4,636 research outputs found
FastDepth: Fast Monocular Depth Estimation on Embedded Systems
Depth sensing is a critical function for robotic tasks such as localization,
mapping and obstacle detection. There has been a significant and growing
interest in depth estimation from a single RGB image, due to the relatively low
cost and size of monocular cameras. However, state-of-the-art single-view depth
estimation algorithms are based on fairly complex deep neural networks that are
too slow for real-time inference on an embedded platform, for instance, mounted
on a micro aerial vehicle. In this paper, we address the problem of fast depth
estimation on embedded systems. We propose an efficient and lightweight
encoder-decoder network architecture and apply network pruning to further
reduce computational complexity and latency. In particular, we focus on the
design of a low-latency decoder. Our methodology demonstrates that it is
possible to achieve similar accuracy as prior work on depth estimation, but at
inference speeds that are an order of magnitude faster. Our proposed network,
FastDepth, runs at 178 fps on an NVIDIA Jetson TX2 GPU and at 27 fps when using
only the TX2 CPU, with active power consumption under 10 W. FastDepth achieves
close to state-of-the-art accuracy on the NYU Depth v2 dataset. To the best of
the authors' knowledge, this paper demonstrates real-time monocular depth
estimation using a deep neural network with the lowest latency and highest
throughput on an embedded platform that can be carried by a micro aerial
vehicle.Comment: Accepted for presentation at ICRA 2019. 8 pages, 6 figures, 7 table
Spatial and Angular Resolution Enhancement of Light Fields Using Convolutional Neural Networks
Light field imaging extends the traditional photography by capturing both
spatial and angular distribution of light, which enables new capabilities,
including post-capture refocusing, post-capture aperture control, and depth
estimation from a single shot. Micro-lens array (MLA) based light field cameras
offer a cost-effective approach to capture light field. A major drawback of MLA
based light field cameras is low spatial resolution, which is due to the fact
that a single image sensor is shared to capture both spatial and angular
information. In this paper, we present a learning based light field enhancement
approach. Both spatial and angular resolution of captured light field is
enhanced using convolutional neural networks. The proposed method is tested
with real light field data captured with a Lytro light field camera, clearly
demonstrating spatial and angular resolution improvement
Photometric Depth Super-Resolution
This study explores the use of photometric techniques (shape-from-shading and
uncalibrated photometric stereo) for upsampling the low-resolution depth map
from an RGB-D sensor to the higher resolution of the companion RGB image. A
single-shot variational approach is first put forward, which is effective as
long as the target's reflectance is piecewise-constant. It is then shown that
this dependency upon a specific reflectance model can be relaxed by focusing on
a specific class of objects (e.g., faces), and delegate reflectance estimation
to a deep neural network. A multi-shot strategy based on randomly varying
lighting conditions is eventually discussed. It requires no training or prior
on the reflectance, yet this comes at the price of a dedicated acquisition
setup. Both quantitative and qualitative evaluations illustrate the
effectiveness of the proposed methods on synthetic and real-world scenarios.Comment: IEEE Transactions on Pattern Analysis and Machine Intelligence
(T-PAMI), 2019. First three authors contribute equall
- …