> ## Documentation Index
> Fetch the complete documentation index at: https://comfytv.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Demux · Audio Track

> **Extract the audio stream** from a video container as `COMFYTV_AUDIO`. **PyAV** — pairs with **Demux · Silent Video**.

<Frame caption="Demux · Audio Track · screenshot coming soon">
  <img src="https://mintcdn.com/comfytv/dMkMxJDZdIo4YzAU/images/nodes/_placeholder.svg?fit=max&auto=format&n=dMkMxJDZdIo4YzAU&q=85&s=b54171099e5b02d4313fe581171ebbcc" alt="Demux · Audio Track" width="800" height="450" data-path="images/nodes/_placeholder.svg" />
</Frame>

## What this node does

**Demux · Audio Track** reads audio from `COMFYTV_VIDEO` and writes a standalone audio file (`/view?` URL). For picture-only, use **Demux · Silent Video**.

Toolbar 🔀 **Demux** on upstream video stages creates **both** Audio Track + Silent Video nodes wired automatically.

## When to use it

* Pull BGM / dialogue for **Audio Stage** or IA2V
* Feed **Vocals Only** (Demucs — ⏳ pending)
* Replace audio: Silent Video + new audio (ffmpeg / future Timeline)

## How it works

* **Stage** + **▶ Run**; PyAV `demux_audio`, no GPU.
* **Snapshot**: audio URL persisted in project.
* Shares source video snapshot with Silent Video; separate Run outputs.

## Types

| ComfyTV type    | What it is            | vs ComfyUI       |
| --------------- | --------------------- | ---------------- |
| `COMFYTV_VIDEO` | Input video snapshot  | Not `VIDEO`      |
| `COMFYTV_AUDIO` | Output audio snapshot | Not `AUDIO` dict |

[bridges.md](https://github.com/jtydhr88/ComfyTV/blob/main/docs/bridges.md)

## Parameters

### video

Source `COMFYTV_VIDEO`. Required.

## Outputs

| Output    | Type            | Downstream                                                   |
| --------- | --------------- | ------------------------------------------------------------ |
| **audio** | `COMFYTV_AUDIO` | **Video Stage** (IA2V), **Audio Stage**, **← ComfyTV Audio** |

## Step by step

1. Run upstream **Video Stage** or **Load Video**.
2. Add **Demux · Audio Track** or click 🔀 **Demux** on upstream toolbar.
3. **▶ Run**.
4. Wire **audio** to **Video Stage** **audio** (IA2V) or **Vocals Only** (pending).

## Full guides (recommended reading)

> This page covers **one node only**. For end-to-end workflows, multi-stage pipelines, type conversion, and design rationale, see the [ComfyTV user guides](https://github.com/jtydhr88/ComfyTV/tree/main/docs) on GitHub:

| Guide                                                                                    | Contents                                                                |
| ---------------------------------------------------------------------------------------- | ----------------------------------------------------------------------- |
| [Getting started](https://github.com/jtydhr88/ComfyTV/blob/main/docs/getting-started.md) | Install, canvas basics, per-stage Run, snapshots, Project, Image Picker |
| [Video and audio](https://github.com/jtydhr88/ComfyTV/blob/main/docs/video-and-audio.md) | Clip, crop, resize, extract frame, demux vs Generate video              |

## Repository and workflows

| Resource               | Link                                                                                                                                             |
| ---------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------ |
| **GitHub repository**  | [https://github.com/jtydhr88/ComfyTV](https://github.com/jtydhr88/ComfyTV)                                                                       |
| **User guides index**  | [https://github.com/jtydhr88/ComfyTV/tree/main/docs](https://github.com/jtydhr88/ComfyTV/tree/main/docs)                                         |
| **Built-in workflows** | [https://github.com/jtydhr88/ComfyTV/tree/main/workflows](https://github.com/jtydhr88/ComfyTV/tree/main/workflows)                               |
| **Model checklist**    | [https://github.com/jtydhr88/ComfyTV/blob/main/docs/models.md](https://github.com/jtydhr88/ComfyTV/blob/main/docs/models.md)                     |
| **Custom workflows**   | [https://github.com/jtydhr88/ComfyTV/blob/main/docs/custom-workflows.md](https://github.com/jtydhr88/ComfyTV/blob/main/docs/custom-workflows.md) |

## FAQ

**Q: No audio stream?**\
A: Source may be silent; PyAV may error or write empty output.

**Q: Where is Demux button?**\
A: 🔀 **Demux** on upstream video stage toolbar.

**Q: Native AUDIO?**\
A: Add **← ComfyTV Audio**.

## Related nodes

* **Demux · Silent Video**
* **Vocals Only** / **Background Only** (pending)
* **Video Stage** (IA2V)