+def parse_dfxp_time_expr(time_expr):
+ if not time_expr:
+ return 0.0
+
+ mobj = re.match(r'^(?P<time_offset>\d+(?:\.\d+)?)s?$', time_expr)
+ if mobj:
+ return float(mobj.group('time_offset'))
+
+ mobj = re.match(r'^(\d+):(\d\d):(\d\d(?:\.\d+)?)$', time_expr)
+ if mobj:
+ return 3600 * int(mobj.group(1)) + 60 * int(mobj.group(2)) + float(mobj.group(3))
+
+
+def srt_subtitles_timecode(seconds):
+ return '%02d:%02d:%02d,%03d' % (seconds / 3600, (seconds % 3600) / 60, seconds % 60, (seconds % 1) * 1000)
+
+
+def dfxp2srt(dfxp_data):
+ _x = functools.partial(xpath_with_ns, ns_map={'ttml': 'http://www.w3.org/ns/ttml'})
+
+ def parse_node(node):
+ str_or_empty = functools.partial(str_or_none, default='')
+
+ out = str_or_empty(node.text)
+
+ for child in node:
+ if child.tag == _x('ttml:br'):
+ out += '\n' + str_or_empty(child.tail)
+ elif child.tag == _x('ttml:span'):
+ out += str_or_empty(parse_node(child))
+ else:
+ out += str_or_empty(xml.etree.ElementTree.tostring(child))
+
+ return out
+
+ dfxp = xml.etree.ElementTree.fromstring(dfxp_data.encode('utf-8'))
+ out = []
+ paras = dfxp.findall(_x('.//ttml:p'))
+
+ for para, index in zip(paras, itertools.count(1)):
+ begin_time = parse_dfxp_time_expr(para.attrib['begin'])
+ end_time = parse_dfxp_time_expr(para.attrib.get('end'))
+ if not end_time:
+ end_time = begin_time + parse_dfxp_time_expr(para.attrib['dur'])
+ out.append('%d\n%s --> %s\n%s\n\n' % (
+ index,
+ srt_subtitles_timecode(begin_time),
+ srt_subtitles_timecode(end_time),
+ parse_node(para)))
+
+ return ''.join(out)
+
+