Drizzlepac

===================

- Fix problems with testing code for this package [940]

==================

This version provides the first operational implementation of the single-visit
mosaic processing used to create the single-visit mosaics products.

- revise naming convention for the StaticMask file so that it has a
dataset-specific name instead of a generic common name. [876]

- Update ``runastrodriz`` to work under Windows while adding documentation
to tell the user to run with ``num_cores`` set to 1. [794]

- Fixed a bug in ``TweakReg`` due to which ``TweakReg`` would crash when
``updatehdr`` was set to `False`. [801]

===================

A number of changes have been implemented to either correct problems or
improve the processed results. The most significant of the changes are:

- rscale only used for alignment.
- a minimum of 6 sources now gets used for alignment
- no proper motions used in astrometric (GAIA) catalog when attempting a posteriori fitting
- chip-to-chip alignment errors were corrected


In addition to a few dozen bug fixes, the following updates to the algorithms
were also implemented.

- Simplified the logic in ``tweakreg`` for deciding how to archive primary WCS
resulting in a reduction of duplicate WCSes in image headers. [715]

- Added polynomial look-up table distortion keywords to the list of distortion
keywords used by ``outputimage.deleteDistortionKeywords`` so that
distortions can be removed from ACS images that use ``NPOLFILE``.
This now allows removal of alternate WCS from blotted image headers. [709]

- Added ``rules_file`` parameter to AstroDrizzle to enable use of custom
files in pipeline processing. [674]

- Only apply solutions from the astrometry database which were non-aposteriori
WCS solutions as the PRIMARY WCS. This allows the pipeline to compare the
true apriori WCS solutions (e.g., GSC or HSC WCSs) to aposteriori solutions
computed using the latest distortion-models and alignment algorithms being
used at the time of processing. [669]

- Verification using a similarity index gets reported in the trailer file and
does not get used as a Pass/Fail criteria for alignment. [619]

- If verification fails for either pipeline-default or apriori solution, reset
cosmic-ray(CR) flag (4096) in DQ arrays. This will allow subsequent attempt to
align the images to not be impacted by potentially mis-identified CRs that most
likely blanked out real sources in the field. As a result, the image alignment
process became more robust when computing the aposteriori alignment. [614]

- Fix a crash in ``tweakreg`` when finding sources in very large images
due to a bug in ``scipy.signal.convolve2d``. [670]

- Fix a bug in ``tweakreg`` due to which the number of matched sources needed to be
*strictly* greater than ``minobj``. Now the minimum number of matched sources
maust be *at least* equal or greater than ``minobj``. [604]

- Fix a crash in ``tweakreg`` when ``2dhist`` is enabled and ``numpy``
version is ``1.18.1`` and later. [583, 587]

- Update calibrated (FLC/FLT) files with RMS and NMATCH keywords when it successfully
aligns the data to GAIA using the a posteriori fit. Headerlet files for this fit
which already have these keywords are now retained and provided as the final output
headerlets as well. [555]

- Insure HDRNAME keyword gets added to successfully aligned FLC/FLT files. [580]

- Fix problem with 'tweakback' task when trying to work with updated WCS names. [551]

- Fix problems found in processing data with NGOODPIX==0, DRC files not getting
generated for singletons, alignment trying to use a source too near the chip edge,
catch the case were all inputs have zero exposure time, lazily remove alignment
sub-directories, fixed a bug in overlap computation that showed up in oblong mosaics,
recast an input to histogram2d as int, defined default values for tables when no
sources were found. [593]

- Updated to be compatible with tweakwcs v0.6.0 to correct chip-to-chip alignment issues
in aposteriori WCS solutions. [596]

- Correctly define output drizzle product filename during pipeline processing
for exposures with 'drz' in the rootname. [523]

- Implement multiple levels of verification for the drizzle products generated
during pipeline processing (using runastrodriz); including overlapp difference
computations [520], and magnitude correlation [512].

- Replace alignimages module with O-O based align [512]

- Fix problem with NaNs when looking for sources to use for aligning images [512]

- Fixed code that selected the brightest sources to use for alignment allowing
alignment to work (more often) for images with saturated sources. [512]

- Use logic for defining the PSF extracted from the images to shrink it in each
axis by one-half for images of crowded fields to allow for more sources to be
extracted by daofind-like algorithm. This enables source finding and alignment
to work more reliably on crowded field images. [512]

- Insure all input files, especially those with zero exposure time or grism
images, get updated with the latest pipeline calibration for the distortion. [ 495]

This version also relies on updates in the following packages to get correctly
aligned and combined images with correctly specified WCS keywords:

- TWEAKWCS 0.6.4: This version corrects problems with the chip-to-chip separation
that arose when applying a single fit solution to the entire observation.

- STWCS 1.5.4: This version implements a couple of fixes to insure that use of
headerlets defines the full correct set of keywords from the headerlet for
the PRIMARY WCS in the science exposure without introducing multiple copies of
some keywords.

- Numpy 1.18: Changes in numpy data type definitions affected some of the code used
for computing the offset between images when performing aposteriori alignment
during pipeline processing and when running the 'tweakreg' task.

==================

- Fixed a bug in the ``updatehdr.update_from_shiftfile()`` function that would
crash while reading shift files. [448]

- Migration of the HAP portion of the package to an object-oriented
implemenation. [427]

- Added support for providing HSTWCS object as input to 'final_refimage'
or 'single_refimage' parameter. [426]

- Implementation of grid definition interface to support returning SkyCell
objects that overlap a mosaic footprint. [425]

- Complete rewrite of ``runastrodriz`` for pipeline processing to include
multi-level verification of alignment. [440]

====================

- Removed deprecated parameter ``coords`` from the parameter list of
``pixtopix.tran()`` function. [406]

- Modified the behavior of the ``verbose`` parameter in ``pixtopix.tran()``
to not print coordinates when not run as a script and when ``output``
is `None`. [406]

- Fixed a compatibility issue in ``tweakutils`` that would result in crash in
``skytopix`` when converting coordinates in ``hms`` format. [385]

- Fixed a bug in the ``astrodrizzle.sky`` module due to which sky matching
fails with "Keyword 'MDRIZSKY' not found" error when some of the
input images do not overlap at all with the other images. [380]

- Fixed a bug in the ``util.WithLogging`` decorator due to which incorrect
log file was reported when user-supplied log file name does not have ``.log``
extension. [365]

- Fixed a bug introduced in 364 returning in ``finally`` block. [365]

- Improved ``util.WithLogging`` decorator to handle functions that return
values. [364]

- Fixed a bug in the automatic computation of the IVM weights when IVM
was not provided by the user. [320]

- Fixed a bug in the 2D histogram code used for estimating shifts for
catalog pre-matching. This may result in better matching. [286]

- Now ``tolerance`` (in ``tweakreg``) is no longer ignored when ``use2dhist``
is enabled. [286]

- Fixed VS compiler errors with pointer artithmetic on void pointers. [273]

- Fix logic so that code no longer tries to update headers when no valid fit
could be determined. [241]

- Fixed a bug in the computation of interpolated large scale flat field
for STIS data. The bug was inconsequential in practice.
Removed the dependency on ``stsci.imagemanip`` package. [227]

- Removed the dependency on ``stsci.ndimage`` (using ``scipy`` routines
instead). [225]

- Added ``'Advanced Pipeline Products'`` alignment code to ``drizzlepac``
package. Enhance ``runastrodriz`` to compute and apply absolute astrometric
corrections to GAIA (or related) frame to images where possible.
[200, 213, 216, 223, 234, 235, 244, 248, 249, 250, 251,
259, 260, 268, 271, 283, 294, 302]

- Add computation and reporting of the fit's
`Root-Mean-Square Error (RMSE) <https://en.wikipedia.org/wiki/Root-mean-square_deviation>`_
and `Mean Absolute Error (MAE) <https://en.wikipedia.org/wiki/Mean_absolute_error>`_.
[210]

- Replaced the use of ``WCS._naxis1`` and ``WCS._naxis2`` with
``WCS.pixel_shape`` [207]

- Removed support for Python 2. Only versions >= 3.5 are supported. [207]

- Use a more numerically stable ``numpy.linalg.inv`` instead of own matrix
inversion. [205]

- The intermediate fit match catalog, with the name ``_catalog_fit.match``
generated by ``tweakreg`` now has correct RA and DEC values for the sources
after applying the fit. [200, 202]

- Simplify logic for determining the chip ID for each source. [200]

===================

- Fix a bug that results in ``tweakreg`` crashing when no sources are found
with user-specified source-finding parameters and when ``tweakreg`` then
attempts to find sources using default parameters. [181]

- Updated unit_tests to use original inputs, rather than updated inputs used by
nightly regression tests.

- Fix ``numpy`` "floating" deprecation warnings. [175]

- Fix incorrect units in CR-cleaned images created by ``astrodrizzle``. Now
CR-cleaned images should have the same units as input images. [190]