Polygonization of binary classification maps using mesh approximation with right angle regularity

Onur Tasar (1, 2) , Emmanuel Maggiori (1, 2) , Pierre Alliez (1, 2) , Yuliya Tarabalka (1, 2)

1 TITANE - Geometric Modeling of 3D Environments
2 COMUE UCA - COMUE Université Côte d'Azur (2015-2019)

One of the most popular and challenging tasks in remote sensing applications is the generation of digitized representations of Earth's objects from satellite raster image data. A common approach to tackle this challenge is a two-step method that first involves performing a pixel-wise classification of the raster data, then vectorizing the obtained classification map. We propose a novel approach, which recasts the polygoniza-tion problem as a mesh-based approximation of the input classification map, where binary labels are assigned to the mesh triangles to represent the building class. A dense initial mesh is decimated and optimized using local edge and vertex-based operators in order to minimize an objective function that models a balance between fidelity to the classification map in 1 norm sense, right angle regularity for polygonized buildings, and final mesh complexity. Experiments show that adding the right angle objective yields better representations quantitatively and qualitatively than previous work and commonly used polygon generalization methods in remote sensing literature for similar number of vertices.

Mots clés: Polygonization; vectorization; remote sensing; classification maps; mesh approximation; right angles

Domaines: Géométrie algorithmique [cs.CG]; Vision par ordinateur et reconnaissance de formes [cs.CV]; Apprentissage [cs.LG]; Traitement des images [eess.IV]

Onur Tasar, Emmanuel Maggiori, Pierre Alliez, Yuliya Tarabalka. Polygonization of binary classification maps using mesh approximation with right angle regularity . IEEE International Geoscience and Remote Sensing Symposium - IGARSS 2018, Jul 2018, Valencia, Spain. ⟨hal-01765155⟩