Nicola Dall'Asen

selected publications

1. ICCV

   Object-aware Gaze Target Detection

   Francesco Tonini, Nicola Dall’Asen, Cigdem Beyan, and Elisa Ricci

   In International Conference on Computer Vision (ICCV) 2023

   Abs arXiv Bib PDF Code

   Gaze target detection aims to predict the image location where the person is looking and the probability that a gaze is out of the scene. Several works have tackled this task by regressing a gaze heatmap centered on the gaze location, however, they overlooked decoding the relationship between the people and the gazed objects. This paper proposes a Transformer-based architecture that automatically detects objects (including heads) in the scene to build associations between every head and the gazed-head/object, resulting in a comprehensive, explainable gaze analysis composed of: gaze target area, gaze pixel point, the class and the image location of the gazed-object. Upon evaluation of the in-the-wild benchmarks, our method achieves state-of-the-art results on all metrics (up to 2.91% gain in AUC, 50% reduction in gaze distance, and 9% gain in out-of-frame average precision) for gaze target detection and 11-13% improvement in average precision for the classification and the localization of the gazed-objects.

   @inproceedings{tonini2023object,
     abbr = {ICCV},
     bibtex_show = {true},
     title = {Object-aware Gaze Target Detection},
     author = {Tonini, Francesco and Dall'Asen, Nicola and Beyan, Cigdem and Ricci, Elisa},
     booktitle = {International Conference on Computer Vision (ICCV)},
     year = {2023},
     pdf = {tonini_iccv2023.pdf},
     selected = {true},
     arxiv = {2307.09662},
     code = {https://github.com/francescotonini/object-aware-gaze-target-detection}
   }

2. ICIAP

   Unsupervised Video Anomaly Detection with Diffusion Models Conditioned on Compact Motion Representations

   *Anil Osman Tur, *Nicola Dall’Asen, Cigdem Beyan, and Elisa Ricci

   In 22nd International Conference on Image analysis and Processing (ICIAP) 2023

   Abs arXiv Bib PDF Code

   This paper aims to address the unsupervised video anomaly detection (VAD) problem, which involves classifying each frame in a video as normal or abnormal, without any access to labels. To accomplish this, the proposed method employs conditional diffusion models, where the input data is the spatiotemporal features extracted from a pre-trained network, and the condition is the features extracted from compact motion representations that summarize a given video segment in terms of its motion and appearance. Our method utilizes a data-driven threshold and considers a high reconstruction error as an indicator of anomalous events. This study is the first to utilize compact motion representations for VAD and the experiments conducted on two large-scale VAD benchmarks demonstrate that they supply relevant information to the diffusion model, and consequently improve VAD performances \textitw.r.t the prior art. Importantly, our method exhibits better generalization performance across different datasets, notably outperforming both the state-of-the-art and baseline methods.

   @inproceedings{tur2023compact,
     abbr = {ICIAP},
     bibtex_show = {true},
     title = {Unsupervised Video Anomaly Detection with Diffusion Models Conditioned on Compact Motion Representations},
     author = {Tur, *Anil Osman and Dall'Asen, *Nicola and Beyan, Cigdem and Ricci, Elisa},
     booktitle = {22nd International Conference on Image analysis and Processing (ICIAP)},
     year = {2023},
     pdf = {star_representation.pdf},
     selected = {true},
     arxiv = {2307.01533},
     code = {https://github.com/AnilOsmanTur/conditioned_video_anomaly_diffusion}
   }

3. ICIAP

   Graph-based Generative Face Anonymisation with Pose Preservation

   Nicola Dall’Asen, Yiming Wang, Hao Tang, Luca Zanella, and Elisa Ricci

   In 21st International Conference on Image analysis and Processing (ICIAP) 2022

   Abs arXiv Bib PDF Code

   We propose AnonyGAN, a GAN-based solution for face anonymisation which replaces the visual information corresponding to a source identity with a condition identity provided as any single image. With the goal to maintain the geometric attributes of the source face, i.e., the facial pose and expression, and to promote more natural face generation, we propose to exploit a Bipartite Graph to explicitly model the relations between the facial landmarks of the source identity and the ones of the condition identity through a deep model. We further propose a landmark attention model to relax the manual selection of facial landmarks, allowing the network to weight the landmarks for the best visual naturalness and pose preservation. Finally, to facilitate the appearance learning, we propose a hybrid training strategy to address the challenge caused by the lack of direct pixel-level supervision. We evaluate our method and its variants on two public datasets, CelebA and LFW, in terms of visual naturalness, facial pose preservation and of its impacts on face detection and re-identification. We prove that AnonyGAN significantly outperforms the state-of-the-art methods in terms of visual naturalness, face detection and pose preservation.

   @inproceedings{dallasen2021graphbased,
     abbr = {ICIAP},
     bibtex_show = {true},
     title = {Graph-based Generative Face Anonymisation with Pose Preservation},
     author = {Dall'Asen, Nicola and {Yiming Wang} and {Hao Tang} and {Luca Zanella} and {Elisa Ricci}},
     booktitle = {21st International Conference on Image analysis and Processing (ICIAP)},
     year = {2022},
     pdf = {2112.05496.pdf},
     selected = {true},
     arxiv = {2112.05496},
     code = {https://github.com/Fodark/anonygan}
   }