Dept of Familiar Obfuscation

[libertango]

I was just poking about on Flickr, and saw something it took me a moment to decipher:

"hbw"

Anyone want to take a shot at it?

(Hint: It's sometimes spelled out in captions, but only about 14% of the time.)

Comments

[intelligentrix.livejournal.com]

Height by width?
Bah.