Make a time lapse from a video.

Posted by: msaeger

Make a time lapse from a video. - 02/01/2012 02:32

I am trying to find a way to make a time lapse like video from a 8 hour video so I can condense the long video into something short. Probably shouldn't really be called a time lapse but I don't know what else to call it. I just need to capture a frame every second or so and make it into a video.

All I have been able to find is how to do time lapse photography.
Posted by: LittleBlueThing

Re: Make a time lapse from a video. - 02/01/2012 10:05

avisplit ?

-t Split the input file based on time/framecode (hh:mm:ss.ms)
-c Together with -t. Merge all segments into one AVI-File again instead generating seperate files.

a command line with many thousands of -t entries may blow up ... try it.
Posted by: larry818

Re: Make a time lapse from a video. - 02/01/2012 15:32

Or many command lines, winders command lines can only be 8191 characters long.
Posted by: mtempsch

Re: Make a time lapse from a video. - 02/01/2012 16:22

Hmm, I recall seeing someone do something of that nature using VLC's command line client, causing it to spit out a snapshot every Nth frame,
but that was with input from a webcam - not sure if it'd work with from a file.
They then used some other tool to create a movie based on the snapshots, but I'd imagine that is a lesser issue.

This was it, possibly worth playing with?
Posted by: wfaulk

Re: Make a time lapse from a video. - 02/01/2012 19:42

You should be able to use VirtualDub and have it change the frame rate.
Posted by: tonyc

Re: Make a time lapse from a video. - 03/01/2012 00:12

Since it sounds like you want a pretty hefty speed-up (not just 1.5x or 2x) it's probably best to do something that will actually drop the frames, such as mencoder, which would look something like:

Code:
mencoder -nosound -ovc lavc -lavcopts vcodec=mpeg4:vqscale=3
-vf framestep=30 -fps 900 -ofps 30 -o outfile.avi infile.avi


Assuming the input was at 30 fps and you want a 30x speedup. It requires re-encoding, which will degrade the quality a bit, but sometimes it can be tough to playback a 30fps video at 900fps. Adjust the framestep, fps, and ofps to match the parameters for your source video.