Audio device which synchronizes audio data

An audio device which is configured to wirelessly receive audio data from another audio device, comprising:

• a memory which stores instructions, pulse data having a starting point and a predetermined length, and silent audio data,
• a clock which outputs an audio clock that indicates a timing of playback of the audio data, and
• a processor that is configured to execute the instructions stored in the memory to:
• wirelessly receive the audio data and a time stamp attached to the audio data from the other audio device,
• output the pulse data having the starting point and the predetermined length in the audio device, the pulse data being output when the audio device receives the audio data,
• detect start time of the pulse data based on the starting point by referring to the clock and end time of the pulse data by referring to the predetermined length and the start time,
• compare the end time of the pulse data and the time stamp,
• adjust the audio clock based on the comparing result, thereby adjusting the audio data,
• output the adjusted audio data synchronized with the other audio device and the adjusted audio clock, the adjusted audio data being output after the pulse data is output, and
• adjust a speed of the audio clock when there is a phase difference between the audio clock and the time stamp,
• wherein when the time stamp is later than the end time of the pulse data, the processor is configured to (i) output the silent audio data for a period corresponding to a difference between the time stamp and the end time of the pulse data, and (ii) output the audio data after the silent audio data is output.

A method for synchronizing audio data, the method being performed by an audio device which is configured to wirelessly receive the audio data from another audio device, the audio device comprising (i) a memory which stores instructions, pulse data having a starting point and a predetermined length, and silent audio data and (ii) a processor that is configured to execute the instructions stored in the memory, the method comprising:

• outputting an audio clock that indicates a timing of playback of the audio data, the step being performed by a clock,
• wirelessly receiving the audio data and a time stamp attached to the audio data from the other audio device, the step being performed by the processor,
• outputting the pulse data having the starting point and the predetermined length in the audio device, the pulse data being output when the audio device receives the audio data, the step being performed by the processor,
• detecting start time of the pulse data based on the starting point by referring to the clock and end time of the pulse data by referring to the predetermined length and the start time, the step being performed by the processor,
• comparing the end time of the pulse data and the time stamp, the step being performed by the processor,
• adjusting the audio clock based on the comparing result, thereby adjusting the audio data, the step being performed by the processor, and
• outputting the adjusted audio data synchronized with the other audio device, the adjusted audio data being output after the pulse data is output, the step being performed by the processor,
• wherein when the time stamp is later than the end time of the pulse data, the processor (i) outputs the silent audio data for a period corresponding to a difference between the time stamp and the end time of the pulse data, and (ii) outputs the audio data after the silent audio data is output.