geotiff-extents
compute the corner and center bounding coordinates for a geotiff
example
var fs =var geotiff =var epsg =var extents =var data = fsvar im = geotiffvar fd = imvar gk = imconsole
output:
$ node extents.js LC80700192015294LGN00_B2.TIF
{ upperLeft: [ -155.62757614534797, 59.781490186078884 ],
lowerLeft: [ -155.46612438446172, 57.56866631571051 ],
upperRight: [ -151.27624278582903, 59.79644709112181 ],
lowerRight: [ -151.3822362875974, 57.58238285553903 ],
center: [ -153.4380373185701, 58.69959098078464 ] }
and this output matches up with the listgeo command:
$ listgeo -d LC80700192015294LGN00_B2.TIF | tail -n5
Upper Left ( 352500.000, 6630000.000) (-155.6275761,59.7814902)
Lower Left ( 352500.000, 6383370.000) (-155.4661244,57.5686663)
Upper Right ( 596730.000, 6630000.000) (-151.2762428,59.7964471)
Lower Right ( 596730.000, 6383370.000) (-151.3822363,57.5823829)
Center ( 474615.000, 6506685.000) (-153.4380373,58.6995910)
api
var extents =
var ex = extents(opts)
Compute the bounding and center coordinates ex
given:
opts.tiePoint
- an array (or Float64Array etc) ofK*6
tie point coordinates mapping(I,J,K)
points in raster space to(X,Y,Z)
points in model space.opts.pixelScale
- an array (or Float64Array etc) of 3 sizes for raster spacing in model space unitsopts.width
- width of the image in raster (pixel) coordinatesopts.height
- height of the image in raster (pixel) coordinatesopts.proj
-proj4(src,dst)
coordinate transform implementationopts.from
- proj string describing the tie point coordinate systemopts.to
- proj string describing the output coordinate system
The georeferencing tags are defined in more detail in 2.6.1 GeoTIFF Tags for Coordinate Transformations.
The output object ex
has these properties, which map to 2-element coordinate
pair arrays in the coordinate system specified by opts.to
:
ex.upperLeft
ex.lowerLeft
ex.upperRight
ex.lowerRight
ex.center
install
npm install geotiff-extents
license
BSD