A Beginner’s Guide to SMPTE Timecode

If you have ever seen a digital clock running at the bottom of a video screen, you have seen SMPTE timecode. But it is more than just a clock—it is the language that keeps audio, video, and lighting in perfect sync.

What does SMPTE stand for?

SMPTE stands for the Society of Motion Picture and Television Engineers. They are the global body that sets standards for film and video technology.

Reading the Code

Timecode is represented as an 8-digit set of numbers:

This breaks down as:

• 01 (Hours): The hour count (often starts at 01:00:00:00 for the first reel or program start).
• 24 (Minutes): 0-59 minutes.
• 10 (Seconds): 0-59 seconds.
• 12 (Frames): The individual image number. This counts up to the frame rate (e.g., 24, 25, or 30) before rolling over to the next second.

LTC vs. VITC

Historically, timecode was recorded in two ways:

• LTC (Longitudinal Timecode): Recorded as an audible audio screech on an audio track. You can only read it while the tape is playing.
• VITC (Vertical Interval Timecode): Embedded visually into the static of the video signal (in the blanking interval). This allowed editors to read the timecode even when the tape was paused.

In the modern digital age, timecode is now metadata embedded directly into the file header of your QuickTime or MXF files.