José Guerrero

Lorenzo Mur-Labadia, Jose J. Guerrero, Ruben Martinez-Cantin

Accurate affordance detection and segmentation with pixel precision is an important piece in many complex systems based on interactions, such as robots and assitive devices. We present a new approach to affordance perception which enables accurate multi-label segmentation. Our approach can be used to automatically extract grounded affordances from first person videos of interactions using a 3D map of the environment providing pixel level precision for the affordance location. We use this method to build the largest and most complete dataset on affordances based on the EPIC-Kitchen dataset, EPIC-Aff, which provides interaction-grounded, multi-label, metric and spatial affordance annotations. Then, we propose a new approach to affordance segmentation based on multi-label detection which enables multiple affordances to co-exists in the same space, for example if they are associated with the same object. We present several strategies of multi-label detection using several segmentation architectures. The experimental results highlight the importance of the multi-label detection. Finally, we show how our metric representation can be exploited for build a map of interaction hotspots in spatial action-centric zones and use that representation to perform a task-oriented navigation.

Maria Santos-Villafranca, Dustin Carrión-Ojeda, Alejandro Perez-Yus et al.

Existing methods for egocentric action recognition often rely solely on RGB videos, while additional modalities, e.g., audio, can improve accuracy in challenging scenarios. However, most prior multimodal approaches assume all modalities are available at inference, leading to significant accuracy drops, or even failure, when inputs are missing. To address this, we introduce KARMMA, a multimodal Knowledge distillation approach for egocentric Action Recognition robust to Missing ModAlities that requires no modality alignment across all samples during training or inference. KARMMA distills knowledge from a multimodal teacher into a multimodal student that benefits from all available modalities while remaining robust to missing ones, making it suitable for diverse multimodal scenarios without retraining. Our student uses approximately 50% fewer computational resources than our teacher, resulting in a lightweight and fast model. Experiments on Epic-Kitchens and Something-Something show that our student achieves competitive accuracy while significantly reducing accuracy drops under missing modality conditions.

Melani Sanchez-Garcia, Ruben Martinez-Cantin, Jose J. Guerrero

Prosthetic vision is being applied to partially recover the retinal stimulation of visually impaired people. However, the phosphenic images produced by the implants have very limited information bandwidth due to the poor resolution and lack of color or contrast. The ability of object recognition and scene understanding in real environments is severely restricted for prosthetic users. Computer vision can play a key role to overcome the limitations and to optimize the visual information in the simulated prosthetic vision, improving the amount of information that is presented. We present a new approach to build a schematic representation of indoor environments for phosphene images. The proposed method combines a variety of convolutional neural networks for extracting and conveying relevant information about the scene such as structural informative edges of the environment and silhouettes of segmented objects. Experiments were conducted with normal sighted subjects with a Simulated Prosthetic Vision system. The results show good accuracy for object recognition and room identification tasks for indoor scenes using the proposed approach, compared to other image processing methods.