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© Springer International Publishing AG 2017
R. Díaz-Delgado et al. (eds.), The Roles of Remote Sensing in Nature Conservation,
DOI 10.1007/978-3-319-64332-8_3
Pre-processing of Remotely Sensed Imagery
Peter Bunting
Abstract A common obstacle to the use of remote sensing data for nature conservation is the difficulty in obtaining or generating data that are pre-processed to a
standard that gives confidence in their subsequent use. Such processing is essential
in order to facilitate physical measurement (e.g., of temperature, surface reflectance,
height) and compare data (e.g., reflectance or radar backscatter) acquired for different dates or areas. For optical and radar data, this pre-processing includes orthorectification, calibration, atmospheric and topographic correction and, in the case of
LiDAR, ground return classification and surface height retrieval. This chapter
therefore provides an overview of the common pre-processing steps that are undertaken or needed in order to create what has been recently termed an analysis ready
data (ARD) product. Increasingly, such products are being provided routinely to
minimize the effort of data users but knowledge of how this is achieved is important
in determining the integrity and understanding the use of the data. The information
provided should help users to identify, select and use data with confidence or to
perform their own processing of the raw data.
Keywords Earth observation • Optical • Radar • Lidar • Preprocessing • Atmosphere
• Topography • Geometric correction
Introduction
Pre-processing of all remotely sensed imagery, whether airborne or spaceborne, first
involves a geometric correction, with this ensuring accurate spatial location of datasets on the Earth’s surface (Lillesand et al. 2004). Standardization to a scientific unit
is then undertaken such that the data are comparable to that acquired from the same
or different sensors (Analysis Ready Data; ARD), with this including calibration of
optical data to radiometric units and atmospheric correction to units of reflectance,
transformation of Synthetic Aperture Radar (SAR) data to backscatter and other
P. Bunting (*)
Earth Observation and Ecosystem Dynamics Group, Department of Geography
and Earth Sciences, Aberystwyth University, Aberystwyth SY23 3DB, UK
e-mail: pfb@aber.ac.uk
© Springer International Publishing AG 2017
R. Díaz-Delgado et al. (eds.), The Roles of Remote Sensing in Nature Conservation,
DOI 10.1007/978-3-319-64332-8_3
Pre-processing of Remotely Sensed Imagery
Peter Bunting
Abstract A common obstacle to the use of remote sensing data for nature conservation is the difficulty in obtaining or generating data that are pre-processed to a
standard that gives confidence in their subsequent use. Such processing is essential
in order to facilitate physical measurement (e.g., of temperature, surface reflectance,
height) and compare data (e.g., reflectance or radar backscatter) acquired for different dates or areas. For optical and radar data, this pre-processing includes orthorectification, calibration, atmospheric and topographic correction and, in the case of
LiDAR, ground return classification and surface height retrieval. This chapter
therefore provides an overview of the common pre-processing steps that are undertaken or needed in order to create what has been recently termed an analysis ready
data (ARD) product. Increasingly, such products are being provided routinely to
minimize the effort of data users but knowledge of how this is achieved is important
in determining the integrity and understanding the use of the data. The information
provided should help users to identify, select and use data with confidence or to
perform their own processing of the raw data.
Keywords Earth observation • Optical • Radar • Lidar • Preprocessing • Atmosphere
• Topography • Geometric correction
Introduction
Pre-processing of all remotely sensed imagery, whether airborne or spaceborne, first
involves a geometric correction, with this ensuring accurate spatial location of datasets on the Earth’s surface (Lillesand et al. 2004). Standardization to a scientific unit
is then undertaken such that the data are comparable to that acquired from the same
or different sensors (Analysis Ready Data; ARD), with this including calibration of
optical data to radiometric units and atmospheric correction to units of reflectance,
transformation of Synthetic Aperture Radar (SAR) data to backscatter and other
P. Bunting (*)
Earth Observation and Ecosystem Dynamics Group, Department of Geography
and Earth Sciences, Aberystwyth University, Aberystwyth SY23 3DB, UK
e-mail: pfb@aber.ac.uk