IMG2GOOGLE(1) Generic Mapping Tools IMG2GOOGLE(1)NAMEimg2google - Create Google Earth KML overlay tiles from bathymetry Mer‐
cator img grid
SYNOPSISimg2google -Rwest/east/south/north[r] [ imgfile ] [ -Amode[altitude ] ]
[ -C ] [ -Ffademin/fademax ] [ -Gprefix ] [ -LLODmin/LODmax ] [ -Nlay‐
ername ] [ -Tdoctitle ] [ -UURL ] [ -V ] [ -Z ]
DESCRIPTIONimg2google reads a 1x1 minute Mercator surface relief img file and cre‐
ates a Google Earth overlay KML file and associated PNG tile for the
specified region. If no input file is given we use topo.11.1.img.
-R west, east, south, and north specify the Region of interest, and
you may specify them in decimal degrees or in
[+-]dd:mm[:ss.xxx][W|E|S|N] format. Append r if lower left and
upper right map coordinates are given instead of w/e/s/n. The
two shorthands -Rg and -Rd stand for global domain (0/360 and
-180/+180 in longitude respectively, with -90/+90 in latitude).
Alternatively, specify the name of an existing grid file and the
-R settings (and grid spacing, if applicable) are copied from
the grid.
OPTIONS
imgfile
An img format bathymetry/topography file such as those created
by Sandwell and Smith. If this files does not exist in the cur‐
rent directory and the user has set the environment variable
$GMT_DATADIR, then img2mercgrd will try to find imgfile in
$GMT_DATADIR.
-A Selects one of 5 altitude modes recognized by Google Earth that
determines the altitude (in m) of the image: G clamped to the
ground, g append altitude relative to ground, a append absolute
altitude, s append altitude relative to seafloor, and S clamp it
to the seafloor [Default].
-C Turn on clipping so that only portions below sea level will be
visible in the image [no clipping].
-F Sets the distance over which the geometry fades, from fully
opaque to fully transparent. These ramp values, expressed in
screen pixels, are applied at the minimum and maximum end of the
LOD (visibility) limits, respectively. [no fading (0/0)].
-G Specify the prefix for the output image file (the extensions are
set automatically). Default uses the naming
topoN|S<north>E|W<west>.
-L Measurement in screen pixels that represents the minimum limit
of the visibility range for a given Region Google Earth calcu‐
lates the size of the Region when projected onto screen space.
Then it computes the square root of the Region's area (if, for
example, the Region is square and the viewpoint is directly
above the Region, and the Region is not tilted, this measurement
is equal to the width of the projected Region). If this measure‐
ment falls within the limits defined by LODmin and LODmax (and
if the region is in view), the Region is active. If this limit
is not reached, the associated geometry is considered to be too
far from the user's viewpoint to be drawn. LODmax represents the
maximum limit of the visibility range for a given Region. A
value of −1, the default, indicates "active to infinite size."
[always active].
-N Append the layername of the image (use quotes if strings contain
spaces) [topoN|S<north>E|W<west>].
-T Append the document title (use quotes if strings contain spaces)
["Predicted bathymetry"].
-U By default, images are referenced locally relative to the KML
file. Specify an URL to prepend a server address to the image
name reference [local].
-V Selects verbose mode, which will send progress reports to stderr
[Default runs "silently"].
-Z Uses zip (which must be installed) to create a *.kmz file for
easy distribution; append + to delete the KML and PNG file after
zipping [No zipping].
EXAMPLES
To create a 10x10 degree Google Earth KML tile for the region -R
170/180/20/30 using the default topo.11.1.img and output naming conven‐
tion, try
img2google-R 170/180/20/30
To make the same tile with the previous topo.10.1.img, run in verbose
mode, clip so only oceanic areas are visible, name the output oldimage,
specify the KML metadata directly (including setting the image altitude
to 10 km), and make a single *.kmz file, try
img2google topo.10.1.img -R 170/180/20/30 -AA10000 -C -Goldimage -N"My
KML title" -T"My KML title" -U http://my.server.com/images -V -Z
DATA SETS
For topo.11.1.img and other Sandwell/Smith altimetry-derived Mercator
grids, visit http://topex.ucsd.edu.
SEE ALSOGMT(1), img2grd(1)img2mercgrd(1)ps2raster(1)GMT 4.5.14 1 Nov 2015 IMG2GOOGLE(1)
