opencv/cxcore.go
func Xor(src1, src2, dst *IplImage) {
	XorWithMask(src1, src2, dst, nil)
}
func Xor(src1, src2, dst *IplImage) {
	XorWithMask(src1, src2, dst, nil)
}
// Calculates the per-element bit-wise “exclusive or” operation on two arrays.