InWF : Filtered Wrapped Interferogram
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Product Description
-------------------

This product corresponds to the **filtered** wrapped interferogram. 

The geotiff file  has 2 bands:

+ **band 1** is the **filtered** wrapped phase (phase difference between the two acquisitions) of the interferogram, corrected from stratified atmospheric delay (if asked) and from spectral diversity. It is by default filtered by a moving average, triangular window, filter. Multilooking is that defined with Rlooks_unw and given in nsbas.proc file.
+ **band 2** is either the product of the two image's amplitudes (if ROIPAC Goldstein filter is used) or a coherence (if a Sliding window filter is used (SW)). The coherence is obtained when the sliding window average is applied on the wrapped interferogram phase: it thus quantifies the quality of the filtered phase (1: good quality, 0: no coherence).

The png file has 1 band:

+ **band 1** is the **filtered** wrapped phase of the interferogram, normalized by a color palette.


Available products
-------------------

The InWF produts are available in one resolution:

- runw= 8 (resolution of interferogram wrapped)

The InWF produts are computed in two geometries (in radar : InWF_radar_ and in ground geometry : InWF_geo_):  

.. _InWF_radar : InWF_radar.html
.. _InWF_geo : InWF_geo.html

.. toctree::
   :maxdepth: 4
   
   InWF_radar
   InWF_geo

Processing Details
-----------------------

The filtering of the wrapped interferogram is done in a sliding window, and it use the coherence as a weigthing.

In the **metadata** file, the following parameters are the filtering options:

- ``FilterStrength`` : Strengh of the filter for the Goldstein filter, if used 
- ``filterstyle`` : the selected filter (Goldstein, Sliding Window, or others)
- ``SWwindowsize`` : width of triangular subwindows for the filtering, if Sliding Window 
- ``SWamplim`` : amplitude threshold