ukis_pysat.raster

class ukis_pysat.raster.Image(data, dimorder='first', crs=None, transform=None, nodata=None)

Bases: object

Parameters:
  • data – rasterio.io.DatasetReader or path to raster or np.ndarray of shape (bands, rows, columns)
  • dimorder – Order of channels or bands ‘first’ or ‘last’ (default: ‘first’)
  • crs – Coordinate reference system used when creating form array. If ‘data’ is np.ndarray this is required (default: None)
  • transform – Affine transformation mapping the pixel space to geographic space. If ‘data’ is np.ndarray this is required (default: None)
  • nodata – nodata value only used when creating from np.ndarray, otherwise this has no effects, optional (default: None)
arr

array property

close()

closes Image

da_arr = None
dn2toa(platform, mtl_file=None, wavelengths=None)

This method converts digital numbers to top of atmosphere reflectance, like described here: https://www.usgs.gov/land-resources/nli/landsat/using-usgs-landsat-level-1-data-product

Parameters:
  • platform – image platform, possible Platform.Landsat[5, 7, 8] or Platform.Sentinel2 (<enum ‘Platform’>).
  • mtl_file – path to Landsat MTL file that holds the band specific rescale factors (str).
  • wavelengths – like [“Blue”, “Green”, “Red”, “NIR”, “SWIR1”, “TIRS”, “SWIR2”] for Landsat-5 (list of str).
get_subset(tile, band=0)

Get slice of array.

Parameters:
  • tile – rasterio.windows.Window tile from get_tiles().
  • band – Band number (default: 0).
Returns:

Sliced numpy array, bounding box of array slice.
get_tiles(width=256, height=256, overlap=0)

Calculates rasterio.windows.Window, idea from https://stackoverflow.com/a/54525931

Parameters:
  • width – int, optional (default: 256). Tile size in pixels.
  • height – int, optional (default: 256). Tile size in pixels.
  • overlap – int, optional (default: 0). Overlap in pixels.
Yields:

window of tile
get_valid_data_bbox(nodata=0)

bounding box covering the input array’s valid data pixels.

Parameters:nodata – nodata value, optional (default: 0)
Returns:tuple with valid data bounds
mask(bbox, crop=True, fill=False, mode='constant', constant_values=0)

Mask raster to bbox.

Parameters:
  • bbox – bounding box of type tuple or Shapely Polygon
  • crop – bool, see rasterio.mask. Optional, (default: True)
  • fill – enforce raster to cover bbox. if raster extent is smaller than bbox it will be filled according to mode and constant_values parameters. Optional (default: False)
  • mode – str, how to fill, see rasterio.pad. Optional (default: ‘constant’)
  • constant_values – nodata value, padding should be filled with, optional (default: 0)
pad(pad_width, mode='constant', constant_values=0)

Pad raster in all directions.

Parameters:
  • pad_width – pad width in pixels, int.
  • mode – str, how to pad, see rasterio.pad. Optional (default: ‘constant’)
  • constant_values – nodata value, padding should be filled with, optional (default: 0)
Returns:

closed, buffered dataset in memory
to_dask_array(chunk_size=(1, 6000, 6000))

transforms numpy to dask array

Parameters:chunk_size – tuple, size of chunk, optional (default: (1, 6000, 6000))
Returns:dask array
warp(dst_crs, resampling_method=0, num_threads=4, resolution=None, nodata=None, target_align=None)

Reproject a source raster to a destination raster.

Parameters:
  • dst_crs – CRS or dict, Target coordinate reference system.
  • resampling_method – Resampling algorithm, int, defaults to 0 (Nearest) numbers: https://github.com/mapbox/rasterio/blob/master/rasterio/enums.py#L28
  • num_threads – int, number of workers, optional (default: 4)
  • resolution – tuple (x resolution, y resolution) or float, optional. Target resolution, in units of target coordinate reference system.
  • target_align – raster to which to align resolution, extent and gridspacing, optional (Image).
  • nodata – nodata value of source, int or float, optional.
write_to_file(path_to_file, dtype, driver='GTiff', nodata=None, compress=None, kwargs=None)

Write a dataset to file. :param path_to_file: str, path to new file :param dtype: datatype, like np.uint16, ‘float32’ or ‘min’ to use the minimum type to represent values

Parameters:
  • driver – str, optional (default: ‘GTiff’)
  • nodata – nodata value, e.g. 255 (default: None, means nodata value of dataset will be used)
  • compress – compression, e.g. ‘lzw’ (default: None)
  • kwargs – driver specific keyword arguments, e.g. {‘nbits’: 1, ‘tiled’: True} for GTiff (default: None) for more keyword arguments see gdal driver specifications, e.g. https://gdal.org/drivers/raster/gtiff.html