extract flash swf from powerpoint pps python script

# this is a conversion of http://blog.interrupt3h.com/?p=250

import mmap, os
from argparse import ArgumentParser

MARKER=b'FWS'
EXT='bin'
FLASHEXT='swf'

def vprint(*arg, **args):
    if options.verbose:
        print(*arg, **args)

def newfilename(fn):
    base, ext = os.path.splitext(fn)
    return base+'.'+FLASHEXT

def process(fn):
    with open(fn, 'rb', 0) as f, \
        mmap.mmap(f.fileno(), 0, access=mmap.ACCESS_READ) as s:
        i = s.find(MARKER)
        if i == -1:
            print('unable to find marker')
            return
        nfn = newfilename(fn)
        with open(nfn, 'wb') as nf:
            nf.write(s[i:])
        print('wrote flash to', nfn)

def filter_file(f):
    base, ext = os.path.splitext(f)
    ext = ext[1:]
    return ext == EXT

def process_arg(arg):
    if os.path.isdir(arg):
        vprint('Filtering directory:', arg)
        for f in os.listdir(arg):
            process_arg(os.path.join(arg, f))
    else:
        vprint('Filtering file:', arg)
        if filter_file(arg):
            process(arg)

def process_args():
    for arg in options.files:
        vprint('Processing argument: ', arg)
        process_arg(arg)

if __name__ == '__main__':
    parser = ArgumentParser(usage='%(prog)s [options] filename')
    parser.add_argument('-v', '--verbose', action='store_true', dest='verbose')
    parser.add_argument('files', nargs='+', help='filenames to process')
    options = parser.parse_args()
    process_args()