201 research outputs found
CNN-based Real-time Dense Face Reconstruction with Inverse-rendered Photo-realistic Face Images
With the powerfulness of convolution neural networks (CNN), CNN based face
reconstruction has recently shown promising performance in reconstructing
detailed face shape from 2D face images. The success of CNN-based methods
relies on a large number of labeled data. The state-of-the-art synthesizes such
data using a coarse morphable face model, which however has difficulty to
generate detailed photo-realistic images of faces (with wrinkles). This paper
presents a novel face data generation method. Specifically, we render a large
number of photo-realistic face images with different attributes based on
inverse rendering. Furthermore, we construct a fine-detailed face image dataset
by transferring different scales of details from one image to another. We also
construct a large number of video-type adjacent frame pairs by simulating the
distribution of real video data. With these nicely constructed datasets, we
propose a coarse-to-fine learning framework consisting of three convolutional
networks. The networks are trained for real-time detailed 3D face
reconstruction from monocular video as well as from a single image. Extensive
experimental results demonstrate that our framework can produce high-quality
reconstruction but with much less computation time compared to the
state-of-the-art. Moreover, our method is robust to pose, expression and
lighting due to the diversity of data.Comment: Accepted by IEEE Transactions on Pattern Analysis and Machine
Intelligence, 201
Applying Opponent Modeling for Automatic bidding in Online Repeated Auctions
Online auction scenarios, such as bidding searches on advertising platforms,
often require bidders to participate repeatedly in auctions for the same or
similar items. We design an algorithm for adaptive automatic bidding in
repeated auctions in which the seller and other bidders also update their
strategies. We apply and improve the opponent modeling algorithm to allow
bidders to learn optimal bidding strategies in this multiagent reinforcement
learning environment. The algorithm uses almost no private information about
the opponent or restrictions on the strategy space, so it can be extended to
multiple scenarios. Our algorithm improves the utility compared to both static
bidding strategies and dynamic learning strategies. We hope the application of
opponent modeling in auctions will promote the research of automatic bidding
strategies in online auctions and the design of non-incentive compatible
auction mechanisms
Polystyrene-b-poly(oligo(ethylene oxide) monomethyl ether methacrylate)-bpolystyrene triblock copolymers as potential carriers for hydrophobic drugs
A simple and effective method is introduced to synthesize a series of polystyrene-b-poly(oligo(ethylene oxide) monomethyl ether methacrylate)-b- polystyrene (PSt-b-POEOMA-b-PSt) triblock copolymers. The structures of PSt-b-POEOMA-b-PSt copolymers were characterized by Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (1H NMR) spectroscopy. The molecular weight and molecular weight distribution of the copolymer were measured by gel permeation chromatography (GPC). Furthermore£ the self-assembling and drug-loaded behaviours of three different ratios of PSt-b-POEOMA-b-PSt were studied. These copolymers could readily self-assemble into micelles in aqueous solution. The vitamin E-loaded copolymer micelles were produced by the dialysis method. The micelle size and core-shell structure of the block copolymer micelles and the drug-loaded micelles were confirmed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The thermal properties of the copolymer micelles before and after drug-loaded were investigated by different scanning calorimetry (DSC). The results show that the micelle size is slightly increased with increasing the content of hydrophobic segments and the micelles are still core-shell spherical structures after drug-loaded. Moreover, the glass transition temperature (Tg) of polystyrene is reduced after the drug loaded. The drug loading content (DLC) of the copolymer micelles is 70%-80% by ultraviolet (UV) photolithography analysis. These properties indicate the micelles self-assembled from PSt-b- POEOMA-b- PSt copolymers would have potential as carriers for the encapsulation of hydrophobic drugs
Lightweight Photometric Stereo for Facial Details Recovery
Recently, 3D face reconstruction from a single image has achieved great
success with the help of deep learning and shape prior knowledge, but they
often fail to produce accurate geometry details. On the other hand, photometric
stereo methods can recover reliable geometry details, but require dense inputs
and need to solve a complex optimization problem. In this paper, we present a
lightweight strategy that only requires sparse inputs or even a single image to
recover high-fidelity face shapes with images captured under near-field lights.
To this end, we construct a dataset containing 84 different subjects with 29
expressions under 3 different lights. Data augmentation is applied to enrich
the data in terms of diversity in identity, lighting, expression, etc. With
this constructed dataset, we propose a novel neural network specially designed
for photometric stereo based 3D face reconstruction. Extensive experiments and
comparisons demonstrate that our method can generate high-quality
reconstruction results with one to three facial images captured under
near-field lights. Our full framework is available at
https://github.com/Juyong/FacePSNet.Comment: Accepted to CVPR2020. The source code is available
https://github.com/Juyong/FacePSNe
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