restore-ntsc

#!/usr/bin/env python3
# -*- python -*-
#
# Copyright 2019 by Chris Osborn <fozztexx@fozztexx.com>
#
# This file is part of viddin.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License at <http://www.gnu.org/licenses/> for
# more details.

import argparse
import os
import re
import datetime
import sys
import tempfile
import shutil
import viddin
import subprocess

MULTIPLIER = 25 / (24000.0 / 1001)

def build_argparser():
  parser = argparse.ArgumentParser()
  parser.add_argument("file", help="input file")
  parser.add_argument("--normalize", action="store_true", help="normalize audio")
  parser.add_argument("--volume", help="adjust audio to specified level")
  return parser

def subTimecode(tc):
  ft = viddin.formatChapter(tc)
  ft = ft[:-4] + ":" + ft[-3:] + ","
  return ft

def slowVideo(path, tempdir):
  cmd = ["mediainfo", "--Inform=Video;%FrameRate%", path]
  inrate = subprocess.check_output(cmd).strip()
  if not len(inrate):
    print("Not a constant frame rate")
    return None
  inrate = float(inrate)
  outrate = 24000.0 / 25025 * inrate

  vtemp = os.path.join(tempdir, os.path.basename(path))
  cmd = ["mkvmerge", "-o", vtemp,
         "--default-duration", "0:%0.3ffps" % (outrate),
         "-d", "0", path]
  viddin.runCommand(cmd, debugFlag=True)
  return vtemp

def slowAudio(path, tempdir):
  atemp, ext = os.path.splitext(os.path.basename(path))
  atemp += ".ac3"
  atemp = os.path.join(tempdir, atemp)
  cmd = ["ffmpeg", "-y",
         "-i", path, "-vn", "-acodec", "ac3", "-ab", "448k",
         "-filter:a", "asetpts='25025/24000*(PTS-STARTPTS)',aresample=48000:min_comp=0.01" +
         ":comp_duration=1:max_soft_comp=100000000:min_hard_comp=0.3", atemp]
  viddin.runCommand(cmd)
  return atemp

def normalizeAudio(path, volume):
  atemp, ext = os.path.splitext(path)
  atemp += "-adj" + ext
  cmd = ["adjust-volume"]
  if not volume is None:
    cmd.extend(["--volume", volume])
  cmd.append(path)
  viddin.runCommand(cmd)
  return atemp

def expandChapters(path):
  cmd = ["edit-chapters", "--fix", "--multiplier", "%0.3f" % (MULTIPLIER), path]
  viddin.runCommand(cmd)
  return

def expandSubtitles(path, tempdir, tinfo):
  outpath, ext = os.path.splitext(os.path.basename(path))
  subs = []
  for track in tinfo.subtitles:
    subpath = outpath + "_%i" % (track['rv_track_id'])
    subpath = os.path.join(tempdir, subpath)
    cmd = ["mkvextract", "tracks", path, "%i:%s" % (track['rv_track_id'], subpath + ".sub")]
    viddin.runCommand(cmd)
    out_idx = open(subpath + "-exp.idx", "w")
    for line in open(subpath + ".idx", "r"):
      if line.startswith("timestamp:"):
        fields = line.split()
        tcstr = fields[1]
        tcstr = tcstr[:-5] + "." + tcstr[-4:-1]
        tc = viddin.decodeTimecode(tcstr)
        tc *= MULTIPLIER
        tcstr = subTimecode(tc)
        fields[1] = tcstr
        line = " ".join(fields) + "\n"
      out_idx.write(line)
    subs.append(subpath + ".idx")
    os.rename(subpath + "-exp.idx", subpath + ".idx")
  return subs

def main():
  args = build_argparser().parse_args()
  path = args.file
  tempdir = os.path.dirname(path)
  tempdir = tempfile.mkdtemp(dir=tempdir)

  vfile = viddin.Media(path)
  tinfo = vfile.getTitleInfo()
  vtemp = slowVideo(path, tempdir)
  atemp = slowAudio(path, tempdir)
  if args.normalize:
    atemp = normalizeAudio(atemp, args.volume)
  expandChapters(vtemp)
  subs = expandSubtitles(vtemp, tempdir, tinfo)

  outpath, ext = os.path.splitext(path)
  subpath, _ = os.path.splitext(os.path.basename(path))
  subpath = os.path.join(tempdir, subpath)
  outpath += "-NTSC" + ".mkv"
  cmd = ["mkvmerge", "-o", outpath, "--no-audio", "--no-subtitles", vtemp, atemp]
  if len(tinfo.subtitles):
    for track in tinfo.subtitles:
      cmd.extend(["--default-track", "0:%i" % (int(track['default_track'])),
                  "--forced-track", "0:%i" % (int(track['forced_track'])),
                  "--language", "0:%s" % (track['language']),
                  subpath + "_%i.idx" % (track['rv_track_id'])])
  viddin.runCommand(cmd)
  shutil.rmtree(tempdir)
  return

if __name__ == '__main__':
  exit(main() or 0)