EN FR
EN FR
STARS - 2019
Overall Objectives
New Software and Platforms
Bilateral Contracts and Grants with Industry
Bibliography
Overall Objectives
New Software and Platforms
Bilateral Contracts and Grants with Industry
Bibliography


Section: New Results

Self-Attention Temporal Convolutional Network for Long-Term Daily Living Activity Detection

Participants : Rui Dai, François Brémond.

This year, we proposed a Self-Attention - Temporal Convolutional Network (SA-TCN), which is able to capture both complex activity patterns and their dependencies within long-term untrimmed videos [34]. This attention block can also embed with other TCN-nased models. We evaluate our proposed model on DAily Home LIfe Activity Dataset (DAHLIA) and Breakfast datasets. Our proposed method achieves state-of-the-art performance on both datasets.

Work Flow

Given an untrimmed video, we represent each non-overlapping snippet by a visual encoding over 64 frames. This visual encoding is the input to the encoder-TCN, which is the combination of the following operations: 1D temporal convolution, batch normalization, ReLu, and max pooling. Next, we send the output of the encoder-TCN into the self-attention block to capture long-range dependencies. After that, the decoder-TCN applies the 1D convolution and up sampling to recover a feature map of the same dimension as visual encoding. Finally, the output will be sent to a fully connected layer with softmax activation to get the prediction. Fig 18 and 19 provide the structure of our model.

Figure 18. Overview. The model contains mainly three parts: (1) visual encoding, (2) encoder-decoder structure, (3) attention block
IMG/over_view.png
Figure 19. Attention block. This figure presents the structure of attention block
IMG/attention_block1711.png

Result

We evaluated the proposed method on two daily-living activity datasets (DAHLIA, Breakfast) and achieved state-of-the-art performances. We compared with these following State-of the arts: DOHT, Negin et al., GRU , ED-TCN, TCFPN.

Table 2. Activity detection results on DAHLIA dataset with the average of view 1, 2 and 3. * marked methods have not been tested on DAHLIA in their original paper.
Model FA1 F-score IoU mAP
DOHT 0.803 0.777 0.650 -
GRU* 0.759 0.484 0.428 0.654
ED-TCN* 0.851 0.695 0.625 0.826
Negin et al. 0.847 0.797 0.723 -
TCFPN* 0.910 0.799 0.738 0.879
SA-TCN 0.921 0.788 0.740 0.862
Table 3. Activity detection results on Breakfast dataset.
Model FA1 F-Score IoU mAP
GRU 0.368 0.295 0.198 0.380
ED-TCN 0.461 0.462 0.348 0.478
TCFPN 0.519 0.453 0.362 0.466
SA-TCN 0.497 0.494 0.385 0.480
Table 4. Average precision of ED-TCN on DAHLIA.
Activities Background House work Working Cooking
AP 0.36 0.65 0.95 0.96
Activities Laying table Eating Clearing table Wash dishes
AP 0.90 0.97 0.80 0.97
Table 5. Combination of attention block with other TCN-based model: TCFPN. (Evaluated on DAHLIA dataset)
Model FA1 F-score IoU mAP
TCFPN 0.910 0.799 0.738 0.879
SA-TCFPN 0.917 0.799 0.748 0.894
Figure 20. Detection visualization. The detection visualization of video 'S01A2K1' in DAHLIA: (1) ground truth, (2) GRU, (3) ED-TCN, (4) TCFPN and (5) SA-TCN.
IMG/visulization_n.png