# MP3 codec registration ## Description The MP3 audio codec (MPEG-1/2 Audio Layer III), specified in [ISO/IEC 13818-3](https://www.iso.org/standard/26797.html). ## Codec ID ```ts 'mp3' ``` ## `EncodedPacket` data The packet's data must be an MP3 frame as described in Section 2.4.2.2 of [ISO/IEC 13818-3](https://www.iso.org/standard/26797.html). ## `EncodedPacket` type The packet's type is always `'key'`. ## `AudioDecoderConfig` codec string ```ts 'mp3' ``` ## `AudioDecoderConfig` description `description` is not used for this codec.