Module pytools4dart.tools.hstools

This module contains the functions to stasck simulated bands into an ENVI HDR file. It allows to read .hdr file and returns a dictionary.

Functions

gdal_drivers

def gdal_drivers(

)

List of available GDAL drivers with there corresponding
default extension (ext), possible extensions (exts) and
GDAL writable capacity (writable).

https://gdal.org/drivers/raster/index.html

Returns
-------
pandas.DataFrame

gdal_file

def gdal_file(
    file,
    driver
)

Check driver is writable and if extension is one expected by gdal.
If not it is replaced by the default extension of gdal driver.
If the default extension is not defined, then the driver name in lower case is taken instead.

Parameters
----------
file: str
    path to file
driver: str
    A driver name, see pytools4dart.hstools.gdal_drivers().

Returns
-------
str

get_hdr_bands

def get_hdr_bands(
    hdr,
    nm_to_um=True
)

Extract band specifications from .hdr file.

Parameters
----------
hdr: DataFrame
    in the format given by function read_ENVI_hdr.
nm_to_um: bool
    to convert wavelengths and bandwidth from nm and µm,
    which are the default units for wavelengths in ENVI files and DART respectively

Returns
-------

get_wavelengths

def get_wavelengths(
    phasefile
)

Get the band wavelength values of a simulation.

Parameters
----------
phasefile: str
    path to the input phase.xml file of DART simulation.

Returns
-------
: DataFrame
    band number, wavelength, full width at half maximum.

normalize

def normalize(
    array
)

Normalize array: (array-min)/(max-min)
Parameters
----------
array: numpy.ndarray

Returns
-------
numpy.ndarray

read_ENVI_hdr

def read_ENVI_hdr(
    path,
    dartlabels=False
)

Read hyperspectral ENVI file header

Parameters
----------
path: str
    Path to .hdr file.
dartlabels: bool
    ???

Returns
-------

rotate_raster

def rotate_raster(
    src_file,
    dst_file
)

Rotate raster to a more standard GIS orientation

DART has the following axis specific convention:

    o -- y+

    :

    x+

Thus the image are converted to a more standard raster definition:

    y+

    :

    o -- x+

Parameters
----------
src_file: str
dst_file: str

Examples
--------

>>> import pytools4dart as ptd
>>> import rasterio as rio
>>> from rasterio.plot import show
>>> import matplotlib.pyplot as plt
>>> simu = ptd.simulation('use_case_6') #doctest:+ELLIPSIS
Loading plot file: ...use_case_6/input/plots.txt
Updating plot file properties index...
Updating plot file properties name...
>>> bandlist = ptd.hstools.get_bands_files(simu.output_dir)
>>> raster_file = bandlist.loc[(bandlist.azimuth==0) & (bandlist.band_num==0), 'path'].iloc[0]
>>> rotated_file = '/tmp/raster_rotate.mpr'
>>> ptd.hstools.rotate_raster(raster_file, rotated_file)
>>> r = rio.open(raster_file)
>>> rr = rio.open(rotated_file)
>>> print([rr.width, rr.height] == [r.height, r.width])
True
>>> print(rr.transform[4] == -r.transform[0])
True
>>> print(rr.transform[5] == r.transform[2] + r.width * r.transform[0])
True

stack_dart_bands

def stack_dart_bands(
    band_files,
    outputfile,
    driver='ENVI',
    rotate=True,
    wavelengths=None,
    fwhm=None,
    verbose=False
)

Stack simulated bands into an ENVI file.

Parameters
----------
band_files: list
    list of DART file paths to stack into the output ENVI file.
outputfile: str
    file path to be written. Output format is ENVI thus file should be with .bil extension.
driver: str
    GDAL driver, see pytools4dart.hstools.gdal_drivers().
    If driver='ENVI' it adds the wavelength and bandwidth of bands to the .hdr file.
rotate: bool
    rotate bands from DART orientation convention to a standard GIS orientation convention.
    See pytools4dart.hstools.rotate_raster for details.
wavelengths: list
    list of wavelength values (in nm) corresponding to the bands (in the same order).
    They will be written in .hdr file.
fwhm: list
    list of Full Width at Half Maximum (in nm) corresponding to the bands (in the same order).
    They will be written in .hdr file.
verbose: bool
    if True, it gives a message when files are written.

Returns
-------