(PECL imagick 2.0.0)
Imagick::sharpenImage — Sharpens an image
$radius
, float $sigma
[, 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, the radius should be larger than sigma. Use a radius of 0 and selects a suitable radius for you.
radius
sigma
channel
Returns TRUE
on success.