From subsecret
Timelapse from video
Instead of using a camera with native support for timelapse, it is possible to use the normal video recording mode and later convert the video into a timelapse.
Step 1: Extract pictures from video
ffmpeg is very useful for this purpose. You need to specify
-i : Input file path -s : size of result picture (hd720 and hd1080 are the most common) -r : The number of pictures to be extracted per second of movie
Example:
ffmpeg -i 00000.MTS -s hd1080 -sameq -r 3 imageA-%4d.jpeg
If you want to combine multiple movies into the same timelapse, just change the A in the output name to B or later latter in the alphabet. That way it will be easy to combine them later. Example:
ffmpeg -i 00000.MTS -s hd1080 -sameq -r 3 imageA-%4d.jpeg ffmpeg -i 00001.MTS -s hd1080 -sameq -r 3 imageB-%4d.jpeg ffmpeg -i 00002.MTS -s hd1080 -sameq -r 3 imageC-%4d.jpeg
