Karl's IPW experience
Contents
DEM in albers into IPW
The result is an image with four headers. The upper left corner is referred to as line 0, sample 0.
1) converted SierraBB-500m.tif to ASCII using ArcGIS Conversion Tools > From Raster > Raster to ASCII
2) stripped header with Wordpad
3) text2ipw -l 1450 -s 876 -b 1 -n 16 snbb500m.txt > dem.ipw
4) mkgeoh -c albers -u meters -o 389271.181648,-218640.76643 -d -500,500 dem.ipw > dem.geo.ipw
!<header> basic_image_i -1 $Revision: 1.11 $ byteorder = 0123 nlines = 1450 nsamps = 876 nbands = 1
!<header> basic_image 0 $Revision: 1.11 $ bytes = 2 bits = 16 history = text2ipw -l 1450 -s 876 -b 1 -n 16 snbb500m.txt
!<header> lq 0 $Revision: 1.6 $ map = 0 -10.99219036 map = 65535 4254.503906
!<header> geo 0 $Revision: 1.7 $ bline = 389271.181648 bsamp = -218640.76643 dline = -500 dsamp = 500 units = meters coord_sys_ID = albers
DEM in WGS84 into IPW
1) converted SierraBB-500m_wgs84 ASCII using ArcGIS Conversion Tools > From Raster > Raster to ASCII
2) stripped header with Textpad
3) replaced -9999 (no data) with 0 so that lq header would only go from dem min to max
3) text2ipw -l 1261 -s 1008 -b 1 -n 16 sierrabb-500m_wgs84.txt > demwgs84.ipw
4) mkgeoh -c 'geo' -u degrees -o -41.5206376,-122.615503 -d -0.0051981894,0.0051981894 demwgs84.ipw > demwgs84.geo.ipw
view factor for DEM spanning more than 1 degree
gviewf demwgs84.geo.ipw > demwgs84.gviewf.ipw
demux -b 0 demsfa2.gviewf.ipw > vf.ipw
demux -b 1 demsfa2.gviewf.ipw > ct.ipw
ipw2pbm vf.ipw > vf.pbm
ipw2pbm ct.ipw > ct.pbm
view factor for 90m SRTM DEM spanning more than 1 degree
mkgeoh -c geo -u degrees -o 41.520910931,-122.615503265 -d -0.00083333333,0.00083333333 snbb_90m_wgs84.ipw > snbb_90m_wgs84.geo.ipw