---
title: Riverflow 2 Preview Fast | Runware Docs
url: https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast
description: Fast lightweight Riverflow 2 for product accurate images
---
# Riverflow 2 Preview Fast

Riverflow 2 Preview Fast is a lightweight edition tuned for speed and lower cost. It supports text-to-image generation for product visuals with strong brand accuracy. It also handles precise image editing so teams can refine packaging and marketing assets efficiently.

- **ID**: `sourceful:2@2`
- **Status**: live
- **Creator**: Sourceful
- **Release Date**: November 19, 2025
- **Capabilities**: Text to Image, Image to Image, Image Editing, Upscale

## Pricing

Each image generation costs $0.02525 at 1024x1024.

- **1024x1024**: `$0.02525`

## Compatibility & Validation

`width` and `height` must be used together.

---

The following dimension combinations are supported:

| Configuration | Dimensions |
| --- | --- |
| `1K (1:1)` | `1024x1024` |
| `2K (1:1)` | `2048x2048` |
| `4K (1:1)` | `4096x4096` |
| `1K (4:3)` | `1152x864` |
| `2K (4:3)` | `2304x1728` |
| `4K (4:3)` | `4608x3456` |
| `1K (3:4)` | `864x1152` |
| `2K (3:4)` | `1728x2304` |
| `4K (3:4)` | `3456x4608` |
| `1K (16:9)` | `1280x720` |
| `2K (16:9)` | `2560x1440` |
| `4K (16:9)` | `5120x2880` |
| `1K (9:16)` | `720x1280` |
| `2K (9:16)` | `1440x2560` |
| `4K (9:16)` | `2880x5120` |
| `1K (3:2)` | `1248x832` |
| `2K (3:2)` | `2496x1664` |
| `4K (3:2)` | `4992x3328` |
| `1K (2:3)` | `832x1248` |
| `2K (2:3)` | `1664x2496` |
| `4K (2:3)` | `3328x4992` |
| `1K (7:3)` | `1512x648` |
| `2K (7:3)` | `3024x1296` |
| `4K (7:3)` | `6048x2592` |

## Request Parameters

**API Options**

Platform-level options for task execution and delivery.

### [taskType](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#request-tasktype)

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

Identifier for the type of task being performed

### [taskUUID](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#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/sourceful-riverflow-2-preview-fast#request-outputtype)

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

Image output type.

**Allowed values**: `URL` `base64Data` `dataURI`

### [outputFormat](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#request-outputformat)

- **Type**: `string`
- **Default**: `JPG`

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

- \`JPG\`: Best for photorealistic images with smaller file sizes (no transparency).
- \`PNG\`: Lossless compression, supports high quality and transparency (alpha channel).
- \`WEBP\`: Modern format providing superior compression and transparency support.

> [!NOTE]
> \*\*Transparency\*\*: If you are using features like background removal or LayerDiffuse that require transparency, you must select a format that supports an alpha channel (e.g., \`PNG\`, \`WEBP\`, \`TIFF\`). \`JPG\` does not support transparency.

**Allowed values**: `JPG` `PNG` `WEBP`

### [outputQuality](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#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/sourceful-riverflow-2-preview-fast#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/sourceful-riverflow-2-preview-fast#request-deliverymethod)

- **Type**: `string`
- **Default**: `sync`

Determines how the API delivers task results.

**Allowed values**:

- `sync` Returns complete results directly in the API response.
- `async` Returns an immediate acknowledgment with the task UUID. Poll for results using getResponse.

**Learn more** (1 resource):

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

### [uploadEndpoint](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#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/sourceful-riverflow-2-preview-fast#request-safety)

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

Content safety checking configuration for image generation.

#### [checkContent](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#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/sourceful-riverflow-2-preview-fast#request-safety-mode)

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

Safety checking mode for image generation.

**Allowed values**:

- `none` Disables checking.
- `fast` Performs a single check.

### [ttl](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#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/sourceful-riverflow-2-preview-fast#request-includecost)

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

Include task cost in the response.

### [numberResults](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#request-numberresults)

- **Type**: `integer`
- **Min**: `1`
- **Max**: `20`
- **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.

### [referenceImages](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#request-inputs-referenceimages)

- **Path**: `inputs.referenceImages`
- **Type**: `array of strings`

List of reference images (UUID, URL, Data URI, or Base64).

**Generation Parameters**

Core parameters for controlling the generated content.

### [model](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#request-model)

- **Type**: `string`
- **Required**: true
- **Value**: `sourceful:2@2`

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/sourceful-riverflow-2-preview-fast#request-positiveprompt)

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

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)

### [width](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#request-width)

- **Type**: `integer`
- **Required**: true
- **Paired with**: height

Width of the generated media in pixels.

**Learn more** (2 resources):

- [Image To Image: Dimensions Changing Aspect Ratio](https://runware.ai/docs/guides/image-to-image#dimensions-changing-aspect-ratio) (guide)
- [Image Outpainting: Dimensions Critical For Outpainting](https://runware.ai/docs/guides/image-outpainting#dimensions-critical-for-outpainting) (guide)

### [height](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#request-height)

- **Type**: `integer`
- **Required**: true
- **Paired with**: width

Height of the generated media in pixels.

**Learn more** (2 resources):

- [Image To Image: Dimensions Changing Aspect Ratio](https://runware.ai/docs/guides/image-to-image#dimensions-changing-aspect-ratio) (guide)
- [Image Outpainting: Dimensions Critical For Outpainting](https://runware.ai/docs/guides/image-outpainting#dimensions-critical-for-outpainting) (guide)

## Response Parameters

### [taskType](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#response-tasktype)

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

Type of the task.

### [taskUUID](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#response-taskuuid)

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

UUID of the task.

### [imageUUID](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#response-imageuuid)

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

UUID of the output image.

### [imageURL](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#response-imageurl)

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

URL of the output image.

### [imageBase64Data](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#response-imagebase64data)

- **Type**: `string`

Base64-encoded image data.

### [imageDataURI](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#response-imagedatauri)

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

Data URI of the output image.

### [seed](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#response-seed)

- **Type**: `integer`

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

### [NSFWContent](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#response-nsfwcontent)

- **Type**: `boolean`

Flag indicating if NSFW content was detected.

### [cost](https://runware.ai/docs/models/sourceful-riverflow-2-preview-fast#response-cost)

- **Type**: `float`

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

## Examples

### Heritage Spice Tin Collection (Image to Image)

![Heritage Spice Tin Collection](https://assets.runware.ai/examples/sourceful-riverflow-2-preview-fast/ad2ad0b3-fea8-4ce0-9b31-70164293add0.jpg)

**Request**:

```json
{
  "taskType": "imageInference",
  "taskUUID": "cb03d500-1eeb-4809-89b4-20a5bf86f8ca",
  "model": "sourceful:2@2",
  "positivePrompt": "Create a premium packaged product hero image of three gourmet spice tins arranged in a tasteful studio composition, combining the tin form factor from the first reference with the branding language from the second reference. Brushed metal cylindrical containers with impeccably wrapped labels, embossed details, crisp typography, subtle botanical motifs, rich saffron and forest green color palette with copper accents, soft natural shadows, realistic materials, high-end food branding, clean background, commercial catalog quality, sharp focus, polished and believable packaging design",
  "width": 1152,
  "height": 864,
  "inputs": {
    "referenceImages": [
      "https://assets.runware.ai/assets/inputs/e3d8231c-eabc-4270-97f0-7902647af032.jpg",
      "https://assets.runware.ai/assets/inputs/ec3cdb87-3494-4665-930c-b822d56957df.jpg"
    ]
  }
}
```

**Response**:

```json
{
  "taskType": "imageInference",
  "taskUUID": "cb03d500-1eeb-4809-89b4-20a5bf86f8ca",
  "imageUUID": "074e6874-f707-4a52-9867-30d77f55ae55",
  "imageURL": "https://im.runware.ai/image/os/a13d12/ws/2/ii/074e6874-f707-4a52-9867-30d77f55ae55.jpg",
  "seed": 1503909985,
  "cost": 0.03
}
```

---

### Sculptural Olive Oil Duo (Image to Image)

![Sculptural Olive Oil Duo](https://assets.runware.ai/examples/sourceful-riverflow-2-preview-fast/9dfcd695-4f6b-4f82-8505-813d5dd46068.jpg)

**Request**:

```json
{
  "taskType": "imageInference",
  "taskUUID": "502d6660-6c64-4043-abe8-7ae8dc656aa1",
  "model": "sourceful:2@2",
  "positivePrompt": "Create a premium culinary brand hero shot that merges the design cues of both reference images into a cohesive two-bottle olive oil collection. One bottle tall and refined, one bottle shorter and rounded, displayed side by side on pale travertine blocks with scattered fresh olive branches and a folded linen cloth. Emphasize believable packaging details, elegant Mediterranean-inspired branding, crisp label legibility, natural studio lighting, soft directional shadows, realistic glass and ceramic materials, upscale grocery campaign aesthetic, clean art direction, high product accuracy, subtle warm tones, shallow depth of field, immaculate commercial photography.",
  "width": 1248,
  "height": 832,
  "inputs": {
    "referenceImages": [
      "https://assets.runware.ai/assets/inputs/a2dd2fe3-9d38-46d5-a552-536e5fd51e02.jpg",
      "https://assets.runware.ai/assets/inputs/b1180400-01e4-4d37-8ac1-599b1ccbc3bd.jpg"
    ]
  }
}
```

**Response**:

```json
{
  "taskType": "imageInference",
  "taskUUID": "502d6660-6c64-4043-abe8-7ae8dc656aa1",
  "imageUUID": "8352f8a8-182e-4fef-b754-1b973e574006",
  "imageURL": "https://im.runware.ai/image/os/a08d21/ws/2/ii/8352f8a8-182e-4fef-b754-1b973e574006.jpg",
  "seed": 203200060,
  "cost": 0.03
}
```

---

### Alpine Skincare Gift Ensemble (Image to Image)

![Alpine Skincare Gift Ensemble](https://assets.runware.ai/examples/sourceful-riverflow-2-preview-fast/8ce25e54-9da4-4ccb-a295-3f83a1d2e9f9.jpg)

**Request**:

```json
{
  "taskType": "imageInference",
  "taskUUID": "0c3237fe-8336-403b-9e30-fe254ea0ff3d",
  "model": "sourceful:2@2",
  "positivePrompt": "Create a premium skincare gift set hero image by blending the product design cues from the first reference image with the refined styling and material language from the second reference image. Feature a frosted glass serum bottle accompanied by a matching cream jar and carton, arranged on pale stone with soft linen folds and fresh rosemary accents. Preserve realistic label alignment, believable packaging structure, subtle embossed details, crisp edges, natural shadows, cool alpine-inspired palette of sage, ivory, and stone, luxury commercial photography, clean background, high brand accuracy, polished ecommerce-ready composition.",
  "width": 1248,
  "height": 832,
  "inputs": {
    "referenceImages": [
      "https://assets.runware.ai/assets/inputs/b934957c-3d8f-476f-afef-2a7eda9c2d63.jpg",
      "https://assets.runware.ai/assets/inputs/67c737b2-3965-45e4-aa44-7243522c8f82.jpg"
    ]
  }
}
```

**Response**:

```json
{
  "taskType": "imageInference",
  "taskUUID": "0c3237fe-8336-403b-9e30-fe254ea0ff3d",
  "imageUUID": "d4042568-d8a1-4520-a760-59636a8ff525",
  "imageURL": "https://im.runware.ai/image/os/a01d21/ws/2/ii/d4042568-d8a1-4520-a760-59636a8ff525.jpg",
  "seed": 1141904400,
  "cost": 0.03
}
```

---

### Artisanal Citrus Bottle Arrangement (Text to Image)

![Artisanal Citrus Bottle Arrangement](https://assets.runware.ai/examples/sourceful-riverflow-2-preview-fast/d995967b-7245-4054-b31f-65e2ca405d0f.jpg)

**Request**:

```json
{
  "taskType": "imageInference",
  "taskUUID": "c6fe90a2-2c9e-42c1-ba7d-20927f310da7",
  "model": "sourceful:2@2",
  "positivePrompt": "A high-end commercial product shot of a premium sparkling citrus drink line arranged on pale travertine blocks, three slender glass bottles with consistent brand design, ivory labels with deep olive typography, a small sun emblem, brushed copper caps, visible condensation, sliced yuzu and blood orange placed with restraint, a folded linen swatch, soft directional morning light, crisp natural shadows, elegant Mediterranean-inspired palette, realistic glass refraction, accurate label placement, luxury grocery branding, clean negative space for ad copy, ultra-detailed packaging, photorealistic studio quality",
  "width": 1248,
  "height": 832
}
```

**Response**:

```json
{
  "taskType": "imageInference",
  "taskUUID": "c6fe90a2-2c9e-42c1-ba7d-20927f310da7",
  "imageUUID": "520de7b9-098b-4f6f-9e3f-f2dfeeb5c737",
  "imageURL": "https://im.runware.ai/image/os/a09d21/ws/2/ii/520de7b9-098b-4f6f-9e3f-f2dfeeb5c737.jpg",
  "seed": 1995395687,
  "cost": 0.03
}
```