This software produces cutouts from FITS images.
- CFITSIO - library to read and write FITS files.
- AST -- library to handle worl coordinate systems and image transformation
- OpenMP -- a gcc compiler with openmp support
The basic usage to extract a cutout from an image is
cutout image.fit cutout.hdr cutout.fit
where image.fit is the image to extract the cutout from and cutout.hdr contains the header of the desired extracted cutout provided by the user, e.g.
BITPIX = -32 / number of bits per data pixel
NAXIS = 2 / number of data axes
NAXIS1 = 175 / length of data axis 1
NAXIS2 = 175 / length of data axis 2
CRVAL1 = 157.010000 / Reference value on 1st axis in primary WCS
CRVAL2 = -19.271000 / Reference value on 2nd axis in primary WCS
CRPIX1 = 87.500000 / Reference pixel on 1st axis in primary WCS
CRPIX2 = 87.500000 / Reference pixel on 2nd axis in primary WCS
CD1_1 = -9.479372e-05 / Transformation matrix for primary WCS
CD2_2 = 9.479372e-05 / Transformation matrix for primary WCS
CTYPE1 = 'RA---TAN' / &
CTYPE2 = 'DEC--TAN' / &
RADESYS = 'ICRS ' / Reference frame for RA/DEC values
To extract multiple cutouts one can do
cutout driver
where driver is a text file containing one line per desired cutout, e.g.
image.fit[1] cutout1.hdr cutout1.fit
image.fit[1] cutout2.hdr cutout2.fit
image.fit[2] cutout3.hdr cutout3.fit
Note that image extensions have to be specified (unless the image contains a single extension). In this case cutout makes use of the multiprocessor architectore and makes the cutouts in parallel using the available number of CPUs or the ones set by the environment variable OMP_NUM_THREADS,
env OMP_NUM_THREADS=4 cutout driver
with example output:
Number of processors available = 12
Number of threads = 4
Processor 0 : o20131211_00044.fit[8] -> !faaf25c3751c930362542af6535aa074.fit
Processor 2 : o20131211_00045.fit[8] -> !bfa9e66fac18cea336f5c7b3c13cf9de.fit
Processor 1 : o20131211_00052.fit[8] -> !51eadf5cd3359f94d8ac1787c5cebf4e.fit
Processor 3 : o20131211_00058.fit[8] -> !a103afa15ddc1f4cb182c7fa63e026c2.fit
Processor 2 : o20140221_00048.fit[8] -> !bdde9d7b61a9170a97a8cb56e9c29238.fit
Processor 0 : o20140221_00049.fit[21] -> !62374224036691df973143bafa2b2091.fit
Processor 1 : o20140221_00055.fit[8] -> !511f7afec4d6d9c0be73a51cac068098.fit
Processor 3 : o20140221_00056.fit[8] -> !f80541da80714a93ad32a14cf0c10971.fit
Processor 0 : o20140221_00057.fit[21] -> !20ebdf286498406a3bb47df6ef5cbf40.fit
Processor 2 : o20140221_00063.fit[8] -> !98b9613779bef8255013a0a56e9c358f.fit
Processor 1 : o20140221_00064.fit[21] -> !56cda30fdc0fb57269470d918574d88a.fit
- see LICENSE file.