1 files changed, 80 insertions, 0 deletions
diff --git a/editor/pamstretch-gen b/editor/pamstretch-gen
new file mode 100755
index 00000000..cd59a36b
--- /dev/null
+++ b/editor/pamstretch-gen
@@ -0,0 +1,80 @@
+#!/bin/sh
+#
+# pamstretch-gen - a shell script which acts a little like a general
+# form of pamstretch, by scaling up with pamstretch then scaling
+# down with pamscale.
+#
+# it also copes with N<1, but then it just uses pamscale. :-)
+#
+# Formerly named 'pnminterp-gen' and 'pnmstretch-gen'.
+#
+# Copyright (C) 1998,2000 Russell Marks.
+# 
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or (at
+# your option) any later version.
+# 
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+# 
+
+
+if [ "$1" = "" ]; then
+  echo 'usage: pamstretch-gen N [pnmfile]'
+  exit 1
+fi
+
+tempdir="${TMPDIR-/tmp}/pamstretch-gen.$$"
+mkdir $tempdir || { echo "Could not create temporary file. Exiting."; exit 1;}
+chmod 700 $tempdir
+tempfile=$tempdir/pnmig
+
+trap 'rm -rf $tempdir' 0 1 3 15
+
+if ! cat $2 >$tempfile 2>/dev/null; then
+  echo 'pamstretch-gen: error reading file' 1>&2
+  exit 1
+fi
+
+if ! pnmfile $tempfile 1>/dev/null 2>/dev/null; then
+  echo 'Not valid pnm input'
+  exit 1
+fi
+
+# we use the width as indication of how much to scale; width and
+# height are being scaled equally, so this should be ok.
+width=`pnmfile $tempfile 2>/dev/null|cut -d " " -f 3`
+
+if [ "$width" = "" ]; then
+  echo 'pamstretch-gen: not a PNM file' 1>&2
+  exit 1
+fi
+
+# should really use dc for maths, but awk is less painful :-)
+target_width=`awk 'BEGIN{printf("%d",'0.5+"$width"*"$1"')}'`
+
+# work out how far we have to scale it up with pamstretch so that the
+# new width is >= the target width.
+int_scale=`awk '
+BEGIN {
+int_scale=1;int_width='"$width"'
+while(int_width<'"$target_width"')
+  {
+  int_scale++
+  int_width+='"$width"'
+  }
+print int_scale
+}'`
+
+if [ "$int_scale" -eq 1 ]; then
+  pamscale "$1" $tempfile
+else
+  pamstretch "$int_scale" $tempfile | pnmscale -xsi "$target_width"
+fi