Data modification method, data reproduction method, program, data modification device

A data modification method of controlling sound, the method comprising:

• detecting a plurality of beat positions from sound control data defining timing information of sounds recorded with a predetermined tempo;
• correcting the timing information based on a relationship between the plurality of beat positions and the predetermined tempo;
• and
• modifying the sound control data by adding correction information to a predetermined data section according to an amount of correction of the timing information in the predetermined data section.

A data modification method of controlling sound, the method comprising:

• providing a recording user interface that allows a user to instruct performance recording;
• recording sound control data defining timing information of a sound generation based on input performance information, after a start of the performance recording is instructed,
• providing a selection user interface that allows the user to select a modification mode to be applied to the recorded sound control data from among a plurality of modification modes including a first modification mode and a second modification mode, after a stop of the performance recording is instructed,
• modifying the sound control data based on the selected modification mode;
• and
• playing back performance sounds based on the modified sound control data.