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Purpose

 

This panel enables to modify some specific processing parameters.  

 

Technical Note

 

Doppler Polynomial

The original doppler polynomial is converted into the SARscape standard. The doppler variations are mostly in range direction, but in some cases (e.g. spotlight or topsar acquisition modes) the doppler varies notably also in azimuth direction. For this reason the image is divided into stripes, whose number in azimuth direction is defined by the "Azimuth Poly Number" parameter; a new doppler polynomial is estimated for each strip. The doppler variation, from one to the next strip, is defined by the "Azimuth Doppler Dependency".

 

 

Parameters - General Parameters

 

Automatic Look Computation

The number of looks will be computed automatically.

 

Doppler Polynomial

In the formulas below R and A are the pixel position respectively in range and in azimuth direction.

 

Doppler RG Poly Degree        

Polynomial degree in range direction.

doppler = K1 + K2R+ K3R2 + K4R3

 

Doppler AZ Poly Degree        

Polynomial degree in azimuth direction.

doppler =  K1 + K2A+ K3A2 + K4A3

 

Doppler AZ Poly Number

Number of stripes in azimuth direction.

 

Multilooking

 

Azimuth looks        

Number of looks in azimuth direction.

 

Range looks        

Number of looks in range direction.

 

Block Size

In order to speed up the processing of large files, the data are divided in blocks whose dimension is specified here in pixels. Depending on the specific resolution of the system, this parameter should be set in order not to exceed 1.5 Gigabytes of memory allocation. The default setting is suitable for sensors such as ERS and ENVISAT ASAR. In order to check what is the maximum value to set, the following formula can be adopted:

 

Block Size = 1.5/2*4*Number of Columns

 

Block Overlap

The number of overlapping pixels between adjacent blocks is specified.

 

Scene Limit Increment

In order to avoid the possibility to cut out some image portions during processes where a rotation (such as the geocoding process) is involved, an additional area - to add on each of the four image sides - is specified in metres. Values different from zero must be entered.

 

Cartographic Grid Size

The default output grid spacing, which is used when the geocoding/transformation onto a cartographic reference system is carried out (e.g. geocoding, Digital Elevation Model generation, etc.); the default unit of measure is meters. The same grid size in Easting and Northing direction must be entered; however different Easting and Northing grid sizes can be specified in the specific processing panels.

Note that - for the Geographic projection - if values higher than 0.2 are entered they will be considered as metric units and then automatically, and roughly, converted from meters to degrees; if values lower than 0.2 are entered they will be considered as degree and used as such without any conversion.

 

Mean Window Size

The window for the mean filtering is specified.

 

Interpolation Window Size

The window for the interpolation of dummy (i.e. Not a Number) values is specified.

 

Orbit Interpolation

It represents the multiplying factor, which is used to calculate the orbit position by means of the point distribution in azimuth direction. The higher the value the longer the processing time.

 

Resampling Method

By setting the relevant flag, the interpolation method - which is used during processes where pixel geometric transformations occur (e.g. under/over sampling, file transformation, etc.) - is specified.

 

Nearest Neighbour        

 

Bilinear Interpolation

 

3rd Order Cubic Convolution

 

4th Order Cubic Convolution

 

Quick Look Format        

Select the format of the Quick Look (TIFF or PNG). The Generate Quick Look flag must be set to TRUE.

 

General Functions

 

Load Preferences

It allows loading specific Preferences tthirteen different settings  as possible alternative default processing values.

 

Load

It allows loading an .xml, .sml or .txt file where SARscape common Preferences where previously saved.

 

Save

It allows saving SARscape common Preferences for a future processing using the same preferences characteristics.

 

Help        

Specific help document section.

 

 

Ok        

The selected default processing parameters are loaded.

 

Cancel        

The window will be closed.

 

Specific Function(s)        

 

None.

 

References

 

None.