1. Automated retrieval of forest structure variables based on multi-scale texture analysis of VHR satellite imagery
- Author
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Dominique Guyon, Samia Boukir, Nesrine Chehata, Benoit Beguet, Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Université Sciences et Technologies - Bordeaux 1, Géoressources et environnement, and Institut Polytechnique de Bordeaux (Bordeaux INP)-Université Bordeaux Montaigne
- Subjects
010504 meteorology & atmospheric sciences ,multi-scale ,Computer science ,[SDE.MCG]Environmental Sciences/Global Changes ,Feature vector ,Multispectral image ,0211 other engineering and technologies ,Feature selection ,02 engineering and technology ,01 natural sciences ,feature selection ,multi-resolution ,Satellite imagery ,Computers in Earth Sciences ,Engineering (miscellaneous) ,Spatial analysis ,ComputingMilieux_MISCELLANEOUS ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences ,Remote sensing ,multiple regression ,forestry ,Pléiades ,Quickbird ,Statistical model ,15. Life on land ,Atomic and Molecular Physics, and Optics ,Computer Science Applications ,Panchromatic film ,Tree (data structure) ,texture ,[SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing - Abstract
The main goal of this study is to design a method to describe the structure of forest stands from Very High Resolution satellite imagery, relying on some typical variables such as crown diameter, tree height, trunk diameter, tree density and tree spacing. The emphasis is placed on the automatization of the process of identification of the most relevant image features for the forest structure retrieval task, exploiting both spectral and spatial information. Our approach is based on linear regressions between the forest structure variables to be estimated and various spectral and Haralick’s texture features. The main drawback of this well-known texture representation is the underlying parameters which are extremely difficult to set due to the spatial complexity of the forest structure. To tackle this major issue, an automated feature selection process is proposed which is based on statistical modeling, exploring a wide range of parameter values. It provides texture measures of diverse spatial parameters hence implicitly inducing a multi-scale texture analysis. A new feature selection technique, we called Random PRiF, is proposed. It relies on random sampling in feature space, carefully addresses the multicollinearity issue in multiple-linear regression while ensuring accurate prediction of forest variables. Our automated forest variable estimation scheme was tested on Quickbird and Pleiades panchromatic and multispectral images, acquired at different periods on the maritime pine stands of two sites in South-Western France. It outperforms two well-established variable subset selection techniques. It has been successfully applied to identify the best texture features in modeling the five considered forest structure variables. The RMSE of all predicted forest variables is improved by combining multispectral and panchromatic texture features, with various parameterizations, highlighting the potential of a multi-resolution approach for retrieving forest structure variables from VHR satellite images. Thus an average prediction error of ∼ 1.1 m is expected on crown diameter, ∼ 0.9 m on tree spacing, ∼ 3 m on height and ∼ 0.06 m on diameter at breast height.
- Published
- 2014