(PECL imagick 2.0.0)
Blurs an image
bool Imagick::gaussianBlurImage ( float $radius, float $sigma [, int $channel = Imagick::CHANNEL_ALL ] )
Blurs 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.
Parameters: