28,087 research outputs found
Action Search: Spotting Actions in Videos and Its Application to Temporal Action Localization
State-of-the-art temporal action detectors inefficiently search the entire
video for specific actions. Despite the encouraging progress these methods
achieve, it is crucial to design automated approaches that only explore parts
of the video which are the most relevant to the actions being searched for. To
address this need, we propose the new problem of action spotting in video,
which we define as finding a specific action in a video while observing a small
portion of that video. Inspired by the observation that humans are extremely
efficient and accurate in spotting and finding action instances in video, we
propose Action Search, a novel Recurrent Neural Network approach that mimics
the way humans spot actions. Moreover, to address the absence of data recording
the behavior of human annotators, we put forward the Human Searches dataset,
which compiles the search sequences employed by human annotators spotting
actions in the AVA and THUMOS14 datasets. We consider temporal action
localization as an application of the action spotting problem. Experiments on
the THUMOS14 dataset reveal that our model is not only able to explore the
video efficiently (observing on average 17.3% of the video) but it also
accurately finds human activities with 30.8% mAP.Comment: Accepted to ECCV 201
Recommended from our members
A low-bandgap dimeric porphyrin molecule for 10% efficiency solar cells with small photon energy loss
Dimeric porphyrin molecules have great potential as donor materials for high performance bulk heterojunction organic solar cells (OSCs). Recently reported dimeric porphyrins bridged by ethynylenes showed power conversion efficiencies (PCEs) of more than 8%. In this study, we design and synthesize a new conjugated dimeric D-A porphyrin ZnP2BT-RH, in which the two porphyrin units are linked by an electron accepting benzothiadiazole (BT) unit. The introduction of the BT unit enhances the electron delocalization, resulting in a lower highest occupied molecular orbital (HOMO) energy level and an increased molar extinction coefficient in the near-infrared (NIR) region. The bulk heterojunction solar cells with ZnP2BT-RH as the donor material exhibit a high PCE of up to 10% with a low energy loss (Eloss) of only 0.56 eV. The 10% PCE is the highest for porphyrin-based OSCs with a conventional structure, and this Eloss is also the smallest among those reported for small molecule-based OSCs with a PCE higher than 10% to date
Recommended from our members
A Palette of Deepened Emotions: Exploring Emotional Challenge in Virtual Reality Games
Recent work introduced the notion of ‘emotional challenge’promising for understanding more unique and diverse player experiences (PX). Although emotional challenge has immediately attracted HCI researchers’ attention, the concept has not been experimentally explored, especially in virtual reality (VR), one of the latest gaming environments. We conducted two experiments to investigate how emotional challenge affects PX when separately from or jointly with conventional challenge in VR and PC conditions. We found that relatively exclusive emotional challenge induced a wider range of different emotions in both conditions, while the adding of emotional challenge broadened emotional responses only in VR. In both experiments, VR significantly enhanced the measured PX of emotional responses, appreciation, immersion and presence. Our findings indicate that VR may be an ideal medium to present emotional challenge and also extend the understanding of emotional (and conventional) challenge in video games
- …