Changes between Initial Version and Version 1 of pswarp

Timestamp:

May 9, 2013, 11:09:57 AM (13 years ago)

Author:

eugene

Comment:

--

pswarp

@@ +1 @@
+== pswarp ==
+
+(Up to the [wiki:IPP_Description IPP Description Page])
+
+pswarp invocation (single input exposure set):
+
+{{{
+pswarp -file input.fits output skycell                    : input.fits must define the astrometry of the input pixels, skycell defines target astrometry.
+pswarp -file input.fits -astrom astrom.cmf output skycell : astrom.cmf defines astrometry for input.fits
+}}}
+
+pswarp invocation (multiple inputs):
+{{{
+pswarp -input file.mcd output skycell                     : input files are defined in the file.mdc 
+}}}
+
+Example of input.mdc:
+{{{
+INPUT MULTI
+
+INPUT METADATA
+  INPUT     STR   RINGS.V3.skycell.1314.011.stk.1033022.fits   # signal image filename
+  MASK      STR   RINGS.V3.skycell.1314.011.stk.1033022.mask.fits   # signal image filename
+  VARIANCE  STR   RINGS.V3.skycell.1314.011.stk.1033022.wt.fits   # signal image filename
+END
+
+INPUT METADATA
+  INPUT     STR   RINGS.V3.skycell.1314.012.stk.1033023.fits   # signal image filename
+  MASK      STR   RINGS.V3.skycell.1314.012.stk.1033023.mask.fits   # signal image filename
+  VARIANCE  STR   RINGS.V3.skycell.1314.012.stk.1033023.wt.fits   # signal image filename
+END
+}}}
+
+pswarp outline
+
+* generic initializations
+* pswarpArguments      : parse the command line arguments
+* pswarpParseCamera    : examine the input files and skycell, construct containers for the outputs (do not yet generate pixels)
+* pswarpOptions        : set various options which may depend on the camera and command line arguments
+* pswarpDefineLayout   : load astrometry information (headers only), determine the overlaps between the inputs and the outputs, generate the output pixels
+* pswarpLoop           : loop over inputs & outputs, warp the inputs into the outputs, transform the input sources (if any), measure the new PSF model, convert input metadata to output metadata values
+* pswarpLoopBackground : equivalent to pswarpLoop, transform the background models
+* pswarpCleanup        : write the outputs to disk, free memory
+
+NOTE: as of 2013.05.09 there has been a substantial re-work of pswarp to enable 'inverse warping', that is to say warping from skycells to the original focal plane.  This modification drove a few specific changes:
+
+* the output format may now represent a full FPA output file (with chips and cells, etc).  
+* there may now be multiple input 'exposures' (more accurately: file sets) so that a group of skycells can be warped to a single output image
+* the astrometric relationships / overlaps are calculated up front (in pswarpDefineLayout) before any pixels are loaded.  This is necessary to avoid generating the output pixels in (for example) a full GPC1 FPA if only a few of the output pixels are needed.
+* the input files may now be specified in a metadata config file as illustrated above (similar to the inputs to ppStack & psphotStack).
+
+There are effectively 3 modes of operation : chip-to-warp (the traditional mode), chip-to-chip, and warp-to-chip.