-root/
  |__lib/                             (lib for inverted indexing)
     |__crop.py                       (crop the original images)
     |__foodimageinfo.py              (getting data from yelp)
     |__imagefileinfo.py              (getting data from ayahoo_test_images)
     |__sample_generator.py           (sample generator)
     |__tfidf.py                      (implementation of tf-idf)
     |__vq.py                         (Functions for creating bag of words)