Comment 12 for bug 1747558

I found that, in fact, libjpeg8 is only a dependency package for libjpeg-turbo8.

user@lubuntu:~$ dpkg -l | grep libjpeg
ii libjpeg-turbo8:amd64 1.4.2-0ubuntu3.1 amd64 IJG JPEG compliant runtime library.
ii libjpeg-turbo8:i386 1.4.2-0ubuntu3.1 i386 IJG JPEG compliant runtime library.
ii libjpeg8:amd64 8c-2ubuntu8 amd64 Independent JPEG Group's JPEG runtime library (dependency package)
ii libjpeg8:i386 8c-2ubuntu8 i386 Independent JPEG Group's JPEG runtime library (dependency package)

So, the systems are using libjpeg-turbo8. The string "Premature end of JPEG file" exists also in libjpeg-turbo8 code:

https://github.com/libjpeg-turbo/libjpeg-turbo/search?q=Premature+end+of+JPEG+file&unscoped_q=Premature+end+of+JPEG+file