DigitalImageProcessing_base_on_Matlab 基于Matlab的数字图像处理

				%函数LBG.m: LBG训练法%
				function [I_codebook,O_distortion]=LBG(t_image,nc,nd,th)
				%I_codebook:最后所得的码本%
				%O_distortion:向量到最后所得码本之间的平均误差%
				%t_image:训练数据%
				
				%Rearrangement of the training image%
				[row,col]=size(t_image);
				nt=row*col/nd;
				R_image=[];
				sqrt_nd=sqrt(nd);
				x_count=fix(col/sqrt_nd);
				y_count=fix(row/sqrt_nd);
				for i=1:1:y_count
				   for j=1:1:x_count
				      r_image=t_image((i-1)*sqrt_nd+1:i*sqrt_nd,(j-1)*sqrt_nd+1:j*sqrt_nd);
				      R_image=[R_image;r_image(1:nd)];
				   end
				end
				%Read training data and group the data into training vectors%
				ratio=fix(y_count*x_count/nt);
				T_image=[];
				for i=1:ratio:ratio*nt
				   T_image=[T_image;R_image(i,1:nd)];
				end
				
				%制造初始码本%
				ratio=fix(y_count*x_count/nc);
				I_codebook=[];
				for i=1:ratio:ratio*nc
				   I_codebook=[I_codebook;R_image(i,1:nd)];
				end
				%LBG Algorithm%
				disp('Begin LBG algorithm,and wait........');
				Dt=[];
				converge=1;
				I_count=1;
				Dt(1)=inf;
				while(converge)
				   %步骤1: 将码本内容当作重心，将所有的向量分类至这些区间%  
				   T_dis=0;
				   for i=1:1:nt
				      P_dis=inf;
				      P_index=0;
				      %将每一个向量均归类到与其距离最短的重心那一类%
				      for j=1:1:nc
				         dis=((T_image(i,:)-I_codebook(j,:))*(T_image(i,:)-I_codebook(j,:))');
				         if dis				            P_dis=dis;
				            P_index=j; %归类
				         end
				      end
				      T_dis=T_dis+P_dis/nd;
				      id(i)=P_index;
				   end
				   Dt=[Dt,T_dis/nt];
				   %步骤2: 重新计算每一个分类区间的重心并取代先前的码本内容%
				   for i=1:1:nc
				      count=0;
				      U_codebook=zeros(1,nd);
				      for j=1:1:nt
				         if id(j)==i
				            U_codebook=U_codebook+T_image(j,:);
				            count=count+1;
				         end
				      end
				      if count>0
				         I_codebook(i,1:nd)=U_codebook/count;
				      end
				   end
				   %步骤3: 计算并判断向量到其分类重心之间的平均误差是否小于收敛值th% 
				   disp('Distortion of current iteration =');
				   disp(T_dis/nt);
				   I_count=I_count+1;
				   %判断前一次和这一次平均误差的修正值是否小于th% 
				   if abs((Dt(I_count-1)-Dt(I_count))/Dt(I_count-1))				      converge=0;
				   end
				end
				O_distortion= T_dis/nt;        %最后的平均误差
				disp('End of the LBG algorithm');