verification and editing is here to stay, especially in difficult
terrain and at large scales. Digital ortho-images are being
produced routinely on a daily basis and are being inte-
grated into geographic information systems (GIS). There is
a need especially for large scale applications to use true
ortho-images, i.e. to correct for effects from 3D topo-
graphic objects.
Semi-automatic extraction of GIS and CAD (computer
aided design) data is still mostly restricted to research and
development. Implemented algorithms combine computer
vision approaches with rigorous photogrammetric model-
ling. Some results indicate that future systems will be
equipped with more powerful tools. The human-computer
interface is increasingly being seen as an important factor.
In practice, GIS and CAD data are often still acquired from
film imagery using analytical plotters. The term ‘semi-auto-
matic' is interpreted in at least two different ways: it is used
to mean (1) post-editing of automatically generated
results, and (2) a close interrelationship between human
operator and computer in the actual data acquisition
phase. Clarification of the term is needed.
Photogrammetric and remote sensing imagery play a sig-
nificant role in spatial data base revision. As compared to
map revision, there are many more attribute data to be
acquired. The research arena is starting to develop inte-
grated updating concepts, including various data sources
and automation. The workflow in practice is still highly
manual and GIS data capture often occurs from paper
plots showing the actual GIS objects, even though digital
imagery might be used for acquiring the object geometry.
Relatively little attention is being paid to data compression
and its effects on photogrammetric and remote sensing
processing. It is estimated that this topic will receive more
attention once digital cameras become available.
The major project of the WG was a multi-site test on the
"Performance of tie point extraction in automatic aerial tri-
angulation", carried out in co-operation with OEEPE. The
final report of the test was published in December 1998 in
the official OEEPE series No. 35, pp. 125-185. The WG
also initiated and edited the theme issue 'Automatic Image
Orientation' in the ISPRS Journal for Photogrammetry and
Remote Sensing, Vol. 52 No. 3, June 1997.
Progress, Achievements and Trends
Commission Il has made good progress towards its objec-
tives and these culminate in the ISPRS Congress in Am-
sterdam. The main achievements of the 4 years can be
summarised as:
- Progress towards establishing Image Transfer Stan-
dards though collaboration with OGC and ISO;
- Test on Performance of tie point extraction in auto-
matic aerial triangulation, carried out in co-operation
with OEEPE;
- Collaboration with CEOS in the areas of information sys-
tems and services, calibration and validation and IGOS;
- Promotion of technical advances in the areas of mobile
mapping and integration of photogrammetric tech-
niques with automatic processes, through workshops
and other meetings;
- Promotion of knowledge of SAR through tutorials.
It is recommended that work in all areas of commission
activity be continued and that collaboration with other
organisations be intensified. In particular, there is a need
for further study of techniques in GIS for efficient acquisi-
tion and revision of geospatial information and for an
increase in knowledge of Digital Photogrammetric Work-
stations by making available training and information on
the skills needed to select and use them.
Technical Commission Ill: Theory and Algorithms
Submitted by T. Schenk
1. Mandate of Commission III
The scientific agenda of a Commission is determined by the
resolutions and the terms of reference. These resolutions
have been translated into the following terms of reference:
- Algorithms for geometric determination and analysis of
photogrammetric data
- Feature extraction from multi-sensor, multi-resolution,
multi-temporal imagery
- Image understanding
- Integrated sensor orientation
- Image sequence analysis
- Algorithms for digital photogrammetric systems and
their GIS integration
- GIS concepts, with particular emphasis on integration
of image data
- Merging theories from remote sensing and computer
vision to interpret multi-sensor, multi-spectral and
multi-resolution imagery
- Quality control, verification and performance meas-
-
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ures of algorithms
- Theory and algorithms for synthetic aperture radar
2. Organisation of Commission lll
President: Toni Schenk
Scientific Secretary: Kim Boyer
Administrative Secretary: Ayman Habib
The position of the scientific secretary was created in order
to have a direct link with the computer vision community.
Kim Boyer is Director of the Machine and Robot Vision
Laboratory at The Ohio State University.
In order to effectively address the issues raised by the terms
of reference, the following working groups were created:
WG 1/1 Integrated Sensor Calibration and Orientation
Chair Peggy Agouris
Co-chair Ismael Colomina
Secretary Anthony Stefanidis
International Archives of Photogrammerty and Remote Sensing. Vol. XXXIII, Part A. Amsterdam 2000.