---
description: A-law companded PCM audio codec definition, defining legal codec strings, decoder configs, and packet data formats.
---
# A-law PCM codec registration
## Description
The A-law companded PCM audio codec, specified in [ITU-T G.711](https://www.itu.int/rec/T-REC-G.711) Tables 1a and 1b.
## Codec ID
```ts
'alaw'
```
## `EncodedPacket` data
The packet's data must be a sequence of bytes of arbitrary length (divisible by the channel count), where each byte is an A-law encoded PCM sample. For multichannel audio, samples from different channels are interleaved.
## `EncodedPacket` type
The packet's type is always `'key'`.
## `AudioDecoderConfig` codec string
```ts
'alaw'
```
## `AudioDecoderConfig` description
`description` is not used for this codec.