Compute Polyline Feature From Image
Brief Description
This application computes the chosen descriptors for each studied polyline contained in the input VectorData.
Tags
Feature Extraction
Long Description
The first step in the classifier fusion based validation is to compute the chosen descriptors for each studied polyline.
Parameters
Input Image (in): An image to compute the descriptors on.
Vector Data (vd): Vector data containing the polylines where the features will be computed.
Elevation management (elev): This group of parameters allows managing elevation values. Supported formats are SRTM, DTED or any geotiff. DownloadSRTMTiles application could be a useful tool to list/download tiles related to a product.
DEM directory (elev.dem): This parameter allows selecting a directory containing Digital Elevation Model files. Note that this directory should contain only DEM files. Unexpected behaviour might occurs if other images are found in this directory.
Geoid File (elev.geoid): Use a geoid grid to get the height above the ellipsoid in case there is no DEM available, no coverage for some points or pixels with no_data in the DEM tiles. A version of the geoid can be found on the OTB website(https://gitlab.orfeo-toolbox.org/orfeotoolbox/otb-data/blob/master/Input/DEM/egm96.grd).
Default elevation (elev.default): This parameter allows setting the default height above ellipsoid when there is no DEM available, no coverage for some points or pixels with no_data in the DEM tiles, and no geoid file has been set. This is also used by some application as an average elevation value.
Feature expression (expr): The feature formula (b1 < 0.3) where b1 is the standard name of input image first band
Feature name (field): The field name corresponding to the feature codename (NONDVI, ROADSA...)
Output Vector Data (out): The output vector data containing polylines with a new field
Load otb application from xml file (inxml): Load otb application from xml file
Save otb application to xml file (outxml): Save otb application to xml file
Limitations
Since it does not rely on streaming process, take care of the size of input image before launching application.
Authors
OTB-Team
See also
Example of use
in: NDVI.TIF
vd: roads_ground_truth.shp
expr: "(b1 > 0.4)"
field: NONDVI
out: PolylineFeatureFromImage_LI_NONDVI_gt.shp
otbcli_ComputePolylineFeatureFromImage -in NDVI.TIF -vd roads_ground_truth.shp -expr "(b1 > 0.4)" -field NONDVI -out PolylineFeatureFromImage_LI_NONDVI_gt.shp