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SEGMENT(1)			 User Commands			    SEGMENT(1)

       Segment - segmentation based on signal structure

       astsegment [OPTION...] ASTRdata

       Segment	is part	of GNU Astronomy Utilities 0.13.  Segment will segment
       an initially labeled region based on structure with the signal. It will
       first  find true	clumps (local maxima), estimate	which ones have	strong
       connections, and	then grow them to cover	the full area of  each	detec-

       For more	information, please run	any of the following commands. In par-
       ticular the second contains a very comprehensive	 explanation  of  Seg-
       ment's invocation: expected input(s), output(s),	and a full description
       of all the options.

       All options and their values:
	      $	astsegment -P

       Inputs/Outputs and options:
	      $	info astsegment

       Full section in manual/book:
	      $	info Segment

       Full Gnuastro manual/book:
	      $	info gnuastro

       If you couldn't find your answer	in the manual, you can get direct help
       from  experienced  Gnuastro users and developers. For more information,
       please run:

	      $	info help-gnuastro

       Segment options:


	      HDU/extension of convolved image in file.

	      Convolved	image file to avoid convolution.

       -d, --detection=STR
	      Filename of detection image (to segment).

	      HDU containing detection image.

       -h, --hdu=STR/INT
	      HDU containing values (science image).

       -k, --kernel=STR
	      Filename of kernel to convolve with input.

	      HDU containing kernel image.

	      Filename of Sky values image to subtract.

	      HDU containing Sky value to subtract.

	      Filename of Sky standard deviation.

	      HDU containing Sky standard deviation.

	      STD input	is actually variance.

	      Tessellation (tile grid):

	      Tile IDs in an image, the	size of	input.

       -F, --remainderfrac=FLT
	      Fraction of remainder to split last tile.

	      Interpolation metric (radial, manhattan).

	      No. of neighbors to use for interpolation.

	      Only interpolate over the	blank tiles.

       -L, --largetilesize=INT[,INT]
	      Sim. to --tilesize, but for larger tiles.

       -M, --numchannels=INT[,..] No. of channels in dim.s (FITS order).

	      Display 1	element/tile, not full input res.

	      Work (not	tile) over channel edges.

       -Z, --tilesize=INT[,INT]
	      Regular tile size	on dim.s (FITS order).


       -D, --dontdelete
	      Don't delete output if it	exists.

       -K, --keepinputdir
	      Keep input directory for automatic output.

	      Finish after finding true	clumps.

       -o, --output=STR
	      Output file name.

	      Output only object and clump labels.

	      'txt', 'fits-ascii', 'fits-binary'.


       -B, --minskyfrac=FLT
	      Min. fraction of undetected area in tile.

	      Store segmentation steps in a file.

	      Save clump S/N values into a file.

       -c, --snquant=FLT
	      S/N Quantile of true sky clumps.

	      Save grown clumps	instead	of original.

       -G, --gthresh=FLT
	      Multiple of STD to stop growing clumps.

	      Built internal clumps from minima.

       -m, --snminarea=INT
	      Minimum area of clumps for S/N estimation.

	      Minimum number for S/N estimation.

       -O, --objbordersn=FLT
	      Min. S/N for grown clumps	as one object.

       -s, --clumpsnthresh=FLT
	      S/N threshold of true clumps.

       -v, --keepmaxnearriver
	      Keep clumps with peak touching a river.

       -y, --minriverlength=INT
	      Minimum len of useful grown clump	rivers.

	      Operating	modes:

       -?, --help
	      give this	help list

	      List all config files and	variables read.

       --cite BibTeX citation for this program.

	      Read configuration file STR immediately.

       -C, --continueaftercheck
	      Continue processing after	checks.

	      Do not parse any more configuration files.

	      Minimum bytes in array to	not use	ram RAM.

       -N, --numthreads=INT
	      Number of	CPU threads to use.

	      Only run if the program version is STR.

       -P, --printparams
	      Print parameter values to	be used	and abort.

       -q, --quiet
	      Only report errors, remain quiet about steps.

	      Don't print mmap'd file's	name and size.

       -S, --setdirconf
	      Set default values for this directory and	abort.

	      give a short usage message

       -U, --setusrconf
	      Set default values for this user and abort.

       -V, --version
	      print program version

       Mandatory or optional arguments to long options are also	 mandatory  or
       optional	for any	corresponding short options.

       GNU  Astronomy  Utilities home page:

       Report bugs to

       Copyright  (C)  2015-2020,  Free	 Software  Foundation,	Inc.   License
       GPLv3+: GNU General public license version 3 or later.
       This  is	 free  software:  you  are free	to change and redistribute it.
       There is	NO WARRANTY, to	the extent permitted by	law.

       Written/developed by Mohammad Akhlaghi

       The full	documentation for Segment is maintained	as a  Texinfo  manual.
       If  the	info and Segment programs are properly installed at your site,
       the command

	      info Segment

       should give you access to the complete manual.

GNU Astronomy Utilities	0.13	September 2020			    SEGMENT(1)


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