We introduce an unsupervised feature learning algorithm that is trained explicitly with k-means for simple cells and a form of agglomerative clustering for complex cells. When trained on a large dataset of YouTube frames, the algorithm automatically discovers semantic concepts, such as faces.
![](https://www.derinogrenme.com/wp-content/uploads/2015/07/Emergence-of-Object-Selective-Features-in-Unsupervised-Feature-Learning.png)