91,273 research outputs found
Fireground location understanding by semantic linking of visual objects and building information models
This paper presents an outline for improved localization and situational awareness in fire emergency situations based on semantic technology and computer vision techniques. The novelty of our methodology lies in the semantic linking of video object recognition results from visual and thermal cameras with Building Information Models (BIM). The current limitations and possibilities of certain building information streams in the context of fire safety or fire incident management are addressed in this paper. Furthermore, our data management tools match higher-level semantic metadata descriptors of BIM and deep-learning based visual object recognition and classification networks. Based on these matches, estimations can be generated of camera, objects and event positions in the BIM model, transforming it from a static source of information into a rich, dynamic data provider. Previous work has already investigated the possibilities to link BIM and low-cost point sensors for fireground understanding, but these approaches did not take into account the benefits of video analysis and recent developments in semantics and feature learning research. Finally, the strengths of the proposed approach compared to the state-of-the-art is its (semi -)automatic workflow, generic and modular setup and multi-modal strategy, which allows to automatically create situational awareness, to improve localization and to facilitate the overall fire understanding
Detect to Track and Track to Detect
Recent approaches for high accuracy detection and tracking of object
categories in video consist of complex multistage solutions that become more
cumbersome each year. In this paper we propose a ConvNet architecture that
jointly performs detection and tracking, solving the task in a simple and
effective way. Our contributions are threefold: (i) we set up a ConvNet
architecture for simultaneous detection and tracking, using a multi-task
objective for frame-based object detection and across-frame track regression;
(ii) we introduce correlation features that represent object co-occurrences
across time to aid the ConvNet during tracking; and (iii) we link the frame
level detections based on our across-frame tracklets to produce high accuracy
detections at the video level. Our ConvNet architecture for spatiotemporal
object detection is evaluated on the large-scale ImageNet VID dataset where it
achieves state-of-the-art results. Our approach provides better single model
performance than the winning method of the last ImageNet challenge while being
conceptually much simpler. Finally, we show that by increasing the temporal
stride we can dramatically increase the tracker speed.Comment: ICCV 2017. Code and models:
https://github.com/feichtenhofer/Detect-Track Results:
https://www.robots.ox.ac.uk/~vgg/research/detect-track
Activity Driven Weakly Supervised Object Detection
Weakly supervised object detection aims at reducing the amount of supervision
required to train detection models. Such models are traditionally learned from
images/videos labelled only with the object class and not the object bounding
box. In our work, we try to leverage not only the object class labels but also
the action labels associated with the data. We show that the action depicted in
the image/video can provide strong cues about the location of the associated
object. We learn a spatial prior for the object dependent on the action (e.g.
"ball" is closer to "leg of the person" in "kicking ball"), and incorporate
this prior to simultaneously train a joint object detection and action
classification model. We conducted experiments on both video datasets and image
datasets to evaluate the performance of our weakly supervised object detection
model. Our approach outperformed the current state-of-the-art (SOTA) method by
more than 6% in mAP on the Charades video dataset.Comment: CVPR'19 camera read
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