Systems and methods for synchronizing operations among a plurality of independently clocked digital data processing devices without a voltage controlled crystal oscillator

摘要

Example systems, apparatus, and methods receive audio information including a plurality of frames from a source device, wherein each frame of the plurality of frames includes one or more audio samples and a time stamp indicating when to play the one or more audio samples of the respective frame. In an example, the time stamp is updated for each of the plurality of frames using a time differential value determined between clock information received from the source device and clock information associated with the device. The updated time stamp is stored for each of the plurality of frames, and the audio information is output based on the plurality of frames and associated updated time stamps. A number of samples per frame to be output is adjusted based on a comparison between the updated time stamp for the frame and a predicted time value for play back of the frame.

主权项

1. A digital data processing device included in a synchrony group of one or more digital data processing devices, the digital data processing device comprising:
an interface configured to receive multimedia information arranged as a plurality of frames, each frame to include one or more samples and an indication of when to play the one or more samples in a frame, the multimedia information to be played in synchrony with the synchrony group; an information buffer configured to store the plurality of frames for play back by the digital data processing device, wherein the digital data processing device is configured to receive clock information from a source device and determine a time differential value between the received clock information and clock information associated with the digital data processing device, the time differential value to be applied with the indication of when to play each of the plurality of frames to generate an updated indication of when to play each of the plurality of frames to be stored in the information buffer; and an output configured to play back one or more samples in a frame from the information buffer according to the updated indication of when to play the frame, wherein the digital data processing device is configured to adjust, independent of another device in the synchrony group and based on a comparison between the updated indication of when to play the frame and a predicted time value for play back of the frame, a number of samples per frame that are to be played.