Output of "autoRIFT" module for a pair of Sentinel-1A/B images (20170221-20170227; same as the Demo dataset at https://github.com/leiyangleon/Geogrid) at Jakobshavn Glacier of Greenland over user-defined map-projected Cartesian (northing/easting) coordinate grid (same grid used in the Demo at https://github.com/leiyangleon/Geogrid): (a) estimated range pixel displacement (in pixels), (b) estimated azimuth pixel displacement (in pixels), (c) light interpolation mask, (d) chip size used (in pixels). Notes: all maps are established exactly over the same map-projected Cartesian coordinate grid from input.
This is done by implementing the following command line:
With ISCE:
testautoRIFT_ISCE.py -m I1 -s I2 -g winlocname -o winoffname -sr winsrname -csmin wincsminname -csmax wincsmaxname -vx winro2vxname -vy winro2vyname
where "I1" and "I2" are the reference and secondary images as defined in the section of instructions below, and the optional inputs "winlocname", "winoffname", "winsrname", "wincsminname", "wincsmaxname", "winro2vxname", "winro2vyname" are outputs from running "testGeogrid.py" as defined at https://github.com/leiyangleon/Geogrid. For full/combinative use of these optional inputs, please refer to the section of instructions below. For the simplified use when the geocoded product is desired, "winlocname" (grid location) must be specified (otherwise it will become the demo in Section 5.3), and each of the rest optional input ("win * name") can be either used or omitted.
Runtime comparison for this test (on an OS X system with 2.9GHz Intel Core i7 processor and 16GB RAM):
- autoRIFT (single core): 10 mins
- Dense ampcor from ISCE (8 cores): 90 mins
Final motion velocity results by combining outputs from "Geogrid" (i.e. matrix of conversion coefficients from the Demo at https://github.com/leiyangleon/Geogrid) and "autoRIFT" modules (i.e. estimated range/azimuth pixel displacement shown above): (a) estimated motion velocity from Sentinel-1 data (x-direction; in m/yr), (b) reference motion velocity from input data (x-direction; in m/yr), (c) estimated motion velocity from Sentinel-1 data (y-direction; in m/yr), (d) reference motion velocity from input data (y-direction; in m/yr). Notes: all maps are established exactly over the same map-projected Cartesian (northing/easting) coordinate grid from input.