def calculaarlalineacentro(x1, x2, gx, gy, image):
tangente1 = [x1, x2[1]-(gx*x1[0])]
t2 = [gy, x2[1]-(gy*x2[0])]
x = float(t2[1]-tan1[1]) / (tan1[0]-t2[0])
y = tan1[0]*x+ tan1[1]
inter = (x, y)
medio = ( (x1[0]+x2[0])/2, (x1[1]+x2[1])/2 )
if (inter[0]-medio[0]) != 0:m = (inter[1]-medio[1] ) / (inter[0]-medio[0])
else:m = 1000
b = medio[1] - (m*medio[0])
lineadelcentro = [m, b]
if (inter[0]-medio[0]) < 0.0:dire = 1
else:direcc = -1