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International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part BI. Istanbul 2004 
deconvolution filter has to be applied in order to avoid 
artifacts due to divergence near fe/2 frequency. 
Restoration. of image contrast is performed by linear 
filtering, to which a noise correction process is added to 
limit initial image noise from being amplified by 
deconvolution. This de-noising process relies upon a 
wavelet transform operation of the image, on which 
threshold techniques are applied. 
The resulting panchromatic Modulation Transfer Function 
(MTF) at system level is 0.2 at Nyquist frequency (while the 
value was 0.09 at instrument level), and much higher for 
lower frequencies, with a signal to noise ratio kept to 90 (at 
nominal Earth radiance) by this restoration process. 
It shows that The Pléiades Panchromatic image has an 
information content of higher quality than a non-restored 
image that would have been acquired by a much larger and 
therefore far more costly instrument. 
4.7 Deliverable products 
Pléiades HR. should deliver ready-to-use products which 
could be easily integrated in GIS and/or transformed into 
thematic information while combined with other satellite, 
airborne or ground information. Standard products are not 
any more raw data but accurately corrected images, using 
internal calibration parameters, ephemeris and attitude 
measurements. 
  
Fig. 9 True color image 
A "perfect sensor" image can be generated, removing all 
distortions excepted parallaxes due to the terrain altitude. 
Basic images will contain both panchromatic channel (at 0.7 
m resolution at nadir) and multispectral ones (4 bands with 
2.8 m resolution at nadir) already registered and merged. 
Among these standard products three examples can be 
given: 
-  Orthorectified products will be generated using a 
Digital Elevation Model (DTM). Each product will 
contain 5 spectral bands (panchromatic, B0,B1,B2 and 
B3) re-sampled on a same 0.7 m cartographic grid. 
- Simultaneous stereo pairs or triplets will be provided, 
with different coverage sizes (up to 300km x 20km or 
150km x 40km). From these stereo data DEM could be 
derived with a very high altimetric accuracy (about 2 
m) 
- . Mosaics (up to 120km x 120km) using images acquired 
from the same orbit, thanks to the agility of the system. 
With the panchromatic and multispectral bands images 
could be visualized either in black and white (Fig.8), in true 
color (Fig. 9) or in false color (Fig. 10) 
Ji ; 
Fig. 10 False color image 
  
4.8 Acquisitions capabilities 
4.8.1 Imaging modes: Each satellite should be able to 
deliver more than 250 images per day (a 450 image capacity 
could be achieved sometimes). In all modes, the system 
should be able to deliver as well false color images, and true 
color ones, using the four channels blue, green, red, and 
near-infrared. 
Due to its high agility and high performance of the guidance 
algorithms, the satellite is capable to image targets along any 
ground direction within 47° of vertical viewing position, with 
very low maneuvers durations between two consecutive 
images.