Seedream 4.0

AI Image Editing Model

Image $$ · 3¢

ByteDance's image generation model with integrated text-to-image and image editing capabilities in a unified architecture, supporting up to 4K resolution

seedream-4.0 API OpenAI-compatible

Access Seedream 4.0 via Lumenfall’s OpenAI-compatible API to generate 4K images and perform complex image edits through a single, unified endpoint. Developers can integrate ByteDance's text-to-image and editing architecture into any application using standard API protocols.

Base URL
https://api.lumenfall.ai/openai/v1
Model
seedream-4

Code Examples

Text to Image

/v1/images/generations
curl -X POST \
  https://api.lumenfall.ai/openai/v1/images/generations \
  -H "Authorization: Bearer $LUMENFALL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "seedream-4",
    "prompt": "",
    "size": "1024x1024"
  }'
# Response:
# { "created": 1234567890, "data": [{ "url": "https://...", "revised_prompt": "..." }] }

Image Edit

/v1/images/edits

Parameter Reference

Required Supported Not available

Core Parameters

Parameter Type Description Modes
prompt string Required. Edit instruction for the image
T2I Edit
seed integer Random seed for reproducibility
T2I Edit

Size & Layout

Parameter Type Description Modes
size string Image dimensions as WxH pixels (e.g. "1024x1024") or aspect ratio (e.g. "16:9")
WxH determines both shape and scale (aspect_ratio and resolution are ignored when size is provided). W:H format is equivalent to aspect_ratio.
T2I Edit
aspect_ratio string Aspect ratio of the output image (e.g. "16:9", "1:1")
Controls shape independently of scale. Use with resolution to control both. If size is also provided, size takes precedence. Any ratio is accepted and mapped to the nearest supported value.
T2I Edit
resolution string Output resolution tier (e.g. "1K", "4K")
auto 1K
Controls scale independently of shape. Higher tiers produce larger images and cost more. If size is also provided, size takes precedence for scale. Any tier is accepted and mapped to the nearest supported value.
T2I Edit
Output size aspect_ratio + resolution
Flexible
Auto "auto" Model chooses optimal dimensions
Custom
1–14142px per side
"WxH" Any pixel dimensions within model constraints
1K 8 sizes
Output size aspect_ratio + resolution
1183 × 887 "1183x887" or "4:3" + "1K"
1024 × 1024 "1024x1024" or "1:1" + "1K"
887 × 1182 "887x1182" or "3:4" + "1K"
836 × 1254 "836x1254" or "2:3" + "1K"
1254 × 836 "1254x836" or "3:2" + "1K"
768 × 1365 "768x1365" or "9:16" + "1K"
1365 × 768 "1365x768" or "16:9" + "1K"
1563 × 670 "1563x670" or "21:9" + "1K"

How these parameters work

size

Exact pixel dimensions

"1920x1080"
aspect_ratio

Shape only, default scale

"16:9"
resolution

Scale tier, preserves shape

"1K"

Priority when combined

size aspect_ratio + resolution aspect_ratio resolution

size is most specific and always wins. aspect_ratio and resolution control shape and scale independently.

How matching works

Shape matching – we pick the closest supported ratio. Ask for 7:1 on a model with 4:1 and 8:1, you get 8:1.
Scale matching – providers use different tier formats: K tiers (0.5K 1K 2K 4K) or megapixel tiers (0.25 1). If the exact tier isn't available, you get the nearest one.
Dimension clamping – if a model has pixel limits, we clamp dimensions to fit and keep the aspect ratio intact.

Media Inputs

Parameter Type Description Modes
image file Required. Input image(s) to edit
Supports PNG, JPEG, WebP.
T2I Edit

Output & Format

Parameter Type Description Modes
response_format string How to return the image
url b64_json
Default: "url"
T2I Edit
output_format string Output image format
png jpeg gif webp avif
Gateway converts to requested format if provider doesn't support it natively.
T2I Edit
output_compression integer Compression level for lossy formats (JPEG, WebP, AVIF)
T2I Edit
n integer Number of images to generate
Default: 1
Gateway generates multiple images in parallel even if provider only supports 1.
T2I Edit

Additional Parameters

Parameter Type Description Modes
enable_safety_checker fal boolean If set to true, the safety checker will be enabled.
T2I Edit
enhance_prompt replicate boolean Enable prompt enhancement for higher quality results, this will take longer to generate.
T2I Edit
enhance_prompt_mode fal string The mode to use for enhancing prompt enhancement. Standard mode provides higher quality results but takes longer to generate. Fast mode provides average quality results but takes less time to generate.
fast standard
T2I Edit
height replicate integer Custom image height (only used when size='custom'). Range: 1024-4096 pixels.
T2I Edit
sequential_image_generation replicate string Group image generation mode. 'disabled' generates a single image. 'auto' lets the model decide whether to generate multiple related images (e.g., story scenes, character variations).
disabled
T2I Edit
sync_mode fal boolean If `True`, the media will be returned as a data URI and the output data won't be available in the request history.
T2I Edit
width replicate integer Custom image width (only used when size='custom'). Range: 1024-4096 pixels.
T2I Edit

Parameter Normalization

How we handle parameters across different providers

Not every provider speaks the same language. When you send a parameter, we handle it in one of four ways depending on what the model supports:

Behavior What happens Example
passthrough Sent as-is to the provider style, quality
renamed Same value, mapped to the field name the provider expects prompt
converted Transformed to the provider's native format size
emulated Works even if the provider has no concept of it n, response_format

Parameters we don't recognize pass straight through to the upstream API, so provider-specific options still work.