A method to use music data or metadata of music data regardless of an offset discrepancy including steps of: determining code values according to a volume transition in every certain period starting from a coding start position on a time axis in music data; and generating a characteristic pattern indicating a characteristic of a volume transition of the music data using a series of the code values determined over plural periods. The code value can be configured to indicate whether an average volume in a certain period is increased or decreased from an average volume in a previous period, for example.