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%高斯背景建模（）
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clear;
close?all;??%clear?obj?removes?obj?from?the?MATLAB?workspace.
tic;%計時開始%取第一幅符合要求的背景圖、
%?-----------------------??frame?size?variables?-----------------------
File_name=‘E:\學習\背景—車\背景建模圖片\‘;

str?=?int2str（1）;
T?=?STRCAT（File_namestr‘.jpg‘）;%
I?=?imread（T‘JPG‘）;
I=rgb2gray（I）;
I=I（:350:1000）;?
[mns]=size（I）;
q=zeros（mn）;
fg?=?q;??????????????%前景
bg_bw?=?q;???????????%背景

%?---------------------?mog?variables?-----------------------------------
C?=?3;??????????????????????????????????%?組成混合高斯的單高斯數目?（一般3-5）
M?=?3;??????????????????????????????????%?
D?=?2.5;????????????????????????????????%?閾值（一般2.5個標準差）
alpha?=?0.01;???????????????????????????%?learning?rate?學習率決定更新速度（between?0?and?1）?（from?paper?0.01）
thresh?=?0.25;??????????????????????????%?foreground?threshold?前景閾值（0.25?or?0.75?in?paper）
sd_init?=?6;????????????????????????????%?initial?standard?deviation?初始化標準差（for?new?components）?var?=?36?in?paper
w?=?zeros（mnC）;??????????????%?initialize?weights?array?初始化權值數組
mean?=?zeros（mnC）;???????????%?pixel?means?像素均值
sd?=?zeros（mnC）;?????????????%?pixel?standard?deviations?像素標準差
u_diff?=?zeros（mnC）;?????????%?difference?of?each?pixel?from?mean?與均值的差
p?=?alpha/（1/C）;????????????????????????%?initial?p?variable?參數學習率（used?to?update?mean?and?sd）
rank?=?zeros（1C）;??????????????????????%?rank?of?components?（w/sd）

%?------initialize?component?means?and?weights?初始化均值和權值----------

pixel_depth?=?8;????????????????????????%?8-bit?resolution?像素深度為8位
pixel_range?=?2^pixel_depth?-1;?????????%?pixel?range?像素范圍2的7次方0—255（#?of?possible?values）

for?i=1:m
????for?j=1:n
????????for?k=1:C
????????????
????????????mean（ijk）?=?rand*pixel_range;?????%?means?random?（0-255之間的隨機數）
????????????w（ijk）?=?1/C;?????????????????????%?weights?uniformly?dist
????????????sd（ijk）?=?sd_init;????????????????%?initialize?to?sd_init
????????????
????????end
????end
end

%-----?process?frames?-處理幀----------------------------------
E=10;??%背景序列個數
for?k?=?1:E??%迭代法更新背景??
?????str?=?int2str（k）;
?????T?=?STRCAT（File_namestr‘.jpg‘）;%
?????It?=?imread（T‘JPG‘）;
?????
?????fr_bw=rgb2gray（It）;
?????fr_bw=fr_bw（:350:1000）;?
?????%?calculate?difference?of?pixel?values?from?mean?計算像素差值
????for?l=1:C
????????u_diff（::l）?=?abs（double（fr_bw）?-?double（mean（::l）））;
????end
????
????%?update?gaussi