Product Subset |

### Product Subset Definition

The dialog is divided into four tabs, each providing specific subset options.

#### Spatial Subset

If you are not interested in the whole image, you may specify an area of the product to be loaded. You can select the area by dragging the blue surrounding rectangle in the preview (see figure above). You can also specify the area manually either by pixel coordinates, by geo coordinates or by a polygon. If you drag the rectangle, the field values change simultaneously.

You can also specify a sub-sampling, by setting the values of `Scene step X` and `Scene step Y`.

When the input is a multisize product a combo for selecting the reference band is available. The pixel coordinates used are the pixel coordinates in this reference band.

NOTE: Pins outside of the spatial subset area will not be preserved in the resulting product, because they are bound to the pixel coordinates of the product.
GCPs are preserved, because they are bound to a geo-location.

A polygon can be defined in 2 ways:

- by loading it from a supported vector file, which can be in the following formats:
  - SHAPEFILE (*.shp)
  - KML (*.kml)
  - KMZ (*.kmz)
  - GEOJSON (*.json)
  - WKT (*.wkt)
  - TXT (*.txt)
  - PLACEMARK (*.placemark)
  - PNX (*.pnx)
- by defining it from a WKT string with pixel or geo coordinates

NOTE: The defined polygon must have 3 valid points (intersects the product bounds) to be used.

NOTE: The multi-polygons are not supported.

#### Band Subset

This tab is used to select the bands you want to have in your product subset.

This tab allows you to select individual bands from a list of available bands. To facilitate editing, quick-select check-boxes are available.

- "Select all" - checking this will select all available bands for the subset
- "Select none" - checking this will select no bands for the subset
- "Select band group" - checking this will select all bands that belong to the band group selected for the subset

#### Tie-Point Grid Subset

As with bands, this tab is used to select the tie-point grids you want to have in your product subset. The tie-point grids named `latitude` and `longitude` can not be deselected because they provide essential geo-coding information.

#### Metadata Subset

The tab lets you select/deselect meta-data records and tables. By default all meta-data tables are deselected, because they can be very huge for ENVISAT products and may reduce the performance of the Sentinel Toolbox.