new_contents: #! /usr/bin/env python
  # -*- coding: utf-8 -*-
  # Adds my copyright notice to photos.
  #
  # Copyright © 2011 R.F. Smith <rsmith@xs4all.nl>. All rights reserved.
  # Time-stamp: <2011-11-06 20:19:28 rsmith>
  # 
  # Redistribution and use in source and binary forms, with or without
  # modification, are permitted provided that the following conditions
  # are met:
  # 1. Redistributions of source code must retain the above copyright
  #    notice, this list of conditions and the following disclaimer.
  # 2. Redistributions in binary form must reproduce the above copyright
  #    notice, this list of conditions and the following disclaimer in the
  #    documentation and/or other materials provided with the distribution.
  # 
  # THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  # ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  # ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
  # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  # OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  # HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  # LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  # OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  # SUCH DAMAGE.
  
  import sys
  import shlex, subprocess
  from multiprocessing import Pool, Lock
  from os import utime
  from time import mktime
  
  def processfile(name):
      args = shlex.split("exiftool -CreateDate {}".format(name))
      createdate = subprocess.check_output(args)
      fields = createdate.split(":")
      year = int(fields[1])
      cr = "R.F. Smith <rsmith@xs4all.nl> http://rsmith.home.xs4all.nl/"
      cmt = "Copyright © {} {}".format(year, cr)
      cmd = "exiftool -Copyright='{}' -Comment='{}' -overwrite_original -q {}"
      args = shlex.split(cmd.format(cr, cmt, name))
      rv = subprocess.call(args)
      modtime = int(mktime((year, int(fields[2]), int(fields[3][:2]), 
                        int(fields[3][3:]), int(fields[4]), int(fields[5]), 
                        0,0,-1)))
      utime(name, (modtime, modtime))
      globallock.acquire()
      if rv == 0:
          print "File '{}' processed.".format(name)
      else:
          print "Error when processing file '{}'".format(name)
      globallock.release()
  
  if __name__ == '__main__':
      files = sys.argv[1:]
      try:
          subprocess.check_output(['exiftool', '-ver'], stderr=subprocess.STDOUT)
      except CalledProcessError:
          print "Exiftool not found! exiting."
          exit(1)
      globallock = Lock()
      p = Pool()
      p.map(processfile, files)
  
subject: Replace markphotos with parallel version. written in Python.