In: Wagner W„ Szflcely, B. (eds.): ISPRS TC VII Symposium - 100 Years ISPRS, Vienna, Austria, July 5-7, 2010,1 APRS, Vol. XXXVIII, Part 7B
yields. To grant the agricultural subsidy it had to record the
cultivation data of the area too. On the basis of field works new
digital soil and nutriment supply maps were created to evaluate
agri-ecological environment. Digital elevation model with 1 m
vertical and 0.2 m horizontal RMS was produced.
In the course of the field works every stock place in the pear
genetic collection were measured by DGPS methods, where the
survey accuracy was RMS<0.2 m after the TRIMBLE
PATHFINDER compensating calculation in Geostation
environment. The height and width of trees were defined with
the help of Leica Distro 8 laser distance meter. To prepare the
hyperspectral flight we used a digital orthophoto, which was
taken in 2007 with a ground resolution of 0.5*0.5 m.
The spatial data were completed by airborne hyperspectral data,
which in general makes possible to perform botanical and
special soil investigations (Nagy et al, 2006).
Since the applied joint camera is less known in Europe and it
can also be reached as an investigation delivery, the details of
the measurement are described below.
In 2007, the first high-tech AISA DUAL airborne hyperspectral
image spectroscopy system (AIS) was installed and operated in
cooperation the University of Debrecen, AMTC, Department of
Water and Environmental Management with the Hungarian
Institute of Agricultural Engineering in Godollo-Hungary
funded by NKTH. The most important parts of the hyperspectral
sensors are the spectrograph, which dissolve the electric waves
arrived through the optical rift with the help of prisms and
optical screen. The two hyperspectral sensors are mounted and
synchronized in a common house; therefore it is known ASIA
DUAL system (Milics et al. 2010).
The two cams can perceive in the visible wavelength, near
infrared range and short wave infrared range. Technical
information of applied ASIA DUAL hyperspectral system as
follows: Push-broom hyperspectral imagery sensor with the
fibre optic radiation meters (FODIS); Miniature integrated
GPS/INS sensor, which serves the position, height and
momentary situation (pith, roll, yaw) of plane, Compact PC-
based data collector and mobile receiver unit; CaliGeo software
runs as a separate software package under the ITT ENVI
software package to do the spectral and geometrical corrections.
The parameters of the hyperspectral image: Wavelength: 400-
2450 nm (EAGLE: 400-970 nm and HAWK: 970-2450 nm);
Spectral sample taking: 1,2-10 nm; Ground resolution: 0,4-3 m
(with plane flight altitude), The photogrammetric and spectral
accuracies were evaluated by different GPS/Inertia systems in
different flight conditions in Europe (Germany, Finland,
Switzerland and Hungary) in 2008-2009.
OxTS - RT 3003 was showed pixel sized accuracy of lm
without external DGPS data while the C-MIGITS III provided
about 6m RMS position error, when the average flight altitude
was 800-1000 m and the average speed was 200-250 km/h, with
minimum swath width of 500m. Studying the navigation data it
can be determinable that the angle deflection of the flight
remains within 10 degree in case of taking image in general
climatic conditions (Table 1.). However in special
meteorological condition we also measured larger deflections
rates, which was rarely exceeded 15 %.
Angle
deflecti
on
Roll
Pitch
Yaw
(%)
sum
(%)
(%)
sum
(%)
(%)
sum
. (%)
0-2
31.2
31.2
31.5
31.5
35.8
35.8
2-4
39.6
70.8
54.0
85.6
18.6
54.4
4-6
17.1
87.9
9.3
94.9
28.3
82.7
6-8
8.1
96.0
1.9
96.8
15.6
98.4
8-10
3.9
100
3.18
100
1.58
100
Table 1. Flight parameters
The hyperspectral DUAL sensor is fixed without gyrostabilizer
in the airplane, so the deflection originating from the motion of
the airplane is corrected by CALIGEO program with the
navigation data of GPS/INS system in the course of the
geometric correction. Before the flight boresight type
calibration was carried out (Holzwarth et al., 2005).
The images of the flight campaign using in this paper were
taken in the early afternoon in cloudless condition in June 2009,
where the mean angle deflection was lower than 4%.
Before mosaicing of the images parametrical correction and
radiometrical normalization between the bands were applied
(Burai and Tamas, 2004) (Figure 1.).
Figure 1. Georectified flight strips of the hyperspectral images
and the Ujfeherto Research Station (red border lines)
The accurate geometrical correction of the hyperspectral image
taken by AISA DUAL push-broom sensor with high spatial
resolution (<1.5 m) could be achieved by OxTS RT 3003
positioning system working with two antenna. The
atmospherical correction was done on the basis of the direct
radiation measured by FODIS sensor detecting the changing of
the radiation above the sensor. We modified the effects from the
movements of the airplane with the navigation values, which is
necessary to define the FODIS ratio. The high angle deflection
values were separated from the FODIS data, which was
replaced by data generated linear interpolation.
3. RESULTS
In our investigations, the airborne imaging system was used in
fruit researches to develop a new GIS based recording system of