数字图像处理 姚敏 代码

f=imread('peppers.bmp'); [m,n]=size(f); pow2size=2^nextpow2(max(m,n)); if m~=n||m~=pow2size error('图像必须是方的且大小为2的整数次幂'); end subplot(2,2,1); imshow(f); title('原始图像'); std_thresh=10; min_dim=2; g=split_merge(f,min_dim,@predicate_fun,std_thresh); g=mat2gray(g); subplot(2,2,2); imshow(g); title('分裂最小子区域大小2*2'); function g=split_merge(f,min_dim,predicate_fun,std_thresh) spare_qtim=qtdecomp(f,@split_test_fun,min_dim,@predicate_fun,std_thresh); max_block_size=full(max(spare_qtim(:))); maskim=zeros(size(f)); markerim=zeros(size(f)); for i=1:max_block_size [val,r,c]=qtgetblk(f,spare_qtim,i); if numel(val)~=0 for numel(val)~=0 for j=1:length(r) xlow=r(j); ylow=c(j); xhigh=xlow+i-1; yhigh=ylow+i-1; subblock=f(xlow:xhigh,ylow:yhigh); flag=feval(predicate_fun,subblock,std_thresh); if flag maskim(xlow:xhigh,ylow:yhigh)=1; markerim(xlow:xhigh,ylow:yhigh)=1; end end end end g=bwlabel(imreconstruct(markerim,maskim),8); function splitflag=split_test_fun(subblocks_im,min_dim,predicate_fun,std_thresh) block_num=size(subblocks_im,3); splitflag((1:block_num)=false; for i=1:block_num subblock=subblocks_im(:,:,i); if(size(subblock,1))<=min_dim splitflag(i)=false; continue end flag=feval(predicate_fun,subblock,std_thresh); if flag splitflag(i)=true; end end function flag=predicate_fun(subblock_im,std_thresh) stdval=std2(subblock_im); flag=stdval>std_thresh;