vtc-ex

A SMPTE Timecode Library for Elixir

Demo

Let's take a quick look at how we can use this library!

# It's easy to make a new 23.98 NTSC timecode. We use the with_frames constructor here 
# since timecode is really a human-readable way to represent frame count.
iex> tc = Vtc.Timecode.with_frames!("17:23:13:02", Vtc.Rate.f23_98)
<17:23:00:02 @ <23.98 NTSC NDF>>

# We can get all sorts of ways to represent the timecode.
iex> Vtc.Timecode.timecode(tc)
"17:23:00:02"

iex> Vtc.Timecode.frames(tc)
1501922

iex> tc.seconds
751711961 <|> 12000

iex> Vtc.Timecode.runtime(tc, 3)
"17:24:15.676"

iex> Vtc.Timecode.premiere_ticks(tc)
15915544300656000

iex(3)> Vtc.Timecode.feet_and_frames(tc)
"93889+10"

# We can inspect the framerate.
iex> tc.rate.ntsc
:NonDrop  

iex> tc.rate.playback
24000 <|> 1001

iex> Vtc.Framerate.timebase(tc.rate)
24

# Parsing is flexible

# Partial timecode:
iex> Vtc.Timecode.with_frames!("3:12", Vtc.Rate.f23_98)
<03:00:00:12 @ <23.98 NTSC NDF>>

# Frame count:
iex> Vtc.Timecode.with_frames!(24, Vtc.Rate.f23_98)    
<00:00:01:00 @ <23.98 NTSC NDF>>

# Seconds:
iex> Vtc.Timecode.with_seconds!(1.5, Vtc.Rate.f23_98)
<00:05:23:04 @ <23.98 NTSC NDF>>

# Runtime:
iex> Vtc.Timecode.with_seconds!("00:05:23.5", Vtc.Rate.f23_98)
<00:00:01:12 @ <23.98 NTSC NDF>>

# Premiere Ticks:
iex> Vtc.Timecode.with_premiere_ticks!(254016000000, Vtc.Rate.f23_98)
<00:00:01:00 @ <23.98 NTSC NDF>>

# Feet and Frames:
iex> Vtc.Timecode.with_frames!("1+08", Vtc.Rate.f23_98)
<00:00:01:00 @ <23.98 NTSC NDF>>

# We can make dropframe timecode for 29.97 or 59.94 using one of the pre-set 
# framerates.
iex> drop_frame = Vtc.Timecode.with_frames!(15000, Vtc.Rate.f29_97_Df)
<00:08:20;18 @ <29.97 NTSC DF>>

# We can make new timecodes with arbitrary framerates if we want:
iex> rate = Vtc.Framerate.new!(240, :None)
<240.0 fps>
iex> Vtc.Timecode.with_frames!("01:00:00:00", rate)
<01:00:00:00 @ <240.0 fps>>

# We do the same thing NTSC framerates / timebases.
iex> rate = Vtc.Framerate.new!(240, :NonDrop)
<239.76 NTSC NDF>

Features

• SMPTE Conventions:
  • NTSC
  • Drop-Frame
  • Interlaced timecode
• Timecode Representations:
  • Timecode | '01:00:00:00'
  • Frames | 86400
  • Seconds | 3600.0
  • Runtime | '01:00:00.0'
  • Rational | 18018/5
  • Feet+Frames | '5400+00'
    • 35mm, 4-perf
    • 35mm, 3-perf
    • 35mm, 2-perf
    • 16mm
  • Premiere Ticks | 15240960000000
• Operations:
  • Comparisons (==, <, <=, >, >=)
  • Add
  • Subtract
  • Scale (multiply and divide)
  • Divmod
  • Modulo
  • Negative
  • Absolute
  • Rebase (recalculate frame count at new framerate)
• Flexible Parsing:
  • Partial timecodes | '1:12'
  • Partial runtimes | '1.5'
  • Negative string values | '-1:12', '-3+00'
  • Poorly formatted tc | '1:13:4'
• Built-in consts for common framerates.
• Range type for working with and comparing frame ranges.

Installation

If available in Hex, the package can be installed by adding vtc to your list of dependencies in mix.exs:

def deps do
  [
    {:vtc, "~> 0.1"}
  ]
end