#!/bin/csh -f

# RCSid $Id: pbilat.csh,v 1.3 2008/11/10 19:08:19 greg Exp $

#

# Bilateral Filter (fixed parameters for now)

#

set bfrac=0.02

set sigma=0.4

set vmin=1e-7

if ( $#argv != 1 ) then

	goto userr

endif

set inp="$1"

set rad=`getinfo -d < $inp:q | rcalc -i '-Y ${yr} +X ${xr}' -e '$1=sqrt(xr*yr)*'$bfrac`

set extrem=`pextrem -o $inp:q | rcalc -e "vmin:$vmin" -e 'max(a,b):if(a-b,a,b);$1=max($3*.265+$4*.670+$5*.065,vmin)'`

set nseg=`ev "ceil(log10($extrem[2]/$extrem[1])/$sigma)"`

if ( $nseg > 20 ) set nseg=20

onintr done

set tdir=`mktemp -d /tmp/blf.XXXXXX`

set gfunc="sq(x):x*x;gfunc(x):if(sq(x)-sq($sigma),0,sq(1-sq(x/$sigma)))"

set i=0

set imglist=()

while ( $i <= $nseg )

	set intens=`ev "$extrem[1]*($extrem[2]/$extrem[1])^($i/$nseg)"`

	pcomb -e $gfunc:q -e "vmin:$vmin" \

			-e 'max(a,b):if(a-b,a,b);l1=max(li(1),vmin)' \

			-e "lo=gfunc(log10(l1)-log10($intens))" \

			-o $inp > $tdir/gimg.hdr

	pcomb -e 'sf=gi(2);ro=sf*ri(1);go=sf*gi(1);bo=sf*bi(1)' \

			-o $inp $tdir/gimg.hdr > $tdir/g_p.hdr

	pgblur -r $rad $tdir/g_p.hdr \

		| pcomb -e 'sf=if(gi(2)-1e-6,1/gi(2),1e6)' \

			-e 'ro=sf*ri(1);go=sf*gi(1);bo=sf*bi(1)' \

			- "\!pgblur -r $rad $tdir/gimg.hdr" \

		> $tdir/gimg$i.hdr

	set imglist=($imglist $tdir/gimg$i.hdr)

	@ i++

end

cat > $tdir/interp.cal << _EOF_

{ Segmented intensity image interpolation }

max(a,b) : if(a-b, a, b);

NSEG : $nseg;

l1 = max(li(1), $vmin);

val = NSEG / log($extrem[2]/$extrem[1]) * (log(l1) - log($extrem[1]));

iv = floor(val);

ival = if(iv - (NSEG-1), NSEG-1, max(iv, 0));

xval = val - ival;

ro = (1-xval)*ri(ival+2) + xval*ri(ival+3);

go = (1-xval)*gi(ival+2) + xval*gi(ival+3);

bo = (1-xval)*bi(ival+2) + xval*bi(ival+3);

_EOF_

pcomb -h -f $tdir/interp.cal -o $inp:q $imglist

done:

rm -rf $tdir

exit 0

userr:

echo Usage: $0 input.hdr