ImageEnvelope - Image Envelope

Extracts an image envelope.

Detailed description

Build a vector data containing the polygon of the image envelope.

Parameters

This section describes in details the parameters available for this application. Table [1] presents a summary of these parameters and the parameters keys to be used in command-line and programming languages. Application key is ImageEnvelope .

[1]Table: Parameters table for Image Envelope.
Parameter Key Parameter Name Parameter Type
in Input Image Input image
out Output Vector Data Output vector data
sr Sampling Rate Int
elev Elevation management Group
elev.dem DEM directory Directory
elev.geoid Geoid File Input File name
elev.default Default elevation Float
proj Projection String
inxml Load otb application from xml file XML input parameters file
outxml Save otb application to xml file XML output parameters file

Input Image: Input image.

Output Vector Data: Vector data file containing the envelope.

Sampling Rate: Sampling rate for image edges (in pixel).

[Elevation management]: 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: 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: 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 (http://hg.orfeo-toolbox.org/OTB-Data/raw-file/404aa6e4b3e0/Input/DEM/egm96.grd).
  • Default elevation: 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.

Projection: Projection to be used to compute the envelope (default is WGS84).

Load otb application from xml file: Load otb application from xml file.

Save otb application to xml file: Save otb application to xml file.

Example

To run this example in command-line, use the following:

otbcli_ImageEnvelope -in QB_TOULOUSE_MUL_Extract_500_500.tif -out ImageEnvelope.shp

To run this example from Python, use the following code snippet:

#!/usr/bin/python

# Import the otb applications package
import otbApplication

# The following line creates an instance of the ImageEnvelope application
ImageEnvelope = otbApplication.Registry.CreateApplication("ImageEnvelope")

# The following lines set all the application parameters:
ImageEnvelope.SetParameterString("in", "QB_TOULOUSE_MUL_Extract_500_500.tif")

ImageEnvelope.SetParameterString("out", "ImageEnvelope.shp")

# The following line execute the application
ImageEnvelope.ExecuteAndWriteOutput()

Limitations

None

Authors

This application has been written by OTB-Team.