PHP Manual: Surrounds the image with a border

bool Imagick::borderImage ( mixed $bordercolor , int $width , int $height )

Surrounds the image with a border of the color defined by the bordercolor ImagickPixel object.

bordercolor: ImagickPixel object or a string containing the border color
width: Border width
height: Border height

Returns TRUE on success.

Version	Description
2.1.0	Now allows a string representing the color as the first parameter. Previous versions allow only an ImagickPixel object.