GVF-snake.zip_SNAKE matlab 分割_matlab 医学_snake 医学_分割算法_医学matlab

function [X,map] = rawread(filename,n,m); % RAWREAD Read a Portable Bitmap file, or a raw file. % RAWREAD('imagefile.raw', xsize, ysize) reads a "raw" image file % RAWREAD('imagefile.pgm') reads a "pgm" (portable gray map) image % [X,map] = RAWREAD('imagefile.raw') returns both the image and a % color map, so that % [X,map] = rawread('imagefile.raw',sx,sy); % or [X,map] = rawread('imagefile.pgm'); % image(X) % colormap(map) % will display the result with the proper colors. % % NOTE : map is optional and could be replaced during the display by % the "colormap('gray')" command % % See also IMWRITE, IMREAD, IMAGE, COLORMAP. dot = max(find(filename == '.')); suffix = filename(dot+1:dot+3); if strcmp(suffix,'pgm') | strcmp(suffix,'raw') % disp(sprintf('\nopens %s file\n',filename)); fp = fopen(filename,'rb','b'); % "Big-endian" byte order. if (fp<0) error(['Cannot open ' filename '.']); end if strcmp(suffix,'pgm') % Read and crack the header head = fread(fp,2,'uchar'); % pgm magic number : P5 if ~strcmp(head,'P5'), % fprintf(1,'\n Magic Number : %s\n',head); else % fprintf(1,'\n Bad Magic Number : %s\n',head); error('cannot continue this way, good bye cruel world'); end c = fread(fp,1,'uchar'); %reads the carriage return separating P5 from the creator precreator = fread(fp,1,'uchar'); % look for a '#' character preceeding a creator signature if precreator == '#', c = setstr(20); % any character except carriage return cr = setstr(10); % defines a carriage return while c ~= cr, c = fread(fp,1,'uchar'); creator = [creator,c]; end; % fprintf(1,'\n creator : %s\n',creator); else % fprintf('\n No creator signature\n'); fseek(fp,-1,'cof'); % return one char before end; end if nargin <2, if strcmp(suffix,'raw') % assume image size is 256x256 % disp('RAW file without size : assume image size is 256x256'); n = 256; m = 256; else % for PGM files % reads the size and depth % disp(' reads sizes'); n = fscanf(fp,'%d',1); tn = num2str(n); % disp([' xsize = ' tn]); m = fscanf(fp,'%d',1); tm = num2str(m); % disp([' ysize = ' tm]); p = fscanf(fp,'%d',1); tp = num2str(p); % disp([' depth = ' tp]); c = fread(fp,1,'uchar'); %reads the last carriage return end; end % Creates a gray palette and scale it to [0,1]. % disp(' create gray palette'); for i=1:256, map(i,[1:3])=[i/256,i/256,i/256]; end; % Read the image % disp(' Reads image data ...'); [X,l] = fread(fp,[n,m],'uchar'); if l ~= m*n, l, error('HSI image file is wrong length'), end % Image elements are colormap indices, so start at 1. X = X'+1; fclose(fp); % disp('end'); else error('Image file name must end in ''raw'' or ''pgm''.') end