Parsing srt subtitles

Question

I want to parse srt subtitles:

    1
    00:00:12,815 --> 00:00:14,509
    Chlapi, jak to jde s
    těma pracovníma světlama?.

    2
    00:00:14,815 --> 00:00:16,498
    Trochu je zesilujeme.

    3
    00:00:16,934 --> 00:00:17,814
    Jo, sleduj.

Every item into structure. With this regexs:

A:

RE_ITEM = re.compile(r'(?P<index>\d+).'
    r'(?P<start>\d{2}:\d{2}:\d{2},\d{3}) --> '
    r'(?P<end>\d{2}:\d{2}:\d{2},\d{3}).'
    r'(?P<text>.*?)', re.DOTALL)

B:

RE_ITEM = re.compile(r'(?P<index>\d+).'
    r'(?P<start>\d{2}:\d{2}:\d{2},\d{3}) --> '
    r'(?P<end>\d{2}:\d{2}:\d{2},\d{3}).'
    r'(?P<text>.*)', re.DOTALL)

And this code:

    for i in Subtitles.RE_ITEM.finditer(text):
    result.append((i.group('index'), i.group('start'), 
             i.group('end'), i.group('text')))

With code B I have only one item in array (because of greedy .*) and with code A I have empty 'text' because of no-greedy .*?

How to cure this?

Thanks

Answer 1

Why not use pysrt?

Answer 2

I became quite frustrated with srt libraries available for Python (often because they were heavyweight and eschewed language-standard types in favour of custom classes), so I've spent the last year or so working on my own srt library. You can get it at https://github.com/cdown/srt.

I tried to keep it simple and light on classes (except for the core Subtitle class, which more or less just stores the SRT block data). It can read and write SRT files, and turn noncompliant SRT files into compliant ones.

Here's a usage example with your sample input:

>>> import srt, pprint
>>> gen = srt.parse('''\
... 1
... 00:00:12,815 --> 00:00:14,509
... Chlapi, jak to jde s
... těma pracovníma světlama?.
... 
... 2
... 00:00:14,815 --> 00:00:16,498
... Trochu je zesilujeme.
... 
... 3
... 00:00:16,934 --> 00:00:17,814
... Jo, sleduj.
... 
... ''')
>>> pprint.pprint(list(gen))
[Subtitle(start=datetime.timedelta(0, 12, 815000), end=datetime.timedelta(0, 14, 509000), index=1, proprietary='', content='Chlapi, jak to jde s\ntěma pracovníma světlama?.'),
 Subtitle(start=datetime.timedelta(0, 14, 815000), end=datetime.timedelta(0, 16, 498000), index=2, proprietary='', content='Trochu je zesilujeme.'),
 Subtitle(start=datetime.timedelta(0, 16, 934000), end=datetime.timedelta(0, 17, 814000), index=3, proprietary='', content='Jo, sleduj.')]