%%%%%%%%%%%%%%%%遺傳算法在道路圖像閾值分割中的應(yīng)用%%%%%%%%%%%%
function?main（）
clear?all
close?all
clc
global?chrom?oldpop?fitness?lchrom??popsize?cross_rate?mutation_rate?thresholdsum
global?maxgen??m?n?fit?gen?threshold?A?B?C?oldpop1?popsize1?b?b1?fitness1?threshold1
A=imread（‘1.jpg‘）;?????%讀入道路圖像
A=imresize（A0.5）;?????%利用imresize函數(shù)通過默認(rèn)的最近鄰插值將圖像放大0.5倍
B=rgb2gray（A）;?????????%灰度化
C=imresize（B0.2）;?????%將讀入的圖像縮小到0.2倍
lchrom=10;??????????????%染色體長(zhǎng)度
popsize=10;????????????%種群大小
cross_rate=0.8;????????%交叉概率
mutation_rate=0.5;?????%變異概率
maxgen=100;????????????%最大代數(shù)
[mn]=size（C）;
initpop;????%初始種群
for?gen=1:maxgen
????generation;??%遺傳操作
end
findthreshold_best;?%圖象分割結(jié)果
%%%%%%%%%%%%%%%%%%%輸出進(jìn)化各曲線%%%%%%%%%%%
figure;
gen=1:maxgen;
plot（genfit（1gen））;?
title（‘最佳適應(yīng)度值進(jìn)化曲線‘）;
xlabel（‘代數(shù)‘）
ylabel（‘最佳適應(yīng)度值‘）
figure;
plot（genthreshold（1gen））;
title（‘每一代的最佳閾值變化曲線‘）;
xlabel（‘代數(shù)‘）
ylabel（‘每一代的最佳閾值‘）
%%%%%%%%%%%%%%%%%%%初始化種群%%%%%%%%%%%%%%%%%%%%
function?initpop（）
global?lchrom?oldpop?popsize?chrom?C
imshow（C）;
for?i=1:popsize
????chrom=rand（1lchrom）;
????for?j=1:lchrom
????????if?chrom（1j）<0.5
????????????chrom（1j）=0;
???????else?
???????????chrom（1j）=1;
????????end
????end
????oldpop（i1:lchrom）=chrom;????%給每一個(gè)個(gè)體分配8位的染色體編碼
end

%%%%%%%%%%%%%%%%%產(chǎn)生新一代個(gè)體%%%%%%%%%%%%%%%%%%%%%%
function?generation（）
fitness_order;??????????????????%計(jì)算適應(yīng)度值及排序
select;?????????????????????????%選擇操作
crossover;??????????????????????%交叉
mutation;???????????????????????%變異
%%%%%%%%%%%%%%%%%計(jì)算適度值并且排序%%%%%%%%%%%%%%%%%%%
function?fitness_order（）
global?lchrom?oldpop?fitness?popsize?chrom?fit?gen?C?m?n??fitness1?thresholdsum
global?lowsum?higsum?u1?u2?threshold?gen?oldpop1?popsize1?b1?b?threshold1?
if?popsize>=5
????popsize=ceil（popsize-0.03*gen）;
end
if?gen==75?????%當(dāng)進(jìn)化到末期的時(shí)候調(diào)整種群規(guī)模和交叉、變異概率
????cross_rate=0.3;????????%交叉概率
????mutation_rate=0.3;?????%變異概率
end
%如果不是第一代則將上一代操作后的種群根據(jù)此代的種群規(guī)模裝入此代種群中
if?gen>1???
????t=oldpop;
????j=popsize1;
????for?i=1:popsize
????????if?j>=1
????????????oldpop（i:）=t（j:）;
????????end
????????j=j-1;
????end
end
%計(jì)算適度值并排序
for?i=1:popsize
????lowsum=0;
????higsum=0;
????lownum=0;
????hignum=0;
????chrom=oldpop（i:）;
????c=0;
????for?j=1:lchrom
????????c=c+chrom（1j）*（2^（lchrom-j））;
????end
????b（1i）=c*255/（2^lchrom-1）;??%轉(zhuǎn)化到灰度值????????
????for?x=1:m
????????for?y=1:n
????????????if?C（xy）<=b（1i）
????????????????lowsum=lowsum+double（C（xy））;%統(tǒng)計(jì)低于閾值的灰度值的總和
????????????????lownum=lownum+1;?%統(tǒng)計(jì)低于閾值的灰度值的像素的總個(gè)數(shù)
????????????else
????????????????higsum=higsum+double（C（xy））;%統(tǒng)計(jì)高于閾值的灰度值的總和
????????????????hignum=hignum+1;?%統(tǒng)計(jì)高于閾值的灰度值的像素的總個(gè)數(shù)
????????????end
????????end
????end
????if?lownum~=0
????????u1=lowsum/lownum;?%u1、u2為對(duì)應(yīng)于兩類的平均灰度值
????else
????????u1=0;
????end
????if?hignum~=0
????????u2=higsum/hignum;
????else
????????u2=0;
????end???
????fitness（1i）=lownum*hignum*（u1-u2）^2;?%計(jì)算適度值
end
if?gen==1?%如果為第一代，從小往大排序
????for?i=1:popsize
????????j=i+1;
????????while