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MIXUP-To mixup the position of all the pixels in an image    

Description:
Creates an equivalent noise image by swapping the positions of pairs of pixels taken from an image. This ensures that structure due to galaxies/stars etc is spread randomly throughout the image but the count value statistics are retained.

The routine may be used in conjunction with SKEW, SELFC, SELFCW or CORR when searching for low contrast objects. It provides comparison noise images which may be used to determine the significance of 'objects' identified by the other applications.

Usage:
MIXUP IN OUT

Parameters:
IN = _NDF (Read)
The name of the NDF that is to be scrambled.
OUT = _NDF (Write)
The name of the NDF data that will be created.

Examples:
mixup in=ic3374 out=ic3374m

The pixel positions in the input file IC3374 will be scrambled and the resulting image output as IC3374M.



next up previous
Next: SECTOR-May be used to display the average pixel values within a wedge shaped sector/slice of the image
Up: Description of the ESP routines
Previous: MASK-Uses an ARD file to set some pixels of a given image to bad

ESP --- Extended Surface Photometry
Starlink User Note 180
Norman Gray
Mark Taylor
Grant Privett
27 January 2000
E-mail:ussc@star.rl.ac.uk

Copyright © 2002 Council for the Central Laboratory of the Research Councils