Captured frames, clip length, and still storage
Playback uses every captured frame once. The compression factor is interval multiplied by playback rate; the endpoint frame can make clip length slightly longer than duration divided by that factor. Storage describes still files rather than the encoded video.
To estimate the encoded clip size after its duration is known, the Video File Size Calculator uses video and audio bitrates.
The formula
The schedule includes a first frame at time zero and every scheduled frame at or before the capture duration. Thus an exact interval at the endpoint is included. Start-to-start interval already includes exposure and camera delay within each scheduled period.
Worked example
A 60 minute capture with a 5 s interval includes 721 frames, starting at zero and ending at 3,600 s. At 30 fps, playback lasts 24.033 s. Ten MB per still image requires 7.21 GB, and nominal time compression is 150×.
How to use this calculator
- Enter capture duration, start-to-start shot interval using the units shown.
- Set playback frame rate, average image file size.
- Calculate and review playback duration alongside the supporting quantities.
Match the interval definition to the camera
Some interval settings describe time from one exposure start to the next; other equipment may describe the pause after an exposure. This calculator uses start-to-start timing. Confirm that the exposure and processing time fit inside that interval. If frames are skipped because the camera is busy, the actual sequence has fewer images than the scheduled count.
Capture files and finished movie differ
Average image size can be estimated from test frames using the intended format and settings. RAW and JPEG files have different storage needs, and sizes may vary across the scene. The completed video depends on codec and bitrate, so it cannot be estimated by summing still-image sizes alone. Battery capacity and storage limits should be checked for the complete capture period.
Assumptions & limitations
What this calculation assumes
- A frame is taken at time zero and at each interval through the inclusive endpoint.
What to keep in mind
- Excludes skipped shots, variable file size, encoding bitrate, battery limits, and interval drift.
Common questions
Why is there one extra frame?
The schedule includes a frame at the start before any interval has elapsed, plus each later scheduled frame.
Is this the finished video file size?
No. Storage is for the captured still images. Video encoding requires a separate bitrate and duration estimate.
What if the capture duration is zero?
The schedule still includes its first frame at time zero. Playback therefore contains one frame.
Sources & further reading
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