图像去雾质量评价MATLAB代码.rar

% 23/02/2011 % IFSTTAR copyright % % The approach is described in details in % % "Blind Contrast Restoration Assessment by Gradient Ratioing at Visible Edges", % by N. Hautiere, J.-P. Tarel, D. Aubert and E. Dumont, % in proceedings of International Congress for Stereology (ICS'07), % Saint Etienne, France, August 30-September 7, 2007. % http://perso.lcpc.fr/tarel.jean-philippe/publis/ics07.html % function [Mask Crr]=functionContrastAt5PerCent(I1,S,percentage) %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Inputs %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % I1 : Original image % S : SubWindow size (default = 7) % perCentage : Visibility percentage (default = 5) % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Outputs %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Mask : Mask of the visibility contrast > percentage % Crr : valeur du contraste visibile (>percentage) %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% if nargin<1 error('not enough argument') end if nargin<2 S=7; end if nargin<3 percentage=5; end [nl,nc,dd]=size(I1); %%% 4-neighborhood pixels seh=[0 1 0;0 1 0;0 0 0]; seg=[0 0 0;1 1 0;0 0 0]; %%% minimum and maximum calculation I1pad= padarray(I1,[3 3],'symmetric'); Igmin11=imerode(I1pad,seg,'full');%腐蚀 Ihmin11=imerode(I1pad,seh,'full'); Igmax11=imdilate(I1pad,seg,'full');%膨胀 Ihmax11=imdilate(I1pad,seh,'full'); Igmin1=Igmin11(3+(1:nl),3+(1:nc)); Ihmin1=Ihmin11(3+(1:nl),3+(1:nc)); Igmax1=Igmax11(3+(1:nl),3+(1:nc)); Ihmax1=Ihmax11(3+(1:nl),3+(1:nc)); %%% pads image and minimum and maximum matrix I1pad= padarray(I1,[S S],'symmetric'); Igmin1pad= padarray(Igmin1,[S S],'symmetric'); Ihmin1pad= padarray(Ihmin1,[S S],'symmetric'); Igmax1pad= padarray(Igmax1,[S S],'symmetric'); Ihmax1pad= padarray(Ihmax1,[S S],'symmetric'); %%% Initialization Is=zeros(S,S); Mask=false(nl+2*S,nc+2*S); Crr=zeros(nl+2*S,nc+2*S); s=1; percentage=percentage/2; h = waitbar(0,'Please wait...'); %%% subwindow of size S*S for ii=1:round(S/2):nl for jj=1:round(S/2):nc Is=double(I1pad(S+ii:2*S+ii-1,S+jj:2*S+jj-1)); Isgmin=double(Igmin1pad(S+ii:2*S+ii-1,S+jj:2*S+jj-1)); Ishmin=double(Ihmin1pad(S+ii:2*S+ii-1,S+jj:2*S+jj-1)); Isgmax=double(Igmax1pad(S+ii:2*S+ii-1,S+jj:2*S+jj-1)); Ishmax=double(Ihmax1pad(S+ii:2*S+ii-1,S+jj:2*S+jj-1)); %%% horizontal and vertical contrasts Cgxx1=zeros(1,S^2); Chxx1=zeros(1,S^2); Ismin=round(min(Is(:))); Ismax=round(max(Is(:))); if(Ismin<=0) Ismin=1;end if(Ismin>256) Ismin=256;end if(Ismax<=0) Ismax=1; end if(Ismax>256) Ismax=256;end Fcube=false(S,S,Ismax-Ismin+1); C=zeros(1,Ismax); G=zeros(1,Ismax); for s=Ismin:Ismax %%% we vary the threshold Fg=0; %%% Pixels cardinal separated by s pg=1; %%% Contrast indice Fh=0; ph=1; Cgxx1=zeros(1,S^2); Chxx1=zeros(1,S^2); for nn=2:S for mm=2:S %%% Vertical contrast if((Isgmin(nn,mm)<=s) && (Isgmax(nn,mm)>s))%%% test if two pixels are separated by s %%%% Weber Contrast calculation Cgxx1(pg)=min( abs(s-Is(nn,mm))/(max(s,Is(nn,mm))), abs(s-Is(nn,mm-1))/(max(s,Is(nn,mm-1)))); pg=pg+1; Fg=Fg+1; %% Mask calculation Fcube(nn,mm,s-Ismin+1)=true; Fcube(nn,mm-1,s-Ismin+1)=true; end %%% Horizontal contrast if((Ishmin(nn,mm)<=s) && (Ishmax(nn,mm)>s)) %%%% Weber Contrast calculation Chxx1(ph)=min( abs(s-Is(nn,mm))/(max(s,Is(nn,mm))) , abs(s-Is(nn-1,mm))/(max(s,Is(nn-1,mm))) ); ph=ph+1; Fh=Fh+1; %% Mask calculation Fcube(nn,mm,s-Ismin+1)=true; Fcube(nn-1,mm,s-Ismin+1)=true; end end end if ((Fg+Fh) > 0) %%% we verified if there is a threshold s that separates at least two pixels C(s)=(1/(Fg+Fh))*(sum(Cgxx1)+sum(Chxx1)); %% Contrast of threshold s end end %%% threshold that maximize the contrast [M s0] = max(C); s0=max(s0,Ismin); M=256*M; if(M>(256*(percentage/100))) %%% overlapping : we make a "logical |" because we evaluate contrast in windows of size S moving with a step of S/2 Mask(S+ii:2*S+ii-1,S+jj:2*S+jj-1) = Mask(S+ii:2*S+ii-1,S+jj:2*S+jj-1) | Fcube(:,:,s0-Ismin+1); I3=Mask(S+ii:2*S+ii-1,S+jj:2*S+jj-1); %%% recover the contrast value of visible edge Crr1=zeros(S,S); Crr1(I3)=2*M/256; Crr(S+ii:2*S+ii-1,S+jj:2*S+jj-1)=Crr1; end end waitbar(ii/nl,h) end Mask=Mask(S+1:nl+S,S+1:nc+S); Crr=Crr(S+1:nl+S,S+1:nc+S); close(h);