As the title states, I want to match the timestamp and text lines of a .srt file subtitles.
some of these files are not formatted properly, so I need something to work with almost all of them.
the correct formatting of a file is like this:
1
00:00:02,160 --> 00:00:04,994
You really don't remember
what happened last year?
2
00:00:06,440 --> 00:00:07,920
- School. Now.
- I dropped out.
3
00:00:08,120 --> 00:00:10,510
- Get your diploma, I'll get mine.
- What you doing?
4
00:00:10,680 --> 00:00:13,514
- Studying.
- You taking your GED? All right, Fi.
and the regex pattern that I came up with is working very well for this kind of files.
as I said, some of the files are not formatted properly, some of them don’t have the line number, some of them don’t have a new line after each subtitle line and the regex that I came up with does not work properly for those.
There are other questions like this that have already been answered, but I want to match each timestamp and text line in a separate matching-group. so my groups for the first line of the mentioned example would be something like this:
group 1: 00:00:02,160
group 2: 00:00:04,994
group 3: You really don't remember\nwhat happened last year?
this is what I’ve got so far:
LINE_RE = (
# group 1:
r"^\s*(\d+:\d+:\d+,\d+)" # line starts with any number of whitespace
# and followed by a time format like 00:00:00,000
r"(?:\s*-{2,3}>\s*)" # non-matching group for ' --> '
# matches one or more of - follwed by a >
# group 2:
r"(\d+:\d+:\d+,\d+)\s*\n" # time format again,
# ended with any number of whitespace and a \n
# group 3:
r"([\s\S]*?(?:^\s*$|\d+:\d+:\d+,\d+|^\s*\d+\s*\n))"
# matches any character, until it hits an empty line, a line with only a number in it or a timestamp
)
I think my exact problem is in the last non-matching group, it does not work properly when the next line is not an empty line.
this is an example file, I did some mangling in the file so I could show the problem better.
>Solution :
In that case, you can match the lines that start with a timestamp like pattern, and capture all lines that do not start with either a newline and a single digit or another timestamp like pattern.
^\s*(\d+:\d+:\d+,\d+)[^\S\n]+-->[^\S\n]+(\d+:\d+:\d+,\d+)((?:\n(?!\d+:\d+:\d+,\d+\b|\n+\d+$).*)*)
The pattern in parts matches:
^Start of string\s*Match optional whitspace chars(\d+:\d+:\d+,\d+)Capture group 1, match a timestamp like pattern[^\S\n]+-->[^\S\n]+Match-->between 1 or more spaces(\d+:\d+:\d+,\d+)Capture group 2, same pattern as for group 1(Capture group 3(?: Non capture group–\nMatch a newline(?!Negative lookahead, assert what is to the right is not\d+:\d+:\d+,\d+\b|\n+\d+$Match either a timestamp or 1+ newlines followed by only digits
)Close lookahead.*Match the whole line
)*Close the non capture group and optionally repeat it
)Close group 3
See a regex demo.