Mathematical Models and Procedures for the 
Geometric Restitution of Remote Sensing Imagery 
  
by 
Gottfried Konecny 
Institute of Photogrammetry, 
Technical University Hannover, 
Federal Republic of Germany 
Invited Paper 
Commission III 
Working Group Report III - 1 : 
"Geometry of Remote Sensing" 
XIII. Congress of the International Society 
for Photogrammetry, 
Helsinki, Finland, July 1976 
1. Working Group Activities of WG III - 1 
  
("Geometry of Remote Sensing") 
  
The Working Group III - 1 on the Geometry of remote Sensing was established following the 1972 
ISP Congress on the initiative of a few specialists who had investigated the subject in the 
preceding congress periods / 20, 37, 42, 45, 57, 59, 62, 82, 88/. There appeared to be a need 
in the investigation of non-classical remote sensing images such as the line scanner and the 
side looking radar which had been declassified in the 1960's for civilian use. Since 1972 the 
multispectral scanner also found its principal use in the Landsat (E.K.T.S.) earth resources 
satellite system /16, 80/. 
During the first meeting of the WG during the 1974 ASP meeting in St. Louis the investigation 
of the mapping capabilities of the sidelooking radar were considered to be of primary importance 
in view of the large radar mapping efforts in South America. Therefore a radar test block of 
the area around Phoenix, Arizona, flown by Goodyear Aerospace Corporation was distributed to 
WG members, who were to evaluet its accuracy by their procedures. 
The second WG meeting which covered 2 sessions of the Commission III Symposium 1974 in Stutt- 
gart preliminary results of this test were presented /24, 46/; they are being supplemented 
by new results at the 1976 ISP Congress /27, 66, 67/. Already in Stuttgart it was felt, how- 
ever that radar, even though it was primarily a mapping tool, was one, but not the most 
important remote sensing system in need of investigation. Satellite line scanner images were 
being widely used in thematic mapping; there was also an increasing interest in multispectral 
line scanning from airborne platforms for thematic purposes. There was a need to bring the 
various sensor images flown at different times to a common geometric base in order to relate 
the information to maps or to permit change detection by various image processing techniques. 
The sensors used, the scope of the applications attemted, the instrumentation and the analysis 
tools available and the interests of the various research and development groups engaged in 
solving the overall restitution (of which geometry is only a small part) are so diverging, 
that the function of the working group had to be fundamentally changed. In view of rapid de- 
velopments inside and outside the field of photogrammetry concerning remote sensing the WG 
could not consider it useful any longer to engage in common projects, but to act as a catalyst 
in discussing methodological development and in inviting groups engaged in the solution of