Vtc.Timecode (vtc v0.3.9) View Source
Represents the frame at a particular time in a video.
New Timecode values are created with the with_seconds/3
and with_frames/2
, and
other function prefaced by with_*
.
Link to this section Summary
Types
As round/0
, but includes :off
option to disable rounding entirely. Not all
functions exposed by this module make logical sense without some form of rouding, so
:off
will not be accepted by all functions.
Type returned by with_seconds/3
and with_frames/3
.
Valid values for rounding options.
Timecode
type.
Functions
Returns the absolute value of tc
.
Adds two timecodoes together using their real-world seconds representation. When the
rates of a
and b
are not equal, the result will inheret the framerat of a
and
be rounded to the seconds representation of the nearest whole-frame at that rate.
Returns whether a
is greater than, equal to, or less than b
in terms of real-world
seconds.
Divides dividend
by divisor
. The result will inherit the framerate of dividend
and rounded to the nearest whole-frame based on the :round
option.
Divides the total frame count of dividend
by divisor
and returns both a quotient
and a remainder as Timecode values.
Returns the number of feet and frames this timecode represents if it were shot on 35mm 4-perf film (16 frames per foot). ex: '5400+13'.
Returns the number of frames that would have elapsed between 00:00:00:00 and this timecode.
Scales a
by b
. The result will inheret the framerat of a
and be rounded to the
seconds representation of the nearest whole-frame based on the :round
option.
As the kernel -/1
function.
Returns the number of elapsed ticks this timecode represents in Adobe Premiere Pro.
Rebases the timecode to a new framerate.
As rebase/2
, but raises on error.
Devides the total frame count of dividend
by devisor
, rounds the quotient down,
and returns the remainder rounded to the nearest frame.
Runtime Returns the true, real-world runtime of the timecode in HH:MM:SS.FFFFFFFFF format.
The individual sections of a timecode string as i64 values.
Subtracts two timecodoes together using their real-world seconds representation. When
the rates of a
and b
are not equal, the result will inheret the framerat of a
and be rounded to the seconds representation of the nearest whole-frame at that rate.
Returns the the formatted SMPTE timecode: (ex: 01:00:00:00). Drop frame timecode will be rendered with a ';' sperator before the frames field.
Returns a new Timecode
with a frames/1
return value equal to the frames
arg.
As Timecode.with_frames/3
, but raises on error.
Returns a new Timecode
with a premiere_ticks/1
return value equal
to the ticks arg.
As with_premiere_ticks/3
, but raises on error.
Returns a new Timecode
with a Timecode.seconds
field value equal to the
seconds
arg.
As with_seconds/3
, but raises on error.
Link to this section Types
Specs
maybe_round() :: round() | :off
As round/0
, but includes :off
option to disable rounding entirely. Not all
functions exposed by this module make logical sense without some form of rouding, so
:off
will not be accepted by all functions.
Specs
parse_result() :: {:ok, t()} | {:error, Vtc.Timecode.ParseError.t() | %ArgumentError{__exception__: true, message: term()}}
Type returned by with_seconds/3
and with_frames/3
.
Specs
round() :: :closest | :floor | :ceil
Valid values for rounding options.
:closest
: Round the to the closet whole frame.:floor
: Always round down to the closest whole-frame.:ciel
: Always round up to the closest whole-frame.
Specs
t() :: %Vtc.Timecode{rate: Vtc.Framerate.t(), seconds: Vtc.Utils.Rational.t()}
Timecode
type.
Fields
seconds: The real-world seconds elapsed since 01:00:00:00 as a rational value. (Note: The Ratio module automatically will coerce itself to an integer whenever possible, so this value may be an integer when exactly a whole-second value).
rate: the Framerate of the timecode.
Link to this section Functions
Specs
Returns the absolute value of tc
.
Examples
iex> tc = Timecode.with_frames!("-01:00:00:00", Rates.f23_98())
iex> Timecode.abs(tc) |> inspect()
"<01:00:00:00 @ <23.98 NTSC NDF>>"
iex> tc = Timecode.with_frames!("01:00:00:00", Rates.f23_98())
iex> Timecode.abs(tc) |> inspect()
"<01:00:00:00 @ <23.98 NTSC NDF>>"
Specs
add( a :: t(), b :: t() | Vtc.Source.Frames.t(), opts :: [{:round, maybe_round()}] ) :: t()
Adds two timecodoes together using their real-world seconds representation. When the
rates of a
and b
are not equal, the result will inheret the framerat of a
and
be rounded to the seconds representation of the nearest whole-frame at that rate.
b
May be any value that implements the Frames
protocol, such as a timecode string,
and will be assumed to be the same framerate as a
. This is mostly to support quick
scripting. This function will raise if there is an error parsing b
.
Options
- round: How to round the result with respect to whole-frames when mixing
framerates. Default:
:closest
.
Examples
Two timecodes running at the same rate:
iex> a = Timecode.with_frames!("01:00:00:00", Rates.f23_98())
iex> b = Timecode.with_frames!("01:30:21:17", Rates.f23_98())
iex> Timecode.add(a, b) |> inspect()
"<02:30:21:17 @ <23.98 NTSC NDF>>"
Two timecodes running at different rates:
iex> a = Timecode.with_frames!("01:00:00:00", Rates.f23_98())
iex> b = Timecode.with_frames!("00:00:00:02", Rates.f47_95())
iex> Timecode.add(a, b) |> inspect()
"<01:00:00:01 @ <23.98 NTSC NDF>>"
Using a timcode and a bare string:
iex> a = Timecode.with_frames!("01:00:00:00", Rates.f23_98())
iex> Timecode.add(a, "01:30:21:17") |> inspect()
"<02:30:21:17 @ <23.98 NTSC NDF>>"
Specs
compare(a :: t(), b :: t() | Vtc.Source.Frames.t()) :: :lt | :eq | :gt
Returns whether a
is greater than, equal to, or less than b
in terms of real-world
seconds.
b
May be any value that implements the Frames
protocol, such as a timecode string,
and will be assumed to be the same framerate as a
. This is mostly to support quick
scripting. This function will raise if there is an error parsing b
.
Examples
Using two timecodes, 01:00:00:00
NTSC is greater than 01:00:00:00
true because it
represents more real-world time.
iex> a = Timecode.with_frames!("01:00:00:00", Rates.f23_98())
iex> b = Timecode.with_frames!("01:00:00:00", Rates.f24())
iex> :gt = Timecode.compare(a, b)
Using a timcode and a bare string:
iex> timecode = Timecode.with_frames!("01:00:00:00", Rates.f23_98())
iex> :eq = Timecode.compare(timecode, "01:00:00:00")
Specs
div( dividend :: t(), divisor :: Ratio.t() | number(), opts :: [{:round, maybe_round()}] ) :: t()
Divides dividend
by divisor
. The result will inherit the framerate of dividend
and rounded to the nearest whole-frame based on the :round
option.
Options
- round: How to round the result with respect to whole-frame values. Defaults to
:floor
to matchdivmod
and the expected meaning ofdiv
to mean integer division in elixir.
Examples
iex> dividend = Timecode.with_frames!("01:00:00:00", Rates.f23_98())
iex> Timecode.div(dividend, 2) |> inspect()
"<00:30:00:00 @ <23.98 NTSC NDF>>"
iex> dividend = Timecode.with_frames!("01:00:00:00", Rates.f23_98())
iex> Timecode.div(dividend, 0.5) |> inspect()
"<02:00:00:00 @ <23.98 NTSC NDF>>"
Specs
divrem( dividend :: t(), divisor :: Ratio.t() | number(), opts :: [round_frames: round(), round_remainder: round()] ) :: {t(), t()}
Divides the total frame count of dividend
by divisor
and returns both a quotient
and a remainder as Timecode values.
The quotient returned is equivalent to Timecode.div/3
with the :round
option set
to :floor
.
Options
round_frames: How to round the frame count before doing the divrem operation. Default:
:closest
.round_remainder: How to round the remainder frames when a non-whole frame would be the result. Default:
:closest
.
Examples
iex> dividend = Timecode.with_frames!("01:00:00:01", Rates.f23_98())
iex> Timecode.divrem(dividend, 4) |> inspect()
"{<00:15:00:00 @ <23.98 NTSC NDF>>, <00:00:00:01 @ <23.98 NTSC NDF>>}"
Specs
Returns the number of feet and frames this timecode represents if it were shot on 35mm 4-perf film (16 frames per foot). ex: '5400+13'.
Options
- round: How to round the internal frame count before conversion.
What it is
On physical film, each foot contains a certain number of frames. For 35mm, 4-perf film (the most common type on Hollywood movies), this number is 16 frames per foot. Feet-And-Frames was often used in place of Keycode to quickly reference a frame in the edit.
Where you see it
For the most part, feet + frames has died out as a reference, because digital media is not measured in feet. The most common place it is still used is Studio Sound Departments. Many Sound Mixers and Designers intuitively think in feet + frames, and it is often burned into the reference picture for them.
Telecine.
Sound turnover reference picture.
Sound turnover change lists.
Specs
Returns the number of frames that would have elapsed between 00:00:00:00 and this timecode.
Options
- round: How to round the resulting frame number.
What it is
Frame number / frames count is the number of a frame if the timecode started at 00:00:00:00 and had been running until the current value. A timecode of '00:00:00:10' has a frame number of 10. A timecode of '01:00:00:00' has a frame number of 86400.
Where you see it
Frame-sequence files: 'my_vfx_shot.0086400.exr'
FCP7XML cut lists:
<timecode> <rate> <timebase>24</timebase> <ntsc>TRUE</ntsc> </rate> <string>01:00:00:00</string> <frame>86400</frame> <!-- <====THIS LINE--> <displayformat>NDF</displayformat> </timecode>
Specs
mult(a :: t(), b :: Ratio.t() | number(), opts :: [{:round, maybe_round()}]) :: t()
Scales a
by b
. The result will inheret the framerat of a
and be rounded to the
seconds representation of the nearest whole-frame based on the :round
option.
Options
- round: How to round the result with respect to whole-frame values. Defaults to
:closest
.
Examples
iex> a = Timecode.with_frames!("01:00:00:00", Rates.f23_98())
iex> Timecode.mult(a, 2) |> inspect()
"<02:00:00:00 @ <23.98 NTSC NDF>>"
iex> a = Timecode.with_frames!("01:00:00:00", Rates.f23_98())
iex> Timecode.mult(a, 0.5) |> inspect()
"<00:30:00:00 @ <23.98 NTSC NDF>>"
Specs
As the kernel -/1
function.
- Makes a positive
tc
value negative. - Makes a negative
tc
value positive.
Examples
iex> tc = Timecode.with_frames!("01:00:00:00", Rates.f23_98())
iex> Timecode.negate(tc) |> inspect()
"<-01:00:00:00 @ <23.98 NTSC NDF>>"
iex> tc = Timecode.with_frames!("-01:00:00:00", Rates.f23_98())
iex> Timecode.negate(tc) |> inspect()
"<01:00:00:00 @ <23.98 NTSC NDF>>"
Specs
Returns the number of elapsed ticks this timecode represents in Adobe Premiere Pro.
Options
- round: How to round the resulting ticks.
What it is
Internally, Adobe Premiere Pro uses ticks to divide up a second, and keep track of how far into that second we are. There are 254016000000 ticks in a second, regardless of framerate in Premiere.
Where you see it
Premiere Pro Panel functions and scripts.
FCP7XML cutlists generated from Premiere:
<clipitem id="clipitem-1"> ... <in>158</in> <out>1102</out> <pproTicksIn>1673944272000</pproTicksIn> <pproTicksOut>11675231568000</pproTicksOut> ... </clipitem>
Specs
rebase(t(), Vtc.Framerate.t()) :: parse_result()
Rebases the timecode to a new framerate.
The real-world seconds are recalculated using the same frame count as if they were
being played back at new_rate
instead of timecode.rate
.
Examples
iex> timecode = Timecode.with_frames!("01:00:00:00", Rates.f23_98())
iex> {:ok, rebased} = Timecode.rebase(timecode, Rates.f47_95())
iex> Timecode.to_string(rebased)
"<00:30:00:00 @ <47.95 NTSC NDF>>"
Specs
rebase!(t(), Vtc.Framerate.t()) :: t()
As rebase/2
, but raises on error.
Specs
rem( dividend :: t(), divisor :: Ratio.t() | number(), opts :: [round_frames: round(), round_remainder: round()] ) :: t()
Devides the total frame count of dividend
by devisor
, rounds the quotient down,
and returns the remainder rounded to the nearest frame.
Options
round_frames: How to round the frame count before doing the rem operation. Default:
:closest
.round_remainder: How to round the remainder frames when a non-whole frame would be the result.
Examples
iex> dividend = Timecode.with_frames!("01:00:00:01", Rates.f23_98())
iex> Timecode.rem(dividend, 4) |> inspect()
"<00:00:00:01 @ <23.98 NTSC NDF>>"
Specs
Runtime Returns the true, real-world runtime of the timecode in HH:MM:SS.FFFFFFFFF format.
Arguments
- precision: The number of places to round to. Extra trailing 0's will still be trimmed.
What it is
The formatted version of seconds. It looks like timecode, but with a decimal seconds value instead of a frame number place.
Where you see it
• Anywhere real-world time is used.
• FFMPEG commands:
ffmpeg -ss 00:00:30.5 -i input.mov -t 00:00:10.25 output.mp4
Note
The true runtime will often diverge from the hours, minutes, and seconds value of the timecode representation when dealing with non-whole-frame framerates. Even drop-frame timecode does not continuously adhere 1:1 to the actual runtime. For instance, <01:00:00;00 @ <29.97 NTSC DF>> has a true runtime of '00:59:59.9964', and <01:00:00:00 @ <23.98 NTSC NDF>> has a true runtime of '01:00:03.6'
Specs
sections(t(), opts :: [{:round, round()}]) :: Vtc.Timecode.Sections.t()
The individual sections of a timecode string as i64 values.
Specs
sub( a :: t(), b :: t() | Vtc.Source.Frames.t(), opts :: [{:round, maybe_round()}] ) :: t()
Subtracts two timecodoes together using their real-world seconds representation. When
the rates of a
and b
are not equal, the result will inheret the framerat of a
and be rounded to the seconds representation of the nearest whole-frame at that rate.
b
May be any value that implements the Frames
protocol, such as a timecode string,
and will be assumed to be the same framerate as a
. This is mostly to support quick
scripting. This function will raise if there is an error parsing b
.
Options
- round: How to round the result with respect to whole-frames when mixing
framerates. Default:
:closest
.
Examples
Two timecodes running at the same rate:
iex> a = Timecode.with_frames!("01:30:21:17", Rates.f23_98())
iex> b = Timecode.with_frames!("01:00:00:00", Rates.f23_98())
iex> Timecode.sub(a, b) |> inspect()
"<00:30:21:17 @ <23.98 NTSC NDF>>"
When b
is greater than a
, the result is negative:
iex> a = Timecode.with_frames!("01:00:00:00", Rates.f23_98())
iex> b = Timecode.with_frames!("02:00:00:00", Rates.f23_98())
iex> Timecode.sub(a, b) |> inspect()
"<-01:00:00:00 @ <23.98 NTSC NDF>>"
Two timecodes running at different rates:
iex> a = Timecode.with_frames!("01:00:00:02", Rates.f23_98())
iex> b = Timecode.with_frames!("00:00:00:02", Rates.f47_95())
iex> Timecode.sub(a, b) |> inspect()
"<01:00:00:01 @ <23.98 NTSC NDF>>"
Using a timcode and a bare string:
iex> a = Timecode.with_frames!("01:30:21:17", Rates.f23_98())
iex> Timecode.sub(a, "01:00:00:00") |> inspect()
"<00:30:21:17 @ <23.98 NTSC NDF>>"
Specs
Returns the the formatted SMPTE timecode: (ex: 01:00:00:00). Drop frame timecode will be rendered with a ';' sperator before the frames field.
Options
- round: How to round the resulting frames field.
What it is
Timecode is used as a human-readable way to represent the id of a given frame. It is formatted to give a rough sense of where to find a frame: {HOURS}:{MINUTES}:{SECONDS}:{FRAME}. For more on timecode, see Frame.io's excellent post on the subject.
Where you see it
Timecode is ubiquitous in video editing, a small sample of places you might see timecode:
- Source and Playback monitors in your favorite NLE.
- Burned into the footage for dailies.
- Cut lists like an EDL.
Specs
Specs
with_frames(Vtc.Source.Frames.t(), Vtc.Framerate.t()) :: parse_result()
Returns a new Timecode
with a frames/1
return value equal to the frames
arg.
Arguments
frames: A value which can be represented as a frame number / frame count. Must implement the
Frames
protocol.rate: Frame-per-second playback value of the timecode.
Options
- round: How to round the result with regards to whole-frames.
Examples
Accepts timecode strings...
iex> Timecode.with_frames("01:00:00:00", Rates.f23_98) |> inspect()
"{:ok, <01:00:00:00 @ <23.98 NTSC NDF>>}"
... feet+frames strings...
iex> Timecode.with_frames("5400+00", Rates.f23_98) |> inspect()
"{:ok, <01:00:00:00 @ <23.98 NTSC NDF>>}"
... integers...
iex> Timecode.with_frames(86400, Rates.f23_98) |> inspect()
"{:ok, <01:00:00:00 @ <23.98 NTSC NDF>>}"
... and integer strings.
iex> Timecode.with_frames("86400", Rates.f23_98) |> inspect()
"{:ok, <01:00:00:00 @ <23.98 NTSC NDF>>}"
Specs
with_frames!(Vtc.Source.Frames.t(), Vtc.Framerate.t()) :: t()
As Timecode.with_frames/3
, but raises on error.
Specs
with_premiere_ticks( Vtc.Source.PremiereTicks.t(), Vtc.Framerate.t(), opts :: [{:round, maybe_round()}] ) :: parse_result()
Returns a new Timecode
with a premiere_ticks/1
return value equal
to the ticks arg.
Arguments
ticks: Any value that can represent the number of ticks for a given timecode. Must implement the
PremiereTicks
protocol.rate: Frame-per-second playback value of the timecode.
Options
- round: How to round the result with regards to whole-frames.
Examples
Accetps integers.
iex> Timecode.with_premiere_ticks(254_016_000_000, Rates.f23_98) |> inspect()
"{:ok, <00:00:01:00 @ <23.98 NTSC NDF>>}"
Specs
with_premiere_ticks!( Vtc.Source.PremiereTicks.t(), Vtc.Framerate.t(), opts :: [{:round, maybe_round()}] ) :: t()
As with_premiere_ticks/3
, but raises on error.
Specs
with_seconds( Vtc.Source.Seconds.t(), Vtc.Framerate.t(), opts :: [{:round, maybe_round()}] ) :: parse_result()
Returns a new Timecode
with a Timecode.seconds
field value equal to the
seconds
arg.
Arguments
seconds: A value which can be represented as a number of real-world seconds. Must implement the
Seconds
protocol.rate: Frame-per-second playback value of the timecode.
Options
- round: How to round the result with regards to whole-frames.
Examples
Accetps runtime strings...
iex> Timecode.with_seconds("01:00:00.5", Rates.f23_98) |> inspect()
"{:ok, <00:59:56:22 @ <23.98 NTSC NDF>>}"
... floats...
iex> Timecode.with_seconds(3600.5, Rates.f23_98) |> inspect()
"{:ok, <00:59:56:22 @ <23.98 NTSC NDF>>}"
... integers...
iex> Timecode.with_seconds(3600, Rates.f23_98) |> inspect()
"{:ok, <00:59:56:10 @ <23.98 NTSC NDF>>}"
... integer Strings...
iex> Timecode.with_seconds("3600", Rates.f23_98) |> inspect()
"{:ok, <00:59:56:10 @ <23.98 NTSC NDF>>}"
... and float strings.
iex> Timecode.with_seconds("3600.5", Rates.f23_98) |> inspect()
"{:ok, <00:59:56:22 @ <23.98 NTSC NDF>>}"
Specs
with_seconds!( Vtc.Source.Seconds.t(), Vtc.Framerate.t(), opts :: [{:round, maybe_round()}] ) :: t()
As with_seconds/3
, but raises on error.
Specs
with_seconds_round_to_frame( Vtc.Utils.Rational.t(), Vtc.Framerate.t(), maybe_round() ) :: Vtc.Utils.Rational.t()