I try to generate world coastline 1:30000 from ASTER's DEM with:
gdal_contour -a ELEVATION -fl 0
But above produce some of missing coastlines. Whats happening? Is it cliffy shore? How would you generate coastline?
Note: If I use 0.5 it will show all but I'm afraid it'd be inaccurate. Furthermore how to cleanup "tails" using v.clean?
I found ASTER mirror (mediafire) here: http://sasgis.ru/forum/viewtopic.php?f=21&t=1848&start=360