Methods and apparatus to perform audio watermarking and watermark detection and extraction

A non-transitory computer readable medium comprising instructions to cause a machine to at least:

• detect a first symbol, a second symbol, a third symbol, and a fourth symbol sequentially in encoded audio samples;
• determine whether the first symbol is a synchronization symbol;
• in response to a determination that the first symbol is a synchronization symbol, determine that the first symbol and the third symbol are associated with a first message and the second symbol and the fourth symbol are associated with a second message;
• and
• output at least one of the first message or the second message in response to a determination that a number of audio samples between the first message and the second message corresponds to an encoding repetition rate.

A method to transform media content into a message, the method comprising:

• detecting a first symbol, a second symbol, a third symbol, and a fourth symbol sequentially in encoded audio samples;
• determining whether the first symbol is a synchronization symbol;
• in response to a determination that the first symbol is a synchronization symbol, determining that the first symbol and the third symbol are associated with a first message and the second symbol and the fourth symbol are associated with a second message;
• and
• outputting at least one of the first message or the second message in response to a determination that a number of audio samples between the first message and the second message corresponds to an encoding repetition rate.