Документ взят из кэша поисковой машины. Адрес оригинального документа : http://xmm.vilspa.esa.es/sas/7.1.0/doc/omcomb.ps.gz Дата изменения: Mon Jul 9 01:48:05 2007 Дата индексирования: Tue Oct 2 02:46:01 2012 Кодировка:

XMM-Newton Science Analysis System Page: 1
omcomb
July 8, 2007
Abstract
Combines 4 separate full-frame low resolution (engineering 2) mode image seg-
ments into a single image.
1 Instruments/Modes
Instrument Mode
OM IMAGING
2 Use
pipeline processing yes
interactive analysis yes
3 Description
The current version of omcomb combines the four image segments generated by the full-frame low reso-
lution mode into a single image, which the OM imaging chain task, OMICHAIN, can then process.
This task was originally written for use by the OM slew-chain task in the process of building a com-
plete OM at-eld: there it combined the 4 science windows from a single exposure, to produce 1/4
of a complete OM at-eld. Subsequently, a new, full-frame low-resolution OM science mode has been
introduced, (also known as Engineering-2 mode), in which a single exposure of the whole eld of view
is acquired at low resolution using BPE (electronic) binning. The resulting image, 1024x1024 pixels, is
telemetered as a sequence of four separate, but adjacent rectangular segments, each 256x1024 pixels in
size. A requirement therefore arose for a task in the OM imaging-chain to recombine the four full-frame
low-resolution mode image segments into a single image, and since at the present time the OM slew-chain
task is disabled, omcomb has been modied to perform this task. As and when slew processing is again
needed to produce at-elds, that functionality will be re-instigated in omcomb so that it can perform
either task.
xmmsas 20070708 1801-7.1.0

XMM-Newton Science Analysis System Page: 2
4 Parameters
This section documents the parameters recognized by this task (if any).
Parameter Mand Type Default Constraints
imagesets yes List
of le-
names
List of input image datasets to be combined
outset yes Filename
Name of output full-frame image dataset
5 Errors
This section documents warnings and errors generated by this task (if any). Note that warnings and
errors can also be generated in the SAS infrastructure libraries, in which case they would not be docu-
mented here. Refer to the index of all errors and warnings available in the HTML version of the SAS
documentation.
Invalid x-image size (fatal)
f ilename
Invalid y-image size (fatal)
f ilename
4 image les are required (fatal)
only N were provided
Invalid WINDOWXO value (x) for le name (fatal)
WINDOWX0 should be either 0, 512, 1024 or 1536
2 FILES (name and name) have identical WINDOWX0 values (fatal)
Invalid WINDOWYO value (x) for le name (fatal)
WINDOWY0 should be 0
Invalid WINDOWDX value (x) for le name (fatal)
WINDOWDX should be 512
Invalid WINDOWDY value (x) for le name (warning)
corrective action: WINDOWDY should be 2048
Invalid BINBPE value for le name (warning)
corrective action: BINBPE should be TRUE
xmmsas 20070708 1801-7.1.0

XMM-Newton Science Analysis System Page: 3
6 Input Files
1. List of image les (image in primary header)
7 Output Files
1. Output image le
8 Algorithm
Check that the number of files in the input image list is 4- if not abort with
an appropriate error message.
For each input image:
1) Check that BINBPE is set to TRUE.
2) Check that the WINDOWDX value is 512.
3) Check that the WINDOWX0 value is either 0, 512, 1024 OR 1536.
4) Check that this WINDOWX0 value is not identical to one of the previous values.
5) Check that the WINDOWY0 value is 0.
6) Check that the WINDOWDY value is 2048.
If any of the above checks fail, abort with an appropriate message.
Combine the 4 images into a single image.
Create the output file, write the image to the file and add the
appropriate keywords.
9 Comments
References
xmmsas 20070708 1801-7.1.0