TY - CONF AU - M. Campos-Taberner AU - Adriana Romero AU - Carlo Gatta AU - Gustavo Camps-Valls A2 - IGARSS PY - 2015// TI - Shared feature representations of LiDAR and optical images: Trading sparsity for semantic discrimination BT - IEEE International Geoscience and Remote Sensing Symposium IGARSS2015 SP - 4169 EP - 4172 N2 - This paper studies the level of complementary information conveyed by extremely high resolution LiDAR and optical images. We pursue this goal following an indirect approach via unsupervised spatial-spectral feature extraction. We used a recently presented unsupervised convolutional neural network trained to enforce both population and lifetime spar-sity in the feature representation. We derived independent and joint feature representations, and analyzed the sparsity scores and the discriminative power. Interestingly, the obtained results revealed that the RGB+LiDAR representation is no longer sparse, and the derived basis functions merge color and elevation yielding a set of more expressive colored edge filters. The joint feature representation is also more discriminative when used for clustering and topological data visualization. UR - http://ieeexplore.ieee.org/xpl/mostRecentIssue.jsp?punumber=7303999 UR - http://dx.doi.org/10.1109/IGARSS.2015.7326744 N1 - LAMP; 600.079;MILAB ID - M. Campos-Taberner2015 ER -