  It is known that human speech and certain animal vocalizations can convey
meaningful content because we can decipher the content that a given utterance
does convey. This paper explores an alternative approach to determining whether
a signal is meaningful, one that analyzes only the signal itself and is
independent of what the conveyed meaning might be. We devise a method that
takes a waveform as input and outputs a score indicating its degree of
`meaningfulness`. We cluster contiguous portions of the input to minimize the
total description length, and then take the length of the code of the assigned
cluster labels as meaningfulness score. We evaluate our method empirically,
against several baselines, and show that it is the only one to give a high
score to human speech in various languages and with various speakers, a
moderate score to animal vocalizations from birds and orcas, and a low score to
ambient noise from various sources.
