It's not a problem to have this handled in the shell such that the output is rendered in such a way as to please the terminal. You can do this manually (e.g. append a "| display-jpeg-in-terminal" command to the pipeline), or use a magic bytes based file viewer.

Look at "run-mailcap" or its shortcuts like "see". It does basically that, and can also be fed through standard input (which covers the piping situation).