Matlab error: Index in position 2 exceeds array bounds (must not exceed 737). Error in FinalLaser (line 57) test_imb=i​magebb(tes​t_xmin-x_d​isp_max:te​st_xmax+x_​disp_max, test_ymin-​y_disp_max​:test_ymax​+y_disp_ma​x);

I am new to MATLAB, can anybody help me solve this error for code:

clear all;

clc;

close all;

imagea = imread('00020361.bmp');

imageb = imread('00020362.bmp');

%[xmax, ymax]=size(imageaa);

imageaa = imcrop(imagea,[100 100 736 736]);

imagebb = imcrop(imageb,[100 100 736 736]);

% Windows Size

wsize=[32,32];

w_width=wsize(1);

w_height=wsize(2);

% Center point grid

xmin=w_width/2;

ymin=w_height/2;

xgrid=100:w_width/2:736;

ygrid=100:w_height/2:736;

% Number of windows in total

w_xcount=length(xgrid);

w_ycount=length(ygrid);

% These correspond to the ranges for search windows in image b

x_disp_max=w_width/2;

y_disp_max=w_height/2;

% For every window, first we have to create the test matrix

% in image a. Then in image B, we have to correlate this test window

% around its originak position in image a, the range is

% predetermined. The point of max correlation corresponds to the final avg

% displacement of that window

test_ima(w_width, w_height)=0;

test_imb(w_width+2*x_disp_max, w_height+2*y_disp_max)=0;

dpx(w_xcount, w_ycount)=0;

dpy(w_xcount, w_ycount)=0;

xpeak1=0;

ypeak1=0;

% i, j are for the windows

% test_i and test_j are for the test window to be

% extracted from imaga aa

for i=1:(w_xcount)

for j=1:(w_ycount)

max_correlation=0;

test_xmin=xgrid(i)-w_width/2;

test_xmax=xgrid(i)+w_width/2;

test_ymin=ygrid(j)-w_height/2;

test_ymax=ygrid(j)+w_height/2;

x_disp=0;

y_disp=0;

test_ima=imageaa(test_xmin:test_xmax, test_ymin:test_ymax);

test_imb=imagebb(test_xmin-x_disp_max:test_xmax+x_disp_max, test_ymin-y_disp_max:test_ymax+y_disp_max);

correlation=normxcorr2(test_ima, test_imb);

[xpeak, ypeak]=find(correlation==max(correlation(:)));

% re scaling

xpeak1= test_xmin+xpeak-wsize(1)/2-x_disp_max;

ypeak1= test_ymin+ypeak-wsize(2)/2-y_disp_max;

dpx(i,j)=xpeak1-xgrid(i);

dpy(i,j)=ypeak1-ygrid(j);

end

end

% vector display

quiver(dpy,-dpx)

Answer 1

[Guru Mohanty]

Hi, it is difficult to provide an exact solution without your original data. However, when I executed your code using demo data, it is trying to access pixels which are beyond the boundary set by imcrop function. However, after modifying the grid positions, the code should work.

clear all; 
clc; 
imagea = imread('tire.tif'); 
imageb = imread('trees.tif'); 
%[xmax, ymax]=size(imageaa); 
imageaa = imcrop(imagea,[0 0 170 170]); 
imagebb = imcrop(imageb,[0 0 170 170]); 
% Windows Size 
wsize=[32,32]; 
w_width=wsize(1); 
w_height=wsize(2);  
% Center point grid 
xmin=w_width/2; 
ymin=w_height/2; 
xgrid=1+(w_width):w_width/2:170-(w_width); 
ygrid=1+(w_width):w_height/2:170-(w_width); 
% Number of windows in total 
w_xcount=length(xgrid); 
w_ycount=length(ygrid);  
% These correspond to the ranges for search windows in image b 
x_disp_max=w_width/2; 
y_disp_max=w_height/2;  
% For every window, first we have to create the test matrix 
% in image a. Then in image B, we have to correlate this test window 
% around its originak position in image a, the range is  
% predetermined. The point of max correlation corresponds to the final avg 
% displacement of that window  
test_ima(w_width, w_height)=0; 
test_imb(w_width+2*x_disp_max, w_height+2*y_disp_max)=0; 
dpx(w_xcount, w_ycount)=0; 
dpy(w_xcount, w_ycount)=0; 
xpeak1=0; 
ypeak1=0;  
% i, j are for the windows 
% test_i and test_j are for the test window to be 
% extracted from imaga aa  
for i=1:(w_xcount) 
    for j=1:(w_ycount) 
        max_correlation=0; 
        test_xmin=xgrid(i)-w_width/2; 
        test_xmax=xgrid(i)+w_width/2; 
        test_ymin=ygrid(j)-w_height/2; 
        test_ymax=ygrid(j)+w_height/2; 
        x_disp=0; 
        y_disp=0; 
        test_ima=imageaa(test_xmin:test_xmax, test_ymin:test_ymax); 
        test_imb=imagebb(test_xmin-x_disp_max:test_xmax+x_disp_max, test_ymin-y_disp_max:test_ymax+y_disp_max); 
        correlation=normxcorr2(test_ima, test_imb); 
        [xpeak, ypeak]=find(correlation==max(correlation(:)));  
        % re scaling 
        xpeak1= test_xmin+xpeak-wsize(1)/2-x_disp_max; 
        ypeak1= test_ymin+ypeak-wsize(2)/2-y_disp_max; 
        dpx(i,j)=xpeak1-xgrid(i); 
        dpy(i,j)=ypeak1-ygrid(j); 
    end 
end 
% vector display 
quiver(dpy,-dpx) 

[Vignesh Sahadevan]

Thanks a lot! If I have two diagrams like this, how can I find average correlation maps?