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# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
include <syserr.h>
include <imhdr.h>
include <imio.h>
# IMGL3? -- Get a line from an apparently three dimensional image. If there
# is only one input buffer, no image section, we are not referencing out of
# bounds, and no datatype conversion needs to be performed, directly access
# the pixels to reduce the overhead per line.
pointer procedure imgl3$t (im, line, band)
pointer im # image header pointer
int line # line number within band
int band # band number
int fd, nchars
long vs[3], ve[3], offset
pointer bp, imggs$t(), freadp()
errchk imopsf, imerr
begin
repeat {
if (IM_FAST(im) == YES && IM_PIXTYPE(im) == TY_PIXEL) {
fd = IM_PFD(im)
if (fd == NULL) {
call imopsf (im)
next
}
if (line < 1 || line > IM_LEN(im,2) ||
band < 1 || band > IM_LEN(im,3))
call imerr (IM_NAME(im), SYS_IMREFOOB)
offset = (((band - 1) * IM_PHYSLEN(im,2) + line - 1) *
IM_PHYSLEN(im,1)) * SZ_PIXEL + IM_PIXOFF(im)
nchars = IM_PHYSLEN(im,1) * SZ_PIXEL
ifnoerr (bp = (freadp (fd, offset, nchars) - 1) / SZ_PIXEL + 1)
return (bp)
}
vs[1] = 1
ve[1] = IM_LEN(im,1)
vs[2] = line
ve[2] = line
vs[3] = band
ve[3] = band
return (imggs$t (im, vs, ve, 3))
}
end
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