Like many other blogs, this one uses so-called “globally recognised avatars”. or “gravatars” to provide each commenter with their own unique image which will match from site to site, and from visit to visit, so long as they use the same email address when commenting. It’s a clever idea – the supplied address is encrypted using a one-way hash (so there’s no easy way to get the email address from the hash), and that unique hash is used to return an image associated with the user.

If they’re so inclined, users can create an account at www.gravatar.com and set their own custom image. If they don’t then the site will algorithmically create an image for them, based on their email hash, ensuring that they get the same image every time they use that email address. There are a few types of algorithmically generated images – a geometric pattern, a monster, or a generated face (which they refer to as a “wavatar”). It is the latter that I use on this site, and it is the latter than is the source of the apparently sarcastic comments.

Wavatars are made up of several pieces that canchange with each hash: a background, a “face” shape, eyebrows, eyes and mouth. The problem is the mouth in particular, though the eyebrows can also be an issue: several of the mouth variations look unhappy, and the eyebrows can appear as a frown. An unhappy, frowny wavatar can give a completely different feel to even the nicest of comments. In fact the nicer the comment, the more sarcastic it seems to become.

Let’s look at some examples. The images below are all genuine gravatars for real comments that have been left on this blog, or on my webcomic. I’ve posted just the image and the opening or closing words of the comments, but omitted the full text and the posters’ details. See what your sarcasm detectors think about this lot:

When seeing wavatars like these, I can’t help but feel that there’s an implicit “…NOT!” that should be added, regardless of how complimentary the comment is.

The only real solution to this would be for the gravatar developers to change their palette of mouths to replace the miserable, downturned, grimaced variants with happier versions. Alternatively, if you do decide to leave a comment on my blog or comic, you might want to set your own gravatar image just in case. Or at the very least, choose your words to sound less sarcastic if they do get paired with a grumpy visage.