opencv/imgproc.go
func ArcLength(curve *Seq, slice Slice, is_closed bool) float64 {
	is_closed_int := 0
	if is_closed {
		is_closed_int = 1
	}
	return float64(C.cvArcLength(unsafe.Pointer(curve),
		(C.CvSlice)(slice),
		C.int(is_closed_int)))
}
func ArcLength(curve *Seq, slice Slice, is_closed bool) float64 {
	is_closed_int := 0
	if is_closed {
		is_closed_int = 1
	}
	return float64(C.cvArcLength(unsafe.Pointer(curve),
		(C.CvSlice)(slice),
		C.int(is_closed_int)))
}
// cvArcLength(const void* curve, CvSlice slice=CV_WHOLE_SEQ, int is_closed=-1 )