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Purpose

 

Statistical parameters, for one or more data files, are extracted.

 

The calculated values are automatically visualized at process completion. When two or more input files are entered, the program generates two views showing the temporal signature in dB and linear backscatter values.

 

Technical Note

The following parameters are calculated:

 

•Number of data points.

•Minimum pixel value.

•Maximum pixel value.

•Mode value.

•Standard deviation value.

•Normalisation Factor.

•Median value.

•Mean value.

•Radiometric Resolution (in dB). It is calculated for power images using the following formula: 10 * log10(  (1.0 + aQR) ); where aQR = Standard Deviation / Mean value

•Equivalent Number of Looks. It is calculated using the following formula: mean2 / standard deviation2

 

*The equivalent number of looks is computed if an homogenous area is selected. It is not meaningful for an entire scene.

 

•Equivalent Number of Looks entire (Partitioned Least-Sqares Fit estimation method). It is based on methods described in  Lee, J. S., and K. Hoppel (1999) and Ramponi et al. 1999.

 

The calculation can be performed on the entire scene or on a selected area of interest. The "Input file list" is automatically sorted in chronological order before generating the temporal signature.

 

Input Files

 

Input file list

Input file name(s) of the data to analyse. This file list is mandatory.

 

Optional Files

 

Vector File        

A vector file (.shp) can be entered to specify the area to be processed. This file is optional.

 

Parameters - Principal Parameters

 

If a vector file defining the Area of Interest is not specified, cartographic co-ordinates (geocoded data) or file co-ordinates (not geocoded data) can be entered as follows:

 

West/First column

The Westernmost cartographic co-ordinate or the first column file co-ordinate.

 

East/Last column

The Easternmost cartographic co-ordinate or the last column file co-ordinate.

 

North/First row

The Northernmost cartographic co-ordinate or the first row file co-ordinate.

 

South/Last row

The Southernmost cartographic co-ordinate or the last row file co-ordinate.

 

Parameters - Global

 

It brings to the general section of the Preferences parameters. Any modified value will be used and stored for further processing sessions.

 

Parameters - Other Parameters

 

It brings to the general section of the Preferences parameters. Any modified value will be used and stored for further processing sessions.

 

Output Files

 

Output File

Enter the name of the output file. This file list is mandatory.

 

The calculated statistical parameters and related graphs are shown on screen.

 

_sta        

Text file containing the value calculated for each statistical parameter.

 

General Functions

 

Exec

The processing step is executed.

 

Store Batch        

The processing step is stored in the batch list. The Batch Browser button allows to load the batch processing list.

 

Close        

The window will be closed.

 

Help

Specific help document section.

 

 

Specific Function(s)

 

None.

 

See Also

 

Task, SARscapeBatch object, SARscapeBatch script example

 

References

 

Lee, J. S., and K. Hoppel. "Noise modeling and estimation of remotely-sensed images." 12th Canadian Symposium on Remote Sensing Geoscience and Remote Sensing Symposium,. Vol. 2. IEEE, 1989.

 

Ramponi, G., D'Alvise, R., & Moloney, C. (1999, June). Automatic estimation of the noise variance in SAR images for use in speckle filtering. In NSIP (pp. 835-838).