X l nh s

Ts.NG VN SI HC BCH KHOAI HC NNG

Chng 3 Tin x l Khi phc nh

M hnh gim cp Lc ngc Lc Wiener Lc thch nghi

Lm ni thuc tnh nh Histogram Cc ton t x l im Cc ton t Histogram Cc ton t khng gian Cc ton t bin i X l nh a ph X l nh mu

Khi phc nhM hnh gim cp

Khi phc nhM hnh gim cp

Khi phc nhLc ngc

Khi phc nhLc ngc

Khi phc nhLc Wiener

Khi phc nhLc Wiener

Khi phc nhLc thch nghi

Khi phc nhLc thch nghi

Lm ni thuc tnh nh Khi nim:

Trong mt bc nh c nhiu thng tin m ngi s dng quan tm, miloi thng tin khc nhau c tim n di mt thuc tnh khc nhau, v trch chn mt cch chnh xc cc thng tin ny cn phi lm nithuc tnh tng ng.

Vic lm ni thuc tnh ni chung khng lm giu thm thng tin trongbc nh m ch gip cho n l r. Khi lm ni thuc tnh ny th ccthuc tnh khc c th m nht, thm ch mt i, v vy kt qu x li khi lm cho bc nh xu i.

Phn loi : Cc thuc tnh histogram Cc thuc tnh khng gian Cc thuc tnh hnh hc Cc thuc tnh bin i Cc thuc tnh ph Cc thuc tnh mu sc

Lm ni thuc tnh nhHistogram

Khi nim: Histogram ca mt bc nh biu th tn sut xut

hin ca cc gi tr pixel trong bc nh L hnh nh ca hm mt xc sut xut hin cc

gi tr pixel.

Biu din theo 3 cch: Xc sut xut hin cc pixel : Pu( xi). T l phn trm (100xPu( xi)) S pixel c gi tr xi : h( xi).

Lm ni thuc tnh nhHistogram

3444026653201157444005573201050553444005753201056534443277532011

Pu(0) = 3/16, Pu(1) =3/32

Pu(2) = 3/32, Pu(3) =1/8

Pu(4) =3/16 , Pu(5) =3/16

Pu(6) =3/64 , Pu(7) =5/64

h(0)=12; h(1)=6; h(2)=6; h(3)=8;

h(4)=12; h(5)=12; h(6)=3; h(7)=5;

Pu( xi)

xi0 1 2 3 4 5 6 7

nh gi chi v tng phnda vo histogram

tng phn Histogram hp tng phn thp Histogram cng rng tng phn cng cao Histogram phn b u, tng phn l cc i.

chi (0 trng, L-1 en) Historam dn v bn tri, chi cao (tha sng) Historam dn v bn phi, chi thp (thiu sng)

Lm ni thuc tnh nhCc ton t x l im

Ko dn histogram Ct ngng Kh nhiu Chia mc cng To m bn s

F(.)u v = F(u)

Cc ton t x l imKo dn histogram

c tuyn vo rav

u

Pu(xi)Pv(xi)

0 a b L-1 xi.

0

L

-

1

x

i

.

0 L-1 xi.

11,

Lub )(ua )(

au0

>