U-Net-Id, an Instance Segmentation Model for Building Extraction from Satellite Images—Case Study in the Joanópolis City, Brazil

Currently, there exists a growing demand for individual building mapping in regions of rapid urban growth in less-developed countries. Most existing methods can segment buildings but cannot discriminate adjacent buildings. Here, we present a new convolutional neural network architecture (CNN) called...

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Main Authors: Fabien H. Wagner, Ricardo Dalagnol, Yuliya Tarabalka, Tassiana Y. F. Segantine, Rogério Thomé, Mayumi C. M. Hirye
Format: Article
Language:English
Published: MDPI AG 2020-05-01
Series:Remote Sensing
Subjects:
Online Access:https://www.mdpi.com/2072-4292/12/10/1544
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author Fabien H. Wagner
Ricardo Dalagnol
Yuliya Tarabalka
Tassiana Y. F. Segantine
Rogério Thomé
Mayumi C. M. Hirye
author_facet Fabien H. Wagner
Ricardo Dalagnol
Yuliya Tarabalka
Tassiana Y. F. Segantine
Rogério Thomé
Mayumi C. M. Hirye
author_sort Fabien H. Wagner
collection DOAJ
description Currently, there exists a growing demand for individual building mapping in regions of rapid urban growth in less-developed countries. Most existing methods can segment buildings but cannot discriminate adjacent buildings. Here, we present a new convolutional neural network architecture (CNN) called U-net-id that performs building instance segmentation. The proposed network is trained with WorldView-3 satellite RGB images (0.3 m) and three different labeled masks. The first is the building mask; the second is the border mask, which is the border of the building segment with 4 pixels added outside and 3 pixels inside; and the third is the inner segment mask, which is the segment of the building diminished by 2 pixels. The architecture consists of three parallel paths, one for each mask, all starting with a U-net model. To accurately capture the overlap between the masks, all activation layers of the U-nets are copied and concatenated on each path and sent to two additional convolutional layers before the output activation layers. The method was tested with a dataset of 7563 manually delineated individual buildings of the city of Joanópolis-SP, Brazil. On this dataset, the semantic segmentation showed an overall accuracy of 97.67% and an F1-Score of 0.937 and the building individual instance segmentation showed good performance with a mean intersection over union (IoU) of 0.582 (median IoU = 0.694).
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spelling doaj.art-949a457aa76b4bc580b801bc9c3a87832023-11-20T00:13:59ZengMDPI AGRemote Sensing2072-42922020-05-011210154410.3390/rs12101544U-Net-Id, an Instance Segmentation Model for Building Extraction from Satellite Images—Case Study in the Joanópolis City, BrazilFabien H. Wagner0Ricardo Dalagnol1Yuliya Tarabalka2Tassiana Y. F. Segantine3Rogério Thomé4Mayumi C. M. Hirye5GeoProcessing Division, Foundation for Science, Technology and Space Applications—FUNCATE, São José dos Campos, SP 12210-131, BrazilRemote Sensing Division, National Institute for Space Research—INPE, São José dos Campos, SP 12227-010, BrazilLuxcarta Technology, Parc d’Activité l’Argile, Lot 119b, 06370 Mouans Sartoux, FranceGeoProcessing Division, Foundation for Science, Technology and Space Applications—FUNCATE, São José dos Campos, SP 12210-131, BrazilGeoProcessing Division, Foundation for Science, Technology and Space Applications—FUNCATE, São José dos Campos, SP 12210-131, BrazilQuapá Lab, Faculty of Architecture and Urbanism, University of São Paulo—USP, São Paulo, SP 05508-900, BrazilCurrently, there exists a growing demand for individual building mapping in regions of rapid urban growth in less-developed countries. Most existing methods can segment buildings but cannot discriminate adjacent buildings. Here, we present a new convolutional neural network architecture (CNN) called U-net-id that performs building instance segmentation. The proposed network is trained with WorldView-3 satellite RGB images (0.3 m) and three different labeled masks. The first is the building mask; the second is the border mask, which is the border of the building segment with 4 pixels added outside and 3 pixels inside; and the third is the inner segment mask, which is the segment of the building diminished by 2 pixels. The architecture consists of three parallel paths, one for each mask, all starting with a U-net model. To accurately capture the overlap between the masks, all activation layers of the U-nets are copied and concatenated on each path and sent to two additional convolutional layers before the output activation layers. The method was tested with a dataset of 7563 manually delineated individual buildings of the city of Joanópolis-SP, Brazil. On this dataset, the semantic segmentation showed an overall accuracy of 97.67% and an F1-Score of 0.937 and the building individual instance segmentation showed good performance with a mean intersection over union (IoU) of 0.582 (median IoU = 0.694).https://www.mdpi.com/2072-4292/12/10/1544instance segmentationU-netbuilding detectionurban landscape
spellingShingle Fabien H. Wagner
Ricardo Dalagnol
Yuliya Tarabalka
Tassiana Y. F. Segantine
Rogério Thomé
Mayumi C. M. Hirye
U-Net-Id, an Instance Segmentation Model for Building Extraction from Satellite Images—Case Study in the Joanópolis City, Brazil
Remote Sensing
instance segmentation
U-net
building detection
urban landscape
title U-Net-Id, an Instance Segmentation Model for Building Extraction from Satellite Images—Case Study in the Joanópolis City, Brazil
title_full U-Net-Id, an Instance Segmentation Model for Building Extraction from Satellite Images—Case Study in the Joanópolis City, Brazil
title_fullStr U-Net-Id, an Instance Segmentation Model for Building Extraction from Satellite Images—Case Study in the Joanópolis City, Brazil
title_full_unstemmed U-Net-Id, an Instance Segmentation Model for Building Extraction from Satellite Images—Case Study in the Joanópolis City, Brazil
title_short U-Net-Id, an Instance Segmentation Model for Building Extraction from Satellite Images—Case Study in the Joanópolis City, Brazil
title_sort u net id an instance segmentation model for building extraction from satellite images case study in the joanopolis city brazil
topic instance segmentation
U-net
building detection
urban landscape
url https://www.mdpi.com/2072-4292/12/10/1544
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