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Contour from ASTER GDEM Version 2

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#1
yeneneshabebe

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Hi all,

 

I was trying to generate a contour line for small and large area . First I decided to try with the small area. I mosaicked the different  DEMs and then project it to UTM after that, I tried to generate contours with different contour intervals and there are very noisy contours in all the intervals I used ( 10,20, 50 & 100). Just as an eg I have attached the 20m interval. What can I do to improve the noise? I tried by smoothing the DEM and not as such improved any advice or what I made wrong?

 

 

 

Thanks,

Yenenesh



#2
Daniel Huffman

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I'm not sure if I'll be able to help or not, but I just wanted to say that I don't see any attached image. I don't think it came through. Can you try again?



#3
yeneneshabebe

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Hi Daniel,

 

Thank you  very much for your help. I have to finish the work by this week so your help is very appreciated. This is from the non smoothed DEM, but as I said there is no much improvement also for the smoothed one. Attached here is the 20m contour.

 

Many thanks,

 

Yenenesh

 

 

Attached Files



#4
yeneneshabebe

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Hi all,

 

I am posting the topic again as I forgot to attach the file.

 

I was trying to generate contour from ASTER GDEM version 2. I have downloaded the images for  my area and I mosaicked them  and project to UTM. After that I tried to generate the contours with different contour intervals( 10, 20, 50 & 100) and there are very noisy contours in all the intervals I used. Just as an eg I have attached the 20m interval map. What can I do to improve the noise ?  I tried by smoothing the DEM and not as such improved any advice or what I made wrong?

 

 

 

Thanks very much,

 

Yenenesh 

 

Attached Files



#5
EOSGIS

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If the area of the DEM is a sand dunes area, or if it is in the sea (in ASTER) this is normal. For sand dunes because they are like this, for the sea because of the sensor. If it is a place with sea, then the only way is to mask or clean the water.
On other ASTER dem, in areas with snow, you can find noise or bugs...
What area is tjis about?
Best




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