In this page you can download the drizzling software library, which reprojects data from HEALPix to local WCS, in IDL and Python languages. The drizzling library uses a strategy where the surface of pixel intersection is computed as presented in Appendix A of Paradis et al., 2012, A&A, 543, 103. This method allows fast ingestion and guarantees the photometric accuracy of the transformation with minimal data loss during the transformation from HEALPix to local WCS FITS.

NEW You can now access a web interface to reproject data from HEALPix to local WCS http://drizzweb.irap.omp.eu/

• Jean-Philippe Bernard (IRAP)
• Nathalie Baby (IRAP)
• Caroline Bot (CDS)
• Laurent Cambrésy (CDS)
• Déborah Paradis (IRAP)
• Alexandre Sauvé (IRAP)

Download : drizzlib_v08_15_beta.zip

• Antoine Goutenoir (IRAP)
• Déborah Paradis (IRAP)
• Jean-Michel Glorian (IRAP)
• Gabriel Foënard (IRAP)

The source tree is available on gitlab.

The python package itself can be downloaded via pip :

pip install drizzlib

Or you can directly grab a tarball here :

* drizzlib-1.2.6.2.tar.gz (2018-11-16)

• drizzlib-1.2.6.1.tar.gz (2018-10-16)
• drizzlib-1.2.5.tar.gz (2018-05-25)
• drizzlib-1.2.2.tar.gz (2017-05-17)
• drizzlib-1.0.1.tar.gz (2015-12-18)

There are detailed instructions and troubleshooting tips in the README, which you should read.

First, install the system dependencies :

Debian / Ubuntu

apt-get install python-dev pkg-config libfreetype* gfortran libopenblas-dev liblapack-dev

pip install drizzlib

It may complain about numpy. Install it, and try again.

Uncompress the tarball, move into it.

Then, install the python dependencies using pip :

pip install --upgrade setuptools
pip install -r requirements.txt

Finally, install drizzlib itself :

python setup.py install

Here's a simple usage example, that reads my_healpix.fits and extracts a subset of its data as described by the header in wcs_config.fits, and writes the result into my_wcs.fits :

from drizzlib import healpix2wcs
 
healpix2wcs(
    'my_healpix.fits',
    header='wcs_config.fits',
    output='my_wcs.fits'
)

You can write to cade@irap.omp.eu.