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Old Dec 09, 2012, 05:05 PM
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How To Make Time Lapse Video - Video Frame Rate Method

The #16 now has two functions that can be used to make time lapse videos, namely Time-Lapse Photos and Video Frame Rate. But how is it done? Here's the easiest way I've found when using the Video Frame Rate method with AviDemux v2.5.6, the free cross-platform editor that runs on Windows, Linux, and MAC computers.

Video Frame Rate method:

This method simply records at your choice of a slower frame rate, and then you play it back at a faster rate to get the speed up. In addition to the normal 30 fps frame rate, v0.58 and higher firmware gives options for recording at 5, 10, 15, 20, and 25 fps. The video playback speed can be increased with many editing tools, but I'll just give details on doing it with the free editor, AviDemux, which can directly import the camera's native MOV or AVI files, and output the video at a different frame rate with no re-encoding of the video (i.e. no quality loss). I keep the playback rate at 30 fps to keep things simple. This will produce videos that playback with the following speed-ups:

Recorded Frame Rate ... Speed-up (at 30 fps playback)
5 fps* .................................... 6x*
10 fps .................................... 3x
15 fps .................................... 2x
20 fps .................................. 1.5x
25 fps .................................. 1.2x

*NOTE: The 5 fps frame rate has inherent unusual recording and playback properties which causes the audio and video tracks to both play back at 30 fps, which results in the video being accelerated by a factor of 6. The result is the accelerated video is finished long before the audio track, giving the impression some video was lost. In reality, the entire video portion is there during playback, but it is drastically out of sync with the audio. This is a bug with only the 5fps setting, and a fix for it has not yet been identified. The other frame rate settings will play the video in sync with the audio, but the motion will also move in "jump steps" due to the slower frame rate. A work around is to strip the audio off the 5 fps native video, and the playback will stop when the video is finished.

The process is pretty simple:
  1. Boot AviDemux and load your video.

  2. Set the Video output mode to "Copy" and the output Format to "MP4" to assure compatibility with most players and editors (see Pic #1)

  3. Except when the recorded frame rate is set for 5 sec., select "Video/Frame Rate..." menu item, and at the prompt, check the "Use Custom Value" box and enter "30" in the Frame Rate box. Click "OK" to continue (see Pic #2). Note: This step can be omitted when using the 5 fps rate because it will already play back at 30 fps!

  4. Select the "Audio/Main Track" menu item and toggle the output to "None". Click "OK" to remove the sound track from the final video (see Pic #3). This needs to be done because the audio will be out of sync in the sped-up video.

  5. Select "File/Save/Save Video" menu item (see Pin #4). When the prompt appears, give your output file a name and destination folder. Be SURE to add the ".MP4" suffix to the file name (e.g. TestFile[U].MP4/u])! The program does not do this for you. The file will be intact if you forget, but you will need to rename the file with the "MP4" suffix before it can be played or edited.

  6. That's it! You're Done. The video will be output in a matter of seconds since there is no re-encoding to be done.
This method produces "mild" speed up and is best suited for action sequences less than 30 minutes recording time, or when smoother motion is desired. For longer duration events, the Time Lapse Photo Method may be the better choice.
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Last edited by Tom Frank; May 06, 2013 at 12:05 PM. Reason: added additional explanation for the 5 fps setting
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