Delay measurement apparatus and delay measurement method for network music session

A delay measurement method for network music session, the method being executed on a session terminal that performs a network music session with a partner session terminal connected with the session terminal through a communication network so that the session terminal communicates with the partner session terminal, the method comprising the steps of:

• a terminal's input delay retrieval step of retrieving terminal's input delay time from input of an audio signal to start of transmission of the audio signal on the terminal;
• a partner's output delay retrieval step of retrieving partner's output delay time from input of the audio signal from a reception buffer portion to output of the audio signal by an audio reproduction portion on the partner session terminal;
• a partner's reception buffering delay retrieval step of retrieving partner's reception buffering delay time from reception of the audio signal by the reception buffer portion of the partner session terminal to input of the audio signal to the audio reproduction portion of the partner session terminal;
• a transmission delay retrieval step of retrieving transmission delay time from the terminal to the partner terminal, the transmission delay time being taken from the start of transmission of the audio signal by the session terminal to reception of the audio signal by the partner session terminal;
• and
• an input/output delay time determination step of summing up the terminal's input delay time retrieved at the terminal's input delay retrieval step, the partner's output delay time retrieved at the partner's output delay retrieval step, the partner's reception buffering delay time retrieved at the partner's reception buffering delay retrieval step, and the transmission delay time from the terminal to the partner terminal retrieved at the transmission delay retrieval step, and determining input/output delay time from the input of the audio signal on the terminal to the output of the audio signal from the audio reproduction portion of the partner session terminal.

A computer-readable medium storing a delay measurement computer program for network music session, the computer program being executed on a session terminal that performs a network music session with a partner session terminal connected with the session terminal through a communication network so that the session terminal communicates with the partner session terminal, the computer program comprising the steps of:

• a terminal's input delay retrieval step of retrieving terminal's input delay time from input of an audio signal to start of transmission of the audio signal on the terminal;
• a partner's output delay retrieval step of retrieving partner's output delay time from input of the audio signal from a reception buffer portion to output of the audio signal by an audio reproduction portion on the partner session terminal;
• a partner's reception buffering delay retrieval step of retrieving partner's reception buffering delay time from reception of the audio signal by the reception buffer portion of the partner session terminal to input of the audio signal to the audio reproduction portion of the partner session terminal;
• a transmission delay retrieval step of retrieving transmission delay time from the terminal to the partner terminal, the transmission delay time being taken from the start of transmission of the audio signal by the session terminal to reception of the audio signal by the partner session terminal;
• and
• an input/output delay time determination step of summing up the terminal's input delay time retrieved at the terminal's input delay retrieval step, the partner's output delay time retrieved at the partner's output delay retrieval step, the partner's reception buffering delay time retrieved at the partner's reception buffering delay retrieval step, and the transmission delay time from the terminal to the partner terminal retrieved at the transmission delay retrieval step, and determining input/output delay time from the input of the audio signal on the terminal to the output of the audio signal from the audio reproduction portion of the partner session terminal.