How can i calculate the hogfeature of an image?

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I have a code of hog which i am running and it is working fine. I understand almost every part of it but couldn't understand how the hogfeature which is 4680 was calculated? Someone should help me out. The images are 112 x 92 in size. Below is the code
%Load Image
faceDatabase = imageSet('ATT','recursive');
%Display Montage of faces figure;
montage(faceDatabase(1).ImageLocation); title('Images of Single Face in database s1'); figure; montage(faceDatabase(2).ImageLocation); title('Images of Single Face in database s2'); figure; montage(faceDatabase(3).ImageLocation); title('Images of Single Face in database s3'); figure; montage(faceDatabase(4).ImageLocation); title('Images of Single Face in database s4'); figure; montage(faceDatabase(5).ImageLocation); title('Images of Single Face in database s5');
%Display Query Image and Database side by side fprintf('Press Enter to select image') pause; [filename,pathname]=uigetfile({'*.png'},'Pick an image file'); galleryImage=imread([pathname,filename]);
figure; for i=1:size(faceDatabase,2) imageList(i)=faceDatabase(i).ImageLocation(5); end subplot(1,2,1);imshow(galleryImage);title('Selected Image'); subplot(1,2,2);montage(imageList);title('Database Image'); pause(0.002) diff=zeros(1,9);
%Split Database into Training and Test sets [training,test]=partition(faceDatabase,[0.8 0.2]);
%Extract and display Histogram of Oriented Gradient (HOG) features for %single face [hogFeature,visualization]=...... extractHOGFeatures(galleryImage);
figure; subplot(2,1,1);imshow(galleryImage);title('Input face'); subplot(2,1,2);plot(visualization);title('HOG Feature');
%Extract HOG Features for Training Set trainingFeatures=zeros(size(training,2)*training(1).Count,4680); featureCount=1; for i=1:size(training,2) for j=1:training(i).Count trainingFeatures(featureCount,:)=extractHOGFeatures(read(training(i),j)); trainingLabel{featureCount}=training(i).Description; featureCount=featureCount+1; end personIndex{i}=training(i).Description; end
% Create 40 class classifier using fitcecoc faceClassifier=fitcecoc(trainingFeatures,trainingLabel);
%Test Images from Test Set queryFeatures = extractHOGFeatures(galleryImage); personLabel=predict(faceClassifier,queryFeatures);
%Map back to training set to find identity booleanIndex=strcmp(personLabel,personIndex); integerIndex=find(booleanIndex); figure subplot(1,2,1);imshow(galleryImage);title('Query Face'); subplot(1,2,2);imshow(galleryImage);title('Matched Class');
The line i am talking about is this trainingFeatures=zeros(size(training,2)*training(1).Count,4680).
The Count 4680 is what i am trying to find how it was calculated.

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