Methods and systems for avb networks

A communication system comprising:

• a talker device including:
• a transmission buffer for storing audio/video data blocks for transmission, and
• a presentation time module including first instructions executable by a processor of the talker device to determine which of a plurality of data blocks in an audio/video stream are to be time stamped with a valid presentation time in an associated timestamp validation field;
• and
• a listener device communicatively connected to the talker device and configured to receive the audio/video stream from the talker device, the listener device comprising presentation time validation module including second instructions executable by a processor of the listener device to:
• evaluate a timestamp validation field for each packet of the audio/video stream to determine whether that packet includes a data block with a valid presentation time, and
• present the audio/video stream in accordance with each determined valid presentation time.

A method for determining which packets of an audio/video stream transmitted from a talker device to a listener device include a valid presentation time, the method comprising:

• acquiring a sample of the audio/video stream;
• determining a number of data blocks in the sample;
• performing a modulus operation of the total number of data blocks and an syt_interval value to determine a number of data blocks that have been sampled since a last valid presentation time stamped data block, the syt_interval value defining a number of data blocks between two successive valid presentation times in the audio/video stream;
• determining a sum of the number of data blocks that have been sampled since the last valid presentation time stamped data block and the number of data blocks in the sample;
• encapsulating the sample in a packet;
• and
• setting a timestamp_valid field of a header of the packet to a selected value designating the packet as including a valid presentation time responsive to determining that the number of data blocks that have been sampled since the last valid presentation time stamped data block is greater than or equal to the syt_interval value.