Sample Extraction¶
Extracts samples values from an image.
Detailed description¶
The application extracts samples values from animage using positions contained in a vector data file.
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 SampleExtraction .
[1] | Table: Parameters table for Sample Extraction. |
Parameter Key | Parameter Type | Parameter Description |
---|---|---|
in | Input image | Input image |
vec | Input File name | Input File name |
out | Output File name | Output File name |
outfield | Choices | Choices |
outfield prefix | Choice | Use a prefix and an incremental counter |
outfield list | Choice | Use the given name list |
outfield.prefix.name | String | String |
outfield.list.names | String list | String list |
field | String | String |
layer | Int | Int |
ram | Int | Int |
inxml | XML input parameters file | XML input parameters file |
outxml | XML output parameters file | XML output parameters file |
InputImage: Support image.
Input sampling positions: Vector data file containing samplingpositions. (OGR format).
Output samples: Output vector data file storing samplevalues (OGR format). If not given, the input vector data file is updated.
Output field names: Choice between naming method for output fields. Available choices are:
- Use a prefix and an incremental counter: Use a prefix and an incremental counter.
- Output field prefix: Prefix used to form the field names thatwill contain the extracted values.
- Use the given name list: Use the given name list.
- Output field names: Full list of output field names.
Field Name: Name of the field carrying the classname in the input vectors. This field is copied to output.
Layer Index: Layer index to read in the input vector file.
Available RAM (Mb): Available memory for processing (in MB).
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_SampleExtraction -in support_image.tif -vec sample_positions.sqlite -outfield prefix -outfield.prefix.name band_ -field label -out sample_values.sqlite
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 SampleExtraction application
SampleExtraction = otbApplication.Registry.CreateApplication("SampleExtraction")
# The following lines set all the application parameters:
SampleExtraction.SetParameterString("in", "support_image.tif")
SampleExtraction.SetParameterString("vec", "sample_positions.sqlite")
SampleExtraction.SetParameterString("outfield","prefix")
SampleExtraction.SetParameterString("outfield.prefix.name", "band_")
SampleExtraction.SetParameterString("field", "label")
SampleExtraction.SetParameterString("out", "sample_values.sqlite")
# The following line execute the application
SampleExtraction.ExecuteAndWriteOutput()
Limitations¶
None
Authors¶
This application has been written by OTB-Team.