Why is Mat used for in Range instead of a scalar wit hsv? And how can I sat Mat to a lower HSV range? about gocv HOT 2 CLOSED

func TestMatInRange(t *testing.T) {
	mat1 := NewMatWithSize(101, 102, MatTypeCV8U)
	defer mat1.Close()
	lb := NewMatFromScalar(NewScalar(20.0, 100.0, 100.0, 0.0), MatTypeCV8U)
	defer lb.Close()
	ub := NewMatFromScalar(NewScalar(20.0, 100.0, 100.0, 0.0), MatTypeCV8U)
	defer ub.Close()
	dst := NewMat()
	defer dst.Close()
	InRange(mat1, lb, ub, &dst)
	if dst.Empty() {
		t.Error("TestMatAddWeighted dest mat3 should not be empty.")
	}
}