19,966 research outputs found
Channel-Recurrent Autoencoding for Image Modeling
Despite recent successes in synthesizing faces and bedrooms, existing
generative models struggle to capture more complex image types, potentially due
to the oversimplification of their latent space constructions. To tackle this
issue, building on Variational Autoencoders (VAEs), we integrate recurrent
connections across channels to both inference and generation steps, allowing
the high-level features to be captured in global-to-local, coarse-to-fine
manners. Combined with adversarial loss, our channel-recurrent VAE-GAN
(crVAE-GAN) outperforms VAE-GAN in generating a diverse spectrum of high
resolution images while maintaining the same level of computational efficacy.
Our model produces interpretable and expressive latent representations to
benefit downstream tasks such as image completion. Moreover, we propose two
novel regularizations, namely the KL objective weighting scheme over time steps
and mutual information maximization between transformed latent variables and
the outputs, to enhance the training.Comment: Code: https://github.com/WendyShang/crVAE. Supplementary Materials:
http://www-personal.umich.edu/~shangw/wacv18_supplementary_material.pd
Pruning artificial neural networks: a way to find well-generalizing, high-entropy sharp minima
Recently, a race towards the simplification of deep networks has begun,
showing that it is effectively possible to reduce the size of these models with
minimal or no performance loss. However, there is a general lack in
understanding why these pruning strategies are effective. In this work, we are
going to compare and analyze pruned solutions with two different pruning
approaches, one-shot and gradual, showing the higher effectiveness of the
latter. In particular, we find that gradual pruning allows access to narrow,
well-generalizing minima, which are typically ignored when using one-shot
approaches. In this work we also propose PSP-entropy, a measure to understand
how a given neuron correlates to some specific learned classes. Interestingly,
we observe that the features extracted by iteratively-pruned models are less
correlated to specific classes, potentially making these models a better fit in
transfer learning approaches
Architectural perspectives in the cathedral of Palermo : image-based modeling for cultural heritage understanding and enhancement
Palermo off ers a repertoire of both artistic
and architectural solid perspective of great beauty and
in large quantity. This paper addresses the problem of
the 3D survey of these works and their related study
through the use of image-based modelling (IBM) techniques.
We propose, as case studies, the use of IBM
techniques inside the Cathedral of Palermo. Indeed, the
church houses a huge and rich sculptural repertoire, dating
back to 16th century, which constitutes a valid field
of IBM techniques application.
The aim of this study is to demonstrate the e ffectiveness
and potentiality of these techniques for geometric
analysis of sculptured works. Indeed, usually the survey
of these artworks is very diffi cult due the geometric complexity,
typical of sculptured elements. In this study,
we analysed cylindrical and planar geometries as well as
carrying out an application of perspective return.peer-reviewe
MVPNet: Multi-View Point Regression Networks for 3D Object Reconstruction from A Single Image
In this paper, we address the problem of reconstructing an object's surface
from a single image using generative networks. First, we represent a 3D surface
with an aggregation of dense point clouds from multiple views. Each point cloud
is embedded in a regular 2D grid aligned on an image plane of a viewpoint,
making the point cloud convolution-favored and ordered so as to fit into deep
network architectures. The point clouds can be easily triangulated by
exploiting connectivities of the 2D grids to form mesh-based surfaces. Second,
we propose an encoder-decoder network that generates such kind of multiple
view-dependent point clouds from a single image by regressing their 3D
coordinates and visibilities. We also introduce a novel geometric loss that is
able to interpret discrepancy over 3D surfaces as opposed to 2D projective
planes, resorting to the surface discretization on the constructed meshes. We
demonstrate that the multi-view point regression network outperforms
state-of-the-art methods with a significant improvement on challenging
datasets.Comment: 8 pages; accepted by AAAI 201
Preferred instantaneous vacuum for linear scalar fields in cosmological space-times
We discuss the problem of defining a preferred vacuum state at a given time
for a quantized scalar field in Friedmann, Lema\^itre, Robertson Walker (FLRW)
space-time. Among the infinitely many homogeneous, isotropic vacua available in
the theory, we show that there exists at most one for which every Fourier mode
makes vanishing contribution to the adiabatically renormalized energy-momentum
tensor at any given instant. For massive fields such a state exists in the most
commonly used backgrounds in cosmology, and provides a natural candidate for
the ground state at that instant of time. The extension to the massless and the
conformally coupled case are also discussed.Comment: 19 pages, 4 figures. Section VI was expanded to include a discussion
on semi-classical gravity. Version to appear in PR
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