SeeDream 4.1
What is SeeDream 4.1?
SeeDream 4.1 is the October 2025 refined checkpoint in ByteDance's 4.x image line. The parameter surface is identical to SeeDream 4.0, so swapping is a one-line change. The differences show up in the output: cleaner edges on complex scenes, slightly better prompt adherence when the brief includes more than three subjects, and small improvements in lighting consistency across multi-reference runs. Up to six reference images, eight aspect ratios from 1:1 through 21:9, resolutions at 2K (default) or 4K, and four images returned per call. Pick 4.1 when 4.0 produces mostly-good results that need tightening on the hard prompts. Stay on 4.0 if your style profile is already dialed in.
What's new in SeeDream 4.1
Cleaner edges on complex scenes
Object boundaries hold up better in batched runs. Useful for catalog pipelines that need uniform cutout quality without hand-cleanup.
Better adherence on 4+ subject prompts
When the brief names four or more elements, 4.1 keeps composition coherent more often than 4.0. Useful for product flat-lays and group portraits.
Drop-in upgrade from 4.0
Identical request shape. Existing 4.0 jobs adopt 4.1 with one line changed. Same six-reference cap, same eight aspect ratios, same 2K or 4K options.
Lighting continuity in multi-reference series
Reuse the same six references across a series and 4.1 keeps the lighting more consistent than 4.0 across the full batch.
Best for
Multi-subject compositions
Cleaner handling when the prompt names four or more elements. Useful for product flat-lays and group portraits.
Edge consistency across batches
Object boundaries hold up better in batched runs. Useful for catalog pipelines that need uniform cutout quality.
Lighting continuity in series
Reuse the same six references across a series and 4.1 keeps the lighting more consistent than 4.0.
Drop-in upgrade from 4.0
Identical request shape. Existing 4.0 jobs can adopt 4.1 with one line changed.
Same toolchain at 4K
No new parameters to learn. Just a different checkpoint at the same resolution sizes.
Production marketing assets
Refined output makes it more often shippable without retouch. Useful for fast-turnaround campaigns.
Use cases
Migrate an existing 4.0 catalog pipeline by changing the model name and re-running the regression set; on multi-subject scenes the artifact rate typically drops without any prompt tuning. Pass a four-product flat-lay reference set and prompt for a styled hero; 4.1 holds layout and material consistency where 4.0 sometimes blurred edges. Run a campaign series with the same six references and the same seed; 4.1 keeps lighting and palette steadier across the batch. Use 4K for the press master, 2K for the web cuts, all from the same prompt.
API examples
Call SeeDream 4.1 from any language by POSTing to /v1/tasks. Full parameter docs live at docs.unifically.com/models/image/bytedance/seedream-4.1.
curl -X POST https://api.unifically.com/v1/tasks \
-H "Content-Type: application/json" \
-H "Authorization: Bearer YOUR_API_KEY" \
-d '{
"model": "bytedance/seedream-4.1",
"input": {
"prompt": "An astronaut floating above Earth with the Milky Way in the background",
"aspect_ratio": "16:9",
"resolution": "2k"
}
}'
Successful submission returns a task_id. Poll GET /v1/tasks/<task_id> or set a callback_url on the request to receive the four finished images.
FAQs
People also ask
SeeDream 4.1 is a refined checkpoint of ByteDance's SeeDream 4.x line. Same parameter surface as 4.0 (prompt, up to six references, two resolution sizes, eight aspect ratios, optional seed, four images per call), with refinements in edge consistency and prompt adherence on multi-subject scenes.
Try both with your typical prompts. 4.1 tends to handle multi-subject scenes more cleanly. 4.0 is more conservative and predictable.
Up to six reference images per call.
2K (default) or 4K.
Yes. Pass seed for reproducible output.
