TSProcessor.rb

require 'rake'
require 'time'

Encoding.default_internal = Encoding::UTF_8
Encoding.default_external = Encoding::UTF_8

class Timestamp
  attr_reader :from, :to
  def initialize from, to
    @from = from.to_i
    @to = to.to_i
  end
  def to_inc
    @to + 1
  end
  def duration
    to_inc - from
  end
end

class Fixnum
  def to_time fps:, delay: 0
    (self / fps - delay / 1000.0).round(3)
  end
end

class SubtitleLine
  attr_reader :dialog
  def initialize line
    @text = line
    @dialog = line['Dialogue'] ? true : false
    if @dialog
      @timepart = line[/([0-9:.]{10,10}),([0-9:.]{10,10})/]
      @start = Time.parse("1/1/1970 #{$1} UTC").to_f
      @end = Time.parse("1/1/1970 #{$2} UTC").to_f
    end
  end
  def offset ms
    @start += ms
    @end += ms
    @start = 0 if @start < 0
    @end = 0 if @end < 0
    start_text = Time.at(@start).utc.strftime('%-H:%M:%S.%2N')
    end_text = Time.at(@end).utc.strftime('%-H:%M:%S.%2N')
    @text[@timepart] = "#{start_text},#{end_text}"
  end
  def disable!
    return if !@dialog
    @dialog = false
    @text = '; ' + @text
  end
  def between? from:, to:
    @start > from && @start < to
  end
  def to_s
    @text
  end
end

class TSProcessor
  include FileUtils
  def initialize time: 'time.txt', fps: 24000.0/1001
    @time = time
    @fps = fps
    @timecode = []
  end

  def map &block
    parse_timecode
    @tc.map &block
  end

  def parse_timecode
    return if [email protected]?
    raise IOError.new("Timecode file not exists") if !File.exists? @time
    @timecode = File.readlines(@time).map do |line|
      m = line.match /(\d+)\D+(\d+)/
      m.nil? ? nil : Timestamp.new(m[1], m[2])
    end.compact
  end

  def aac source:, target: nil, delay: 0
    parse_timecode
    raise IOError if !File.exists? source
    ext = File.extname(source)
    base = File.basename(source, ext)
    target = base + '.new.m4a' if target.nil?
    if ext['.aac']
      base = '_' + base + '.aacmk'
      ext = '.m4a'
      mp4 = base + ext
      sh "muxer -i #{source} -o #{mp4}" if !File.exists? mp4
      source = mp4
    end
    # Produce slices
    diff = 0
    name = ''
    mp4_files = @timecode.map do |t|
      from = t.from.to_time(fps: @fps) + diff
      to = t.to_inc.to_time(fps: @fps)
      duration = to - from
      sh "mp4box -splitx #{from}:#{to} #{source}"
      name = "#{base}_#{from.truncate}_#{to.truncate}#{ext}"
      `mediainfo -f #{name} | grep Duration | head -n 1`[/ (\d+)\Z/]
      actual_duration = $1.to_f / 1000.0
      diff = actual_duration - duration
      puts 'Ideal: %.3f, Actual: %.3f, Diff: %.3f' % [duration, actual_duration, diff]
      " -cat #{name} "
    end
    # Concatinating
    mv target, target+'.bak' if File.exists? target
    if mp4_files.size == 1
      mv name, target
    else
      sh "mp4box #{mp4_files.join} #{target}"
    end
  end

  def avs source: 'main.avs', target: nil
    parse_timecode
    ext = File.extname(source)
    base = File.basename(source, ext)
    target = base + '.trim.avs' if target.nil?
    File.write target, @timecode.map{ |t| "trim(#{t.from},#{t.to})" }.join(' + ')
  end

  def delogo source: 'main.avs', target: nil, fade: 0, offset1: 0, offset2: 0
    parse_timecode
    ext = File.extname(source)
    base = File.basename(source, ext)
    target = base + '.delogo.avs' if target.nil?
    current = 0
    File.open target, 'w' do |f|
      @timecode.each do |tc|
        length = tc.duration
        f << 'EraseLOGO(logoFile'
        f << ', fadein=%d, fadeout=%d' % [fade, fade] if fade != 0
        f << ', start=%d, end=%d)' % [current + offset1, current + length - offset2]
        f << "\n"
        current += length
      end
    end
  end

  def sub source: 'main.kingyubi.ass', target: nil, delay: 0
    parse_timecode
    raise IOError if !File.exists? source
    target = source.ext('.new.ass') if target.nil?
    # Convert to Time Range
    start_time = 0.0
    timerange = @timecode.map do |t|
      s = t.from.to_time fps: @fps
      e = t.to_inc.to_time fps: @fps
      offset = start_time - s
      start_time += e - s
      {:s => s, :e => e, :o => offset}
    end
    subs = File.readlines(source).map { |l| SubtitleLine.new l }
    subs.each do |s|
      next if !s.dialog
      catch :offset do
        timerange.each do |t|
          if s.between? from: t[:s], to: t[:e]
            s.offset t[:o]
            throw :offset
          end
        end
        s.disable!
      end
    end
    File.open(target, 'w') do |f|
      subs.each { |s| f << s.to_s }
    end
  end
end