(7)The panchromatic image of 1, 2.5 and eight meters and the 
multispectral images of 4, 10 and 16 meters were generated. 
Consequently, the Pa/Mu composite images of 1/4, 2.5/10 and 
8/16 meters were prepared. 
2.3 Interpretation 
The geographic information to be interpreted is determined from 
the legends of actual thematic maps shown in Table 2, because 
most of GIS data are generated from them. In case of a geological 
map, rock types were not interpreted because it was reported that 
geological classification was very difficult in the area with plants. 
Some unmapped items that are not specified in the legends but 
recognized clearly in the images like inter-change and shadows 
were also interpreted. 
The interpretation was carried out using the generated simulated 
images and actual satellite images of AVNIR. Both multi spectral 
image and Pan-sharpened image of AVNIR were interpreted. The 
band 2, 3 and 4 of AVNIR images were used for multi spectral 
bands, while the simulated images are in natural color. 
The interpretation was carried out under the following conditions. 
(1) The interpretability is dependent of the image scale. The inter 
pretation was performed on the display at any scale. 
(2) An expert with some experiences would interprets. 
(3) Absolute attributes(ex. university or college) were not 
necessary to interpret. 
(4) Only images would be interpreted . Existing maps would not 
be used as reference or preliminary knowledge. 
(5) The interpretability was ranked into 4 levels; l)derivable auto- 
matically(with computer), 2)well interpretable(by human 
interpretation), 3)poorly interpretable(to some extent), 
4)not interpretable. 
Table 2 Used maps 
Scale 
type of map 
1:10,000 
administration map 
1:25,000 
topographic map 
1:25,000 
land use map 
1:50,000 
geological map 
3. RESULTS 
The simulated images are clearer than real AVNIR images on the 
same scale. It seems that point spread function of simulated 
images is better than that of a real AVNIR image. The AVNIR 
image has band-to-band registration error to sonie extent. That is 
also the reason for image quality. 
Table 3 shows the summarized results of interpretation. Most of 
objects were easier to interpret in proportional to the spatial 
resolution. Forests and river regions are derivable from ADEOS 
images, because near infrared bands were available. 
4. CONCLUSION 
Inr order to evaluate what kinds of geographic information can be 
interpreted from high resolution satellite data, the following tasks 
were conducted.. 
(1) The high resolution satellite data were simulated from color 
air photographs. The atmospheric effects and data 
compression were applied to the generation of simulated 
images. 
(2) The geographic information extracted from satellite images 
was selected from the legends of existing maps with respect to 
map scales. 
It was proved through the study that the interpretable information 
would increase tremendously after the realization of spatial 
resolution of ALOS. The following studies should be carried out 
for more accuracy. 
(1) The development of algorithm for the generation of more 
accurate simulated images. 
(2) The check of pranimetric accuracy of the geographic inform 
ation derived from satellite data. 
(3) The analyses of the interpretation level and the suitable image 
enhancement for interpretation. 
REFERENCES 
[RESTEC, 1995] RESTEC, 1995, ‘Report on the Realization of 
ALOS Mission Requirements’ 
[Kawata, 1997] Y. Kawata, et al., 1997, ‘The estimation of 
Atmospheric Point Spread Function and Removal of 
Atmospheric Effects in the Frequency Domain’, Current 
Problems in the Atmosphere, Deepak Press 
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