Doubao image generation

Doubao Seedream models use the unified image generation endpoint. Suited to text-to-image, and also supports image-to-image via an array of references.

POST /v1/images/generations

Choose the Seedream model with ; sizes map from aspect ratios to concrete pixel values (see the size mapping table below). Responses follow an OpenAI Images–compatible shape.

Available models

Headers

Name	Type	Required	Description
	string	Yes	Request authentication. Use a Bearer Token, for example:
	string	Yes	Request content type; must be

Request body

Name	Type	Required	Description
	string	Yes	Doubao Seedream model name; see Available models above
	string	Yes	Generation prompt. Recommended for both text-to-image and image-to-image
	integer	No	Number of images; recommend . If omitted or explicitly set to , the unified layer falls back to
	string	No	Output size as width×height pixels. These Doubao models usually map fixed aspect ratios to fixed pixel sizes; see Size mapping below
	array<string> | string	No	Optional reference image input: image URLs or a Base64 array; for image-to-image and multi-reference cases
	string	No	Optional response format, commonly or . If omitted, the final format depends on upstream and the gateway compatibility layer
	string	No	Quality field. Accepted by the unified image DTO; whether it is consumed depends on the final upstream
	string | object	No	Style field. Accepted by the unified image DTO; whether it takes effect depends on the Doubao channel
	string | object	No	Background control field. Accepted by the unified image DTO; whether it takes effect depends on the Doubao channel
	boolean	No	Explicit watermark switch. differs from omitting the field

Size mapping

Aspect ratio	value

Request example

Text-to-image

curl -X POST https://octopusx.ai/v1/images/generations \
  -H "Authorization: Bearer <token>" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "doubao-seedream-4-0-250828",
  "prompt": "A cute little sea otter floating on the ocean surface in sunlight, cinematic look, high-definition detail",
  "n": 1,
  "size": "2048x2048"
}'

Image-to-image

curl -X POST https://octopusx.ai/v1/images/generations \
  -H "Authorization: Bearer <token>" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "doubao-seedream-4-5-251128",
  "prompt": "Keep the subject and mood from the reference, and redraw as a more premium ad poster",
  "n": 1,
  "size": "2560x1440",
  "image": [
    "BASE64_IMAGE_1",
    "https://example.com/reference-2.png"
  ]
}'

Response example

200 - URL

{
  "created": 1735689600,
  "data": [
    {
      "url": "https://.../images/doubao-img-abc123.png",
      "revised_prompt": "A cute little sea otter floating on the ocean surface in sunlight, cinematic look, high-definition detail"
    }
  ]
}

200 - Base64

{
  "created": 1735689600,
  "data": [
    {
      "b64_json": "iVBORw0KGgoAAAANSUhEUgAA...",
      "revised_prompt": "A cute little sea otter floating on the ocean surface in sunlight, cinematic look, high-definition detail"
    }
  ]
}

Response fields

Name	Type	Description
	integer	Generation timestamp
	array<object>	Array of generation results
	string	Returned image URL
	string	Returned image Base64 data
	string	Some upstreams return a revised prompt

Notes

INFO

Unlike Gemini, these Doubao endpoints do not take an aspect-ratio enum. Map the ratio to a concrete pixel size first, then set that size on .

Related endpoints

• Image APIs overview
• Error codes