International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XXXIX-B4, 2012
XXII ISPRS Congress, 25 August — 01 September 2012, Melbourne, Australia
Projection of PSS and MSS sensors on earth surface you can see
on figure 5. Span width for PSS sensor (6 CCD matrixes) will
be 23.3 km, for MSS sensor (4 CCD matrixes) span width will
be 20.1 km
Ei MSS - IR
MSS - Red
em PSS - 1-6
pnm MSS - Green
Figure 5. Projection of PSS and MSS sensors on earth surface.
2.4. Source data modeling
For developing technology source data were obtained by
modeling sensors and shooting jf *Canopus-V" satellite
[Nekrasov,2010]. Modeling images were done with the help of
next technology [Nekrasov,2011]. High resolution image of
"Resurs-DK-1" satellite was get for whole area of experimental
testing area. Heights differens of testing area is about 400 m.
We used digital elevation model (DEM), which was processed
from SRTM (Shuttle Radar Topographic Mission) data.
Orthoimage was processed using this hi-resolution image and
DEM. GSD for orthoimage is 1 m, accuracy of external
orientation is about 2.11 m. Orthoimage and DEM used as
source data for creation of simulated images of *Canopus-V"
PSS and MSS sensors. External orientation of simulated images
is defined with the help of rational polynomial coefficients
(RPC). RPC were calculated with errors of navigation system
for simulation of real shooting conditions.
2.5. Methods, algorithms
RPC are based on next equations, connecting ground geodetic
coordinates with image coordinates:
Le Jip An hy)
gi(9y An, hy)
oo = Js Any)
von df
gs; (Ow. Aw. y)
Nominator and denominator of this equations are polynomials
of third degree:
3 b dul
2 du Ah
3.13
i=0 j=0 k=0
Normalization of pixel and geodetic coordinates is done
according next equations. Normalized values of coordinates will
be not more than 1:
1-0,
In = —
S,
s-0,
SN = ; tem———————
S e
9-0,
PN: =
Se
A03
An =
S;
h-0,
hy = ———
Sh
Output data will contain polynomial coefficients fio. Dto Cile
dii, and also normalizing parameters Oj, O,, Oy, Oy, Oy (Offset)
and S,S,, S, S, S, (Scale).
RPC calculation will be done according such algorithm:
e Calculate external orientation parameters for image
according rigorous sensor model and using control
points (or we can use external orientation parameters
calculated from navigation data);
e Calculate for all image and heights evenly distributed
control points (xg, yr, X, Y, Z) using rigorous sensor
model;
e Create equations and solve system with the help of
least mean square method, for RPC determination.
Tie points were searched in overlapped areas of CCD matrixes.
First video data lines placed in focal plane to overlap each third
frame of next matrix with first frame of previous matrix. Video
data frame consists of 985 lines. Every next frame in MSS has
overlap with previous frame in 57 lines. In PSS every next
frame has overlap with previous frame in 80 lines. Between
frames of different matrixes overlap is about 70 pixels.
We use combination of area matching algorithms and SURF for
tie points search.
Block adjustment is done with the account of CCD matrixes in
focal plane and using RPC. For block adjustment with tie points
we use additional information about surface heights from digital
elevation model or average height of earth surface.
One of output products is synthesized coverage with sizes from
23*10 to 23*20 km. This product can be used for increasing
productivity of image processing. Whole pixel coverage for
interesting area is done from adjusted block of images
excluding overlapped areas. RPC calculated for such
synthesized coverage.
While moving along orbit arises overlap of frames in different
spectral bands for MSS sensor “Canopus-V” satellite. We have
possibility to get digital elevation model by combined
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