International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B3. Istanbul 2004
400
200 — MAP
—— ASTER
400
200
0
0 4000 8000
Figure 10. Cross sections of the DEMs (east-west and north-
south)
3. CONCLUSIONS
Aster provides a simple and effective method of DEM
generation. The percentage of success is very large, due to the
simultaneous acquisition of stereo data. The success of
automatic stereo-matching is only limited in uniform areas such
as water surfaces. However, in those cases editing is very
simple.
DEM production is possible in remote areas that require
medium scale topographic mapping. The typical vertical
accuracy around 10 meters can easily be achieved using
standard software packages.
However, these packages require relatively large numbers of
GCPs, in order to obtain properly geo-referenced DEMs. This
may be a limitation due to the difficulty in GCP acquisition. A
better use would be possible from position and attitude data
provided with images. These data provides a very good a priori
geo-location of images, with errors of few tens of meters.
Simplifications in the sensor model for image orientation may
be possible, requiring less ground control and keeping the same
accuracy standards in DEM geo-referencing.
References from Journals:
Gugan, D. and I. Dowman, 1988. Topographic mapping from
SPOT imagery. Photogrammetric Engineering and Remote
Sensing, 54 (10): 1409-1414.
Hirano, A., R. Welch, H. Lang, 2003. Mapping from ASTER
stereo image data: DEM validation and accuracy assessment.
ISPRS Journal of Photogrammetry and Remote Sensing,
57(2003), pp. 356-370.
Kratky, V., 1989. On-line aspects of stereophotogrammetric
processing of SPOT images. Photogrammetric Engineering and
Remote Sensing, 55(3): 311-316.
Toutin, T., Cheng, P, 2001. DEM Generation with ASTER
Stereo Data. Earth Observation Magazine, June 2001.
Westin, T., 1990. “Precision rectification of SPOT imagery”.
Photogrammetric Engineering and Remote Sensing, 56(2): 247-
253.
References from Other Literature:
Dial, G., J. Grodecki, 2002. Block adjustment with rational
polynomial camera models. ACSM-ASPRS 2002 Annual
Conference Proceedings. Washington, D.C., USA, April 19-26
2002.
ERSDAC, 2001. ASTER user guide — Level 1 Data Products
Version 3.1. Earth Remote Sensing Data Analysis Centre.
PCI, 2000. OrthoEngine V7.0 — User Manual.
Spotimage, 2002. Spot Satellite Geometry Handbook
(document S-NT-73-12-SI), Spotimage, 15-01-2002.
Toutin, 1994. Multisource data integration with an integrated
and unified image geometric modelling. Sensors and
environmental applications (Proceedings of the 14th EARSel
Symposium). 33 (2): 500-504.
Acknowledgements
The ASTER images were provided by the Japanese Space
Agency. The control DEM was provided by the "Instituto
Geográfico do Exército", of the Portuguese Army.
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