Class: Timecode

Inherits:
Object
  • Object
show all
Includes:
Approximately, Comparable
Defined in:
lib/timecode.rb

Defined Under Namespace

Classes: CannotParse, Error, RangeError, WrongFramerate

Constant Summary collapse

VERSION = 
'2.1.0'
DEFAULT_FPS = 
25.0
STANDARD_RATES =

Quoting the Flame project configs here (as of ver. 2013 at least) TIMECODE KEYWORD

Specifies the default timecode format used by the project. Currently supported formats are 23.976, 24, 25, 29.97, 30, 50, 59.94 or 60 fps timecodes.

[23.976, 24, 25, 29.97, 30, 50, 59.94, 60].map do | float |
  Approximately.approx(float, 0.002) # Tolerance of 2 millisecs should do.
end.freeze
NTSC_FPS = 
(30.0 * 1000 / 1001).freeze
FILMSYNC_FPS = 
(24.0 * 1000 / 1001).freeze
ALLOWED_FPS_DELTA = 
(0.001).freeze
COMPLETE_TC_RE = 
/^(\d{2}):(\d{2}):(\d{2}):(\d{2})$/
COMPLETE_TC_RE_24 = 
/^(\d{2}):(\d{2}):(\d{2})\+(\d{2})$/
DF_TC_RE = 
/^(\d{1,2}):(\d{1,2}):(\d{1,2});(\d{2})$/
FRACTIONAL_TC_RE = 
/^(\d{2}):(\d{2}):(\d{2})[\.,](\d{1,8})$/
TICKS_TC_RE = 
/^(\d{2}):(\d{2}):(\d{2}):(\d{3})$/
WITH_FRACTIONS_OF_SECOND = 
"%02d:%02d:%02d.%02d"
WITH_SRT_FRACTION = 
"%02d:%02d:%02d,%02d"
WITH_FRACTIONS_OF_SECOND_COMMA = 
"%02d:%02d:%02d,%03d"
WITH_FRAMES = 
"%02d:%02d:%02d:%02d"
WITH_FRAMES_24 = 
"%02d:%02d:%02d+%02d"

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(total = 0, fps = DEFAULT_FPS) ⇒ Timecode

Initialize a new Timecode object with a certain amount of frames and a framerate will be interpreted as the total number of frames

Raises:



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# File 'lib/timecode.rb', line 68

def initialize(total = 0, fps = DEFAULT_FPS)
  raise WrongFramerate, "FPS cannot be zero" if fps.zero?
  self.class.check_framerate!(fps)
  # If total is a string, use parse
  raise RangeError, "Timecode cannot be negative" if total.to_i < 0
  # Always cast framerate to float, and num of rames to integer
  @total, @fps = total.to_i, fps.to_f
  @value = validate!
  freeze
end

Class Method Details

.add_custom_framerate!(rate) ⇒ Object

Use this to add a custom framerate



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# File 'lib/timecode.rb', line 96

def add_custom_framerate!(rate)
  @custom_framerates ||= []
  @custom_framerates.push(rate)
end

.at(hrs, mins, secs, frames, with_fps = DEFAULT_FPS) ⇒ Object

Initialize a Timecode object at this specfic timecode



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# File 'lib/timecode.rb', line 181

def at(hrs, mins, secs, frames, with_fps = DEFAULT_FPS)
  validate_atoms!(hrs, mins, secs, frames, with_fps)
  total = (hrs*(60*60*with_fps) +  mins*(60*with_fps) + secs*with_fps + frames).round
  new(total, with_fps)
end

.check_framerate!(fps) ⇒ Object

Check the passed framerate and raise if it is not in the list



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# File 'lib/timecode.rb', line 102

def check_framerate!(fps)
  unless supported_framerates.include?(fps)
    supported = "%s and %s are supported" % [supported_framerates[0..-2].join(", "), supported_framerates[-1]]
    raise WrongFramerate, "Framerate #{fps} is not in the list of supported framerates (#{supported})"
  end
end

.from_filename_in_sequence(filename_with_or_without_path, fps = DEFAULT_FPS) ⇒ Object

Parses the timecode contained in a passed filename as frame number in a sequence



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# File 'lib/timecode.rb', line 120

def from_filename_in_sequence(filename_with_or_without_path, fps = DEFAULT_FPS)
  b = File.basename(filename_with_or_without_path)
  number = b.scan(/\d+/).flatten[-1].to_i
  new(number, fps)
end

.from_seconds(seconds_float, the_fps = DEFAULT_FPS) ⇒ Object

create a timecode from the number of seconds. This is how current time is supplied by QuickTime and other systems which have non-frame-based timescales



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# File 'lib/timecode.rb', line 233

def from_seconds(seconds_float, the_fps = DEFAULT_FPS)
  total_frames = (seconds_float.to_f * the_fps.to_f).to_i
  new(total_frames, the_fps)
end

.from_uint(uint, fps = DEFAULT_FPS) ⇒ Object

Some systems (like SGIs) and DPX format store timecode as unsigned integer, bit-packed. This method unpacks such an integer into a timecode.



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# File 'lib/timecode.rb', line 240

def from_uint(uint, fps = DEFAULT_FPS)
  tc_elements = (0..7).to_a.reverse.map do | multiplier |
    ((uint >> (multiplier * 4)) & 0x0F)
  end.join.scan(/(\d{2})/).flatten.map{|e| e.to_i}

  tc_elements << fps
  at(*tc_elements)
end

.new(from = nil, fps = DEFAULT_FPS) ⇒ Object

Use initialize for integers and parsing for strings



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# File 'lib/timecode.rb', line 110

def new(from = nil, fps = DEFAULT_FPS)
  from.is_a?(String) ? parse(from, fps) : super(from, fps)
end

.parse(spaced_input, with_fps = DEFAULT_FPS) ⇒ Object

Parse timecode entered by the user. Will raise if the string cannot be parsed. The following formats are supported:

  • 10h 20m 10s 1f (or any combination thereof) - will be disassembled to hours, frames, seconds and so on automatically

  • 123 - will be parsed as 00:00:01:23

  • 00:00:00:00 - will be parsed as zero TC



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# File 'lib/timecode.rb', line 131

def parse(spaced_input, with_fps = DEFAULT_FPS)
  input = spaced_input.strip

  # Drop frame goodbye
  if (input =~ DF_TC_RE)
    raise Error, "We do not support drop-frame TC"
  # 00:00:00:00
  elsif (input =~ COMPLETE_TC_RE)
    atoms_and_fps = input.scan(COMPLETE_TC_RE).to_a.flatten.map{|e| e.to_i} + [with_fps]
    return at(*atoms_and_fps)
  # 00:00:00+00
  elsif (input =~ COMPLETE_TC_RE_24)
    atoms_and_fps = input.scan(COMPLETE_TC_RE_24).to_a.flatten.map{|e| e.to_i} + [24]
    return at(*atoms_and_fps)
  # 00:00:00.0
  elsif input =~ FRACTIONAL_TC_RE
    parse_with_fractional_seconds(input, with_fps)
  # 00:00:00:000
  elsif input =~ TICKS_TC_RE
    parse_with_ticks(input, with_fps)
  # 10h 20m 10s 1f 00:00:00:01 - space separated is a sum of parts
  elsif input =~ /\s/
    parts = input.gsub(/\s/, ' ').split.reject{|e| e.strip.empty? }
    raise CannotParse, "No atoms" if parts.empty?
    parts.map{|part|  parse(part, with_fps) }.inject{|sum, p| sum + p.total }
  # 10s
  elsif input =~ /^(\d+)s$/
    return new(input.to_i * with_fps, with_fps)
  # 10h
  elsif input =~ /^(\d+)h$/i
    return new(input.to_i * 60 * 60 * with_fps, with_fps)
  # 20m
  elsif input =~ /^(\d+)m$/i
    return new(input.to_i * 60 * with_fps, with_fps)
  # 60f - 60 frames, or 2 seconds and 10 frames
  elsif input =~ /^(\d+)f$/i
    return new(input.to_i, with_fps)
  # Only a bunch of digits, treat 12345 as 00:01:23:45
  elsif (input =~ /^(\d+)$/)
    atoms_len = 2 * 4
    # left-pad input AND truncate if needed
    padded = input[0..atoms_len].rjust(8, "0")
    atoms = padded.scan(/(\d{2})/).flatten.map{|e| e.to_i } + [with_fps]
    return at(*atoms)
  else
    raise CannotParse, "Cannot parse #{input} into timecode, unknown format"
  end
end

.parse_with_fractional_seconds(tc_with_fractions_of_second, fps = DEFAULT_FPS) ⇒ Object

Parse a timecode with fractional seconds instead of frames. This is how ffmpeg reports a timecode



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# File 'lib/timecode.rb', line 203

def parse_with_fractional_seconds(tc_with_fractions_of_second, fps = DEFAULT_FPS)
  fraction_expr = /[\.,](\d+)$/
  fraction_part = ('.' + tc_with_fractions_of_second.scan(fraction_expr)[0][0]).to_f

  seconds_per_frame = 1.0 / fps.to_f
  frame_idx = (fraction_part / seconds_per_frame).floor

  tc_with_frameno = tc_with_fractions_of_second.gsub(fraction_expr, ":%02d" % frame_idx)

  parse(tc_with_frameno, fps)
end

.parse_with_ticks(tc_with_ticks, fps = DEFAULT_FPS) ⇒ Object

Parse a timecode with ticks of a second instead of frames. A ‘tick’ is defined as 4 msec and has a range of 0 to 249. This format can show up in subtitle files for digital cinema used by CineCanvas systems

Raises:



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# File 'lib/timecode.rb', line 218

def parse_with_ticks(tc_with_ticks, fps = DEFAULT_FPS)
  ticks_expr = /(\d{3})$/
  num_ticks = tc_with_ticks.scan(ticks_expr).join.to_i

  raise RangeError, "Invalid tick count #{num_ticks}" if num_ticks > 249

  seconds_per_frame = 1.0 / fps
  frame_idx = ( (num_ticks * 0.004) / seconds_per_frame ).floor
  tc_with_frameno = tc_with_ticks.gsub(ticks_expr, "%02d" % frame_idx)

  parse(tc_with_frameno, fps)
end

.soft_parse(input, with_fps = DEFAULT_FPS) ⇒ Object

Parse timecode and return zero if none matched



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# File 'lib/timecode.rb', line 115

def soft_parse(input, with_fps = DEFAULT_FPS)
  parse(input) rescue new(0, with_fps)
end

.supported_framerates ⇒ Object

Returns the list of supported framerates for this subclass of Timecode



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# File 'lib/timecode.rb', line 91

def supported_framerates
  STANDARD_RATES + (@custom_framerates || [])
end

.validate_atoms!(hrs, mins, secs, frames, with_fps) ⇒ Object

Validate the passed atoms for the concrete framerate



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# File 'lib/timecode.rb', line 188

def validate_atoms!(hrs, mins, secs, frames, with_fps)
  case true
  when hrs > 999
      raise RangeError, "There can be no more than 999 hours, got #{hrs}"
    when mins > 59
      raise RangeError, "There can be no more than 59 minutes, got #{mins}"
    when secs > 59
      raise RangeError, "There can be no more than 59 seconds, got #{secs}"
    when frames >= with_fps
      raise RangeError, "There can be no more than #{with_fps} frames @#{with_fps}, got #{frames}"
  end
end

Instance Method Details

#*(arg) ⇒ Object

Multiply the timecode by a number

Raises:



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# File 'lib/timecode.rb', line 379

def *(arg)
  raise RangeError, "Timecode multiplier cannot be negative" if (arg < 0)
  self.class.new(@total*arg.to_i, @fps)
end

#+(arg) ⇒ Object

add number of frames (or another timecode) to this one



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# File 'lib/timecode.rb', line 351

def +(arg)
  if (arg.is_a?(Timecode) && framerate_in_delta(arg.fps, @fps))
    self.class.new(@total+arg.total, @fps)
  elsif (arg.is_a?(Timecode))
    raise WrongFramerate, "You are calculating timecodes with different framerates"
  else
    self.class.new(@total + arg, @fps)
  end
end

#-(arg) ⇒ Object

Subtract a number of frames



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# File 'lib/timecode.rb', line 368

def -(arg)
  if (arg.is_a?(Timecode) &&  framerate_in_delta(arg.fps, @fps))
    self.class.new(@total-arg.total, @fps)
  elsif (arg.is_a?(Timecode))
    raise WrongFramerate, "You are calculating timecodes with different framerates"
  else
    self.class.new(@total-arg, @fps)
  end
end

#/(arg) ⇒ Object

Get the number of times a passed timecode fits into this time span (if performed with Timecode) or a Timecode that multiplied by arg will give this one



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# File 'lib/timecode.rb', line 391

def /(arg)
  arg.is_a?(Timecode) ?  (@total / arg.total) : self.class.new(@total / arg, @fps)
end

#<=>(other_tc) ⇒ Object

Timecodes can be compared to each other



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# File 'lib/timecode.rb', line 396

def <=>(other_tc)
  if framerate_in_delta(fps, other_tc.fps)
    self.total <=> other_tc.total
  else
    raise WrongFramerate, "Cannot compare timecodes with different framerates"
  end
end

#adjacent_to?(another) ⇒ Boolean

Tells whether the passes timecode is immediately to the left or to the right of that one with a 1 frame difference

Returns:

  • (Boolean) 


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# File 'lib/timecode.rb', line 363

def adjacent_to?(another)
  (self.succ == another) || (another.succ == self)
end

#coerce(to) ⇒ Object 



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# File 'lib/timecode.rb', line 250

def coerce(to)
  me = case to
    when String
      to_s
    when Integer
      to_i
    when Float
      to_f
    else
      self
  end
  [me, to]
end

#convert(new_fps) ⇒ Object

Convert to different framerate based on the total frames. Therefore, 1 second of PAL video will convert to 25 frames of NTSC (this is suitable for PAL to film TC conversions and back).



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# File 'lib/timecode.rb', line 322

def convert(new_fps)
  self.class.new(@total, new_fps)
end

#fps ⇒ Object

get FPS



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# File 'lib/timecode.rb', line 275

def fps
  @fps
end

#frame_interval ⇒ Object

get frame interval in fractions of a second



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# File 'lib/timecode.rb', line 300

def frame_interval
  1.0/@fps
end

#framerate_in_delta(one, two) ⇒ Object

Validate that framerates are within a small delta deviation considerable for floats



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# File 'lib/timecode.rb', line 423

def framerate_in_delta(one, two)
  (one.to_f - two.to_f).abs <= ALLOWED_FPS_DELTA
end

#frames ⇒ Object

get the number of frames



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# File 'lib/timecode.rb', line 280

def frames
  value_parts[3]
end

#hours ⇒ Object

get the number of hours



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# File 'lib/timecode.rb', line 295

def hours
  value_parts[0]
end

#inspect ⇒ Object

:nodoc:



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# File 'lib/timecode.rb', line 79

def inspect # :nodoc:
  string_repr = if (framerate_in_delta(fps, 24))
    WITH_FRAMES_24 % value_parts
  else
    WITH_FRAMES % value_parts
  end
  "#<Timecode:%s (%dF@%.2f)>" % [string_repr, total, fps]
end

#minutes ⇒ Object

get the number of minutes



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# File 'lib/timecode.rb', line 290

def minutes
  value_parts[1]
end

#seconds ⇒ Object

get the number of seconds



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# File 'lib/timecode.rb', line 285

def seconds
  value_parts[2]
end

#succ ⇒ Object

Get the next frame



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# File 'lib/timecode.rb', line 385

def succ
  self.class.new(@total + 1, @fps)
end

#to_f ⇒ Object

get total frames as float



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# File 'lib/timecode.rb', line 341

def to_f
  @total
end

#to_i ⇒ Object

get total frames as integer



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# File 'lib/timecode.rb', line 346

def to_i
  @total
end

#to_s ⇒ Object

Get formatted SMPTE timecode. Hour count larger than 99 will roll over to the next remainder (129 hours will produce “29:00:00:00:00”). If you need the whole hour count use ‘to_s_without_rollover`



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# File 'lib/timecode.rb', line 329

def to_s
  vs = value_parts
  vs[0] = vs[0] % 100 # Rollover any values > 99
  WITH_FRAMES % vs
end

#to_s_without_rollover ⇒ Object

Get formatted SMPTE timecode. Hours might be larger than 99 and will not roll over



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# File 'lib/timecode.rb', line 336

def to_s_without_rollover
  WITH_FRAMES % value_parts
end

#to_seconds ⇒ Object

get the timecode as a floating-point number of seconds (used in Quicktime)



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# File 'lib/timecode.rb', line 315

def to_seconds
  (@total / @fps)
end

#to_uint ⇒ Object

get the timecode as bit-packed unsigned 32 bit int (suitable for DPX and SGI)



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# File 'lib/timecode.rb', line 305

def to_uint
  elements = (("%02d" * 4) % [hours,minutes,seconds,frames]).split(//).map{|e| e.to_i }
  uint = 0
  elements.reverse.each_with_index do | p, i |
    uint |= p << 4 * i
  end
  uint
end

#total ⇒ Object

get total frame count



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# File 'lib/timecode.rb', line 270

def total
  to_f
end

#with_frames_as_fraction(pattern = WITH_FRACTIONS_OF_SECOND) ⇒ Object Also known as: with_fractional_seconds

FFmpeg expects a fraction of a second as the last element instead of number of frames. Use this method to get the timecode that adheres to that expectation. The return of this method can be fed to ffmpeg directly.

Timecode.parse("00:00:10:24", 25).with_frames_as_fraction #=> "00:00:10.96"



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# File 'lib/timecode.rb', line 408

def with_frames_as_fraction(pattern = WITH_FRACTIONS_OF_SECOND)
  vp = value_parts.dup
  vp[-1] = (100.0 / @fps) * vp[-1]
  pattern % vp
end

#with_srt_fraction ⇒ Object

SRT uses a fraction of a second as the last element instead of number of frames, with a comma as the separator

Timecode.parse("00:00:10:24", 25).with_srt_fraction #=> "00:00:10,96"



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# File 'lib/timecode.rb', line 418

def with_srt_fraction
  with_frames_as_fraction(WITH_SRT_FRACTION)
end

#zero? ⇒ Boolean

is the timecode at 00:00:00:00

Returns:

  • (Boolean) 


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# File 'lib/timecode.rb', line 265

def zero?
  @total.zero?
end