1 st Multidisciplinary Workshop on Extracting and Classifying Urban Objects from High Resolution Image. São Paulo, 18 April 2007

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1 1 st Multidisciplinary Workshop on Extracting and Classifying Urban Objects from High Resolution Image São Paulo, 18 April 2007

2 Multiscale object-based image analysis for informal settlements detection Project: Master Plan of Paranaguá-Pr Federal University of Paraná and Municipality of Paranaguá Prof. Alzir Felippe Buffara Antunes

3 Introduction The objective is to detect informal settlements or irregular settlements from QUICKBIRDS image data using methods of object oriented image analysis (ecognition);

4 Motivation Strong urban growth is a phenomenon that occurs in Brazil since The migration of the rural population to the cities has created a shortage of dwellings causing these invasion vacant lands (private or government owned); Favelas grown as the only kind of living. In order to carry out urban planning and sustainable development urban planners need fast and adequate spatial data analysis. Mapping of informal settlements could play crucial role for urban land policy.

5 Providing security of tenure is often seen as a precondition for improving the living conditions and is a prerequisite for better natural resource management and development urban areas. In the Brazilian coast towns many of those irregular settlements are located in mangroves and swamp areas which generally are areas of permanent protection or national parks.

6 Mason, O. S. & Fraser, C. S. (1998) describe informal settlements as :... dense settlements comprising communities housed in selfconstructed shelters under conditions of informal or traditional land tenure.... They are a common feature of developing countries and are typically the product of an urgent need for shelter by the urban poor. As such they are characterised by a dense proliferation of small, makeshift shelters built from diverse materials (such as plastic, tin sheeting and wooden planks), by degradation of the local ecosystem (for example, erosion and poor water quality and sanitation) and by severe social problems...

7 Challenge : How remote sensing can give a fast answer to the urban planners? Using QUICKBIRD image data might not sufficiently feasible to detect of small houses due to the sensor s spatial resolution. Therefore with additional information gives beneficial ancillary data for land tenure policy. Case of Study: Paranaguá - PR

8 MARINGÁ LONDRINA Tropico de Capricórnio PARAGUAI FOZ DO IGUAÇU GUARAPUAVA CURITIBA ESTADO DE SÃO PAULO ARGENTINA Paranaguá Oceano

9 BAY Mangroves Informal settlements along mangroves Typical dwelling

10 ecognition tools Data Extraction Strategy Applying a stepwise refinement by: initial spectral classification using Nearest Neighbors 1 generating and describing more concrete classes using: form features textural features classification based context features described by fuzzy membership functions 2 using inheritance mechanisms and semantic grouping 3 (Thomas Blaschke,2005)

11 Classification Level 1 Level 2

12 Benefits to the municipality Land use map in a scale 1: and for Irregular areas 1: 5.000; Data base in shape file of the irregular areas; Overview of environmental and social problems and drawing of possible solution; Additional data for land tenure policy and social justice!

13 Land Use Map (Integration of Spot 5 + Classification)

14 Conclusions 1. QUICKBIRD data are well suited to detect informal settlement areas although small houses are hardly detectable. 2. Applying image enhancement methods such as the principal components analysis might be useful especially detection of small objects. 3. The final product has fulfilled the planners expectations.

15 Agradecimentos /Acknowledgments Prefeitura Municipal de Paranaguá e Equipe do Plano Diretor; Departamento de Geomática e Geografia da UFPR; Prodig, Université de Sorbonne Paris I, Image SPOT5.

16 References ANTUNES, A.F.B, STURM, U. Segmentação orientada a objeto aplicada ao monitoramento de ocupações irregulares em áreas de proteção ambiental. XII Simpósio Brasileiro de Sensoriamento Remoto. Goiânia ANTUNES, A.F.B. Object oriented analysis and semantic network for high resolution image classification. Boletim de Ciências Geodésicas. Volume 9, n 2, BAATZ, M. & SCHÄPE, A. Multiresolution segmentation an optimization approach for high quality multi-scale image segmentation; Angewandte Geographische Informationsverarbeitung XII, Edition Herbert Wichmann, Karlsruhe, p HOFMANN, P. Detecting informal settlements from ikonos image data using methods of object oriented image analysis an example from Cape Town (South Africa). definiens ag http: KARSENTY, A. Classification orientee objet de la permeabilite des sols en zones urbaines a l aide d imagerie tres haute resolution et donnees Laser Scanner a Curitiba. XYZ magazine. Editée par l association Française de Topographie. Vol.102. Março

17 University Msc, Phd Programm Undergraduation Programm