ost.helpers.raster

Helper functions for raster data

Functions

calc_max
calc_min
combine_timeseries
convert_to_db	Convert array of SAR power to decibel
create_rgb_jpeg	param filelist
create_timeseries_animation
create_tscan_vrt
fill_internal_nans	Function that fills no-data values with interpolation
get_max
get_min
image_bounds	Function to create a polygon of image boundary
mask_by_shape	Mask a raster layer with a vector file (including data conversions)
norm	Normalize array by its min/max or 2- and 98 percentile
outline	Generates a vector file with the valid areas of a raster file
polygonize_bounds	Polygonize a raster mask based on a mask value
polygonize_ls
rescale_to_float	Re-convert a previously converted integer array back to float
scale_to_int	Convert a float array to integer by linear scaling between min and max
stretch_to_8bit
visualise_rgb	param filepath

ost.helpers.raster.calc_max(band, stretch='minmax')

ost.helpers.raster.calc_min(band, stretch='minmax')

ost.helpers.raster.combine_timeseries(processing_dir, config_dict, timescan=True)

ost.helpers.raster.convert_to_db(pow_array)

Convert array of SAR power to decibel

Parameters

pow_array –

Returns

ost.helpers.raster.create_rgb_jpeg(filelist, outfile=None, shrink_factor=1, resampling_factor=5, plot=False, date=None, filetype=None)

Parameters

• filelist –

• outfile –

• shrink_factor –

• resampling_factor – 5 is average

• plot –

• date –

• filetype –

Returns

ost.helpers.raster.create_timeseries_animation(timeseries_folder, product_list, out_folder, shrink_factor=1, resampling_factor=5, duration=1, add_dates=False, prefix=False)

ost.helpers.raster.create_tscan_vrt(timescan_dir, config_file)

ost.helpers.raster.fill_internal_nans(array)

Function that fills no-data values with interpolation

Parameters

array –

Returns

ost.helpers.raster.get_max(file, dtype='float32')

ost.helpers.raster.get_min(file, dtype='float32')

ost.helpers.raster.image_bounds(data_dir)

Function to create a polygon of image boundary

This function for all files within a dimap data directory

Parameters

data_dir –

Returns

ost.helpers.raster.mask_by_shape(infile, outfile, vector, to_db=False, datatype='float32', rescale=True, min_value=1e-06, max_value=1, ndv=None, description=True)

Mask a raster layer with a vector file (including data conversions)

Parameters

• infile –

• outfile –

• vector –

• to_db –

• datatype –

• rescale –

• min_value –

• max_value –

• ndv –

• description –

Returns

ost.helpers.raster.norm(array, percentile=False)

Normalize array by its min/max or 2- and 98 percentile

Parameters

• array –

• percentile –

Returns

ost.helpers.raster.outline(infile, outfile, ndv=0, less_then=False, driver='GeoJSON')

Generates a vector file with the valid areas of a raster file

Parameters

• infile – input raster file

• outfile – output shapefile

• ndv – no-data-value

• less_then –

• driver –

Returns

ost.helpers.raster.polygonize_bounds(infile, outfile, mask_value=1, driver='GeoJSON')

Polygonize a raster mask based on a mask value

Parameters

• infile –

• outfile –

• mask_value (int/float, optional) –

• driver (str, optional) –

Returns

ost.helpers.raster.polygonize_ls(infile, outfile, driver='GeoJSON')

ost.helpers.raster.rescale_to_float(int_array, data_type)

Re-convert a previously converted integer array back to float

Parameters

• int_array –

• data_type –

Returns

ost.helpers.raster.scale_to_int(float_array, min_value, max_value, data_type)

Convert a float array to integer by linear scaling between min and max

Parameters

• float_array –

• min_value –

• max_value –

• data_type –

Returns

ost.helpers.raster.stretch_to_8bit(file, layer, dtype, aut_stretch=False)

ost.helpers.raster.visualise_rgb(filepath, shrink_factor=25)

Parameters

• filepath –

• shrink_factor –

Returns