  Neural audio codecs are initially introduced to compress audio data into
compact codes to reduce transmission latency. Researchers recently discovered
the potential of codecs as suitable tokenizers for converting continuous audio
into discrete codes, which can be employed to develop audio language models
(LMs). Numerous high-performance neural audio codecs and codec-based LMs have
been developed. The paper aims to provide a thorough and systematic overview of
the neural audio codec models and codec-based LMs.
