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What are the advantages of using an autoencoder to build a set of filters versus a prebuilt set of gabor filters in relation to CNNs?

I'm working on a convolutional neural network and I've found various methods of building filters to convolve the image with. What are the advantages and disadvantages of each?

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carboncomputed Avatar asked Dec 06 '14 20:12

carboncomputed


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Why do we need an autoencoder?

That's a lot of data, processing time, hyperparameter tuning, and model validation before you even start building the real model. An autoencoder learns to efficiently represent a manifold on which the training data lies.

What are the drawbacks of the autoencoder algorithm?

Another drawback is you may eliminate the important information in the input data. The autoencoder algorithm requires an objective function for evaluating the accuracy of encoded/decoded input data. In most applications it’s not possible to represent the true objective, and some simple proxy like sum-of-squared-errors is used.

Do I need to train an autoencoder for feature extraction?

You have to train an autoencoder. That's a lot of data, processing time, hyperparameter tuning, and model validation before you even start building the real model. An autoencoder learns to efficiently represent a manifold on which the training data lies. If your training data is n Autoencoders can be great for feature extraction.

Why is the auto-encoder a bottleneck?

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1 Answers

Using autoencoders may in some cases improve performance, yield biologically plausible filters, and more importantly, give you a model based on your data instead of predefined filters. Autoencoders will give you filters that may fit your data better, in general. The only downside is of course the additional computation time. However, in many cases it doesn't hinder you from learning online.

For more evaluations you might have a look at: http://www.idsia.ch/~masci/papers/2011_icann.pdf

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runDOSrun Avatar answered Sep 29 '22 05:09

runDOSrun