---
url: >-
  https://adk.nht.io/api/@nhtio/adk/batteries/media/contracts/functions/pcmToBytes.md
---

# Function: pcmToBytes()

```ts
function pcmToBytes(pcm: Float32Array): Uint8Array;
```

Defined in: [src/batteries/media/contracts.ts:183](https://github.com/NHTIO/ADK/blob/v1.20260713.1/src/src/batteries/media/contracts.ts#L183)

Pack PCM samples into transport bytes for a [ConvertOutput](../interfaces/ConvertOutput.md).

## Parameters

| Parameter | Type           | Description                    |
| --------- | -------------- | ------------------------------ |
| `pcm`     | `Float32Array` | Mono PCM samples in `[-1, 1]`. |

## Returns

`Uint8Array`

The samples as little-endian Float32 bytes.

## Remarks

A `Float32Array` view over arbitrary `Uint8Array` bytes requires 4-byte alignment, which
sliced buffers do not guarantee — this helper (and [bytesToPcm](bytesToPcm.md)) copy-normalize so
neither side has to think about alignment.