ffmpeg: Replace part of a video by a jpg file for 5 seconds

Sometimes I have a video in which I like to discard the video sequence for five seconds between second 11 and second 16 (as an example) and instead incorporate an image from a jpg file that is displayed during that time and leaving the audio sequence intact. Would be great if someone told me an apt command line for this. Thanks in advance :) UPDATE 20200906: The solution should not re-encode the entire video in order to rapidly process large video files with a short image-overlay.