maskdereg: Deregister master object mask to individual object masks

Package: xdimsum

Usage

maskdereg omask sections outlist

Parameters

omask

The input object mask for the combined image. Omask is usually created by the mkmask task for the combined image created by the xnregistar task. The input object mask is assumed to consist entirely of 1's and 0's with object regions set to 1.

sections

The input sections or corners file usually written by the xnregistar task. Sections contains the name of the original input images, the x and y coordinates of the lower left corner of the input image in the combined image, and the x and y coordinates of the upper right corner of the input image in the combined image, in columns 1 through 5 respectively.

outlist

The list of output image masks or the string appended to the input image names in sections to create the output individual mask names.

y2n_angle = 0.0

The angle in degrees from the image y axis to the north axis measured from north through east. Y2n_angle is used to reorient the input object mask before creating the individual output object masks.

rotation = yes

Is the rotation of the input image north axis to the east axis counter-clockwise ? Y2n_angle is used to reorient the input object mask before creating the individual output object masks.

mkcrmask = no

Create object masks for comparison with the cosmic ray masks or for use with the second pass sky subtraction task xslm ?

update = yes

Write the names of the output object masks to the headers of the input images. If mkcrmask is "no" the object mask name keyword is "OBJMASK", if mkcrmask is "yes" it is "CROBJMAS".

Description

MASKDEREG creates individual object masks for the original input images using the object mask omask for the combined image written by the MKMASK task and the sections file sections written by the XNREGISTAR task.

The sections file contains the name of the original input image, the x and y coordinates of the lower left corner of the input image in the combined image, and the x and y coordinates of the upper right corner of the input image in the combined image, in columns 1 through 5.

The output object masks are assigned names of the form input image name // outlist if outlist begins with a ".", e.g. "demo01.msk.pl" if outlist = ".msk", and the original image name is "demo01.fits". All object masks are assumed to consist entirely of 0's and 1's with the object regions assigned values of 1.

By default XNREGISTAR orients the combined image to within 45 degrees of north pointing up and east pointing left. Therefore the input object mask created by MKMASK will normally have this orientation is well. The parameters y2n_angle and rotation are used to reorient the input object mask so that the orientation of the individual output object masks matches the orientation of the original images.

If update is "yes" then the name of output object mask is written into the header of the original input image. If mkcrmask is "no" the object mask keyword is "OBJMASK", otherwise it is "CROBJMAS".

Examples

1. Create individual object masks from a combined image mask.

cl> maskdereg mosaic.msk mosaic.corners ".obm" y2n_angle=0.0 \
    rotation+ mkcrmask- update+

Time requirements

Bugs

See also

xnregistar,mkmask,orient