. Use a radius of 0 and Imagick::UnsharpMaskImage() selects a suitable radius for you.

参数

radius
sigma
amount
threshold
channel

返回值

成功时返回 TRUE .

错误/异常

错误时抛出 ImagickException .