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frameToSmpte

frameToSmpte

Description

Converts a frame number into a SMPTE timecode string, taking into account the SMPTE_Offset value of the active clip.

The SMPTE_Offset value of the active clip specifies the timecode start for the data on the clip. It is there so that frame 1 of your data corresponds to the starting timecode of your take. Without it, your frame numbers would end up large and cumbersome.

If you want to ignore the SMPTE_Offset in the computation, specify the -ignoreOffset flag. You may wish to do this when computing a SMPTE_Offset of your own, for instance. In that situation, you wouldn't want the existing offset value in the computation.

The frames (FF) portion of the timecode string will go from 0 to 24, 25, or 30 depending on the current timecode standard (Film, PAL, and NTSC respectively). As your scene frame rate may be a higher multiple of those standard rates (e.g. 120 fps for NTSC), the sub-frame portion indicates the "in between frame" of the frame passed in.

Functional area

System

Command syntax

Syntax

frameToSmpte frame[-ignoreOffset]

Arguments

NameTypeRequiredComments
frameintegeryesThe frame number to convert into SMPTE timecode

Flags

NameFlag argumentsArgument typeExclusive toComments
ignoreOffset0By default, the active clip's SMPTE_Offset value is added to the frame argument to produce a final timecode value. This flag causes the offset to be ignored causing a straight frame to timecode conversion.

Return value

string

A SMPTE timecode string in the format HH:MM:SS:FF(SubFrame).

Examples

// Print the timecode values of the start and end frames of 
// the play range
int $playStart = `getPlayStart`;
int $playEnd = `getPlayEnd`;
string $playStartStr = `frameToSmpte $playStart`;
string $playEndStr = `frameToSmpte $playEnd`;
print $playStartStr;
print $playEndStr;

Additional information

Note that, given there are two fields per video frame, as shown in the following example output:

Field 1 subframes are of the format HH:MM:SS:FF(SubFrame), with a colon between the seconds and frames; but

Field 2 subframes are of the format HH:MM:SS.FF(SubFrame), with a period between the seconds and frames.

(Frame rates that use drop frames use a semi-colon ( ; ) and a comma ( , ) in the equivalent positions.)

For example, with NTSC non-drop timecode at 119.88 fps, the subframes will look like this:

 00:00:00:00(0) Field 1 of frame 0
 00:00:00:00(1) Field 1 of frame 0
 00:00:00.00(2) Field 2 of frame 0
 00:00:00.00(3) Field 2 of frame 0
 00:00:00:01(0) Field 1 of frame 1
 00:00:00:01(1) Field 1 of frame 1
 00:00:00.01(2) Field 2 of frame 1
 00:00:00.01(3) Field 2 of frame 1
 Reducing to 59.940 fps gives:
 00:00:00:00(0) Field 1 of frame 0
 00:00:00.00(1) Field 2 of frame 0
 00:00:00:01(0) Field 1 of frame 1
 00:00:00.01(1) Field 2 of frame 1

Related commands


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