how to sum the number of objects in different images in Matlab? - matlab

Question

this is my entire code. What i did here is to try to find matching points between an image and a template i substracted from the image.
The first loop and second loop extract all the card from the original image(first image with set of card)
The next part of the code is just finding the matching point between extracted card and the template.
The last for loop i created, is based on range of the matching points count I selected to discard cards that have less matching with the template.(selectCard)
Then I created the for loop to (selectCard) and I applied connected components to count the objects remaining on the card when They pass the selection criteria.
So I need to get the total number of object of all the card that pass the selection criteria I have made. Basically, I got a result of each card. Not all the card. I need to compute the result of All those cards.
for j=1:max(max(LabeledImage))
[row, col] = find(LabeledImage==j);
len=max(row)-min(row)+2;
breadth=max(col)-min(col)+2;
Img=uint8(zeros([len breadth 3] ));
sy=min(col)-1;
sx=min(row)-1;
for i=1:size(row,1)
x=row(i,1)-sx;
y=col(i,1)-sy;
Img(x,y,:)=grayImage(row(i,1),col(i,1),:);
end
mytitle=strcat('Card Number:',num2str(j));
% figure,imshow(Img);title(mytitle);
Img=rgb2gray(Img);
pointsForSpade1 = detectHarrisFeatures(Img);
pointsForSpade2 = detectHarrisFeatures(Template_for_spade);
%extract neighborhood features
[featuresForSpade1,valid_pointsForSpade1] =
extractFeatures(Img,pointsForSpade1);
[featuresForSpade2,valid_pointsForSpade2] =
extractFeatures(Template_for_spade,pointsForSpade2);
%Match the features
indexPairs = matchFeatures(featuresForSpade1,featuresForSpade2);
%retrieve the locations of the corresponding points for each image.
matchedPointsForSpade1 = valid_pointsForSpade1(indexPairs(:,1),:);
matchedPointsForSpade2 = valid_pointsForSpade2(indexPairs(:,2),:);
% visualize the corresponding points.
figure,subplot(5,5,j)
showMatchedFeatures(Img,Template_for_spade,matchedPointsForSpade1,.....
matchedPointsForSpade2, 'montage');
count1 = matchedPointsForSpade1.Count;
%disp(matchedPoints1);
selectCard4 = find(count1>10);
Total = 0;
for e4= 1: selectCard4
figure, subplot(5,5,j)
showMatchedFeatures(Img(e4),Template_for_spade,matchedPointsForSpade1,...
matchedPointsForSpade2, 'montage');
title(Name);
% eliminate not needed hole on the card.
level = 0.57;
Img2 = imbinarize(Img, level);
%Morphological operation
ImgComp = imcomplement(Img2);
se = strel('disk', 10);
Iopened = imopen(ImgComp, se);
%figure;
%imshow(Iopened);
[Label3, numObject4] = bwlabel(Iopened);
TotalSpade = sum(numObject4);
s = sprintf('\n card number: of this set has #%s spades',j,
num2str(TotalSpade));
disp(s);
end
end
I want to display the sum of connected objects based on selected card.
Thank you.

Answer 1

There are three main problems here. First, you initialize Total = 0; and then change the variable name to TotalSpade. Change the initialization to:
TotalSpade = 0;
Second, the assignment to TotalSpade is overwriting the previous value. In order to accumulate the total, you need to add to TotalSpade instead. Also, numObject4 is a scalar, so sum doesn't do anything.
TotalSpade = TotalSpade + numObject4;
Finally, if you only want to print the total of the objects, you need to take your print statement outside the loop. You can also use fprintf instead of sprintf+disp since fprintf prints to the console if you don't specify a file descriptor.
for e4 = 1:selectCard4
...
end
fprintf('\n card number: of this set has #%s spades', j,
num2str(TotalSpade));