Seed Volcengine T2I Config

Seedream is ByteDance's flagship image model, and the honest truth about ByteDance is that its flagship generation products are API-only, full stop - Seedream and Seedance have never shipped open weights. So if you want to poke at the same image model that powers the Doubao ecosystem, a hosted API is the only door, and SeedVolcengineT2IConfig is how that door connects to ComfyUI.

It builds a text-to-image request for the Volcengine ARK endpoint (ark.cn-beijing.volces.com), authenticated with an ARK API key. Output is a MEDIAHUB_IMAGE_REQUEST that goes to MediaHubGenerateImage, which makes the actual call and returns the IMAGE.

Inputs that matter

• model - three Seedream versions, and the names encode their release dates: doubao-seedream-5-0-260128 (the current flagship), doubao-seedream-4-5-251128, and doubao-seedream-4-0-250828. Start with the 5.0 unless you're testing regressions.
• size - 1K, 2K, 3K, or 4K. This is the standout feature here: Seedream genuinely renders up to 4K, which is far beyond what the other image providers in this pack offer. 4K also costs more and takes longer, so it's a deliberate trade, not a default.
• prompt - your text.
• watermark - off by default. Turn it on if you want ByteDance's AIGC watermark baked in (some commercial pipelines require it).
• seed - defaults to -1, which means "random" in this API's convention. Set a non-negative value for reproducible takes.
• response_format - url or base64.

Output: request → MediaHubGenerateImage.

Why you'd reach for it

The 4K output is the reason. If a job needs real resolution - print work, big canvases, detail that survives cropping - none of the other image configs in this pack get there. Seedream's text rendering is also famously decent, which makes it a solid choice when your prompt contains readable words.

Installing it

Same pack install as everything else:

cd ComfyUI/custom_nodes
git clone https://github.com/vantang/ComfyUI-MediaHub.git
/path/to/ComfyUI/python -m pip install -r ComfyUI-MediaHub/requirements.txt

Restart ComfyUI; node under MediaHub/Provider/Seed Volcengine/Image. Dependencies are just requests/Pillow/numpy. You need a Volcengine ARK account and an ARK_API_KEY - that's a ByteDance/Volcengine signup, separate from every other provider here.

Common gotchas

The 4K temptation is real but pricey - a 4K generation is a different cost tier, so don't leave size on 4K for everyday iteration. And the ARK key is scoped to your Volcengine project; if you get permission errors, it's usually the key's project access, not the node. Watch the seed = -1 convention too: the other providers in this pack use different seed conventions, so a workflow you ported from another provider may carry a seed value that behaves differently here.