clear?all
%?source?=?aviread（‘C:\Video\Source\traffic\san_fran_traffic_30sec_QVGA‘）;
source?=?mmreader（‘E:\study\source\IndoorGTTest1.AVI‘）;
frameQYT=get（source‘NumberOfframes‘）;
%?-----------------------??frame?size?variables?-----------------------
fr?=?read（source1）;???????????%?讀取第一幀作為背景
fr_bw?=?rgb2gray（fr）;??????????%?將背景轉換為灰度圖像
fr_size?=?size（fr）;?????????????%取幀大小
width?=?fr_size（2）;
height?=?fr_size（1）;
fg?=?zeros（height?width）;
bg_bw?=?zeros（height?width）;
%?---------------------?mog?variables?-----------------------------------
C?=?4;??????????????????????????????????%?組成混合高斯的單高斯數目?（一般3-5）
M?=?0;??????????????????????????????????%?組成背景的數目
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?=?0.75;??????????????????????????%?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（heightwidthC）;??????????????%?initialize?weights?array?初始化權值數組
mean?=?zeros（heightwidthC）;???????????%?pixel?means?像素均值
sd?=?zeros（heightwidthC）;?????????????%?pixel?standard?deviations?像素標準差
u_diff?=?zeros（heightwidthC）;?????????%?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:height
????for?j=1:width
????????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--，這里去第八幀????
??????n?=?8;
????fr?=?read（sourcen）;???????%?read?in?frame?讀取幀
????fr_bw?=?rgb2gray（fr）;???????%?convert?frame?to?grayscale?轉換為灰度圖像
????
????%?calculate?difference?of?pixel?values?from?mean?計算像素差值
????for?m=1:C
????????u_diff（::m）?=?abs（double（fr_bw）?-?double（mean（::m）））;
????end
?????
????%?update?gaussian?components?for?each?pixel?更新每個像素的背景模型
????for?i=1:height
?????