International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B4. Istanbul 2004 
  
It is very important to bear in mind that the correlation softly coloured SPOT images, in which the colour tones have man 
coefficient between the Landsat TM visible and SPOT been obtained from the Landsat TM ones. 
panchromatic bands is quite high (around 0.83), but this 
value decreases considerably (to about 0.72) for the Landsat The geostatistically merged image is more similar to the "Mear 
infrared bands. Landsat TM original images, but the visual quality of the Std.E 
image is better. For example, to highlight the improvement Min 
obtained with the integration, several linear features (roads) Max 
4. RESULTS that are difficult to distinguish are labelled (labels 1 to 4) in — 
Figure 4. — 
To demonstrate the potential of the proposed methodology, 
the results of the application to the Landsat TM (bands 5,4 Another very interesting analysis is the statistical 
and 3) and SPOT-PAN images are presented. characteristics comparison (Table 3). In this table we can see M 
a better conservation of statistical characteristics using the Sd: 
In Figure 4, the resultant images obtained from the classical geostatistical merging procedure. In the simulation process, M 
methods are shown. Figure 4D shows the HSV merged image several conditions are applied in order to preserve these e 
and 4E the CN merged image. In Figure 4C, the final merged characteristics. The merged bands must have a mean similar 
image obtained from the geostatistical proposed method to that of the original Landsat TM bands and their variance 
using the geostatistical direct cosimulation technique is and variogram characteristics must be influenced by the 
presented. variability characteristics of the SPOT-P image (it is TM 
important to bear in mind that the SPOT-P image is the only TM: 
First of all, we can evaluate the visual appearance of the reference of the variability in terrain characteristics for a 10m TM 
merged images. The obtained images are markedly different. pixel size). Also, it is very important to emphasize that thi TM. 
Thus the images obtained from the classical methods show a conservation is not verified for the traditional methods due to TM. 
close resemblance with the SPOT-P one making the photo the necessary transformation that is applied previously to the TM 
interpretation easier. These images have a final aspect of merging process. PAD 
CN! 
CN: 
CN: 
CN: 
CN: 
CN’ 
PAN 
  
Figure 4. A: SPOT-P image; B: Landsat-TM image; C: GEOSTAT TM-PAN merged image; D: HSV TM-PAN merged image; E 
CN TM-PAN image. RGB bands: 5,4,3. Linear expansion 2% (more information in the text). 
  
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