matrix(); foreach ($image as $frame) { imageconvolution($frame->native(), $matrix, 1, 0); } return $image; } /** * Create matrix to be used by imageconvolution() * * @return array> */ private function matrix(): array { $min = $this->amount >= 10 ? $this->amount * -0.01 : 0; $max = $this->amount * -0.025; $abs = ((4 * $min + 4 * $max) * -1) + 1; return [ [$min, $max, $min], [$max, $abs, $max], [$min, $max, $min] ]; } }