Auto-Encoders to classify images?

Question

I am currently a student and I am developing a project of a Neural Network to classify a dataset of images. Since this images are not labeled I would need a unsupervised method of learning. It has been suggested to me I should use Auto-Encoders, is it possible to use an Auto-Encoder to 'discover' important features and then use the features learnt in the 'Hidden Layer' into a Multilayer Perceptron Network for instance, so I can classify images? Thank you all for your help.

Answer 1

Classification is inherently a supervised problem. To do this, you would need to have labeled images that the classifier can learn to predict. Your problem sounds like clustering. Here, you'd assign images to discrete categories (clusters) based on some notion of similarity; images assigned to the same cluster are more similar to each other than those assigned to different clusters. Many clustering algorithms are available. If you wanted, you could perform clustering on the hidden layer representations of an autoencoder. You could think of this as clustering the images after mapping them nonlinearly into a feature space.