xarray-sentinel
WARNING: this product is a "technology preview" / pre-Alpha
Xarray backend to explore and load Copernicus Sentinel-1 satellite data products.
This Open Source project is sponsored by B-Open - https://www.bopen.eu
Features
- access to SLC burst data - technology preview
- access to metadata: product, orbit, attitude, GCPs - technology preview
- access to metadata: calibration, deramp - in roadmap
- products:
- Sentinel-1 SLC IW (Interferometric Wide Swath): technology preview
- Sentinel-1 SLC EW (Extended Wide Swath): technology preview
- Sentinel-1 SLC SM (Stripmap): in roadmap
- Sentinel-1 GRD SM/IW/EW: in roadmap
- Sentinel-2 L1C/L2A: in roadmap
Install
The easiest way to install xarray-sentinel is via conda.
Create a new environment, activate it, install the package and its dependencies,
as follows:
conda create -n xarray-sentinel
conda activate xarray-sentinel
conda install -c conda-forge rioxarray xmlschema
pip install xarray-sentinel
Sentinel-1 SLC IW
Data
Currently, xarray-sentinel provides access as Xarray datasets to the following data:
- burst data
- gcp
- orbit
- attitude
using azimuth_time and slant_range_time dimensions.
Examples:
Open root dataset
>>> from xarray_sentinel import sentinel1
>>> product_path = "tests/data/S1B_IW_SLC__1SDV_20210401T052622_20210401T052650_026269_032297_EFA4.SAFE"
>>> sentinel1.open_dataset(product_path)
<xarray.Dataset>
Dimensions: ()
Data variables:
*empty*
Attributes: (12/15)
constellation: sentinel-1
platform: sentinel-1b
instrument: ['c-sar']
sat:orbit_state: descending
sat:absolute_orbit: 26269
sat:relative_orbit: 168
... ...
sar:polarizations: ['VV', 'VH']
sar:product_type: SLC
xs:instrument_mode_swaths: ['IW1', 'IW2', 'IW3']
groups: ['IW1', 'IW1/calibration', 'IW1/gcp', 'IW1/at...
Conventions: CF-1.7
history: created by xarray_sentinel-...
The attribute groups shows the available groups to be loaded. The key group
shall be used to select the dataset to be loaded.
Open gcp dataset
To load the gcp relative to the first swath use the key group="IW1/gcp":
>>> sentinel1.open_dataset(product_path, group="IW1/gcp")
<xarray.Dataset>
Dimensions: (azimuth_time: 10, slant_range_time: 21)
Coordinates:
* azimuth_time (azimuth_time) datetime64[ns] 2021-04-01T05:26:24.20973...
* slant_range_time (slant_range_time) float64 0.005343 0.00536 ... 0.005679
line (azimuth_time) int64 0 1501 3002 ... 10507 12008 13508
pixel (slant_range_time) int64 0 1082 2164 ... 19476 20558 21631
Data variables:
latitude (azimuth_time, slant_range_time) float64 ...
longitude (azimuth_time, slant_range_time) float64 ...
height (azimuth_time, slant_range_time) float64 ...
incidenceAngle (azimuth_time, slant_range_time) float64 ...
elevationAngle (azimuth_time, slant_range_time) float64 ...
Attributes:
Conventions: CF-1.7
title: Geolocation grid
comment: The dataset contains geolocation grid point entries for eac...
history: created by xarray_sentinel-...
Open attitude dataset
>>> sentinel1.open_dataset(product_path, group="IW1/attitude")
<xarray.Dataset>
Dimensions: (azimuth_time: 25)
Coordinates:
* azimuth_time (azimuth_time) datetime64[ns] 2021-04-01T05:26:24.750001 .....
Data variables:
q0 (azimuth_time) float64 ...
q1 (azimuth_time) float64 ...
q2 (azimuth_time) float64 ...
q3 (azimuth_time) float64 ...
wx (azimuth_time) float64 ...
wy (azimuth_time) float64 ...
wz (azimuth_time) float64 ...
pitch (azimuth_time) float64 ...
roll (azimuth_time) float64 ...
yaw (azimuth_time) float64 ...
Attributes:
Conventions: CF-1.7
title: Attitude information used by the IPF during processing
comment: The dataset contains a sets of attitude data records that a...
history: created by xarray_sentinel-...
Open orbit dataset
>>> sentinel1.open_dataset(product_path, group="IW1/orbit")
<xarray.Dataset>
Dimensions: (axis: 3, azimuth_time: 17)
Coordinates:
* azimuth_time (azimuth_time) datetime64[ns] 2021-04-01T05:25:19 ... 2021-...
* axis (axis) <U1 'x' 'y' 'z'
Data variables:
position (axis, azimuth_time) ...
velocity (axis, azimuth_time) ...
Attributes:
reference_system: Earth Fixed
Conventions: CF-1.7
title: Orbit information used by the IPF during processing
comment: The dataset contains a sets of orbit state vectors tha...
history: created by xarray_sentinel-...
Open a single burst
>>> sentinel1.open_dataset(product_path, group="IW1/R168-N459-E0115")
<xarray.Dataset>
Dimensions: (azimuth_time: 1501, slant_range_time: 21632)
Coordinates:
pixel (slant_range_time) int64 0 1 2 3 ... 21629 21630 21631
line (azimuth_time) int64 10507 10508 10509 ... 12006 12007
* azimuth_time (azimuth_time) datetime64[ns] 2021-04-01T05:26:43.51577...
* slant_range_time (slant_range_time) float64 0.005343 0.005343 ... 0.005679
Data variables:
VH (azimuth_time, slant_range_time) complex128 ...
VV (azimuth_time, slant_range_time) complex128 ...
Attributes: (12/14)
constellation: sentinel-1
platform: sentinel-1b
instrument: ['c-sar']
sat:orbit_state: descending
sat:absolute_orbit: 26269
sat:relative_orbit: 168
... ...
sar:instrument_mode: IW
sar:polarizations: ['VV', 'VH']
sar:product_type: SLC
xs:instrument_mode_swaths: ['IW1', 'IW2', 'IW3']
Conventions: CF-1.7
history: created by xarray_sentinel-...
With the upcoming release of Xarray v0.18.0, xarray-sentinel will be automatically available as
an Xarray backend:
>>> import xarray as xr
>>> ds = xr.open_dataset(product_path, engine="sentinel-1")
