Pimcore\Image\Adapter\Imagick::sharpen PHP Method

    public function sharpen($radius = 0, $sigma = 1.0, $amount = 1.0, $threshold = 0.05)
    {
        $this->preModify();
        $this->resource->normalizeImage();
        $this->resource->unsharpMaskImage($radius, $sigma, $amount, $threshold);
        $this->postModify();
        return $this;
    }