Convert subtitles from srv3 to vtt format

srv3-to-vtt.py

#!/usr/bin/env python3

from os import write
import xml.etree.ElementTree as ET
import sys


class paragraph():
    def __init__(self, t, d, text):
        self.t = int(t if t else 0)
        self.d = int(d if d else 0)
        self.text = text.strip() if text else ""

def vtt_file_from(input):
    return input.replace(".srv3", ".vtt")

def format_timestamp(ms):
    hh = ms / 3600000
    ms = ms % 3600000
    mm = ms / 60000
    ms = ms % 60000
    ss = ms / 1000
    ms = ms % 1000
    return "%02d:%02d:%02d.%03d" % (hh, mm, ss, ms)

def generate_vtt_file(name, list_of_p):
    with open(name, "w") as of:
        of.write("WEBVTT\n\n")
        for p in list_of_p:
            if len(p.text) > 0:
                time_line = ("%s --> %s\n" % (format_timestamp(p.t), format_timestamp(p.t + p.d)))
                of.write(time_line)
                of.write(p.text + "\n\n")
    pass


def convert_srv3_to_vtt(input):
    doc = ET.parse(input)
    root = doc.getroot()
    list_of_p = []
    if root.tag == "timedtext" and root.get("format") == "3":
        for root_child in root:
            if root_child.tag == 'body':
                body = root_child
                for body_child in body:
                    if body_child.tag == "p":
                        p = body_child
                        t = p.get("t")
                        d = p.get("d")
                        text = "".join(p.itertext())
                        list_of_p.append(paragraph(t, d, text))
        pass
    last_t = 0xFFFFFFFF
    for p in reversed(list_of_p):
        if len(p.text) > 0:
            if p.t + p.d > last_t:
                p.d = last_t - p.t
            last_t = p.t
    generate_vtt_file(vtt_file_from(input), list_of_p)
    pass

args = sys.argv
for input in args[1:]:
    print(("input: %s" % input))
    convert_srv3_to_vtt(input)
    input