I'm currently working in a project that involves converting large series of .jpg (>6000) into video format. These frames (320x240) are stored in folders at a rate of 2.5fps. Generating a couple of folders every hour that need to be converted ASAP.
For now I've tried copying the folder to a ram disk and using avconv which takes about a minute.
Here is my command:
avconv -threads auto -y -r 2.51 -i %03d-capture.jpg -s 320x240 -r 25 video.mpeg
ffmpeg with x264 should work faster.
ffmpeg -threads auto -y -framerate 2.51 -i %03d-capture.jpg -r 25 -preset ultrafast video.mp4
I've removed the size option, since if they don't need to be resized, you can save time by bypassing the scaler call.