include	<imhdr.h>
include	<imset.h>

$for (silrdx)

# FIXCOL -- Linearly interpolate columns across a region.

procedure fixcol$t (image, x1, x2, y1, y2)

pointer	image				# Image pointer
int	x1, x2, y1, y2			# Region to be fixed

int	i, j, nx, ny
real	f1, f2, scale
pointer	a, b, c
pointer	imgs2$t(), imps2$t()

begin
	c = imps2$t (image, x1, x2, y1, y2)

	nx = x2 - x1 + 1
	ny = y2 - y1 + 1
	if (x1 == 1) {
	    a = imgs2$t (image, x2 + 1, x2 + 1, y1, y2)
	    do i = 1, ny
		call amovk$t (Mem$t[a + i - 1], Mem$t[c + (i - 1) * nx], nx)
	} else if (x2 == IM_LEN (image, 1)) {
	    a = imgs2$t (image, x1 - 1, x1 - 1,  y1, y2)
	    do i = 1, ny
		call amovk$t (Mem$t[a + i - 1], Mem$t[c + (i - 1) * nx], nx)
	} else {
	    call imseti (image, IM_NBUFS, 2)
	    a = imgs2$t (image, x1 - 1, x1 - 1, y1, y2)
	    b = imgs2$t (image, x2 + 1, x2 + 1, y1, y2)
	    do i = 1, ny {
		f1 = Mem$t[a + i - 1]
		f2 = Mem$t[b + i - 1]
		scale = (f2 - f1) / (nx + 1)
		do j = 1, nx
		    Mem$t[c + (i - 1) * nx + j - 1] = j * scale + f1
	    }
	}
end

$endfor