1. ImageNet | Please see https://image-net.org/update-mar-11-2021.php.
2. NUS-WIDE | Please see https://lms.comp.nus.edu.sg/wp-content/uploads/2019/research/nuswide/NUS-WIDE.html.
3. Caltech-256 | Please see http://www.vision.caltech.edu/Image_Datasets/Caltech256/.
4. MIRFLICKR-25000 | Please see https://press.liacs.nl/mirflickr/.
5. Corel | Please see https://sites.google.com/site/dctresearch/Home/content-based-image-retrieval.
6. Caltech-101 | Please see https://data.caltech.edu/records/mzrjq-6wc02.
7. Oxford5k | Please see https://www.robots.ox.ac.uk/~vgg/data/oxbuildings/.