Data reception and playback method, data receiving and playback apparatus, and data communication apparatus

A data reception and playback method comprising the steps of:

• recording a value on a counter comprised in a receiving apparatus upon reception of each of a plurality of packets, where each packet is assigned a time stamp in a transmitting apparatus and transmitted to said receiving apparatus;
• acquiring information on difference between a system clock of said transmitting apparatus and the system clock of said receiving apparatus based on the time stamp and the value on said counter;
• and
• correcting the value on said counter in accordance with the information on the difference between the system clocks.

A data receiving and playing apparatus comprising:

• a packet disassembler that disassembles a received packet and extracts a time stamp assigned on said packet;
• a read timing controller that determines a timing to read out said packet based on the extracted time stamp and the number of cycle times of a system clock;
• a variation time calculator that calculates a delay time variation between a plurality of packets that are received;
• a smoother that smoothes the delay time variation between said plurality of packets;
• and
• a smooth output monitor that monitors an output signal from said smoother and adjusts the system clock in accordance with said output signal.

A data receiving and playing apparatus comprising:

• a packet disassembler that disassembles a received packet to extract a time stamp assigned on said packet;
• a read timing controller that determines a timing to read out said packet based on the extracted time stamp and a value on a counter comprised in the apparatus;
• a variation time calculator that calculates a delay time variation between a plurality of packets that are received;
• a smoother that smoothes the delay time variation between said plurality of packets;
• and
• a smooth output monitor that monitors an output signal from said smoother and adjusts the system clock in accordance with said output signal.