As an old-school signal processing person, "wavelet" and "FM" are throwing me for a loop. I can see FM is named for the authors. "wavelet" - I don't see at first glance what the name means or if it's related to the signal processing concept.
Yes, the 'wavelet tree' (and other wavelet thingies in succinct data structures) are rather unfortunately named. It ranks right up there with 'wavefunction collapse' in procedural generation.
