Title
Breaking Winner-takes-all: Iterative-winners-out Networks for Weakly Supervised Temporal Action Localization.
Abstract
We address the challenging problem of weakly supervised temporal action localization from unconstrained web videos, where only the video-level action labels are available during training. Inspired by the Adversarial Erasing strategy in weakly supervised semantic segmentation, we propose a novel iterative-winners-out network. Specifically, we make two technical contributions: 1) we propose an iterative training strategy, namely winners-out, to select the most discriminative action instances in each training iteration and remove them in the next training iteration. This iterative process alleviates the "winner-takes-all" phenomenon that existing approaches tend to choose the video segments that strongly correspond to the video label, but neglect other less discriminative video segments. With this strategy, our network is able to localize not only the most discriminative instances but also the less discriminative ones. 2) to better select the target action instances in winners-out, we devise a class-discriminative localization technique. By employing the attention mechanism and the information learned from data, our technique is able to identify the most discriminative action instances effectively. The two key components are integrated into an end-to-end network to localize actions without using the frame-level annotations. Extensive experimental results demonstrate that our method outperforms the state-of-the-art weakly supervised approaches on ActivityNet1.3 and improves mAP from 16.9% to 20.5% on THUMOS14. Notably, even with weak video-level supervision, our method attains comparable accuracy to those employing frame-level supervisions.
Year
DOI
Venue
2019
10.1109/TIP.2019.2922108
IEEE transactions on image processing : a publication of the IEEE Signal Processing Society
Keywords
Field
DocType
Videos,Training,Proposals,Image segmentation,Correlation,Object detection,Semantics
Object detection,Pattern recognition,Iterative and incremental development,Segmentation,Image segmentation,Artificial intelligence,Winner-take-all,Target–action,Discriminative model,Semantics,Mathematics
Journal
Volume
Issue
ISSN
28
12
1941-0042
Citations 
PageRank 
References 
18
0.67
12
Authors
6
Name
Order
Citations
PageRank
Runhao Zeng1293.51
Chuang Gan225331.92
Peihao Chen3292.15
Wen-bing Huang416718.91
Wu Qingyao525933.46
Mingkui Tan650138.31