Z]-AEDAS: A Automatical Elevation Data Acquisition System 
Qian Zeng-Bo Wan Zhi-Long 
Dept. of Photogrammtry & Remote Sensing 
Zhengzhou Institute of Surveying & Mapping(ZISM) 
Zhengzhow Henan 450052 
P. R. CHINA 
ABSTRACT 
A automatical elevation data acquisition system 
named AEDAS is developed to generate DTM 
automatically from the aerial stereo pair on 
MASSCOMP computer in Zhengzhou Institute of 
Surveying & Mapping(ZISM). This paper describes the 
hardware configuration and software function. This 
software system can automatically or interactively 
recognize and locate fiducial marks with the CHAMFER 
matching method and finish relative orientation with 
the feature-based method or hierarchical correlation 
method. Then epipolar resample and hierarchical 
relaxation correlation are executed, that is the 
system finishes the DTM acquisition automatically. 
At last; the system gets orthphoto and completes the 
quality control. This software system was written in 
C language. 
INTRUDUCTI ON 
The use of digital or digitized imagery and VISI 
technique make possible the fast, efficient, and 
accurate automatic Digital Terrain —ModelC(DTM) 
extraction and orthphoto production by stereo 
digital correlation. However, the approach still has 
limmitation that leaves some percentage of the 
points uncollected or in error. So, it is neccessary 
of interactive editing the data. A automatic 
elevation data acquisition system named AEDAS is 
developed to generate DTM and or thphoto 
automatically from the aerial stereo pair on 
MASSCOMP computer in Zhengzhou Institute of 
Surveying & Mapping(ZISM). After describing the 
system configuration this paper addresses an 
approach to image orientation, DIM extraction, 
quality control and orthphoto production. 
THE AEDAS SYSTEM 
Hardware Configuration 
The AEDAS hardware uses a MASSCOMP computer as 
host computer. The basic configuration and 
performance of the host computer as follows: 
1 ) Two MC68030 25MHz Virtual Memory CPU (MC68882 
90MHz Floating Point Co-processor/CPU, 64 KB Cache 
Memory CPU), 3 serial ports (Console, Modem, 
270 
Printer) (may be 5CPU installed) 
2 ) 16 Mb ECC Memory 
30 Multibus slots 
11 6U VME slots 
32 RS-232 serial ports 
650 Kb Floppy Disk Drive 
two 568 MB Winchester disk (may be 9000MB) 
8 > 150 MB Cartridge Tape Drive 
9 ) Stream Tape Driver 1/2" 
10) Two Graphics Subsystem 
11) Two image monitor 
1152x910x4x2Bf) 
12) 19" color control monitor 
13) 3 buttom mouse system 
14) Printronix Line Printer 
Software Function 
The software in this system can be divided into 
five basic (fuunctional) components: 
(1) Database management; 
(2) Photogrammetry; 
(3) DIM extraction; 
(4) Quality control; 
(5) Orthphoto production; 
All the software within the system was written in 
ANSI C language. 
- ED GT a 
NON NSW 
(1152x910x12x2B{, 
FUNCTION DESCRIPTION OF THE AEDAS 
The five basic components of the AEDAS software 
function are described in detail as follows: 
Data Management 
This software allows the operator to input any 
kinds of parameters used within the system and forms 
a relational database for next steps. Each of the 
steps can track the details and add respectively 
information to the database. The major inputs to the 
AEDAS are: 
1) digital or digitized imageries and scanning 
parameter 
2) camera calibration reports 
3) flight information 
4) DTM gridding resolution 
5) name or code of the interesting area 
6) ground control points 
s - Bst bum dui 
me aab NR. m