(PECL imagick 2.0.0)
Imagick::sketchImage — Simulates a pencil sketch
Simulates a pencil sketch. 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::sketchImage() selects a suitable radius for you. Angle gives the angle of the blurring motion. This method is available if Imagick has been compiled against ImageMagick version 6.2.9 or newer.
The radius of the Gaussian, in pixels, not counting the center pixel
The standard deviation of the Gaussian, in pixels.
Apply the effect along this angle.
TRUE on success.