Image Processing Reference
Basic knowledge about the differences between multispectral and hyperspectral
data is provided by Patrick Hostert in Chapter 9, where the potential of hyperspec-
tral image analysis is distinguished. He presents relevant pre-processing steps and
different ways to analyze hyperspectral data. Moreover, relevant analysis approaches
are explained including material detection techniques, spectral angle mapping, or
spectral mixture analysis, to name some. The chapter closes with a short outlook on
expected developments with relevance for urban applications.
Chapter 10, written by Elisabeth Schöpfer, Stefan Lang and Josef Strobl, focuses
on segmentation of remotely sensed image data and object-based image analysis of
urban areas. It also discusses the differences between the two different approaches
'pixel-based' and 'object-based' image analysis. They explain the main concepts of
object-based image analysis: to work on homogeneous image objects rather than on
single pixels and to use spectral and spatial information while merging pixels into
homogeneous groups (image objects, segments). The chapter depicts very briefly
urban applications by means of two case studies.
Thierry Ranchin's and Lucien Wald's Chapter 11 concentrates on techniques
related to image and data from different sources with varying spatial and spectral
resolutions. It presents and discusses some of the technical issues that influence
data fusion in the urban context . Several fusion cases studies are discussed here to
illustrate the potential of data fusion techniques. The authors emphasize on the
importance of the diversity of data fusion. The few examples provided cannot fully
describe its complexity and this field is still a strong and active research in urban
remote sensing and the other civilian domains.
A case study from Phoenix, Arizona is depicted by William L. Stefanov and
Maik Netzband in Chapter 12. They examine the relationships between ecological
variables and landscape structure in cities. These relationships are assessed using
ASTER and MODIS data; and through the techniques of expert system land cover
classification and grid-based landscape metric analysis. The authors argue that this
multi-scale approach is of great use to urban ecologists and spatial planners, as
landscape structural analysis and measures of ecosystem function provide monitoring
tools for regional habitat and climatic alteration associated with urbanization.
Furthermore, the applied uniform spatial reference systems provided by remotely
sensed data permit quantitative evaluation in comparative studies regarding the
spatial configuration of existing developed and open spaces.
Chapter 13 by Mohamed Ait Belaid focuses on remote sensing (RS) of desert
cities , within the context of developing countries. The characteristics of urban areas
in the desert environment are described, and the potential of satellite imageries is
discussed, how they are used to map and monitor changes in these areas over space
and time. Urban and sub-urban landscapes of desert cities are shaped by various
factors such as desertification, economic development, and wars and conflicts. In
their chapter the authors include photo-interpretation techniques assisted by com-
puter techniques to produce the classified imagery maps of land use categories and
the comparison of the classified land use changes in urban areas.
In Chapter 14 Andy Kwarteng and Christopher Small give an overview over
urbanization and the urban environment connected to urban vegetation, surface