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# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
include <syserr.h>
include <imhdr.h>
include <imio.h>
# IMGL2? -- Get a line from an apparently two 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 imgl2i (im, linenum)
pointer im # image header pointer
int linenum # line to be read
int fd, nchars
long vs[2], ve[2], offset
pointer bp, imggsi(), freadp()
errchk imopsf, imerr
begin
repeat {
if (IM_FAST(im) == YES && IM_PIXTYPE(im) == TY_INT) {
fd = IM_PFD(im)
if (fd == NULL) {
call imopsf (im)
next
}
if (linenum < 1 || linenum > IM_LEN(im,2))
call imerr (IM_NAME(im), SYS_IMREFOOB)
offset = (linenum - 1) * IM_PHYSLEN(im,1) * SZ_INT +
IM_PIXOFF(im)
nchars = IM_PHYSLEN(im,1) * SZ_INT
ifnoerr (bp = (freadp (fd, offset, nchars) - 1) / SZ_INT + 1)
return (bp)
}
vs[1] = 1
ve[1] = IM_LEN(im,1)
vs[2] = linenum
ve[2] = linenum
return (imggsi (im, vs, ve, 2))
}
end
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