def _project_reference_hdu(self, name_hdr, muse_hdu=None):
"""Project the reference image onto the MUSE field
"""
if self.use_montage:
# The original way. Sometimes this introduces an offset
hdu_repr = montage.reproject_hdu(self.reference_hdu,
header=name_hdr,
exact_size=True)
else:
# The mpdaf way
if muse_hdu is not None:
wcs_ref = WCS(hdr=self.reference_hdu.header)
ima_ref = Image(data=self.reference_hdu.data, wcs=wcs_ref)
wcs_muse = WCS(hdr=muse_hdu.header)
ima_muse = Image(data=muse_hdu.data, wcs=wcs_muse)
ima_ref = ima_ref.align_with_image(ima_muse)
hdu_repr = ima_ref.get_data_hdu()
else:
hdu_repre = None
print(
"Warning: provide target HDU when not using montage to reproject"
)
return hdu_repr
def rotate_cube_wcs(cube_name,
cube_folder="",
outwcs_folder=None,
rotangle=0.,
**kwargs):
"""Routine to remove potential Nan around an image and reconstruct
an optimal WCS reference image. The rotation angle is provided as a way
to optimise the extent of the output image, removing Nan along X and Y
at that angle.
Args:
cube_name (str): input image name. No default.
cube_folder (str): input image folder ['']
outwcs_folder (str): folder where to write the output frame. Default is
None which means that it will use the folder of the input image.
rotangle (float): rotation angle in degrees [0]
**kwargs:
in_suffix (str): in suffix to remove from name ['prealign']
out_suffix (str): out suffix to add to name ['rotwcs']
margin_factor (float): factor to extend the image [1.1]
Returns:
"""
# Reading the input names and setting output folder
fullname = joinpath(cube_folder, cube_name)
cube_folder, cube_name = os.path.split(fullname)
if outwcs_folder is None:
outwcs_folder = cube_folder
# Suffix
in_suffix = kwargs.pop("in_suffix", "prealign")
out_suffix = kwargs.pop("out_suffix", "rotwcs")
# Get margin if needed
margin_factor = kwargs.pop("margin_factor", 1.1)
extend_fraction = np.maximum(0., (margin_factor - 1.))
upipe.print_info("Will use a {:5.2f}% extra margin".format(
extend_fraction * 100.))
# Opening the image via mpdaf
cubewcs = Cube(fullname)
imawcs = cubewcs.sum(axis=0)
extra_pixels = (np.array(imawcs.shape) * extend_fraction).astype(np.int)
# New dimensions and extend current image
new_dim = tuple(np.array(imawcs.shape).astype(np.int) + extra_pixels)
ima_ext = imawcs.regrid(newdim=new_dim,
refpos=imawcs.get_start(),
refpix=tuple(extra_pixels / 2.),
newinc=imawcs.get_step()[0] * 3600.)
# Copy and rotate WCS
new_wcs = copy.deepcopy(ima_ext.wcs)
upipe.print_info(
"Rotating spatial WCS of Cube by {} degrees".format(rotangle))
new_wcs.rotate(rotangle)
# New rotated image
ima_rot = Image(data=np.nan_to_num(ima_ext.data), wcs=new_wcs)
# Then resample the image using the initial one as your reference
ima_rot_resampled = ima_rot.align_with_image(ima_ext, flux=True)
# Crop NaN
ima_rot_resampled.crop()
# get the new header with wcs and rotate back
finalwcs = ima_rot_resampled.wcs
finalwcs.rotate(-rotangle)
# create the final image
data_cube_rot = np.repeat(ima_rot_resampled[np.newaxis, :, :].data,
cubewcs.shape[0],
axis=0)
final_rot_cube = Cube(data=data_cube_rot, wave=cubewcs.wave, wcs=finalwcs)
# Save image
if isinstance(in_suffix,
str) and in_suffix != "" and in_suffix in cube_name:
out_name = cube_name.replace(in_suffix, out_suffix)
else:
name, extension = os.path.splitext(cube_name)
if out_suffix != "":
out_suffix = "_{}".format(out_suffix)
out_name = "{0}{1}{2}".format(name, out_suffix, extension)
# write output
final_rot_cube.write(joinpath(outwcs_folder, out_name))
return outwcs_folder, out_name