convert_to_srt.py

from xml.etree import ElementTree as ET
import re

def format_t(time_string, frac_sep = ".", output_frag_sep = "."):
  h = m = secs = ms = 0
  frags = time_string.split(":")
  spart = frags[-1].split(frac_sep)
  if len(spart) == 1:
    s = int(spart[0])
  elif len(spart) == 2:
    s = int(spart[0])
    # small trick - "2.1" should be 2.100, not 2.001
    ms = int(float("0." + spart[1]) * 1000)
  if len(frags) == 2:
    m = int(frags[0])
  elif len(frags) == 3:
    h = int(frags[0])
    m = int(frags[1])
  return "{0:02d}:{1:02d}:{2:02d}{3}{4:03d}".format(h,m,s, output_frag_sep,ms)

def assert_time_format(time_string):
  p = re.compile("\d{2}\:\d{2}:\d{2}[\.\,]\d{3}")
  if p.match(time_string) != None:
    return True
  return False

def convert_to_srt(xmlfile, srtfile):
  with open(xmlfile, "r") as srcf:
    with open(srtfile, "w") as dstf:
      doc = ET.fromstring(srcf.read())
      anno_count = 1
      for anno in doc.findall("annotations/annotation"):
        text_e = anno.find("TEXT")
        t_rects = [x for x in anno.findall("segment/movingRegion/rectRegion")]
        if text_e.text != None and len(t_rects) == 2:
          # add new annotation
          dstf.write("\n{0}\n".format(anno_count))
          time1 = format_t(t_rects[0].attrib["t"])
          time2 = format_t(t_rects[1].attrib["t"])
          if not assert_time_format(time1) or not assert_time_format(time2):
            print("Time is formatted incorrectly for annotation {0}:".format(anno_count))
            print("time1: {0}".format(time1))
            print("time2: {0}".format(time2))
          dstf.write("{0} --> {1}\n".format(time1, time2))
          dstf.write(text_e.text)
          dstf.write("\n")
          anno_count += 1
        else:
          print("Annotation found, but couldn't parse it for some reason:")
          if text_e.text == None:
            print("No text found in the TEXT element")
          if len(t_rects) != 2:
            print("More than 2 rect regions found for some reason...")
          
if __name__ == "__main__":
  import sys
  if len(sys.argv) != 3:
    print("Usage: python convert_to_srt.py xmlfilename.xml srtfilename.srt")
  else:
    _, xmlf, srtf = sys.argv
    convert_to_srt(xmlf, srtf)