FRFTl滤波、结合仿射变换图像加密代码

function tfrqview(tfr,sig,t,method,p1,p2,p3,p4,p5); %TFRQVIEW Quick visualization of time-frequency representations. % TFRQVIEW(TFR,SIG,T,METHOD,P1,P2,P3,P4,P5) allows a quick % visualization of a time-frequency representation. % % TFR : time-frequency representation (MxN). % SIG : signal in time. If unavailable, put sig=[] as input % parameter. (default : []). % T : time instants (default : 1:N). % METHOD : name of chosen representation (default : 'TYPE1'). % See the TFR* files for authorized names. % TYPE1 : the representation TFR goes in normalized % frequency from -0.5 to 0.5 ; % TYPE2 : the representation TFR goes in normalized % frequency from 0 to 0.5. % P1...P5 : optional parameters of the representation : run the % file TFRPARAM(METHOD) to know the meaning of P1..P5 % for your method. % % When you use the 'save' option in the main menu, you save all your % variables as well as two strings, TfrQView and TfrView, in a mat % file. If you load this file and do eval(TfrQView), you will restart % the display session under tfrqview ; if you do eval(TfrView), you % will obtain the exact layout of the screen you had when clicking on % the 'save' button. % % Example : % sig=fmsin(128); tfr=tfrwv(sig); % tfrqview(tfr,sig,1:128,'tfrwv'); % % See also TFRVIEW, TFRSAVE, TFRPARAM. % F. Auger, September 1994, July 1995 % O. Lemoine, Oct 1995, May-July 1996. % Copyright (c) 1996 by CNRS (France). % % ------------------- CONFIDENTIAL PROGRAM -------------------- % This program can not be used without the authorization of its % author(s). For any comment or bug report, please send e-mail to % f.auger@ieee.org comp=computer; % Tests on the input arguments if nargin<1, error('At least one parameter required'); end [tfrrow,tfrcol]=size(tfr); if nargin==1, sig=[]; t=1:tfrcol; method='type1'; elseif nargin==2, t=1:tfrcol; method='type1'; elseif nargin==3, method='type1'; end [trow,tcol] = size(t); if (trow~=1), error('T must only have one row'); end; if (tfrcol~=tcol), error('T must have as much elements as tfr has columns'); end; method=upper(method); [Nsig,Ncol]=size(sig); if Ncol>2, error('SIG must have less than two columns'); end % Computation of Nf2, the number of interresting points in frequency method=upper(method); if strcmp(method,'TFRWV' ) | strcmp(method,'TFRPWV' ) | ... strcmp(method,'TFRSPWV' ) | strcmp(method,'TFRCW' ) | ... strcmp(method,'TFRZAM' ) | strcmp(method,'TFRBJ' ) | ... strcmp(method,'TFRBUD' ) | strcmp(method,'TFRGRD' ) | ... strcmp(method,'TFRRSPWV') | strcmp(method,'TFRRPWV' ) | ... strcmp(method,'TFRRIDB' ) | strcmp(method,'TFRRIDH' ) | ... strcmp(method,'TFRRIDT' ) | strcmp(method,'TFRASPW' ) | ... strcmp(method,'TFRDFLA' ) | strcmp(method,'TFRSPAW' ) | ... strcmp(method,'TFRRIDBN') | strcmp(method,'TFRUNTER') | ... strcmp(method,'TFRBERT' ) | strcmp(method,'TFRSCALO') | ... strcmp(method,'TYPE2' ), Nf2=tfrrow; elseif strcmp(method,'TFRPMH' )| strcmp(method,'TFRRPMH' )| ... strcmp(method,'TFRSP' )| strcmp(method,'TFRRSP' )| ... strcmp(method,'TFRPPAGE')| strcmp(method,'TFRRPPAG')| ... strcmp(method,'TFRMHS' )| strcmp(method,'TFRRGAB' )| ... strcmp(method,'TFRMH' )| strcmp(method,'TFRMMCE' )| ... strcmp(method,'TFRRMSC' )| strcmp(method,'TFRPAGE' )| ... strcmp(method,'TFRGABOR')| strcmp(method,'TFRRI' )| ... strcmp(method,'TFRMSC' )| strcmp(method,'TYPE1' )| ... strcmp(method,'TFRSTFT' ), Nf2=tfrrow/2; else error('Unknown representation. Use type1 or type2'); end; % Computation of freq (vector of frequency samples) if strcmp(method,'TFRASPW' ) | strcmp(method,'TFRSCALO') | ... strcmp(method,'TFRDFLA' ) | strcmp(method,'TFRSPAW' ) | ... strcmp(method,'TFRUNTER') | strcmp(method,'TFRBERT' ), freq=eval(['p',num2str(nargin-4)]); % last input argument is freqs. else freq=(0.5*(0:Nf2-1)/Nf2); end % Initialization of the current figure zoom off; clf; set(gcf,'Resize','On','NextPlot','Add'); % Initialization of the variables if exist('options.mat'), load options else threshold=5.0; linlogtfr=0; linlogspec=1; levelnumb=6; colmap=1; display=1; layout=1; iscolorbar=0; isgridsig=0; isgridspe=0; isgridtfr=0; issig=0; isspec=0; end choice=4; Grid=1; displayold=1; fs=1.0; if ((layout>=2 & layout<=4) & sig==[]), layout=1; end % Initialization of the axes axcb = axes('Units','normal','Visible','off','Box','On'); axsig = axes('Units','normal','Visible','off','Box','On'); axspec = axes('Units','normal','Visible','off','Box','On'); axtfr = axes('Units','normal','Visible','off','Box','On'); if comp(1:2)=='PC', set(axsig ,'fontsize',10); set(axspec,'fontsize',10); set(axtfr ,'fontsize',10); end set(gcf,'UserData',[axcb axsig axspec axtfr]); % Test of analycity if sig~=[], for k=1:Ncol, spec(:,k)=abs(fft(sig(min(t):max(t),k))).^2; Nsp=length(spec); spec1=sum(spec(1:Nsp/2,k)); spec2=sum(spec(Nsp/2+1:Nsp,k)); if spec2>spec1/10, disp('Be careful : the signal is not analytic!'); end end end % Test of reality if (Ncol==2 & ~isreal(tfr)), disp('Cross distribution. As the result is complex, we display the real part.'); tfr=real(tfr); end while choice~=12, axes(axtfr); % The current axis is the tfr axis if (display~=7 & choice~=2 & choice~=3 & choice<8), % Call to tfrview linlog=linlogtfr+2*linlogspec; if choice==4, access=3; else access=1; end state=issig+2*iscolorbar; isgrid=isgridsig+2*isgridspe+4*isgridtfr; param = [display,linlog,threshold,levelnumb,Nf2,layout,access,state,fs,isgrid]; map=colormap; if (nargin<=4), tfrview(tfr,sig,t,method,param,map); elseif (nargin==5), tfrview(tfr,sig,t,method,param,map,p1); elseif (nargin==6), tfrview(tfr,sig,t,method,param,map,p1,p2); elseif (nargin==7), tfrview(tfr,sig,t,method,param,map,p1,p2,p3); elseif (nargin==8), tfrview(tfr,sig,t,method,param,map,p1,p2,p3,p4); elseif (nargin==9), tfrview(tfr,sig,t,method,param,map,p1,p2,p3,p4,p5); end; elseif (display==7), % keep in mind the last value of display display=displayold; end if (linlogtfr==0), % Lin/log scale of the tfr linlogstr='Change to a logarithmic scale'; else linlogstr='Change to a linear scale'; end; % Main menu choice=menu ('TFRQVIEW MENU :',... 'Change the display mode',... 'Change the display layout',... 'Change the color map',... 'Change the sampling frequency',... 'Change the threshold',... linlogstr,... 'Change the number of levels',... 'Grid',... 'Save',... 'Save options',... 'Print',... 'Close'); if ((choice==9 | choice==11) & comp(1:2)~='PC'), if exist('workdir.mat'), load workdir; else Path=pwd; str1=[' The current directory is ',Path]; disp(str1); disp(''); continue=0; while continue==0, continue=1; str2=' Name of the directory (with full path) on which the files will be saved : '; disp(str2); PathWorkDir=input(' > ','s'); if (exist(PathWorkDir)~=2), rep=input(' This directory doesn''t exist. Do you want to create it (y/n) ? ','s'); if upper(rep)=='Y', eval(['!mkdir ',PathWorkDir]); else continue=0; end end end if PathWorkDir(length(PathWorkDir))~='/', PathWorkDir=[PathWorkDir,'/']; end save workdir PathWorkDir; end end if (choice==1), % Change the display mode display=menu('DISPLAY MODE :',... 'Contour',... 'Imagesc',... 'Pcolor',... 'Surf',... 'Mesh',... 'Cancel'); elseif (choice==2)