Patent ID: 7295985

Claim:
A music data compression method comprising the steps of: receiving music data including a sequence of pieces of performance event information each formed of note information including a plurality of types of parameters; and converting each of the pieces of performance event information of the music data to another form of performance event information including status information corresponding to a matching or mismatching pattern in note information between a piece of performance event information and an immediately preceding one of the pieces of performance event information, and at least one mismatching parameter, if any among the plurality of types of parameters included in the note information of the performance event information concerned, said at least one mismatching parameter each having a value thereof mismatching with that of a corresponding parameter included in the note information of the immediately preceding performance event information, wherein said another form of performance event information does not include any matching parameter among the plurality of types of parameters included in the note information of the performance event information concerned, said matching parameter each having a value thereof matching with that of a corresponding parameter included in the note information of the immediately preceding performance event information, and wherein the status information of said another form of performance event information is selected from a plurality of pieces of status information respectively provided in advance for a plurality of types of matching or mismatching patterns of a plurality of types of parameters included in the note information between performance event information and the immediately preceding performance event information.