Extended backpropagation for invariant pattern recognition neural networks

This paper presents some improvements on a neural network structure composed by a multilayer perceptron (MLP) with a preprocessing neural net, in order to perform translation, rotation and scale invariant pattern recognition. The preprocessing network has been modified and backpropagation (BP) has been generalized for training the preprocessing net as well as the multilayer perceptron. The new structure and weight selection procedure lead to a more noise tolerant neural net which also performs a better pattern classification.