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include <mach.h>
include "../lib/apphotdef.h"
include "../lib/apphot.h"
include "../lib/noisedef.h"
include "../lib/centerdef.h"
include "../lib/center.h"
define CONVERT .424660900 # conversion from fwhmpsf to sigma
# APFITCENTER -- Procedure to fit the centers using either 1) the intensity
# weighted mean of the marginal distributions, 2) a Gaussian fit to the
# marginals assuming a fixed sigma or 3) a simplified version of the optimal
# filtering method using a Gaussian of fixed sigma to model the profile.
int procedure apfitcenter (ap, im, wx, wy)
pointer ap # pointer to the apphot structure
pointer im # pointer to the IRAF image
real wx, wy # object coordinates
int i, niter, ier, fier, lowsnr
pointer ctr, nse
real cthreshold, datamin, datamax, owx, owy, xshift, yshift, med
int apctrbuf(), ap_ctr1d(), ap_mctr1d(), ap_gctr1d(), ap_lgctr1d()
real ap_csnratio(), amedr()
begin
ctr = AP_PCENTER(ap)
nse = AP_NOISE(ap)
ier = AP_OK
# Initialize.
AP_CXCUR(ctr) = wx
AP_CYCUR(ctr) = wy
AP_OXINIT(ctr) = INDEFR
AP_OYINIT(ctr) = INDEFR
AP_XCENTER(ctr) = INDEFR
AP_YCENTER(ctr) = INDEFR
AP_OXCENTER(ctr) = INDEFR
AP_OYCENTER(ctr) = INDEFR
AP_XSHIFT(ctr) = 0.0
AP_YSHIFT(ctr) = 0.0
AP_OXSHIFT(ctr) = 0.0
AP_OYSHIFT(ctr) = 0.0
AP_XERR(ctr) = INDEFR
AP_YERR(ctr) = INDEFR
# Return input coordinates if centering is disabled.
if (IS_INDEFR(wx) || IS_INDEFR(wy)) {
return (AP_CTR_NOAREA)
} else if (AP_CENTERFUNCTION(ctr) == AP_NONE) {
AP_XCENTER(ctr) = wx
AP_YCENTER(ctr) = wy
switch (AP_WCSOUT(ap)) {
case WCS_WORLD, WCS_PHYSICAL:
call ap_ltoo (ap, wx, wy, AP_OXINIT(ctr), AP_OYINIT(ctr), 1)
call ap_ltoo (ap, wx, wy, AP_OXCENTER(ctr), AP_OYCENTER(ctr), 1)
case WCS_TV:
call ap_ltov (im, wx, wy, AP_OXINIT(ctr), AP_OYINIT(ctr), 1)
call ap_ltov (im, wx, wy, AP_OXCENTER(ctr), AP_OYCENTER(ctr), 1)
default:
AP_OXINIT(ctr) = wx
AP_OYINIT(ctr) = wy
AP_OXCENTER(ctr) = wx
AP_OYCENTER(ctr) = wy
}
return (AP_OK)
}
# Intialize.
owx = wx
owy = wy
niter = 0
if (IS_INDEFR(AP_SKYSIGMA(nse)) || IS_INDEFR(AP_CTHRESHOLD(ctr)) ||
AP_CTHRESHOLD(ctr) <= 0.0)
cthreshold = 0.0
else
cthreshold = AP_CTHRESHOLD(ctr) * AP_SKYSIGMA(nse)
repeat {
# Set initial cursor position.
AP_CXCUR(ctr) = owx
AP_CYCUR(ctr) = owy
# Get centering pixels.
ier = apctrbuf (ap, im, owx, owy)
if (ier == AP_CTR_NOAREA) {
AP_XCENTER(ctr) = wx
AP_YCENTER(ctr) = wy
AP_XSHIFT(ctr) = 0.0
AP_YSHIFT(ctr) = 0.0
AP_XERR(ctr) = INDEFR
AP_YERR(ctr) = INDEFR
switch (AP_WCSOUT(ap)) {
case WCS_WORLD, WCS_PHYSICAL:
call ap_ltoo (ap, wx, wy, AP_OXINIT(ctr), AP_OYINIT(ctr), 1)
call ap_ltoo (ap, wx, wy, AP_OXCENTER(ctr),
AP_OYCENTER(ctr), 1)
case WCS_TV:
call ap_ltov (im, wx, wy, AP_OXINIT(ctr), AP_OYINIT(ctr), 1)
call ap_ltov (im, wx, wy, AP_OXCENTER(ctr),
AP_OYCENTER(ctr), 1)
default:
AP_OXINIT(ctr) = wx
AP_OYINIT(ctr) = wy
AP_OXCENTER(ctr) = wx
AP_OYCENTER(ctr) = wy
}
AP_OXSHIFT(ctr) = 0.0
AP_OYSHIFT(ctr) = 0.0
return (ier)
}
# Clean the subraster.
if (AP_CLEAN(ctr) == YES)
call apclean (ap, Memr[AP_CTRPIX(ctr)], AP_CNX(ctr),
AP_CNY(ctr), AP_CXC(ctr), AP_CYC(ctr))
# Compute the datalimits.
if (cthreshold <= 0.0)
call alimr (Memr[AP_CTRPIX(ctr)], AP_CNX(ctr) * AP_CNY(ctr),
datamin, datamax)
else {
datamin = MAX_REAL
datamax = -MAX_REAL
do i = 1, AP_CNY(ctr) {
med = amedr (Memr[AP_CTRPIX(ctr)+(i-1)*AP_CNX(ctr)],
AP_CNX(ctr))
if (med < datamin)
datamin = med
if (med > datamax)
datamax = med
}
}
# Apply threshold and check for positive or negative features.
if (AP_POSITIVE(ap) == YES) {
call apsetr (ap, CDATALIMIT, datamin)
call asubkr (Memr[AP_CTRPIX(ctr)], datamin +
cthreshold, Memr[AP_CTRPIX(ctr)], AP_CNX(ctr) *
AP_CNY(ctr))
call amaxkr (Memr[AP_CTRPIX(ctr)], 0.0, Memr[AP_CTRPIX(ctr)],
AP_CNX(ctr) * AP_CNY(ctr))
} else {
call apsetr (ap, CDATALIMIT, datamax)
call anegr (Memr[AP_CTRPIX(ctr)], Memr[AP_CTRPIX(ctr)],
AP_CNX(ctr) * AP_CNY(ctr))
call aaddkr (Memr[AP_CTRPIX(ctr)], datamax -
cthreshold, Memr[AP_CTRPIX(ctr)], AP_CNX(ctr) *
AP_CNY(ctr))
call amaxkr (Memr[AP_CTRPIX(ctr)], 0.0,
Memr[AP_CTRPIX(ctr)], AP_CNX(ctr) * AP_CNY(ctr))
}
# Test signal to noise ratio.
if (ap_csnratio (ap, Memr[AP_CTRPIX(ctr)], AP_CNX(ctr),
AP_CNY(ctr), 0.0) < AP_MINSNRATIO(ctr))
lowsnr = YES
else
lowsnr = NO
# Compute the x and y centers.
switch (AP_CENTERFUNCTION(ctr)) {
case AP_CENTROID1D:
if (AP_CTHRESHOLD(ctr) <= 0.0) {
fier = ap_mctr1d (Memr[AP_CTRPIX(ctr)], AP_CNX(ctr),
AP_CNY(ctr), AP_EPADU(nse), AP_XCENTER(ctr),
AP_YCENTER(ctr), AP_XERR(ctr), AP_YERR(ctr))
if (IS_INDEFR (AP_XERR(ctr)))
AP_XCENTER(ctr) = AP_CXC(ctr)
if (IS_INDEFR (AP_YERR(ctr)))
AP_YCENTER(ctr) = AP_CYC(ctr)
} else {
fier = ap_ctr1d (Memr[AP_CTRPIX(ctr)], AP_CNX(ctr),
AP_CNY(ctr), AP_EPADU(nse), AP_XCENTER(ctr),
AP_YCENTER(ctr), AP_XERR(ctr), AP_YERR(ctr))
if (IS_INDEFR (AP_XERR(ctr)))
AP_XCENTER(ctr) = AP_CXC(ctr)
if (IS_INDEFR (AP_YERR(ctr)))
AP_YCENTER(ctr) = AP_CYC(ctr)
}
case AP_GAUSS1D:
fier = ap_gctr1d (Memr[AP_CTRPIX(ctr)], AP_CNX(ctr),
AP_CNY(ctr), CONVERT * AP_FWHMPSF(ap) * AP_SCALE(ap),
AP_CMAXITER(ctr), AP_XCENTER(ctr), AP_YCENTER(ctr),
AP_XERR(ctr), AP_YERR(ctr))
case AP_OFILT1D:
fier = ap_lgctr1d (Memr[AP_CTRPIX(ctr)], AP_CNX(ctr),
AP_CNY(ctr), AP_CXC(ctr), AP_CYC(ctr), CONVERT *
AP_FWHMPSF(ap) * AP_SCALE(ap), AP_CMAXITER(ctr),
AP_EPADU(nse), AP_SKYSIGMA(nse), AP_XCENTER(ctr),
AP_YCENTER(ctr), AP_XERR(ctr), AP_YERR(ctr))
default:
# do nothing gracefully
}
# Confine the next x center to the data box.
AP_XCENTER(ctr) = max (0.5, min (AP_CNX(ctr) + 0.5,
AP_XCENTER(ctr)))
xshift = AP_XCENTER(ctr) - AP_CXC(ctr)
AP_XCENTER(ctr) = xshift + owx
AP_XSHIFT(ctr) = AP_XCENTER(ctr) - wx
# Confine the next y center to the data box.
AP_YCENTER(ctr) = max (0.5, min (AP_CNY(ctr) + 0.5,
AP_YCENTER(ctr)))
yshift = AP_YCENTER(ctr) - AP_CYC(ctr)
AP_YCENTER(ctr) = yshift + owy
AP_YSHIFT(ctr) = AP_YCENTER(ctr) - wy
switch (AP_WCSOUT(ap)) {
case WCS_PHYSICAL, WCS_WORLD:
call ap_ltoo (ap, AP_XCENTER(ctr), AP_YCENTER(ctr),
AP_OXCENTER(ctr), AP_OYCENTER(ctr), 1)
call ap_ltoo (ap, AP_XCENTER(ctr) - AP_XSHIFT(ctr),
AP_YCENTER(ctr) - AP_YSHIFT(ctr), AP_OXINIT(ctr),
AP_OYINIT(ctr), 1)
AP_OXSHIFT(ctr) = AP_OXCENTER(ctr) - AP_OXINIT(ctr)
AP_OYSHIFT(ctr) = AP_OYCENTER(ctr) - AP_OYINIT(ctr)
case WCS_TV:
call ap_ltov (im, AP_XCENTER(ctr), AP_YCENTER(ctr),
AP_OXCENTER(ctr), AP_OYCENTER(ctr), 1)
call ap_ltov (im, AP_XCENTER(ctr) - AP_XSHIFT(ctr),
AP_YCENTER(ctr) - AP_YSHIFT(ctr), AP_OXINIT(ctr),
AP_OYINIT(ctr), 1)
AP_OXSHIFT(ctr) = AP_OXCENTER(ctr) - AP_OXINIT(ctr)
AP_OYSHIFT(ctr) = AP_OYCENTER(ctr) - AP_OYINIT(ctr)
default:
AP_OXINIT(ctr) = AP_XCENTER(ctr) - AP_XSHIFT(ctr)
AP_OYINIT(ctr) = AP_YCENTER(ctr) - AP_YSHIFT(ctr)
AP_OXCENTER(ctr) = AP_XCENTER(ctr)
AP_OYCENTER(ctr) = AP_YCENTER(ctr)
AP_OXSHIFT(ctr) = AP_XSHIFT(ctr)
AP_OYSHIFT(ctr) = AP_YSHIFT(ctr)
}
# Setup for next iteration.
niter = niter + 1
owx = AP_XCENTER(ctr)
owy = AP_YCENTER(ctr)
} until ((fier != AP_OK && fier != AP_CTR_NOCONVERGE) ||
(niter >= AP_CMAXITER(ctr)) || (abs (xshift) < 1.0 &&
abs (yshift) < 1.0))
# Return appropriate error code.
if (fier != AP_OK) {
AP_XCENTER(ctr) = wx
AP_YCENTER(ctr) = wy
AP_XSHIFT(ctr) = 0.0
AP_YSHIFT(ctr) = 0.0
AP_XERR(ctr) = INDEFR
AP_YERR(ctr) = INDEFR
switch (AP_WCSOUT(ap)) {
case WCS_WORLD, WCS_PHYSICAL:
call ap_ltoo (ap, wx, wy, AP_OXINIT(ctr), AP_OYINIT(ctr), 1)
call ap_ltoo (ap, wx, wy, AP_OXCENTER(ctr), AP_OYCENTER(ctr), 1)
case WCS_TV:
call ap_ltov (im, wx, wy, AP_OXINIT(ctr), AP_OYINIT(ctr), 1)
call ap_ltov (im, wx, wy, AP_OXCENTER(ctr), AP_OYCENTER(ctr), 1)
default:
AP_OXINIT(ctr) = wx
AP_OYINIT(ctr) = wy
AP_OXCENTER(ctr) = wx
AP_OYCENTER(ctr) = wy
}
AP_OXSHIFT(ctr) = 0.0
AP_OYSHIFT(ctr) = 0.0
return (fier)
} else if (ier == AP_CTR_BADDATA) {
return (AP_CTR_BADDATA)
} else if (lowsnr == YES) {
return (AP_CTR_LOWSNRATIO)
} else if (abs (AP_XSHIFT(ctr)) > (AP_MAXSHIFT(ctr) * AP_SCALE(ap))) {
return (AP_CTR_BADSHIFT)
} else if (abs (AP_YSHIFT(ctr)) > (AP_MAXSHIFT(ctr) * AP_SCALE(ap))) {
return (AP_CTR_BADSHIFT)
} else if (ier == AP_CTR_OUTOFBOUNDS) {
return (AP_CTR_OUTOFBOUNDS)
} else {
return (AP_OK)
}
end
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