Added reverse version.

1 files changed, 109 insertions, 0 deletions

diff --git a/pdf-zip-rev.sh b/pdf-zip-rev.sh
new file mode 100755
index 000000000000..875460b6dc4b
--- /dev/null
+++ b/pdf-zip-rev.sh
@@ -0,0 +1,109 @@
+#!/bin/bash
+
+### Author: Anonymous.
+
+extendedhelp="### $0
+# 
+# As 'pdf-zip', but the second input file will be reversed, thus
+# enabling to directly combine two PDFs back into one document which
+# were created by scanning several pieces of paper on front and back
+# side with a non-duplex automatic document feeding scanner.
+# 
+# Takes two input PDF files, and writes an output PDF file.
+# Thereby using the pages from the first input file as the odd pages
+# of the output file and the pages of the second input file as the
+# even pages of the output file IN REVERSED ORDER.
+# 
+# In more detail, if o ('odd') is a page number of the first input
+# file, e ('even') is a page number of the second input file and
+# r ('result') is a page number of the output file, the following
+# relations should hold true:
+# 
+#   2*(E-e+1) --> r (for     r/2 a natural number)
+#   2*o - 1   --> r (for (r+1)/2 a natural number),
+# 
+# where E is the total number of pages in the second input file.
+# 
+# In case one input file is too short to fill up, the above relations
+# will _not_ hold true after one input file ran out of pages; instead,
+# the output file will just be filled up with the remaining pages of
+# the longer input file.
+# 
+# Internally, 'pdftk' does the work, and this is just a script
+# wrapping around 'pdftk'.
+# 
+###"
+
+output_file_default='/dev/stdout'
+
+errmsg() {
+  if [ "$#" -ge "1" ]; then
+    msg="$1"
+  else
+    msg="$0: Unspecified error."
+  fi
+  
+  echo "${msg}" >> /dev/stderr
+}
+
+exiterror() {
+  if [ "$#" -ge "1" ]; then
+    msg="$1"
+  else
+    msg="$0: Unspecified error."
+  fi
+  
+  if [ "$#" -ge "2" ]; then
+    exitcode="$2"
+  else
+    exitcode=2
+  fi
+  
+  errmsg "${msg}"
+  exit "${exitcode}"
+}
+
+printusage() {
+  echo "Usage:"
+  echo "  $0 <odd_pages_pdf_input_file> <even_pages_pdf_input_file> [<pdf_output_file> [<additional_pdftk_options>]]"
+  echo "(<pdf_output_file> defaults to '${output_file_default}')"
+  echo "For example, specify 'verbose' as an additional pdftk-option to get verbose output."
+}
+
+printextendedhelp() {
+  echo "${extendedhelp}"
+}
+
+if [ "$#" -lt "2" ]; then
+  errmsg "$0: Error: Too few arguments specified."
+  errmsg ""
+  errmsg "$(printusage)"
+  errmsg ""
+  errmsg "=== Extended information on this software: ==="
+  errmsg ""
+  errmsg "$(printextendedhelp)"
+  errmsg ""
+  exiterror "$0: Aborting, since too few arguments specified." 1
+fi
+
+oddinput_file="$1"
+eveninput_file="$2"
+
+shift
+shift
+
+if [ "$#" -ge "1" ]; then
+  output_file="$1"
+  shift
+else
+  output_file="${output_file_default}"
+fi
+
+pdftk A="${oddinput_file}" B="${eveninput_file}" shuffle A Bend-1 output "${output_file}" "$@"
+exitcode_pdftk="$?"
+
+if [ "${exitcode_pdftk}" -ne 0 ]; then
+  errmsg "$0: Error: The run of 'pdftk' produced an error. See above error message from the call to 'pdftk' for details."
+fi
+exit "${exitcode_pdftk}"
+