颜色特征提取，hsv颜色空间，使用颜色直方图,采用非均匀量化

color.m

%=============================
%颜色特征提取，hsv颜色空间，使用颜色直方图,采用非均匀量化
%=============================
function fc=color(imgname)
%tic
img=imread(imgname);
hsv=rgb2hsv(img);
%将hsv特征进行非均匀的量化
[height,width,dim]=size(hsv);
len=256;
fc=zeros(1,len);
for i=1:height,
    for j=1:width,
        H=hsv(i,j,1)*360;
        S=hsv(i,j,2);
        V=hsv(i,j,3);
        %非均匀化H
        if H<=15 || H>345,
            h=0;
        elseif H>15 && H<=25,
            h=1;
        elseif H>25 && H<=45,
            h=2;
        elseif H>45 && H<=55,
            h=3;
        elseif H>55 && H<=80,
            h=4;
        elseif H>80 && H<=108,
            h=5;
        elseif H>108 && H<=140,
            h=6;
        elseif H >140 && H<=165,
            h=7;
        elseif H >165 && H<=190,
            h=8;
        elseif H>190 && H<=220,
            h=9;
        elseif H>220 && H<=255,
            h=10;
        elseif H>255 && H<=275,
            h=11;
        elseif H>275 && H<=290,
            h=12;
        elseif H>290 && H<=316,
            h=13;
        elseif H>316 && H<330,
            h=14;
        else 
            h=15;
        end
        %非均匀化S
        if S >=0 && S<=0.15,
            s=0;
        elseif S>0.15 && S<=0.4,
            s=1;
        elseif S>0.4 && S<=0.75,
            s=2;
        else 
            s=3;
        end
        %非均匀化V
        if V >=0 && V<=0.15,
            v=0;
        elseif V>0.15 && V<=0.4,
            v=1;
        elseif V>0.4 && V<=0.75,
            v=2;
        else 
            v=3;
        end
        %计算L
        L=16*h+4*s+v+1;
        fc(L)=fc(L)+1;
    end
end
fc=fc/sum(fc);
%toc
end