Tibeuleu/FOC_Reduction
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

fix WCS computation when importing fits

Browse Source
This commit is contained in:
Thibault Barnouin
2025-04-10 18:14:38 +02:00
parent 3c321a7724
commit 278a31beab
2 changed files with 55 additions and 32 deletions
Download Patch File Download Diff File Expand all files Collapse all files

42
package/lib/fits.py
View File

@@ -16,7 +16,7 @@ from astropy.io import fits
from astropy.wcs import WCS
from .convex_hull import clean_ROI
from .utils import wcs_PA
from .utils import wcs_CD_to_PC, wcs_PA
def get_obs_data(infiles, data_folder="", compute_flux=False):
@@ -61,26 +61,30 @@ def get_obs_data(infiles, data_folder="", compute_flux=False):
for i in range(len(data_array)):
data_array[i][data_array[i] < 0.0] = 0.0
# force WCS to convention PCi_ja unitary, cdelt in deg
# Compute CDELT, ORIENTAT from header
for wcs, header in zip(wcs_array, headers):
new_wcs = wcs.deepcopy()
if new_wcs.wcs.has_cd() or (new_wcs.wcs.cdelt[:2] == np.array([1.0, 1.0])).all():
# Update WCS with relevant information
if new_wcs.wcs.has_cd():
del new_wcs.wcs.cd
keys = list(new_wcs.to_header().keys()) + ["CD1_1", "CD1_2", "CD1_3", "CD2_1", "CD2_2", "CD2_3", "CD3_1", "CD3_2", "CD3_3"]
for key in keys:
header.remove(key, ignore_missing=True)
new_cdelt = np.linalg.eigvals(wcs.wcs.cd)
# new_cdelt.sort()
new_wcs.wcs.pc = wcs.wcs.cd.dot(np.diag(1.0 / new_cdelt))
new_wcs.wcs.cdelt = new_cdelt
for key, val in new_wcs.to_header().items():
header[key] = val
try:
header["ORIENTAT"] = float(header["ORIENTAT"])
except KeyError:
header["ORIENTAT"] = wcs_PA(new_wcs.wcs.pc[1, 0], np.diag(new_wcs.wcs.pc).mean())
if new_wcs.wcs.has_cd():
del new_wcs.wcs.cd
keys = list(new_wcs.to_header().keys()) + ["CD1_1", "CD1_2", "CD1_3", "CD2_1", "CD2_2", "CD2_3", "CD3_1", "CD3_2", "CD3_3"]
for key in keys:
header.remove(key, ignore_missing=True)
cdelt, orient = wcs_CD_to_PC(wcs.wcs.cd)
new_wcs.wcs.pc = wcs.wcs.cd.dot(np.diag(1.0 / cdelt))
new_wcs.wcs.cdelt = cdelt
try:
header["ORIENTAT"] = float(header["ORIENTAT"])
except KeyError:
header["ORIENTAT"] = -orient
elif new_wcs.wcs.has_pc() and (new_wcs.wcs.cdelt[:2] != np.array([1.0, 1.0])).all():
try:
header["ORIENTAT"] = float(header["ORIENTAT"])
except KeyError:
header["ORIENTAT"] = -wcs_PA(new_wcs.wcs.pc, new_wcs.wcs.cdelt)
else:
print("Could not compute ORIENTAT or CDELT from WCS")
for key, val in new_wcs.to_header().items():
header[key] = val
# force WCS for POL60 to have same pixel size as POL0 and POL120
is_pol60 = np.array([head["filtnam1"].lower() == "pol60" for head in headers], dtype=bool)