function I = imreadbw(file) % IMREADBW  Reads an image as gray-scale%   I=IMREADBW(FILE) reads the image FILE and converts the result to a%   gray scale image (with DOUBLE storage class anr range normalized%   in [0,1]).% AUTORIGHTS% Copyright (c) 2006 The Regents of the University of California.% All Rights Reserved.% % Created by Andrea Vedaldi% UCLA Vision Lab - Department of Computer Science% % Permission to use, copy, modify, and distribute this software and its% documentation for educational, research and non-profit purposes,% without fee, and without a written agreement is hereby granted,% provided that the above copyright notice, this paragraph and the% following three paragraphs appear in all copies.% % This software program and documentation are copyrighted by The Regents% of the University of California. The software program and% documentation are supplied "as is", without any accompanying services% from The Regents. The Regents does not warrant that the operation of% the program will be uninterrupted or error-free. The end-user% understands that the program was developed for research purposes and% is advised not to rely exclusively on the program for any reason.% % This software embodies a method for which the following patent has% been issued: "Method and apparatus for identifying scale invariant% features in an image and use of same for locating an object in an% image," David G. Lowe, US Patent 6,711,293 (March 23,% 2004). Provisional application filed March 8, 1999. Asignee: The% University of British Columbia.% % IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY% FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES,% INCLUDING LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND% ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF CALIFORNIA HAS BEEN% ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. THE UNIVERSITY OF% CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT% LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR% A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS"% BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATIONS TO PROVIDE% MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.I=im2double(imread(file)) ;if(size(I,3) > 1)  I = rgb2gray( I ) ;end