Merging images into movie using FFmpeg

Let's say that you have a number of images, named image001.jpeg, image002.jpeg, image003.jpeg etc., and you want to merge them into a single movie, for example to create a time-lapse video. FFmpeg is a great commend-line tool for doing this kind of stuff. To use FFmpeg to create the movie "outmovie.mp4", with 25 frames per second and reasonable quality, enter

ffmpeg -i image%03d.jpeg -sameq -r 25 outmovie.mp4

Note the format image%03d.jpeg, indicating that the numbering of the files has three digits with (possible) leading zeros. To set the output bitrate explicitly to for example 64 kbits/s, use the switch "-b 64k" rather than "-sameq". See the FFmpeg documentation for lots of other possibilities.