Jump to content

 
Photo

gtopo 30 - simplify

- - - - -

  • Please log in to reply
5 replies to this topic

#1
gregory

gregory

    Key Contributor

  • Validated Member
  • PipPipPip
  • 96 posts
  • Gender:Male
  • Location:Cracow
  • Poland

hello;
It's nice to write my first post here. I'm a member for some time, but now is a time to ask :)
I want to simplify gtopo 30 DEM for Asia,I tried to use Focal Statistics in ArcGIS . The answer it gives me back, doesn't satisfied me beacouse of the shape of the seashare. Small isles loose them shape and looks like dots , and the seashare it too much generalized. The look of the interior it's ok for me. I tried to use various level of neighborhood settings but it doesnt change to much. Any suggestions are welcome,
Glad to post
grettings from poland
gregory

#2
Rob

Rob

    Legendary Contributor

  • Moderator
  • PipPipPipPipPip
  • 418 posts
  • Gender:Male
  • Location:Kailua, Hawaii
  • Interests:anything outside.
  • United States

i use leveller for most of my dem manipulation tasks, including smoothing/generalizations. nice little program w/ great support.

http://www.daylongra...ducts/leveller/

#3
gregory

gregory

    Key Contributor

  • Validated Member
  • PipPipPip
  • 96 posts
  • Gender:Male
  • Location:Cracow
  • Poland

thanks for the quick answer, i ll have a look at that solution,
the way i think to solve that problem i described before, is to prepare a condition (maybe in raster calculator) in which the cells bordering with the seaside shouldn't be used....

#4
Andrew

Andrew

    Master Contributor

  • Validated Member
  • PipPipPipPip
  • 102 posts
  • Gender:Male
  • Location:Australia
  • Interests:Web development, and golf!
  • Australia

Hi,

If you want to use the path you described above, you could create a mask which defines the areas you need and set that in the raster calculator options. Another handy tool is the neighbourhood statistics in Spatial Analyst toolbar drop down list, you can choose the statistic type you want to use and the extent of the neighbourhood. Maybe someone else out there might be able to shed more light on that second option for you, as I haven't used it but I can see potential there.

Andrew

#5
Martin Gamache

Martin Gamache

    Ultimate Contributor

  • Associate Admin
  • PipPipPipPipPipPip
  • 980 posts
  • Gender:Male
  • Location:Washington DC
  • Interests:History of Topographic Cartography
    Topographic Mapping
    History of Relief Depiction
    Thematic Cartography
    Demographic Cartography
    Cartographic techniques, methods, and tools
    Orienteering
    Panoramic & Kite Photography
  • United States

You could use a mode or median filter and writing that into the calculator should be fairly easy to do. I'm sure someone has posted how to do that somewhere inthe ESRI knowledge base.

#6
gregory

gregory

    Key Contributor

  • Validated Member
  • PipPipPip
  • 96 posts
  • Gender:Male
  • Location:Cracow
  • Poland

Thanks for all advices,
It's remind me the way I used to do but with Photoshop (also median filter). It's maybe not to the end professional (i dont know exaclly the way it works) but the effect of generalisation comapared to maps that Im sure about, it's ok.It also works much more faster than ArcGIS with a preview during operation.
Sorry for my english
Thanks one more time
gregory




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users

-->