%'hist_update': update of a current global histogram by inclusion of a new field %------------------------------------------------------------------------ %[val,HIST]=hist_update(val,HIST,C,dC) % % OUTPUT: % val: vector of field values at which the histogram is determined (middle of bins) % HIST(:,icolor): nbre of occurence of the field value in the bins whose middle is given by val % can be a column vector, same size as val, or a matrix with three columns, for color images % % INPUT: % val: existing field values from the current histogram, =[] if there is no current histogram % HIST(:,icolor): current histogram, =[] if there is none % can be a column vector (icolor=1), same size as val, or a matrix with three columns, for color images % C(:,icolor): vector representing the current field values % can be a column vector (icolor=1), or a matrix with three columns, for color images % dC: width of the new bins extending val to account for the new field. %======================================================================= % Copyright 2008-2016, LEGI UMR 5519 / CNRS UGA G-INP, Grenoble, France % http://www.legi.grenoble-inp.fr % Joel.Sommeria - Joel.Sommeria (A) legi.cnrs.fr % % This file is part of the toolbox UVMAT. % % UVMAT is free software; you can redistribute it and/or modify % it under the terms of the GNU General Public License as published % by the Free Software Foundation; either version 2 of the license, % or (at your option) any later version. % % UVMAT is distributed in the hope that it will be useful, % but WITHOUT ANY WARRANTY; without even the implied warranty of % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the % GNU General Public License (see LICENSE.txt) for more details. %======================================================================= function [val,HIST]=hist_update(val,HIST,C,dC) valplus=[];valminus=[]; HISTplus=[];HISTminus=[]; if isempty(HIST) HIST=0; end siz=size(C);nbfields=siz(2); C=double(C); valmin=min(val); valmax=max(val); Cmin=min(min(C)); Cmax=max(max(C)); if isempty(val)%no current histogram val=[Cmin-dC/2:dC:Cmax+dC/2]; else %extending the current histogram beyond its maximum value if Cmax>=valmax+dC/2; valplus=[valmax+dC:dC:Cmax+dC/2];% we extend the values val HISTplus=zeros(length(valplus),nbfields);% we put histogram to zero at these values end %extending the current histogram below its minimum value if Cmin<=valmin-dC/2; valminus=[valmin-dC:-dC:Cmin-dC/2];% we extend the values val valminus=sort(valminus);% we reverse the order HISTminus=zeros(length(valminus),nbfields);% we put histogram to zero at these values end val=[valminus val valplus]; end HIST=[HISTminus;HIST;HISTplus]; if nbfields==1 histC=(hist(C,val))';% initiate the global histogram elseif nbfields==3 HIST1=(hist(C(:,1),val))'; HIST2=(hist(C(:,2),val))'; HIST3=(hist(C(:,3),val))'; histC=[HIST1 HIST2 HIST3]; end HIST=HIST+histC;