Extract ROI¶
Extract a ROI defined by the user.
Detailed description¶
This application extracts a Region Of Interest with user defined size, or reference image.
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 ExtractROI .
[1] | Table: Parameters table for Extract ROI. |
Parameter Key | Parameter Type | Parameter Description |
---|---|---|
in | Input image | Input image |
out | Output image | Output image |
ram | Int | Int |
mode | Choices | Choices |
mode standard | Choice | Standard |
mode fit | Choice | Fit |
mode.fit.ref | Input image | Input image |
mode.fit.elev | Group | Group |
mode.fit.elev.dem | Directory | Directory |
mode.fit.elev.geoid | Input File name | Input File name |
mode.fit.elev.default | Float | Float |
startx | Int | Int |
starty | Int | Int |
sizex | Int | Int |
sizey | Int | Int |
cl | List | List |
inxml | XML input parameters file | XML input parameters file |
outxml | XML output parameters file | XML output parameters file |
Input Image: Input image.
Output Image: Output image.
Available RAM (Mb): Available memory for processing (in MB).
Extraction mode Available choices are:
- Standard: In standard mode, extract is done according the coordinates entered by the user.
- Fit: In fit mode, extract is made to best fit a reference image.
- Reference image: Reference image to define the ROI.
- 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.
Start X: ROI start x position.
Start Y: ROI start y position.
Size X: size along x in pixels.
Size Y: size along y in pixels.
Output Image channels: Channels to write in the output image.
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_ExtractROI -in VegetationIndex.hd -startx 40 -starty 250 -sizex 150 -sizey 150 -out ExtractROI.tif
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 ExtractROI application
ExtractROI = otbApplication.Registry.CreateApplication("ExtractROI")
# The following lines set all the application parameters:
ExtractROI.SetParameterString("in", "VegetationIndex.hd")
ExtractROI.SetParameterInt("startx", 40)
ExtractROI.SetParameterInt("starty", 250)
ExtractROI.SetParameterInt("sizex", 150)
ExtractROI.SetParameterInt("sizey", 150)
ExtractROI.SetParameterString("out", "ExtractROI.tif")
# The following line execute the application
ExtractROI.ExecuteAndWriteOutput()
Limitations¶
None
Authors¶
This application has been written by OTB-Team.