parse.py

from datetime import datetime, timedelta

srtFormat = '''{0}
{1} --> {2}
{3}
'''


def srt(index, start, end, text):
    return srtFormat.format(index, start, end, text)


def txt2srt(filepath):
    subtitle_list = []
    with open(filepath, 'r') as file:
        for line in file.readlines():
            timestr = line.split(' ')[0]
            time = datetime.strptime(timestr, '%M:%S.%f')
            text = line[len(timestr):].strip()
            subtitle_list.append({
                'time': time,
                'text': text
            })
    with open(filepath + ".srt", 'w') as file:
        for idx, x in enumerate(subtitle_list):
            srt_index = idx + 1
            start = x['time'].strftime("%H:%M:%S.%f")[:-3]
            if idx == len(subtitle_list) - 1:
                end = (x['time'] + timedelta(minutes=5)).strftime("%H:%M:%S.%f")[:-3]
            else:
                end = subtitle_list[idx + 1]['time'].strftime("%H:%M:%S.%f")[:-3]
            file.write(srt(srt_index, start, end, x['text']) + "\n")


# Press the green button in the gutter to run the script.
if __name__ == '__main__':
    txt2srt("./01-welcome.txt")