# Longcat Single Avatar · Audio to Video API

> Δημιουργεί βίντεο ομιλούντος άβαταρ που καθοδηγείται μόνο από αρχείο ήχου και prompt κειμένου, χωρίς εικόνα πηγής

Παράγει βίντεο άβαταρ με συγχρονισμό χειλιών από τα `audio_url` και `prompt` που περιγράφει το άτομο. Η έξοδος είναι 480p ή 720p. Το `num_segments` (1 έως 10) ορίζει τη διάρκεια: το πρώτο τμήμα είναι περίπου 5.8 δευτερόλεπτα και κάθε επόμενο προσθέτει 5 δευτερόλεπτα. Το `audio_guidance_scale` (1 έως 10) ελέγχει πόσο έντονα η ομιλία κινεί το στόμα, ενώ οι υψηλότερες τιμές μπορεί να υπερβάλλουν την κίνηση.

- Model id: `longcat-single-avatar/audio-to-video`
- Made by: Meituan
- Category: Lipsync & Avatars
- Output: video
- Price per second of your output video: from $0.15 / second of output video (cheapest run $0.15 (150 API credits))
- Run: `POST https://api.doitong.ru/v1/run/longcat-single-avatar/audio-to-video`
- Quote: `POST https://api.doitong.ru/v1/quote/longcat-single-avatar/audio-to-video`
- Docs page: https://doitong.com/el/developers/models/longcat-single-avatar/audio-to-video

## Pricing

Price: **from $0.15 / second of output video** (the lowest tier; the quote prices your exact input). Price per second of your output video: the input files are measured before the run (length, resolution, frame rate). The quote measures the same files and is exactly what the run charges.

Price by tier:

- base rate: $0.15 / second of output video
- 720p: $0.60 / second of output video

The full example input below costs $0.90 = 900 API credits (6 s output video × $0.15).

Prices are the upstream price in USD, paid from the API balance in API credits (1000 API credits = 1 USD). `POST https://api.doitong.ru/v1/quote/longcat-single-avatar/audio-to-video` with the same JSON body returns the exact price for that input; the quote is exactly what a run charges. Invalid input is never charged and failed or canceled requests are refunded automatically.

## Input parameters

Send either the canonical name or the native field name (not both). Canonical names are the same across models.

| Parameter | Canonical name | Type | Required | Default | Allowed values / range | Description |
|---|---|---|---|---|---|---|
| `audio_url` | `audio` | string (audio URL) | yes |  |  | URL αρχείου ήχου που χρησιμοποιείται για την καθοδήγηση του avatar. |
| `prompt` |  | string | no | `A person is talking naturally with natural expressions and movements.` |  | Prompt που καθοδηγεί την παραγωγή βίντεο. |
| `negative_prompt` |  | string | no | `Close-up, Bright tones, overexposed, static, blurred details, subtitles, style, works, paintings, images, static, overall gray, worst quality, low quality, JPEG compression residue, ugly, incomplete, extra fingers, poorly drawn hands, poorly drawn faces, deformed, disfigured, misshapen limbs, fused fingers, still picture, messy background, three legs, many people in the background, walking backwards` |  | Negative prompt που καθορίζει τι πρέπει να αποφεύγει η παραγωγή βίντεο. |
| `num_inference_steps` |  | integer | no | `50` | 10 – 100 | Πλήθος βημάτων inference που εκτελέστηκαν. |
| `text_guidance_scale` |  | number | no | `4` | 1 – 10 | Κλίμακα καθοδήγησης κειμένου που εφαρμόζεται στο classifier-free guidance. |
| `audio_guidance_scale` |  | number | no | `4` | 1 – 10 | Ρύθμιση καθοδήγησης ήχου που μπορεί να υπερτονίσει την κίνηση του στόματος όταν αυξάνεται. |
| `resolution` |  | enum (string) | no | `480p` | `480p`, `720p` | Ανάλυση βίντεο εξόδου, είτε 480p είτε 720p. |
| `num_segments` |  | integer | no | `1` | 1 – 10 | Πλήθος τμημάτων βίντεο, με περίπου 5.8s για το αρχικό τμήμα και 5s για κάθε επόμενο—περίπου 5 δευτερόλεπτα βίντεο ανά τμήμα. |
| `seed` |  | integer \| null | no |  |  | Τιμή seed που αρχικοποιεί την παραγωγή τυχαίων αριθμών. |
| `enable_safety_checker` |  | boolean | no | `true` |  | Εναλλαγή ελέγχου ασφάλειας που υπόκειται σε δικαιώματα λογαριασμού: οι έλεγχοι παραμένουν υποχρεωτικοί για μη εξουσιοδοτημένα αιτήματα και η απενεργοποίησή τους απαιτεί εξουσιοδότηση. |
| `enable_prompt_expansion` |  | boolean | no | `false` |  | Εναλλαγή επέκτασης prompt με βάση LLM για βελτίωση της ποιότητας βίντεο μέσω ενισχυμένου prompt. |

File parameters (`audio`) take a public `https://` URL, a `data:` URI up to 10 MB, or the `file_url` of an upload from `POST /files`.

## Example input

Required parameters only:

```json
{
  "audio": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
}
```

A fuller example:

```json
{
  "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
}
```

## Run it

Set `DOITONG_API_KEY` to a key from https://doitong.com/developers/dashboard#keys. `?wait=20` returns the finished request in the same call when it is ready within 20 seconds; otherwise poll `GET /requests/{id}` (it also accepts `?wait=`), or pass `webhook_url`.

### curl

```bash
# Run the model; wait up to 20 s for the finished result in the same call
curl -X POST "https://api.doitong.ru/v1/run/longcat-single-avatar/audio-to-video?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
  }'

# Still "queued" or "running"? Poll with the id from the response:
curl "https://api.doitong.ru/v1/requests/REQUEST_ID?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY"
```

### JavaScript

```javascript
const API = "https://api.doitong.ru/v1";
const headers = {
  "Authorization": "Bearer " + process.env.DOITONG_API_KEY,
  "Content-Type": "application/json",
};

// Run the model; wait up to 20 s for the finished result in the same call
let res = await fetch(API + "/run/longcat-single-avatar/audio-to-video?wait=20", {
  method: "POST",
  headers,
  body: JSON.stringify({
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
  }),
});
let request = await res.json();
if (!res.ok) throw new Error(request.error.code + ": " + request.error.message);

// Not finished yet: long-poll until it is
while (request.status === "queued" || request.status === "running") {
  res = await fetch(API + "/requests/" + request.id + "?wait=20", { headers });
  request = await res.json();
}
if (request.status !== "succeeded") throw new Error(JSON.stringify(request.error));
console.log(request.outputs.map((o) => o.url), request.cost.credits + " API credits ($" + request.cost.usd + ")");
```

### Python

```python
import os
import requests

API = "https://api.doitong.ru/v1"
headers = {"Authorization": "Bearer " + os.environ["DOITONG_API_KEY"]}

payload = {
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3",
}

# Run the model; wait up to 20 s for the finished result in the same call
r = requests.post(API + "/run/longcat-single-avatar/audio-to-video", params={"wait": 20}, json=payload, headers=headers)
request = r.json()
if not r.ok:
    raise RuntimeError(request["error"]["code"] + ": " + request["error"]["message"])

# Not finished yet: long-poll until it is
while request["status"] in ("queued", "running"):
    request = requests.get(API + "/requests/" + request["id"], params={"wait": 20}, headers=headers).json()
if request["status"] != "succeeded":
    raise RuntimeError(request["error"])
print([o["url"] for o in request["outputs"]], request["cost"]["credits"], "API credits", "$" + request["cost"]["usd"])
```

### MCP

The MCP server at `https://api.doitong.ru/v1/mcp` exposes the tools `search_models`, `get_model`, `quote`, `run`, `get_request`, `cancel_request`, `list_requests`, `create_upload` and `get_account`. A `run` call for this model:

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "run",
    "arguments": {
      "model_id": "longcat-single-avatar/audio-to-video",
      "input": {
        "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
      },
      "wait_seconds": 20
    }
  }
}
```

## Response

Every call returns a request object. `status` is one of `queued`, `running`, `succeeded`, `failed`, `canceled`. `outputs` lists the generated files with URLs on our storage (kept forever, or 7 days with `?storage=temporary`; `storage` says which); `output` is the model's own result object with the same URLs.

```json
{
  "id": "req_8k2m4q7x1z9c3v5b6n0p2r4t",
  "object": "request",
  "model": "longcat-single-avatar/audio-to-video",
  "status": "succeeded",
  "created_at": "2026-10-20T12:00:00Z",
  "started_at": "2026-10-20T12:00:02Z",
  "completed_at": "2026-10-20T12:00:09Z",
  "queue_position": null,
  "cost": {
    "credits": 900,
    "usd": "0.90",
    "charged": 900,
    "refunded": 0
  },
  "input": {
    "audio_url": "https://content.doitong.com/audio/showcase/v3/tools/dub_es.mp3"
  },
  "output": {
    "video": {
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.mp4",
      "content_type": "video/mp4",
      "file_name": "0-output.mp4",
      "file_size": 1843200
    },
    "seed": 42
  },
  "outputs": [
    {
      "type": "video",
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.mp4",
      "content_type": "video/mp4",
      "file_size": 1843200,
      "width": 1280,
      "height": 720,
      "duration": 5,
      "stored": true
    }
  ],
  "error": null,
  "metrics": {
    "inference_seconds": 6.8
  },
  "urls": {
    "self": "https://api.doitong.ru/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t",
    "cancel": "https://api.doitong.ru/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t/cancel"
  }
}
```

### Output fields (`output`)

| Field | Type | Description |
|---|---|---|
| `video` | object {url, content_type, file_name, file_size} | Αρχείο βίντεο που παράγεται από την παραγωγή. |
| `seed` | integer | Τιμή seed που εφαρμόζεται κατά την παραγωγή. |

## Related models

- [Longcat Single Avatar · Image Audio to Video](https://doitong.com/developers/models/longcat-single-avatar/image-audio-to-video.md) (`longcat-single-avatar/image-audio-to-video`): from $0.15 / second of output video
- [Kling AI Avatar 2.0 Pro](https://doitong.com/developers/models/kling-video/ai-avatar/v2/pro.md) (`kling-video/ai-avatar/v2/pro`): $0.115 / second of input audio
- [Sync Lipsync 3](https://doitong.com/developers/models/sync-lipsync/v3.md) (`sync-lipsync/v3`): $8.00 / minute of output video
- [VEED Fabric 1.0](https://doitong.com/developers/models/veed/fabric-1.0.md) (`veed/fabric-1.0`): from $0.08 / second of input audio
- [Infinitalk](https://doitong.com/developers/models/infinitalk.md) (`infinitalk`): from $0.20 / second of output video
- [Infinitalk · Single Text](https://doitong.com/developers/models/infinitalk/single-text.md) (`infinitalk/single-text`): from $2.32 / run
- [Infinitalk · Video to Video](https://doitong.com/developers/models/infinitalk/video-to-video.md) (`infinitalk/video-to-video`): from $0.30 / second of output video
- [AI Avatar Multi](https://doitong.com/developers/models/ai-avatar/multi.md) (`ai-avatar/multi`): from $0.20 / second of output video

## Links

- HTML page: https://doitong.com/developers/models/longcat-single-avatar/audio-to-video
- All models and guides for AI agents: https://doitong.com/developers/llms.txt
- OpenAPI 3.1 with this model's typed request body: https://doitong.com/developers/openapi.json?model=longcat-single-avatar/audio-to-video
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.ru/v1/models/longcat-single-avatar/audio-to-video