We study training of Convolutional Neural Networks (CNNs) with ReLU activations and introduce exact convex optimization formulations with a polynomial complexity with respect to the number of data samples, the number of neurons, and data dimension. More specifically, we develop a convex analytic framework utilizing semi-infinite duality to obtain equivalent convex optimization problems for several two- and three-layer CNN architectures. We first prove that two-layer CNNs can be globally optimized via an `2 norm regularized convex program. We then show that multi-layer circular CNN training problems with a single ReLU layer are equivalent to an `1 regularized convex program that encourages sparsity in the spectral domain. We also extend these results to three-layer CNNs with two ReLU layers. Furthermore, we present extensions of our approach to different pooling methods, which elucidates the implicit architectural bias as convex regularizers.
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An automated approach for improving the inference latency and energy efficiency of pretrained CNNs by removing irrelevant pixels with focused convolutions
Computer vision often uses highly accurate Convolutional Neural Networks (CNNs), but these deep learning models are associated with ever-increasing energy and computation requirements. Producing more energy-efficient CNNs often requires model training which can be cost-prohibitive. We propose a novel, automated method to make a pretrained CNN more energyefficient without re-training. Given a pretrained CNN, we insert a threshold layer that filters activations from the preceding layers to identify regions of the image that are irrelevant, i.e. can be ignored by the following layers while maintaining accuracy. Our modified focused convolution operation saves inference latency (by up to 25%) and energy costs (by up to 22%) on various popular pretrained CNNs, with little to no loss in accuracy
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- PAR ID:
- 10514487
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- Asia and South Pacific Design Automation Conference (ASP-DAC)
- ISSN:
- 2153-6961
- ISBN:
- 979-8-3503-9354-5
- Page Range / eLocation ID:
- 890 to 895
- Format(s):
- Medium: X
- Location:
- Incheon, Korea, Republic of
- Sponsoring Org:
- National Science Foundation
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