% Version 0.1, Feb 2006.
% This code is copyrighted by Ashutosh Saxena, Stanford University
% It is available for non-commercial use only. For commericial use, please
% contact the authors.
% Any publication or report resulting from Use of this code, should cite:
% Learning Depth from Single Monocular Images, Ashutosh Saxena, Sung H. Chung, Andrew Y. Ng, NIPS 2005.
% 3-D Depth Reconstruction from a Single Still Image, Ashutosh Saxena, Sung H. Chung, Andrew Y. Ng, To appear in IJCV 2007.
% For more info and dataset, visit: http://ai.stanford.edu/~asaxena/learningdepth/
% For a better version of the algorithm, also visit: 
% http://ai.stanford.edu/~asaxena/reconstruction3d/


L3 = [1 2 1];
E3 = [-1 0 1];
S3 = [-1 2 -1];
    %L5 = [1 2 3 2 1];       %can be improved
    %L7 = [1 2 3 4 3 2 1];   % can be improved
    gMask = gaussMask(4,1.4);
    
    %Navatia Babu filters oriented at six angles (0,30,60,90,120,150)
    NB1 = [ -100, -100, 0, 100, 100; ...
            -100, -100, 0, 100, 100; ...
            -100, -100, 0, 100, 100; ...
            -100, -100, 0, 100, 100; ...
            -100, -100, 0, 100, 100];
    NB2 = [ -100, 32, 100, 100, 100; ...
            -100,-78, 92,  100, 100; ...
            -100,-100, 0,  100, 100; ...
            -100,-100,-92, 78,  100; ...
            -100,-100,-100,-32, 100];
    NB3 = -NB2';
    NB4 = -NB1';
    NB5 = -NB3(end:-1:1,:);
    NB6 = NB5'; 
    
    M_LL = L3'*L3;
    M_LE = L3'*E3;
    
backgroundGray = zeros(9,9);    
backgroundGray(3:7,3:7) = NB1;

subplot(1,15,10);   imagesc(backgroundGray);    colormap gray;  axis off; axis square;
subplot(1,15,11);   imagesc(backgroundGray);    colormap gray;  axis off; axis square;