Figure 2(a–d) with impulse noise filtered by FMBF. (a1–a4) show Figure 2(a) with impulse noise of 10%, 20%, 30% and 40%, respectively; (b1–b4) show the results of (a1–a4) filtered by FMBF once, once, two times and three times, respectively; (c1–c4) show Figure 2(b) with impulse noise of 10%, 20%, 30% and 40%, respectively; (d1–d4) show the results of (c1–c4) filtered by FMBF once, once, two times and three times, respectively; (e1–e4) show Figure 2(c) with impulse noise of 10%, 20%, 30% and 40%, respectively; (f1–f4) show the results of (e1–e4) filtered by FMBF once, once, two times and three times, respectively; (g1–g4) show Figure 2(d) with impulse noise of 10%, 20%, 30% and 40%, respectively; (h1–h4) show the results of (g1–g4) filtered by FMBF once, once, two times and three times, respectively.