Ffmpeg\avconv compression as much as possible without quality loss?

Question

fmpeg

Good afternoon
There are 20 jpeg pictures 2304 * 1296 each picture differs from the previous one by 5-10%
The photo is a static object, the difference is only in the noise from the video camera
Total size of 20 pictures 5mb
combines into one movie and size 4.5mb
avconv -y -r 1 -f image2 -i /tmp/1/foo-%03d.jpeg /tmp/1/test.mp4
Why is the mp4 file so big?
Are there other codec formats that compress better without severe quality loss?
90% of the background does not change.
Are there any codecs that highlight the general scene / background and only transmit the difference in frames?