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# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
include <imhdr.h>
include "imfort.h"
# IMGL3R -- Get a line from an image of type short or real. Automatic
# datatype conversion from short to real is performed if necessary.
# It is illegal to reference out of bounds.
procedure imgl3r (im, buf, lineno, bandno, ier)
pointer im # image descriptor
real buf[ARB] # user data buffer
int lineno # line number
int bandno # band number
int ier
long offset
int nchars, npix
int bfread()
begin
# Verify in bounds.
if (lineno < 1 || lineno > IM_LEN(im,2)) {
ier = IE_YOOB
call im_seterrim (ier, im)
return
} else if (bandno < 1 || bandno > IM_LEN(im,3)) {
ier = IE_ZOOB
call im_seterrim (ier, im)
return
}
npix = IM_LEN(im,1)
nchars = npix * IM_SZPIXEL(im)
# Compute offset into pixel file.
offset = IM_PIXOFF(im) +
((bandno-1) * IM_LEN(im,2) + (lineno-1)) * IM_LINESIZE(im)
# Read one line of data.
if (nchars != bfread (IM_PIXFP(im), buf, nchars, offset)) {
ier = IE_RDPIX
call im_seterrim (ier, im)
return
}
# Swap bytes if necessary.
call imswap (im, buf, nchars)
# Convert the datatype if necessary.
if (IM_PIXTYPE(im) == TY_SHORT)
call achtsr (buf, buf, npix)
ier = OK
end
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