PREPROCESS
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Last Updated Jan 2001
Copyright © 2001 The Association of Universities for Research in Astronomy, Inc. All Rights Reserved.
Purpose :
This routine checks for essential files and computes some simple image statistics.Procedure :
Some basic parameters are read from the header and copied to the DID file for convenience. The following statistics are computed for a section of the image.- Image Entropy
- Mean and rms (with sigma clipping)
- Pixel-Pixel differences
- 10,20,30,40,50,60,70,80,90% percentiles
Calling Sequence :
- PREPROCESS imagefile
- [/XPOS=cx] X position for image statistics {def=8193}
- [/YPOS=cy] Y position for image statistics {def=8193}
- [/XSIZE=nx] X size for image statistics {def=512}
- [/YSIZE=ny] Y size for image statistics {def=512}
- [/K_VALUE=k] k sigma clipping value {def=2.5}
- [/TOLERANCE=t] convergence tolerance for clipping {def=25}
- [/MAX_ITER=i] max.iterations of clipping {def=10}
- [/COMMENT="string"] comment to write to DID file
- [/[no]ANNOTATE] write data to DID file
- [/NEW] Create new DID file for data
- [/DEBUG]
- [/YPOS=cy] Y position for image statistics {def=8193}
Availability :
- GSSS AXP - yes
- GSSS VAX - yes
- PIXELS - no