Seedream 5.0 Pro

Use seedream-5.0-pro through separate synchronous endpoints for text-to-image generation and image editing. Use /v1/images/generations without image for text-to-image generation. Use /v1/images/edits with one to ten reference images for image-to-image generation and editing.

This guide reflects the public contract updated on July 25, 2026.

Overview

Both endpoints return the final image in the same HTTP response. No task polling is required.
Each request generates exactly one image.
You can select a 1K or 2K tier with an aspect ratio, or pass exact pixel dimensions.
Reference images can use public URLs or Base64 Data URLs.
The response can contain a temporary image URL or raw Base64 data.

Endpoint And Authentication

POST https://api.uniall.ai/v1/images/generations
POST https://api.uniall.ai/v1/images/edits
Authorization: Bearer sk-***
Content-Type: application/json

Text to image: call /v1/images/generations without image.
Image to image or image editing: call /v1/images/edits and provide image.

The Base URL is:

https://api.uniall.ai

If the UniAll.ai console provides a dedicated API address for your account, use the address shown in the console.

Quick Start

Text To Image

curl -X POST "https://api.uniall.ai/v1/images/generations" \
  -H "Authorization: Bearer sk-***" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "seedream-5.0-pro",
    "prompt": "Premium skincare advertising image, a glass bottle on light stone, soft natural light, sharp and readable brand typography",
    "size": "2K",
    "aspect_ratio": "16:9",
    "output_format": "jpeg",
    "response_format": "url"
  }'

Image To Image

curl -X POST "https://api.uniall.ai/v1/images/edits" \
  -H "Authorization: Bearer sk-***" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "seedream-5.0-pro",
    "prompt": "Keep the product shape and label text, then replace the background with a bright studio scene.",
    "image": "https://example.com/source-product.png",
    "size": "1K",
    "aspect_ratio": "1:1",
    "output_format": "png",
    "response_format": "url"
  }'

Exact Dimensions

Pass exact dimensions through size when the output requires a fixed width and height. Do not pass aspect_ratio in the same request.

curl -X POST "https://api.uniall.ai/v1/images/generations" \
  -H "Authorization: Bearer sk-***" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "seedream-5.0-pro",
    "prompt": "Wide product-launch key visual, centered technology product, clean background",
    "size": "2048x1024",
    "output_format": "jpeg",
    "response_format": "url"
  }'

Request Parameters

Parameter	Type	Required	Default	Description
`model`	string	Yes	None	Must be `seedream-5.0-pro`.
`prompt`	string	Yes	None	Instructions for image generation or editing.
`image`	string / string[]	Required for image editing	None	Reference images for `/v1/images/edits`. Accepts public URLs or Base64 Data URLs. Maximum: 10 images.
`size`	string	No	`2K`	`1K`, `2K`, or exact `WIDTHxHEIGHT` dimensions.
`aspect_ratio`	string	No	Model-selected	Supported with the `1K` and `2K` tiers. Do not use with exact dimensions.
`output_format`	string	No	`jpeg`	`jpeg` or `png`.
`response_format`	string	No	`url`	`url` or `b64_json`.
`watermark`	boolean	No	`true`	Whether to add an "AI generated" watermark.

The model always generates one image per request.

Size And Aspect Ratio

Choose one of the following size modes.

Resolution Tier And Aspect Ratio

{
  "size": "2K",
  "aspect_ratio": "16:9"
}

size supports 1K and 2K. aspect_ratio supports 1:1, 4:3, 3:4, 16:9, 9:16, 3:2, 2:3, and 21:9.

Common output dimensions are shown below. Treat data[0].size in the response as the final value.

Resolution	`1:1`	`4:3`	`3:4`	`16:9`	`9:16`	`3:2`	`2:3`	`21:9`
`1K`	`1024x1024`	`1152x864`	`864x1152`	`1424x800`	`800x1424`	`1248x832`	`832x1248`	`1568x672`
`2K`	`2048x2048`	`2368x1776`	`1776x2368`	`2816x1584`	`1584x2816`	`2496x1664`	`1664x2496`	`3136x1344`

When aspect_ratio is omitted, the model chooses the composition from the prompt and any reference images.

Exact Dimensions

{
  "size": "2048x1024"
}

Exact dimensions must satisfy all of these conditions:

width * height must be between 921600 and 4624220, inclusive.
The width-to-height ratio must be between 1/16 and 16, inclusive.
There is no separate 4096-pixel maximum edge. For example, 4200x1000 is valid.
aspect_ratio must not be present because exact dimensions already determine the composition.

Reference Images

All image-to-image and image-editing requests use /v1/images/edits.

Pass a string for one reference image or an array for multiple images:

{
  "image": [
    "https://example.com/product.png",
    "data:image/png;base64,..."
  ]
}

Public URLs and Base64 Data URLs can be mixed in one request.

Public URLs

The file must be directly reachable from the public internet.
The request must not depend on cookies, login state, or custom headers.

Base64 Data URLs

Use the complete Data URL format:

data:image/png;base64,...

The image media subtype must be lowercase. This rule does not require the Base64 payload itself to be lowercase.
Supported formats: JPEG, PNG, WEBP, BMP, TIFF, GIF, HEIC, and HEIF.
Each Data URL image can be up to 30 MB.
A request can contain at most 10 reference images in total.

Response Formats

Input and output formats are independent. A URL input can return Base64 data, and a Base64 input can return a URL.

URL Response

Request field:

{
  "response_format": "url"
}

Response example:

{
  "created": 1784900000,
  "data": [
    {
      "url": "https://example.com/generated.jpeg",
      "size": "2816x1584",
      "output_format": "jpeg"
    }
  ],
  "usage": {
    "generated_images": 1,
    "input_images": 0,
    "output_tokens": 17424,
    "total_tokens": 17424
  }
}

The returned URL may expire 24 hours after generation. Download and store the image promptly.

Base64 Response

Request field:

{
  "response_format": "b64_json"
}

The image item contains b64_json instead of url:

{
  "data": [
    {
      "b64_json": "...",
      "size": "2048x1024",
      "output_format": "png"
    }
  ]
}

b64_json contains raw Base64 data without a Data URL prefix.

Response Fields

Field	Type	Description
`created`	integer	Unix timestamp for the response.
`data`	array	Generated image items. The array contains one item.
`data[].url`	string	Temporary image URL when `response_format` is `url`.
`data[].b64_json`	string	Raw Base64 image data when `response_format` is `b64_json`.
`data[].size`	string	Final output dimensions as `WIDTHxHEIGHT`.
`data[].output_format`	string	Final image format.
`usage.generated_images`	integer	Number of generated images.
`usage.input_images`	integer	Number of reference images.
`usage.output_tokens`	integer	Output usage reported by the API.
`usage.total_tokens`	integer	Total usage reported by the API.

Prompt Positioning And Markup

Express point placement, region edits, text replacement, arrows, sketches, and annotation boxes through the reference image and prompt. No additional request parameter is required.

Replace the sign inside <bbox>100 200 800 900</bbox> with "New collection"
Add a small desk lamp near <point>520 380</point>

Coordinates use the 0..999 range. You can also draw arrows, boxes, or other marks directly on the input image and describe the intended edit in the prompt.

Billing Notes

Each request produces exactly one output image.
The number of input images may affect billing. Use the current UniAll.ai model page as the source of truth.
Output billing is split by actual pixel count: up to 2360000 pixels, or more than 2360000 pixels.
The 1K and 2K labels do not determine billing directly. The final tier is based on width * height from the generated image.
Current unit prices, group multipliers, and final charges are shown on the UniAll.ai model page and in usage records.

Common Errors

Problem	Likely cause	Resolution
The request uses a reference image but does not run as an edit	The request was sent to `/v1/images/generations`.	Send every request containing `image` to `/v1/images/edits`.
Exact dimensions are rejected	`aspect_ratio` was also provided, or the pixel and ratio limits were exceeded.	Remove `aspect_ratio` and verify the exact-size constraints.
Reference image is rejected	More than 10 images were provided, the URL is not publicly reachable, or the Data URL is malformed.	Reduce the image count and verify direct access or the complete Data URL format.
Image format is rejected	The format is unsupported or the Data URL media subtype is not lowercase.	Use a supported format and a lowercase subtype such as `image/png`.
The expected response field is missing	The client is reading `url` while requesting `b64_json`, or the reverse.	Read the field selected by `response_format`.
The client times out before receiving an image	The HTTP client timeout is too short for synchronous generation.	Increase the client timeout and wait for the original request instead of polling a task endpoint.

Overview​

Endpoint And Authentication​

Quick Start​

Text To Image​

Image To Image​

Exact Dimensions​

Request Parameters​

Size And Aspect Ratio​

Resolution Tier And Aspect Ratio​

Exact Dimensions​

Reference Images​

Public URLs​

Base64 Data URLs​

Response Formats​

URL Response​

Base64 Response​

Response Fields​

Prompt Positioning And Markup​

Billing Notes​

Common Errors​

Related Pages​

Overview

Endpoint And Authentication

Quick Start

Text To Image

Image To Image

Exact Dimensions

Request Parameters

Size And Aspect Ratio

Resolution Tier And Aspect Ratio

Exact Dimensions

Reference Images

Public URLs

Base64 Data URLs

Response Formats

URL Response

Base64 Response

Response Fields

Prompt Positioning And Markup

Billing Notes

Common Errors

Related Pages