Re: dfsg-free global digital elevation model (GDEM)?

[karme@berlios.de]

Hamish <hamish_b@yahoo.com> writes:

> karme writes:
>> I am looking for a DFSG-free [0] global digital elevation
>> model (GDEM) which I ultimately want to package for debian.
>>
>> is the SRTM [1] data DFSG-free?
>> 
>> think so:
>> http://www2.jpl.nasa.gov/srtm/mou.html
>
> yes it is, but probably not appropriate for inclusion in debian
> due to the large size of the dataset.

ok

>> rest of the world could be filled using GLOBE G.O.O.D. data
>
> if you are interested in such a thing I'd suggest one of the
> ETOPO series. (1,2,5 arc-min resolution)
> see  http://www.ngdc.noaa.gov/mgg/global/global.html
>
> In particular, etopo5 is old, but relatively small.

i am not sure etopo1 is better than GLOBE G.O.O.D. especially regarding
license issues (this starts driving me crazy)

for testing purpuses i created a GLOBE G.O.O.D. GDEM in geotiff format
(tiled internally and compressed) that is ~200MiB without overviews and
~300MiB including overviews.

(raw data would be:
43200 * 21600 * 2 MiB / (1024 * 1024) = 1779.78515625 MiB)

See also attached Makefile (I hope the attachment goes through)

> Better is to include tools to download what data you need on-
> the-fly I think, 

ok

> and the more immediate need is to package the Natural Earth dataset
> shapefiles.

ok

> see also http://grass.osgeo.org/wiki/Global_datasets

thanks

greetings
karme

# using bashisms
SHELL=/bin/bash

SRC="http://www.ngdc.noaa.gov/mgg/topo/DATATILES/elev/all10g.tgz";
METASRC="http://www.ngdc.noaa.gov/mgg/topo/elev/esri/hdr/";
MD5="f5b1bd95ac5c35aa974dce91c324072a"
INSTALL = install
INSTALL_DATA = $(INSTALL) -m 644
PACKAGE=dem-globe

all: dem-globe.tif

dem-globe.tif: dem-globe.vrt
	gdal_translate -a_srs epsg:4326 -of GTiff -co "TILED=YES" -co "COMPRESS=DEFLATE" -co "ZLEVEL=7" -co "PREDICTOR=2" $< $@
	gdaladdo -r cubic $@ 2 4 8 16 32 64 128

dem-globe.vrt: download-meta.stamp
	mv -v all10/a11g all10/a10g
	gdalbuildvrt $@ $$(echo all10/{a..p}10g)

download.stamp:
	[ "$$(md5sum all10g.tgz |cut -f 1 -d " ")" = "$(MD5)" ] || { wget -nc "$(SRC)" && [ "$$(md5sum all10g.tgz |cut -f 1 -d " ")" = "$(MD5)" ] ; } && touch $@ || rm -vf all10g.tgz

unpack.stamp: download.stamp
	tar xzf all10g.tgz && touch $@

download-meta.stamp: unpack.stamp
	cd all10 && for i in {a..p}; do wget -nc $(METASRC)/$${i}10g.hdr; done && cd .. && touch $@

clean:
	rm -vf *.stamp *~ dem-globe.tif dem-globe.vrt all10g.tgz
	rm -rvf all10

installdirs:
	$(INSTALL) -d $(DESTDIR)/usr/share/dem-data
	$(INSTALL) -d $(DESTDIR)/usr/share/doc/$(PACKAGE)

install: installdirs
	$(INSTALL_DATA) dem-globe.tif $(DESTDIR)/usr/share/dem-data
	$(INSTALL_DATA) README $(DESTDIR)/usr/share/doc/$(PACKAGE)
	$(INSTALL_DATA) COPYING $(DESTDIR)/usr/share/doc/$(PACKAGE)
	$(INSTALL_DATA) globedocumentationmanual.pdf $(DESTDIR)/usr/share/doc/$(PACKAGE)

Prerequisites / build dependencies:
- gnu make
- md5sum
- bash
- wget
- gdal
- internet connection

Run:
make
and
make install