; STFND ;--------------------------------------------------------------- ;! Task to find stars in an image and generate an ST table. ;# TASK PLOT OPTICAL ;----------------------------------------------------------------------- ;; Copyright (C) 1995, 2006, 2009 ;; Associated Universities, Inc. Washington DC, USA. ;; ;; This program is free software; you can redistribute it and/or ;; modify it under the terms of the GNU General Public License as ;; published by the Free Software Foundation; either version 2 of ;; the License, or (at your option) any later version. ;; ;; This program is distributed in the hope that it will be useful, ;; but WITHOUT ANY WARRANTY; without even the implied warranty of ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ;; GNU General Public License for more details. ;; ;; You should have received a copy of the GNU General Public ;; License along with this program; if not, write to the Free ;; Software Foundation, Inc., 675 Massachusetts Ave, Cambridge, ;; MA 02139, USA. ;; ;; Correspondence concerning AIPS should be addressed as follows: ;; Internet email: aipsmail@nrao.edu. ;; Postal address: AIPS Project Office ;; National Radio Astronomy Observatory ;; 520 Edgemont Road ;; Charlottesville, VA 22903-2475 USA ;----------------------------------------------------------------------- STFND LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC STFND: Task to find stars in an image and generate an ST table. INNAME Image name(name). INCLASS Image name(class). INSEQ 0.0 9999.0 Image name(seq. #). 0=>high INDISK Disk drive #. 0=>any OUTVERS 0.0 46655.0 STar file version number. BLC Bottem Left pixel of Region TRC Top Right pixel of Region CPARM 1: Threshold brightness 2: Max distance to merge 3,4: Min, Max Star Area 5,6: Star size scale 7: Star size constant (asec) 8: Star type to create 9: Maximum number of stars 10: >0 => Return star Ra, Dec ---------------------------------------------------------------- STFND Type: Task Use: STFND reads through an image and finds objects which are above a threshold value and cover a user specified number of pixels. Creates an ST table which can be used for plotting. (or viewed with PRTAB) Adverbs: INNAME......Image name (name). Standard defaults. INCLASS.....Image name (class). Standard defaults. INSEQ.......Image name (seq. #). 0 => highest. INDISK......Disk unit #. 0 => any. OUTVERS.....Version number of ST (star position) file to be created. 0 => highest+1. BLC.........Bottom right corner in input image of desired subimage. Default is entire image. TRC.........Top right corner in input image of desired subimage. Default is entire image. CPARM.......User specified array 1: Threshold brightness 2: Max distance to merge 3,4: Min, Max Star Area 5,6: Star size scale 7: Star size constant (asec) 8: Star type to create 9: Maximum number of stars 10: >-1 => Return star Ra, Dec See explain for details. ---------------------------------------------------------------- STFND: Task to find stars in an image and create an ST table. RELATED PROGRAMS: STARS, CNTR, PCNTR, GREYS, PRTAB PURPOSE STFND reads through an image and finds objects which are brighter than an input limit and cover a specified range of pixels. The star (ST) Table can optionally contain the RA DEC and angular size of the star or the pixel number and total number of counts cooresponding to the star. The ST table can be view with PRTAB and handled by all the standard table editting tasks. COMMENTS The AIPS adverb CPARM contains the various options for detecting stars. CPARM(1) The minimum brightness to be used for a star detection. (default is 95% of map peak) CPARM(2) Maximum distance to merge objects (1 = objects must be adjacent to be merged. 2 = objects will be merged if separated by 1 (low) pixel, etc CPARM(3) Minimum area (in pixels) a star must cover to be considered a detection. CPARM(4) Maximum area (in pixels) a star must cover to be considered a detection. Set this parameter to exclude galaxies and/or pairs of stars. CPARM(5-7)Star size scale. The star is symetric in RA+Dec, and the star size is a function of the square root of the area the star covers and the sum of all pixels composing the star. ie: Size = CPARM(5)*sqrt(area) + CPARM(6)*total_sum + CPARM(7) Note that CPARM(7) is in arc seconds. CPARM(8) Type of Star mark to put in the ST table. There are 24 different types of star marks. 1: Plus sign (default) 12: Five pointed star 2: Cross (X) 13: Star of David 3: Circle 14: Seven-pointed star 4: Box 15: Eight-pointed star 5: Triangle 16: Nine-pointed star 6: Diamond 17: Ten-pointed star 7: Pentagon 18: 11-pointed star 8: Hexagon 19: 12-pointed star 9: Septagon 20: 13-pointed star 10: Octagon 21: 14-pointed star 11: Nine-gon 22: Plus with gap 23: Vertical line 24: Cross (X) with gap CPARM(9) Maximum number of stars to create. (the default is 100) CPARM(10) Return the star pixel location if CPARM(10) <= -1.0, otherwise return the star RA and DEC The stars file assumes RA and Dec in the plotting routines. You can view the contents of the ST file with PRTAB. You can plot it on images with GREYS, CNTR, PCNTR, KNTR and others. ----------------------------------------------------------------