readgif.m

matlab处理图像的一些基本方法。其中有一部分mex程序需要安装编译

function [img, header, errmsg]=readGIF(fname)
%READGIF Import a gif file.
%
%               [I,H, errmsg]=READGIF(FNAME)
%
%               I is the image in grayscale multiplied by 32000
%               H if the constracted header
%               FNAME is the file name
%
%               Claudio 12 Oct. 1995

%
% Copyright (c) 1995 by Claudio Rivetti and Mark Young
% [e-mail],    [e-mail]
%


errmsg = '';
HEADER_SIZE = 2048;

if exist(fname) ~= 2
  errmsg='File not found';
  return;
end

[g, map]=gifread(fname);
g=ind2gray(g,map)*32000;

m=max(size(g,1),size(g,2));
img=zeros(m,m);
img(1:size(g,1), 1:size(g,2))=g;
clear g;

header=zeros(1,HEADER_SIZE);
header(1)=26;
header=setparameter(header, '*ALEX Header', '');
header=setparameter(header, 'File Type', 'GIF');
d=date;p=find(date=='-');
D=[time ' XX xxx ' d(p(1)+1:p(2)-1) ' ' d(1:p(1)-1) ' 19' d(p(2)+1:p(2)+2)];
header=setparameter(header, 'Date', D);
header=setparameter(header, 'Data length', HEADER_SIZE);
header=setparameter(header, 'Samps/line', size(img));
header=setparameter(header, 'Serial number', ' ');
header=setparameter(header, 'Id', 'GIF');
header=setparameter(header, 'X offset', '0 pixels');
header=setparameter(header, 'Y offset', '0 pixels');
header=setparameter(header, 'Scan size', [num2str(size(img,1)) ' pixels']);
header=setparameter(header, 'Trasform. Factor', 1/32000);
header=setparameter(header, 'Note', 'Image from a GIF file');


return