If you use a Mac, the Iterm2 terminal emulator has an additional protocol that supports rendering images [0]. It basically encodes the image with terminal escape sequences, and also works for animated gifs.

Unfortunately, it seems to not be a standard - it would be neat if there were such a standard, and if other terminals could/would do similarly. It seems like the silliest thing but I like being able to easily indicate when my tests fail or not:

    alias SUCCESS="echo -e '\n\nSUCCESS' \
        && imgcat ~/Pictures/success-100.png \
        || imgcat ~/Pictures/fail-100.png"

    make test && SUCCESS

0: https://www.iterm2.com/documentation-images.html