I am using HOG for feature extraction that consist 1×n vector features. I have to print all training image feature into one text file in matrix form. I have tried write matlab code. Can anyone help me?

objects={'apple','bat','beetle'}; trimgs=10;

for i=1:length(objects) for j=1:trimgs imgpath=['.\images\' objects{i} '\img (' int2str(j) ').gif'];

        I=imread(imgpath);
        J = imresize(I,[256,256]);
        fid=fopen('feature_vector.txt','a');
        fprintf(fid,'%i\t',hog_feature_vector(J));
        fprintf(fid,'\n');
        fclose(fid);

    end
end

%this code print feature vector in the text file. but not matrix form.

[Image Analyst]

hog_feature_vector is a 1-d vector. How do you want it to be in a matrix? Like, how many rows and columns, and why?

Also, read this: http://www.mathworks.com/matlabcentral/answers/13205#answer_18099

[bamini thavarajah]

• I want to classify image using HOG feature.
• I have 10 classes, 20 images per class, for training I have selected 10 images per class(100 images).
• I resized images to 256×256
• I need 100×34596 size matrix.
• row indicates images, column indicates HOG features
• I have to lable the matrix with class no in the last column.