Description
A processing block that provides a SNAP polarimetric processing workflow that is applied on SAR scenes in the SAFE format.
See this block on the marketplace.
How it works
The SNAP block takes a Level 1C GRD image and generates a product ready for analysis by using a median filter for speckle filtering, creating a land-sea mask, and converting the image to the GeoTIFF format.
For each chosen polarization, a separate band will be generated in the output file. For instance, if both VV and VH polarizations are selected, the output will be a single GeoTIFF with two bands, one for VV and one for VH polarization.
| Parameter | Overview |
|---|---|
bbox | array of integers / required if Required if intersects or contains aren't specified.A bounding box to use as an AOI. Will clip to scenes that intersect with this box. |
contains | object / required if Required if bbox or intersects aren't specified.A GeoJSON geometry to use as an AOI. Will clip to scenes that fully cover this geometry. |
intersects | object / required if Required if bbox or contains aren't specified.A GeoJSON geometry to use as an AOI. Will clip to scenes that intersect with this geometry. |
polarisations | array of strings / required Requested polarization, vertical (V) or horizontal (H). The allowed values:
["VV"]. If the requested polarization is not available in the input image to SNAP, the operation will fail and give a corresponding error message. |
mask | string / required A type of surface to apply the mask to. The allowed values:
|
tcorrection | boolean / required Whether to apply Range Doppler Terrain Correction based on a suitable Digital Elevation Model (DEM). The default value is true. |
clip_to_aoi | boolean / required Whether the specified AOI should be clipped before processing:
false. |
calibration_band | array of strings / required Applies calibration to provide imagery in which the pixel values can be directly related to the radar backscatter of the scene. The allowed values:
sigma. |
speckle_filter | boolean / required Whether to apply Lee Sigma filter to remove speckle noise from the image. The default value is true. |
linear_to_db | boolean / required Whether to convert the pixel intensity to normalized radar cross-section measured in decibel units. The default value is true. |
Example
An example with Processing from Storage as a data source.
{
"up42-processing-from-storage:1": {
"asset_ids": ["00210895-5405-4c0r-9bca-ccca551776f9"]
},
"snap-polarimetric:1": {
"bbox": [13.358345031738283, 52.480689337378706, 13.395252227783203, 52.507654123207665],
"mask": null,
"contains": null,
"intersects": null,
"clip_to_aoi": true,
"tcorrection": true,
"linear_to_db": true,
"polarisations": ["VV"],
"speckle_filter": true,
"calibration_band": ["sigma"]
}
}Capabilities
Input
raster
| up42_standard | |
|---|---|
bands | {
"or": [
[
"HH",
"HV",
"alpha"
],
[
"VV",
"VH",
"alpha"
],
[
"HH",
"alpha"
],
[
"VV",
"alpha"
]
]
} |
dtype | uint16 |
format | SAFE |
sensor | Sentinel1GRD |
resolution | 10 |
processing_level | l1 |
Output
raster
| up42_standard | |
|---|---|
bands | > (propagated) |
dtype | {
"or": [
"uint16",
"float"
]
} |
format | GTiff |
sensor | > (propagated) |
resolution | > (propagated) |
processing_level | > (propagated) |
To know more please check the block capabilities specifications.