---
title: LTX-2 Retake | Runware Docs
url: https://runware.ai/docs/models/lightricks-ltx-2-retake
description: Segmented AI video retakes with precise in-shot control
---
# LTX-2 Retake

LTX-2 Retake regenerates targeted segments inside an existing clip. Define start time and duration. Replace video, audio or both with new prompts. Preserve surrounding motion and continuity. Ideal for selective revisions, dialog tweaks, and shot refinements without full regen.

- **ID**: `lightricks:3@1`
- **Status**: live
- **Creator**: Lightricks
- **Release Date**: November 28, 2025
- **Capabilities**: Video to Video, Audio to Audio

## Pricing

- **1s**: `$0.10`

## Request Parameters

**API Options**

Platform-level options for task execution and delivery.

### [taskType](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-tasktype)

- **Type**: `string`
- **Required**: true
- **Value**: `videoInference`

Identifier for the type of task being performed

### [taskUUID](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-taskuuid)

- **Type**: `string`
- **Required**: true
- **Format**: `UUID v4`

UUID v4 identifier for tracking tasks and matching async responses. Must be unique per task.

### [outputType](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-outputtype)

- **Type**: `string`
- **Default**: `URL`

Video output type.

**Allowed values**: `URL`

### [outputFormat](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-outputformat)

- **Type**: `string`
- **Default**: `MP4`

Specifies the file format of the generated output. The available values depend on the task type and the specific model's capabilities.

- \`MP4\`: Widely supported video container (H.264), recommended for general use.
- \`WEBM\`: Optimized for web delivery.
- \`MOV\`: QuickTime format, common in professional workflows (Apple ecosystem).

**Allowed values**: `MP4` `WEBM` `MOV`

### [outputQuality](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-outputquality)

- **Type**: `integer`
- **Min**: `20`
- **Max**: `99`
- **Default**: `95`

Compression quality of the output. Higher values preserve quality but increase file size.

### [webhookURL](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-webhookurl)

- **Type**: `string`
- **Format**: `URI`

Specifies a webhook URL where JSON responses will be sent via HTTP POST when generation tasks complete. For batch requests with multiple results, each completed item triggers a separate webhook call as it becomes available.

**Learn more** (1 resource):

- [Webhooks](https://runware.ai/docs/platform/webhooks) (platform)

### [deliveryMethod](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-deliverymethod)

- **Type**: `string`
- **Default**: `async`

Determines how the API delivers task results.

**Allowed values**:

- `async` Returns an immediate acknowledgment with the task UUID. Poll for results using getResponse. Required for long-running tasks like video generation.

**Learn more** (1 resource):

- [Task Polling](https://runware.ai/docs/platform/task-polling) (platform)

### [uploadEndpoint](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-uploadendpoint)

- **Type**: `string`
- **Format**: `URI`

Specifies a URL where the generated content will be automatically uploaded using the HTTP PUT method. The raw binary data of the media file is sent directly as the request body. For secure uploads to cloud storage, use presigned URLs that include temporary authentication credentials.

**Common use cases:**

- **Cloud storage**: Upload directly to S3 buckets, Google Cloud Storage, or Azure Blob Storage using presigned URLs.
- **CDN integration**: Upload to content delivery networks for immediate distribution.

```text
// S3 presigned URL for secure upload
https://your-bucket.s3.amazonaws.com/generated/content.mp4?X-Amz-Signature=abc123&X-Amz-Expires=3600

// Google Cloud Storage presigned URL
https://storage.googleapis.com/your-bucket/content.jpg?X-Goog-Signature=xyz789

// Custom storage endpoint
https://storage.example.com/uploads/generated-image.jpg
```

The content data will be sent as the request body to the specified URL when generation is complete.

### [safety](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-safety)

- **Path**: `safety.checkContent`
- **Type**: `object (2 properties)`

Content safety checking configuration for video generation.

#### [checkContent](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-safety-checkcontent)

- **Path**: `safety.checkContent`
- **Type**: `boolean`
- **Default**: `false`

Enable or disable content safety checking. When enabled, defaults to `fast` mode.

#### [mode](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-safety-mode)

- **Path**: `safety.mode`
- **Type**: `string`
- **Default**: `none`

Safety checking mode for video generation.

**Allowed values**:

- `none` Disables checking.
- `fast` Checks key frames.
- `full` Checks all frames.

### [ttl](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-ttl)

- **Type**: `integer`
- **Min**: `60`

Time-to-live (TTL) in seconds for generated content. Only applies when `outputType` is `URL`.

### [includeCost](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-includecost)

- **Type**: `boolean`
- **Default**: `false`

Include task cost in the response.

### [numberResults](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-numberresults)

- **Type**: `integer`
- **Min**: `1`
- **Max**: `4`
- **Default**: `1`

Number of results to generate. Each result uses a different seed, producing variations of the same parameters.

**Inputs**

Input resources for the task (images, audio, etc). These must be nested inside the \`inputs\` object.

### [frameImages](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-inputs-frameimages)

- **Path**: `inputs.frameImages`
- **Type**: `array of strings or objects`

An array of frame-specific image inputs to guide video generation. Each item can be either a plain image input (UUID, URL, Data URI, or Base64) or an object that pairs an image with a target frame position.

The `frameImages` parameter allows you to constrain specific frames within the video sequence, ensuring that particular visual content appears at designated points. This is different from `referenceImages`, which provide overall visual guidance without constraining specific timeline positions.

When the `frame` parameter is omitted, automatic distribution rules apply:

- **1 image**: Used as the first frame.

**Examples**:

**Shorthand format:** When you don't need to specify a frame position, you can pass a plain image input directly.

```json
"frameImages": [
  "aac49721-1964-481a-ae78-8a4e29b91402"
]
```

**Object format:** When you need to specify a frame position, use an object with `image` and `frame`.

```json
"frameImages": [
  {
    "image": "aac49721-1964-481a-ae78-8a4e29b91402",
    "frame": "first"
  }
]
```

**Format 1: string[]**:

- **Type**: `string`

Image input (UUID, URL, Data URI, or Base64).

**Format 2: object[]**:

#### [image](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-inputs-frameimages-format-2-image)

- **Path**: `inputs.frameImages.image`
- **Type**: `string`
- **Required**: true

Image input (UUID, URL, Data URI, or Base64).

#### [frame](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-inputs-frameimages-format-2-frame)

- **Path**: `inputs.frameImages.frame`
- **Type**: `object`

Target frame position for the image. This model only supports the first frame.

**Allowed values**:

- `first` First frame of the video.
- `0` Frame index 0 (first frame).

### [video](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-inputs-video)

- **Path**: `inputs.video`
- **Type**: `string`
- **Required**: true

Video input (UUID or URL).

**Generation Parameters**

Core parameters for controlling the generated content.

### [model](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-model)

- **Type**: `string`
- **Required**: true
- **Value**: `lightricks:3@1`

Identifier of the model to use for generation.

**Learn more** (3 resources):

- [Text To Image: Model Selection The Foundation Of Generation](https://runware.ai/docs/guides/text-to-image#model-selection-the-foundation-of-generation) (guide)
- [Image Inpainting: Model Specialized Inpainting Models](https://runware.ai/docs/guides/image-inpainting#model-specialized-inpainting-models) (guide)
- [Image Outpainting: Other Critical Parameters](https://runware.ai/docs/guides/image-outpainting#other-critical-parameters) (guide)

### [positivePrompt](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-positiveprompt)

- **Type**: `string`
- **Min**: `1`
- **Max**: `5000`

Text prompt describing elements to include in the generated output.

**Learn more** (2 resources):

- [Text To Image: Prompts Guiding The Generation](https://runware.ai/docs/guides/text-to-image#prompts-guiding-the-generation) (guide)
- [Image Outpainting: Other Critical Parameters](https://runware.ai/docs/guides/image-outpainting#other-critical-parameters) (guide)

**Provider Settings**

Parameters specific to this model provider. These must be nested inside the \`providerSettings.lightricks\` object.

### [duration](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-providersettings-lightricks-duration)

- **Path**: `providerSettings.lightricks.duration`
- **Type**: `integer`
- **Min**: `1`

Duration in seconds to regenerate. Combined with `startTime` must not exceed input video length.

### [mode](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-providersettings-lightricks-mode)

- **Path**: `providerSettings.lightricks.mode`
- **Type**: `string`
- **Default**: `replace_audio_and_video`

Track replacement mode for the edited segment.

**Allowed values**:

- `replace_audio` Regenerate only the audio track, preserving original video.
- `replace_video` Regenerate only the video track, preserving original audio.
- `replace_audio_and_video` Regenerate both audio and video tracks.

### [startTime](https://runware.ai/docs/models/lightricks-ltx-2-retake#request-providersettings-lightricks-starttime)

- **Path**: `providerSettings.lightricks.startTime`
- **Type**: `integer`
- **Min**: `0`

Start time in seconds for the regenerated segment. Must be within input video duration.

## Response Parameters

### [taskType](https://runware.ai/docs/models/lightricks-ltx-2-retake#response-tasktype)

- **Type**: `string`
- **Required**: true
- **Value**: `videoInference`

Type of the task.

### [taskUUID](https://runware.ai/docs/models/lightricks-ltx-2-retake#response-taskuuid)

- **Type**: `string`
- **Required**: true
- **Format**: `UUID v4`

UUID of the task.

### [videoUUID](https://runware.ai/docs/models/lightricks-ltx-2-retake#response-videouuid)

- **Type**: `string`
- **Required**: true
- **Format**: `UUID v4`

UUID of the output video.

### [videoURL](https://runware.ai/docs/models/lightricks-ltx-2-retake#response-videourl)

- **Type**: `string`
- **Format**: `URI`

URL of the output video.

### [videoBase64Data](https://runware.ai/docs/models/lightricks-ltx-2-retake#response-videobase64data)

- **Type**: `string`

Base64-encoded video data.

### [videoDataURI](https://runware.ai/docs/models/lightricks-ltx-2-retake#response-videodatauri)

- **Type**: `string`
- **Format**: `URI`

Data URI of the output video.

### [seed](https://runware.ai/docs/models/lightricks-ltx-2-retake#response-seed)

- **Type**: `integer`

The seed used for generation. If none was provided, shows the randomly generated seed.

### [NSFWContent](https://runware.ai/docs/models/lightricks-ltx-2-retake#response-nsfwcontent)

- **Type**: `boolean`

Flag indicating if NSFW content was detected.

### [cost](https://runware.ai/docs/models/lightricks-ltx-2-retake#response-cost)

- **Type**: `float`

Task cost in USD. Present when `includeCost` is set to `true` in the request.

## Examples

### Windblown Salt Flats Chase (Video to Video)

[Watch video](https://assets.runware.ai/examples/lightricks-ltx-2-retake/4f14ddfb-60c1-4666-ae1e-10816c99e405.mp4)

**Request**:

```json
{
  "taskType": "videoInference",
  "taskUUID": "2eb310fd-c023-46a5-a0fa-5e977ff54bce",
  "model": "lightricks:3@1",
  "positivePrompt": "Replace the selected segment with a more dramatic continuation of the salt-flat motorcycle chase: one rider cuts sharply across the other leaving a sweeping ribbon of dust, the camera drops lower near the ground for a fast tracking angle, tires scatter crystalline grit, distant mountains shimmer in the heat haze, naturalistic cinematic motion, realistic sunlight, seamless match to the surrounding footage. Regenerate both sound and picture with roaring engines, skidding grit, rushing wind, and a brief tense near-collision feeling.",
  "providerSettings": {
    "lightricks": {
      "startTime": 2,
      "duration": 3,
      "mode": "replace_audio_and_video"
    }
  },
  "inputs": {
    "video": "https://assets.runware.ai/assets/inputs/dfaf49f6-a1d2-4f75-b705-7f9fc11614ef.mp4"
  }
}
```

**Response**:

```json
{
  "taskType": "videoInference",
  "taskUUID": "2eb310fd-c023-46a5-a0fa-5e977ff54bce",
  "videoUUID": "eb3d2591-8f26-4c24-9b6b-cb72d1f8d84c",
  "videoURL": "https://vm.runware.ai/video/os/a04d20/ws/5/vi/eb3d2591-8f26-4c24-9b6b-cb72d1f8d84c.mp4",
  "cost": 0.605
}
```

---

### Hailstorm Rooftop Violin Solo (Video to Video)

[Watch video](https://assets.runware.ai/examples/lightricks-ltx-2-retake/775f9bb1-e2e0-4027-b48f-5deffab07ed3.mp4)

**Request**:

```json
{
  "taskType": "videoInference",
  "taskUUID": "fd711854-7776-4ba6-aabc-45346fc7ec37",
  "model": "lightricks:3@1",
  "positivePrompt": "Retake only the selected segment so the rooftop performance suddenly shifts into a violent hailstorm. Keep the same violinist, wardrobe, camera angle, framing, rooftop layout, skyline placement, and motion continuity from the surrounding clip. Dark gust clouds roll in fast, loose sheets snap on a clothesline, hailstones ricochet across puddles and concrete, the musician braces against the wind while continuing to play with intense concentration. Cinematic realism, wet surfaces, sharp atmospheric detail, natural motion blur, believable continuity at the edit boundaries. Replace audio and video with fierce wind, rattling hail impacts, fluttering fabric, distant thunder, and a more forceful, urgent violin phrase that matches the performer’s movements.",
  "providerSettings": {
    "lightricks": {
      "startTime": 2,
      "duration": 3,
      "mode": "replace_audio_and_video"
    }
  },
  "inputs": {
    "video": "https://assets.runware.ai/assets/inputs/a5fa4c72-d8d2-48e7-bbe7-69107238ef47.mp4"
  }
}
```

**Response**:

```json
{
  "taskType": "videoInference",
  "taskUUID": "fd711854-7776-4ba6-aabc-45346fc7ec37",
  "videoUUID": "cb6f3ad7-5c1d-436c-8bf7-5a05ba1284cc",
  "videoURL": "https://vm.runware.ai/video/os/a15d18/ws/5/vi/cb6f3ad7-5c1d-436c-8bf7-5a05ba1284cc.mp4",
  "cost": 0.605
}
```

---

### Fogbound Viaduct Train Crossing (Video to Video)

[Watch video](https://assets.runware.ai/examples/lightricks-ltx-2-retake/042fee44-c60c-4008-9b5b-fe4b496f3831.mp4)

**Request**:

```json
{
  "taskType": "videoInference",
  "taskUUID": "b049395b-2798-47d4-a238-06ada89c143b",
  "model": "lightricks:3@1",
  "positivePrompt": "For the selected segment, transform the outside view into a surreal yet believable encounter: a giant manta-shaped wind craft made of ribbed canvas and polished brass glides alongside the train at close distance, its wings flexing in the mist, droplets trailing from the frame, soft amber guide lamps glowing under its body, swirling fog displaced by its passage, realistic motion parallax from the train window, cinematic atmosphere, seamless continuity with the original shot, matching camera angle and movement; regenerate sound to include deep fabric creaks, gusting air, resonant cable hum, and a brief hush from awestruck passengers while keeping the train ambience coherent.",
  "providerSettings": {
    "lightricks": {
      "startTime": 2,
      "duration": 3,
      "mode": "replace_audio_and_video"
    }
  },
  "inputs": {
    "video": "https://assets.runware.ai/assets/inputs/a3978086-ee43-4a4a-b9ee-f4462cfdd7d0.mp4"
  }
}
```

**Response**:

```json
{
  "taskType": "videoInference",
  "taskUUID": "b049395b-2798-47d4-a238-06ada89c143b",
  "videoUUID": "aa18d70a-418e-4789-8870-a160df40c151",
  "videoURL": "https://vm.runware.ai/video/os/a05d22/ws/5/vi/aa18d70a-418e-4789-8870-a160df40c151.mp4",
  "cost": 0.605
}
```

---

### Subterranean Crystal Tram Arrival (Video to Video)

[Watch video](https://assets.runware.ai/examples/lightricks-ltx-2-retake/bf13a80c-8467-4008-8414-29d6f55ad389.mp4)

**Request**:

```json
{
  "taskType": "videoInference",
  "taskUUID": "1cf591e2-05cd-46b6-988d-4b3b8daacdcf",
  "model": "lightricks:3@1",
  "positivePrompt": "Transform the selected segment into a majestic underground transit stop carved through towering quartz and copper-veined stone, with a sleek glass-sided tram gliding in on polished tracks. Shimmering crystals embedded in the cavern walls cast soft prismatic highlights across the platform. A few travelers in weathered expedition coats wait calmly with satchels and instrument cases. Fine dust motes drift in the air, subtle reflections ripple across the tram windows, and the arrival soundscape becomes a resonant metallic hum with echoing rail friction and distant cavern ambience. Keep camera movement, timing, and scene continuity natural with the surrounding clip.",
  "providerSettings": {
    "lightricks": {
      "startTime": 2,
      "duration": 3,
      "mode": "replace_audio_and_video"
    }
  },
  "inputs": {
    "video": "https://assets.runware.ai/assets/inputs/8645e38e-d263-4976-a5a0-344f1da81cab.mp4"
  }
}
```

**Response**:

```json
{
  "taskType": "videoInference",
  "taskUUID": "1cf591e2-05cd-46b6-988d-4b3b8daacdcf",
  "videoUUID": "94936a61-18fa-4f13-8826-254f811ca441",
  "videoURL": "https://vm.runware.ai/video/os/a12d13/ws/5/vi/94936a61-18fa-4f13-8826-254f811ca441.mp4",
  "cost": 0.605
}
```