I have a webcam that works as a v4l2 device.

What is the most convenient way to capture either a stop-motion or time-lapse video?

N.B.

stop-motion and time-lapse are related but conceptually different.

Time-lapse is where you take a photo of a scene at a set interval and then combine it into a video (that looks like it's going really fast).

Stop-motion is where you control the scene and take an image for every change you make, to form an animation (eg Wallace and Grommit).

An application for time-lapse needs to be able to take a photo at a set interval.

Capturing a zillion images.

The first step is capturing images. Let's imagine you want to take a photo once every 10 seconds and save that into a directory sitting on your desktop

mkdir ~/Desktop/cap

cd ~/Desktop/cap

We use streamer to do the capture so let's install it:

sudo apt-get install streamer

And now we want to capture

streamer -o 0000.jpeg -s 300x200 -j 100 -t 2000 -r 1

-t is the number of frames we want to capture. -r is frames per second. So this should grab one frame every second. If you compress that down into a 30fps video, one minute of capture becomes 2 seconds of video. You'll want to tune this appropriately depending on how much output video you want.

That line will give you 2000 images, it'll take half an hour to record and, at 30fps, will generate just over 1 minute of video.

Putting it all together

I'm going to use ffmpeg. There are many different ways of putting it together including mencoder but I just prefer ffmpeg's outlook on life. After installing it (sudo apt-get install ffmpeg) just wang out this:

ffmpeg -r 30 -i %04d.jpeg -s hd480 -vcodec libx264 -vpre hq time-lapse.mp4

The quality settings there aren't anything like that of my webcam so you might want to play around with the options a lot more to get a better encode, but that should generate you a nice 30fps video, compressed up in x264.

You might want to play around with the framerate (-r) but I wouldn't go below 15fps.

To capture every X amount of seconds from a webcam use motion.

Install motion

sudo apt-get install motion or sudo aptitude install motion

Configure motion for every X amount of seconds

sudo nano /etc/motion/motion.conf

Change the variables minimum_frame_time and snapshot_interval to the same amount of seconds you wish to take the picture with the webcam.

10 Minutes = 600 Seconds

20 Minutes = 1200 Seconds

30 Minutes = 1800 Seconds

1 Hour = 3600 Seconds

2 Hours = 7200 Seconds and so on...

run motion with sudo motion stop it with CTRL+C

NOTE - Configure motion.conf to save the files in another directory than the default /tmp. For example your home folder. Since going to /tmp needs more privileges. You will also find many useful options in the motion.conf for many other things you might like.

gTimelapse (Download Link)

An application for capturing images to generate timelapse videos, built on gPhoto2 and wxWidgets libraries.

Compile instructions

Download the source from the sourceforge website

in a terminal type the following:

cd Downloads 

gunzip gtimelapse-0.1.tar.gz

tar -xvf gtimelapse-0.1.tar

cd gtimelapse

sudo apt-get install build-essential libgphoto2-2-dev libwxbase2.8-dev libwxgtk2.8-dev gphoto2

./configure

make

sudo make install

To run the application type

gtimelapse &

n.b. 1

gphoto2 --list-cameras | more

n.b. 2

see this blog for further useful info

lists all compatible devices that the application supports

n.b. 3

I've read the gphoto2 does not support webcams - I'll leave this answer visible anyway just in-case anyone wants to try this answer with a decent digital camera instead of a webcam.

I've used Stopmotion to do this, it's in the software center. You can also capture with Cheese, but you have to alter Cheese's configuration to boost the max number of images. I found it easiest to just use Stopmotion for the entire process.