CHARACTERIZING AUDIO USING TRANSCHROMAGRAMS

Methods, systems and apparatus to characterize audio using transchromagrams are disclosed. An example method includes generating, by executing one or more instructions on a processor, a set of transition matrices based on a plurality of time frames of the audio data, each of the plurality of transition matrices generated based on a different pair of time frames in the plurality of time frames, and indicating probabilities that anterior musical notes in an anterior time frame of the pair transition to posterior musical notes in a posterior time frame of the pair, generating, by executing one or more instructions on a processor, a data structure representing how the audio data changes statistically between the plurality of time frames based on the set of transition matrices, and causing, by executing one or more instructions on a processor, a database to store the data structure within metadata that describes the audio data.