974 research outputs found
Identifying First-person Camera Wearers in Third-person Videos
We consider scenarios in which we wish to perform joint scene understanding,
object tracking, activity recognition, and other tasks in environments in which
multiple people are wearing body-worn cameras while a third-person static
camera also captures the scene. To do this, we need to establish person-level
correspondences across first- and third-person videos, which is challenging
because the camera wearer is not visible from his/her own egocentric video,
preventing the use of direct feature matching. In this paper, we propose a new
semi-Siamese Convolutional Neural Network architecture to address this novel
challenge. We formulate the problem as learning a joint embedding space for
first- and third-person videos that considers both spatial- and motion-domain
cues. A new triplet loss function is designed to minimize the distance between
correct first- and third-person matches while maximizing the distance between
incorrect ones. This end-to-end approach performs significantly better than
several baselines, in part by learning the first- and third-person features
optimized for matching jointly with the distance measure itself
Co-interest Person Detection from Multiple Wearable Camera Videos
Wearable cameras, such as Google Glass and Go Pro, enable video data
collection over larger areas and from different views. In this paper, we tackle
a new problem of locating the co-interest person (CIP), i.e., the one who draws
attention from most camera wearers, from temporally synchronized videos taken
by multiple wearable cameras. Our basic idea is to exploit the motion patterns
of people and use them to correlate the persons across different videos,
instead of performing appearance-based matching as in traditional video
co-segmentation/localization. This way, we can identify CIP even if a group of
people with similar appearance are present in the view. More specifically, we
detect a set of persons on each frame as the candidates of the CIP and then
build a Conditional Random Field (CRF) model to select the one with consistent
motion patterns in different videos and high spacial-temporal consistency in
each video. We collect three sets of wearable-camera videos for testing the
proposed algorithm. All the involved people have similar appearances in the
collected videos and the experiments demonstrate the effectiveness of the
proposed algorithm.Comment: ICCV 201
Towards Egocentric Person Re-identification and Social Pattern Analysis
Wearable cameras capture a first-person view of the daily activities of the
camera wearer, offering a visual diary of the user behaviour. Detection of the
appearance of people the camera user interacts with for social interactions
analysis is of high interest. Generally speaking, social events, lifestyle and
health are highly correlated, but there is a lack of tools to monitor and
analyse them. We consider that egocentric vision provides a tool to obtain
information and understand users social interactions. We propose a model that
enables us to evaluate and visualize social traits obtained by analysing social
interactions appearance within egocentric photostreams. Given sets of
egocentric images, we detect the appearance of faces within the days of the
camera wearer, and rely on clustering algorithms to group their feature
descriptors in order to re-identify persons. Recurrence of detected faces
within photostreams allows us to shape an idea of the social pattern of
behaviour of the user. We validated our model over several weeks recorded by
different camera wearers. Our findings indicate that social profiles are
potentially useful for social behaviour interpretation
Egocentric Vision-based Future Vehicle Localization for Intelligent Driving Assistance Systems
Predicting the future location of vehicles is essential for safety-critical
applications such as advanced driver assistance systems (ADAS) and autonomous
driving. This paper introduces a novel approach to simultaneously predict both
the location and scale of target vehicles in the first-person (egocentric) view
of an ego-vehicle. We present a multi-stream recurrent neural network (RNN)
encoder-decoder model that separately captures both object location and scale
and pixel-level observations for future vehicle localization. We show that
incorporating dense optical flow improves prediction results significantly
since it captures information about motion as well as appearance change. We
also find that explicitly modeling future motion of the ego-vehicle improves
the prediction accuracy, which could be especially beneficial in intelligent
and automated vehicles that have motion planning capability. To evaluate the
performance of our approach, we present a new dataset of first-person videos
collected from a variety of scenarios at road intersections, which are
particularly challenging moments for prediction because vehicle trajectories
are diverse and dynamic.Comment: To appear on ICRA 201
Summarizing First-Person Videos from Third Persons' Points of Views
Video highlight or summarization is among interesting topics in computer
vision, which benefits a variety of applications like viewing, searching, or
storage. However, most existing studies rely on training data of third-person
videos, which cannot easily generalize to highlight the first-person ones. With
the goal of deriving an effective model to summarize first-person videos, we
propose a novel deep neural network architecture for describing and
discriminating vital spatiotemporal information across videos with different
points of view. Our proposed model is realized in a semi-supervised setting, in
which fully annotated third-person videos, unlabeled first-person videos, and a
small number of annotated first-person ones are presented during training. In
our experiments, qualitative and quantitative evaluations on both benchmarks
and our collected first-person video datasets are presented.Comment: 16+10 pages, ECCV 201
- …