import bokeh.io
bokeh.io.output_notebook()
import holoviews as hv
hv.extension('bokeh')
import datashader as ds
from holoviews.operation.datashader import datashade,rasterize
from IPython.display import display, HTML

Loading BokehJS ...

import xsar
import xsarsea

Ouverture full resolution

filename = '/home/alevieux/Documents/Data/S1A_IW_GRDH_1SDV_20170907T103020_20170907T103045_018268_01EB76_992F.SAFE'
sar_ds = xsar.open_dataset(filename)[0]
sar_ds

<xarray.Dataset>
Dimensions:         (atrack: 16778, pol: 2, xtrack: 25187)
Coordinates:
  * pol             (pol) object 'VV' 'VH'
  * atrack          (atrack) int64 0 1 2 3 4 5 ... 16773 16774 16775 16776 16777
  * xtrack          (xtrack) int64 0 1 2 3 4 5 ... 25182 25183 25184 25185 25186
Data variables:
    digital_number  (pol, atrack, xtrack) uint16 dask.array<chunksize=(2, 4195, 4198), meta=np.ndarray>
    time            (atrack) datetime64[ns] dask.array<chunksize=(4195,), meta=np.ndarray>
    longitude       (atrack, xtrack) float32 dask.array<chunksize=(4195, 4198), meta=np.ndarray>
    latitude        (atrack, xtrack) float32 dask.array<chunksize=(4195, 4198), meta=np.ndarray>
    incidence       (atrack, xtrack) float32 dask.array<chunksize=(4195, 4198), meta=np.ndarray>
    elevation       (atrack, xtrack) float32 dask.array<chunksize=(4195, 4198), meta=np.ndarray>
    sigma0_raw      (pol, atrack, xtrack) float64 dask.array<chunksize=(2, 4195, 4198), meta=np.ndarray>
    nesz            (pol, atrack, xtrack) float32 dask.array<chunksize=(2, 4195, 4198), meta=np.ndarray>
    gamma0_raw      (pol, atrack, xtrack) float64 dask.array<chunksize=(2, 4195, 4198), meta=np.ndarray>
    negz            (pol, atrack, xtrack) float32 dask.array<chunksize=(2, 4195, 4198), meta=np.ndarray>
    sigma0          (pol, atrack, xtrack) float64 dask.array<chunksize=(2, 4195, 4198), meta=np.ndarray>
    gamma0          (pol, atrack, xtrack) float64 dask.array<chunksize=(2, 4195, 4198), meta=np.ndarray>
Attributes:
    footprint:       POLYGON ((-67.84221143971432 20.72564283093837, -70.2216...
    coverage:        251km * 170km (xtrack * atrack )
    pixel_xtrack_m:  10.0
    pixel_atrack_m:  10.2
    ipf_version:     2.84
    swath_type:      IW
    polarizations:   VV VH
    product_type:    GRD
    mission:         SENTINEL-1
    satellite:       A
    start_date:      2017-09-07 10:30:20.936409
    stop_date:       2017-09-07 10:30:45.935264
    path:            /home/alevieux/Documents/Data/S1A_IW_GRDH_1SDV_20170907T...
    denoised:        {'VH': False, 'VV': False}
    subdataset:      IW
    geometry:        {'VH': {'atrack':   atracks xtracks                     ...
    Conventions:     CF-1.7

rasterize(hv.Image(
            sar_ds.sigma0.sel(pol='VV')
            ).opts(clim=(0,0.4), cmap='gray',colorbar=True,tools=['hover'],title="xsar"))

Ouverture 200m resampling par defaut (average)

filename = '/home/alevieux/Documents/Data/S1A_IW_GRDH_1SDV_20170907T103020_20170907T103045_018268_01EB76_992F.SAFE'
sar_ds_200m = xsar.open_dataset(filename, resolution={'xtrack':20, 'atrack':20})[0]
sar_ds_200m

<xarray.Dataset>
Dimensions:         (atrack: 838, pol: 2, xtrack: 1259)
Coordinates:
  * pol             (pol) object 'VV' 'VH'
  * atrack          (atrack) int64 10 30 50 70 90 ... 16690 16710 16730 16750
  * xtrack          (xtrack) int64 10 30 50 70 90 ... 25110 25130 25150 25170
Data variables:
    digital_number  (pol, atrack, xtrack) uint16 dask.array<chunksize=(2, 838, 1259), meta=np.ndarray>
    time            (atrack) datetime64[ns] dask.array<chunksize=(838,), meta=np.ndarray>
    longitude       (atrack, xtrack) float32 dask.array<chunksize=(838, 1259), meta=np.ndarray>
    latitude        (atrack, xtrack) float32 dask.array<chunksize=(838, 1259), meta=np.ndarray>
    incidence       (atrack, xtrack) float32 dask.array<chunksize=(838, 1259), meta=np.ndarray>
    elevation       (atrack, xtrack) float32 dask.array<chunksize=(838, 1259), meta=np.ndarray>
    sigma0_raw      (pol, atrack, xtrack) float64 dask.array<chunksize=(2, 838, 1259), meta=np.ndarray>
    nesz            (pol, atrack, xtrack) float32 dask.array<chunksize=(2, 838, 1259), meta=np.ndarray>
    gamma0_raw      (pol, atrack, xtrack) float64 dask.array<chunksize=(2, 838, 1259), meta=np.ndarray>
    negz            (pol, atrack, xtrack) float32 dask.array<chunksize=(2, 838, 1259), meta=np.ndarray>
    sigma0          (pol, atrack, xtrack) float64 dask.array<chunksize=(2, 838, 1259), meta=np.ndarray>
    gamma0          (pol, atrack, xtrack) float64 dask.array<chunksize=(2, 838, 1259), meta=np.ndarray>
Attributes:
    footprint:       POLYGON ((-67.84221143971432 20.72564283093837, -70.2216...
    coverage:        251km * 170km (xtrack * atrack )
    pixel_xtrack_m:  10.0
    pixel_atrack_m:  10.2
    ipf_version:     2.84
    swath_type:      IW
    polarizations:   VV VH
    product_type:    GRD
    mission:         SENTINEL-1
    satellite:       A
    start_date:      2017-09-07 10:30:20.936409
    stop_date:       2017-09-07 10:30:45.935264
    path:            /home/alevieux/Documents/Data/S1A_IW_GRDH_1SDV_20170907T...
    denoised:        {'VH': False, 'VV': False}
    subdataset:      IW
    geometry:        {'VH': {'atrack':   atracks xtracks                     ...
    Conventions:     CF-1.7

rasterize(hv.Image(
            sar_ds_200m.sigma0.sel(pol='VV')
            ).opts(clim=(0,0.4), cmap='gray',colorbar=True,tools=['hover'],title="xsar"))