MaaS-Seedream

Capability List

Model ID	Capability Support	Rate limit (max. IPM sheets/minute)
doubao-seedream-5-0-pro-260628	Single Image Generation: Text-to-Image, Single Image-to-Image, Multi-reference Image-to-Image	500
doubao-seedream-5-0-260128 (also compatible with: doubao-seedream-5-0-lite-260128)	Single-image generation: text-to-image, single image-to-image, multi-reference image-to-image Group-image generation: text-to-image group, single image-to-image group, multi-reference image-to-image group	500
doubao-seedream-4-5-251128	Single-image generation: text-to-image, single image-to-image, multi-reference image-to-image Group-image generation: text-to-image group, single image-to-image group, multi-reference image-to-image group	500
doubao-seedream-4-0-250828	Single-image generation: text-to-image, single image-to-image, multi-reference image-to-image Group-image generation: text-to-image group, single image-to-image group, multi-reference image-to-image group	500

Interface and Request Parameters

POST

https://genaiapi-m2.cloudsway.net/v1/ai/ {endpointPath}/seedream/image/generations

Request Parameters

Property	Type	Required	Description
prompt	string	Yes	The prompt used to generate images. Supports both Chinese and English. It is recommended not to exceed 300 Chinese characters or 600 English words. Too many words may cause information to be scattered, and the model may ignore details and only focus on key points, resulting in missing elements in the image.
image	string/array	No	Input image information, supports URL or Base64 encoding. seedream-5.0-lite/5.0-pro/4.5/4.0 supports single or multiple image input. (For images with a total size exceeding 10MB, it is recommended to use URL for delivery) Image URL: Please ensure the image URL is accessible. Base64 encoding: Please follow this format data:image/<image_format>;base64,<Base64_encoding>. Note that <image_format> must be lowercase, e.g., data:image/png;base64,<base64_image> Notes: Input images must meet the following conditions: Image format: jpeg, png (seedream-5.0-lite/4.5/4.0 models additionally support webp, bmp, tiff, gif formats) Aspect ratio (width/height) range: [1/16, 16] (Applicable models: seedream-5.0-lite/4.5/4.0) Width and height (px) > 14 Size: No more than 30MB Total pixels: No more than 6000x6000=36000000 px (This is a limit on the product of width and height pixels for a single image, not a limit on width or height individually) seedream-5.0-lite/4.5/4.0 supports up to 14 reference images. Seedream 5.0 Pro supports up to 10 reference images.
size	string	No	Specifies the size information for the generated image. The following two methods are supported and cannot be mixed. Method 1 \| Specify the resolution of the generated image, and describe the aspect ratio, image shape, or image purpose in natural language within the prompt. The model will determine the final image size. Available values: seedream-5.0-pro (1K, 1.5K, 2K, default 2K. 1.5K has the same price as 1K, with better image generation quality.), seedream-5.0-lite (2K, 3K, 4K), doubao-seedream-4.5 (2K, 4K), doubao-seedream-4.0 (1K, 2K, 4K) Method 2 \| Specify the width and height pixel values of the generated image. See the appendix for common recommended values: Default value: (2048x2048) Total pixel value range: seedream-5.0-pro([1280x720 (921600), 2048x2048x1.1025 (4624220)]), seedream-5.0-lite ([2560x1440=3686400, 3072x3072x1.1025=10404496]), seedream-4.5 ([2560x1440=3686400, 4096x4096=16777216]), seedream-4.0 ([1280x720=921600, 4096x4096=16777216]) Aspect ratio value range: [1/16, 16] Note: When using Method 2, both the total pixel value range and the aspect ratio value range must be satisfied. The total pixels refer to the limit on the product of width and height pixels, not a limit on width or height individually.
seed	integer	No	Default value -1. ~~Only seededit-3.0-i2i supports this parameter.~~ Random seed used to control the randomness of model-generated content. Value range: [-1, 2147483647].
sequential_image_generation	string	No	Only seedream-5.0-lite/4.5/4.0 supports this parameter. Seedream 5.0 Pro does not support this parameter. Controls whether to disable the group image generation feature. Default value: disabled. auto: Automatic mode. The model will autonomously determine whether to return a group of images and the number of images in the group based on the user-provided prompt. disabled: Disables the group image generation feature. The model will only generate one image.
sequential_image_generation_options	object	No	Only seedream-5.0-lite/4.5/4.0 supports this parameter. Configuration for the group image generation feature. Only takes effect when sequential_image_generation is set to auto. Seedream 5.0 Pro does not support this parameter.
sequential_image_generation_options.max_images	integer	No	Specifies the maximum number of images that can be generated per request. Default value: 15. Value range: [1, 15] Note: The actual number of images that can be generated is affected not only by max_images, but also by the number of input reference images. Number of input reference images + number of finally generated images ≤ 15.
stream	boolean	No	Only seedream-5.0-lite/4.5/4.0 supports this parameter. Default value: false. Controls whether to enable streaming output mode. false: Non-streaming output mode. Waits until all images are generated before returning all information at once. true: Streaming output mode. Returns the result of each image immediately as it is generated. Streaming output mode works for both single image and group image generation scenarios.
tools	Array	No	Only seedream-5.0-lite supports this parameter.
tools.type	string	No	Only seedream-5.0-lite supports this parameter. web_search (currently the only available value)
guidance_scale	float	No	seedream-3.0-t2i default value: 2.5 seededit-3.0-i2i default value: 5.5 seedream-5.0-lite/4.5/4.0 does not support this parameter. The degree of consistency between the model output and the prompt, i.e., the freedom of generated images, also known as text weight. The larger the value, the less freedom the model has, and the stronger the correlation with the user's input prompt. Value range: [1, 10].
response_format	string	No	Specifies the return format of the generated image. Default value: url. The generated image is in jpeg format and supports the following two return methods: url: Returns the image download link. The link is valid for 24 hours after image generation. Please download the image promptly. b64_json: Returns image data in JSON format as a Base64-encoded string.

watermark	boolean	No	Whether to add a watermark to the generated image. Default value: true. false: No watermark is added. true: Adds an "AI Generated" watermark in the bottom-right corner of the image.
output_format	string	No	Only seedream-5.0-lite/5.0 pro supports this parameter. jpeg (default) png
optimize_prompt_options	object	No	Configuration for the prompt optimization feature. ~~seededit-3.0-i2i does not support this parameter.~~
optimize_prompt_options.mode	string	No	Sets the mode used for the prompt optimization feature. Default value: standard. standard: Standard mode. Higher quality of generated content, but takes longer. fast: Fast mode. Shorter generation time, but average quality. seedream-5.0-lite/4.5 does not support this mode.

Appendix 1: Recommended width and height pixel values for seedream4.5

aspect ratio	width and height pixel values
1:1	2048x2048
4:3	2304x1728
3:4	1728x2304
16:9	2560x1440
9:16	1440x2560
3:2	2496x1664
2:3	1664x2496
21:9	3024x1296

Appendix 2: seedream4.0

resolution	aspect ratio	width and height pixel values
1k	1:1	1024x1024
	4:3	1152x864
	3:4	864x1152
	16:9	1280x720
	9:16	720x1280
	3:2	1248x832
	2:3	832x1248
	21:9	1512x648
2k	1:1	2048x2048
	4:3	2304x1728
	3:4	1728x2304
	16:9	2848x1600
	9:16	1600x2848
	3:2	2496x1664
	2:3	1664x2496
	21:9	3136x1344
4k	1:1	4096x4096
	4:3	4704x3520
	3:4	3520x4704
	16:9	5504x3040
	9:16	3040x5504
	3:2	4992x3328
	2:3	3328x4992
	21:9	6240x2656

Appendix 3: seedream5.0 lite

resolution	aspect ratio	width and height pixel values
2k	1:1	2048x2048
	4:3	2304x1728
	3:4	1728x2304
	16:9	2848x1600
	9:16	1600x2848
	3:2	2496x1664
	2:3	1664x2496
	21:9	3136x1344
3k	1:1	3072x3072
	4:3	3456x2592
	3:4	2592x3456
	16:9	4096x2304
	9:16	2304x4096
	3:2	3744x2496
	2:3	2496x3744
	21:9	4704x2016
4k	1:1	4096x4096
	4:3	4704x3520
	3:4	3520x4704
	16:9	5504x3040
	9:16	3040x5504
	3:2	4992x3328
	2:3	3328x4992
	21:9	6240x2656

Appendix 4: Recommended Aspect Ratio Pixel Values for seedream5.0 pro

resolution	aspect ratio	width and height pixel values
1k	1:1	1024x1024
	4:3	1152x864
	3:4	864x1152
	16:9	1424x800
	9:16	800x1424
	3:2	1248x832
	2:3	832x1248
	21:9	1568x672
1.5K	1:1	1536x1536
	4:3	1792x1344
	3:4	1344x1792
	16:9	2048x1152
	9:16	1152x2048
	3:2	1872x1248
	2:3	1248x1872
	21:9	2352x1008
2k	1:1	2048x2048
	4:3	2368x1776
	3:4	1776x2368
	16:9	2816x1584
	9:16	1584x2816
	3:2	2496x1664
	2:3	1664x2496
	21:9	3136x1344

Request Body Example

Text-to-Image

curl https://genaiapi-m2.cloudsway.net/v1/ai/{endpointPath}/seedream/image/generations \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $API_KEY" \
  -d '{
    "prompt": "A vibrant close-up editorial portrait, the model has a sharp gaze, wearing a sculptural hat, rich color blocking, sharp eye focus, shallow depth of field, Vogue magazine cover aesthetic style, shot in medium format, with intense studio lighting.",
    "size": "2K",
    "watermark": false
}'

Image-to-Image

curl -X https://genaiapi-m2.cloudsway.net/v1/ai/{endpointPath}/seedream/image/generations \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer ${your_AK}" \
  -d '{
    "prompt": "Keep the model pose and the flowing shape of the liquid garment unchanged. Change the garment material from silver metal to completely transparent clear water (or glass). Through the liquid water flow, the skin details of the model can be seen. The light and shadow change from reflection to refraction.",
    "image": "https://ark-project.tos-cn-beijing.volces.com/doc_image/seedream4_5_imageToimage.png",
    "size": "2K",
    "watermark": false
}'

Multi-Image to Image

curl -X https://genaiapi-m2.cloudsway.net/v1/ai/{endpointPath}/seedream/image/generations \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer ${your_AK}" \
  -d '{
    "prompt": "Replace the clothing in image 1 with the clothing in image 2",
    "image": ["https://ark-project.tos-cn-beijing.volces.com/doc_image/seedream4_imagesToimage_1.png", "https://ark-project.tos-cn-beijing.volces.com/doc_image/seedream4_5_imagesToimage_2.png"],
    "sequential_image_generation": "disabled",
    "size": "2K",
    "watermark": false
}'

Example of Non-Streaming Response

{
    "model": "doubao-seedream-4-5-251128",
    "created": 1757323224,
    "data": [
        {
            "url": "https://...",
            "output_format": "jpeg",
            "size": "1760x2368"
        }
    ],
    "usage": {
        "generated_images": 1,
        "output_tokens": 16280,
        "input_images": 3,
        "total_tokens": 16280
    }
}

Example of Streaming Response

event: image_generation.partial_succeeded
data: {
  "type": "image_generation.partial_succeeded",
  "model": "doubao-seedream-4-5-251128",
  "created": 1757396757,
  "image_index": 0,
  "url": "https://...",
  "size": "2496x1664"
}

event: image_generation.partial_succeeded
data: {
  "type": "image_generation.partial_succeeded",
  "model": "doubao-seedream-4-5-251128",
  "created": 1757396785,
  "image_index": 1,
  "url": "https://...",
  "size": "2496x1664"
}

event: image_generation.partial_succeeded
data: {
  "type": "image_generation.partial_succeeded",
  "model": "doubao-seedream-4-5-251128",
  "created": 1757396825,
  "image_index": 2,
  "url": "https://...",
  "size": "2496x1664"
}

event: image_generation.completed
data: {
  "type": "image_generation.completed",
  "model": "doubao-seedream-4-5-251128",
  "created": 1757396825,
  "usage": {
    "generated_images": 3,
    "output_tokens": 48672,
    "total_tokens": 48672
  }
}

data: [DONE]

Description of Streaming Response Events

Event Type	Description
image_generation.partial_succeeded	In streaming response mode, this event is returned when any image is successfully generated
image_generation.partial_failed	In the streaming response mode, this event is returned when any image fails to be generated. If the failure is caused by failed review, the system will still proceed to request the next image generation task, which means it will not affect the generation process of other images within the same request. If the failure is caused by an internal service exception (500), the system will not proceed to request the next image generation task.
image_generation.completed	It is the last response event of this streaming return, which is returned after all requested images (whether successful or failed) have been processed.

Response Example When an Error Occurs

"error": {
  "code":"BadRequest"，
  "message":"The request failed because it is missing one or multiple required parameters. Request ID: {id}"
}