function triangulate_image

img = imread ( 'filter2dkl.pgm' );
[ N, M ] = size ( img );
h = 1 / ( N - 1 );

np = N * M; % number of points

TI = zeros ( np, 1 );
TI ( : ) = img;

TX = zeros ( np, 1 );
TY = zeros ( np, 1 );

% compute points
k = 1;
for i = 1 : M
    for j = 1 : N
        TX ( k ) = ( i - 1 ) * h;
        TY ( k ) = ( j - 1 ) * h;
        k = k + 1;
    end
end

nt = 2 * ( N - 1 ) * ( M - 1 ); %number of triangles

TT = zeros ( nt, 3 );

% compute triangles
k = 1;
for i = 1 : M - 1
    for j = 1 : N - 1
        t = ( i - 1 ) * N + j;
        TT ( k, : ) = [ ( t + N ) ( t ) ( t + 1 ) ] ;
        TT ( k + 1, : ) = [ ( t + 1 ) ( t + N + 1 ) ( t + N ) ] ;
        k = k + 2;
    end
end