Semi-Supervised Learning for Multi-Task Scene Understanding by Neural Graph Consensus


  • Marius Leordeanu University "Politehnica" of Bucharest
  • Mihai Cristian Pîrvu University "Politehnica" of Bucharest
  • Dragos Costea University "Politehnica" of Bucharest
  • Alina E Marcu University "Politehnica" of Bucharest
  • Emil Slusanschi University "Politehnica" of Bucharest
  • Rahul Sukthankar Google


Learning & Optimization for CV, Scene Analysis & Understanding, Object Detection & Categorization, Segmentation


We address the challenging problem of semi-supervised learning in the context of multiple visual interpretations of the world by finding consensus in a graph of neural networks. Each graph node is a scene interpretation layer, while each edge is a deep net that transforms one layer at one node into another from a different node. During the supervised phase edge networks are trained independently. During the next unsupervised stage edge nets are trained on the pseudo-ground truth provided by consensus among multiple paths that reach the nets' start and end nodes. These paths act as ensemble teachers for any given edge and strong consensus is used for high-confidence supervisory signal. The unsupervised learning process is repeated over several generations, in which each edge becomes a "student" and also part of different ensemble "teachers" for training other students. By optimizing such consensus between different paths, the graph reaches consistency and robustness over multiple interpretations and generations, in the face of unknown labels. We give theoretical justifications of the proposed idea and validate it on a large dataset. We show how prediction of different representations such as depth, semantic segmentation, surface normals and pose from RGB input could be effectively learned through self-supervised consensus in our graph. We also compare to state-of-the-art methods for multi-task and semi-supervised learning and show superior performance.




How to Cite

Leordeanu, M., Pîrvu, M. C., Costea, D., Marcu, A. E., Slusanschi, E., & Sukthankar, R. (2021). Semi-Supervised Learning for Multi-Task Scene Understanding by Neural Graph Consensus. Proceedings of the AAAI Conference on Artificial Intelligence, 35(3), 1882-1892. Retrieved from



AAAI Technical Track on Computer Vision II