BMAB SD-WebUI API I2I

What it is

BMAB SD-WebUI API I2I is the img2img half of BMAB's webui bridge - you hand it an image from inside your ComfyUI graph, and it round-trips that image through a remote Automatic1111-style server's img2img endpoint before handing you back the result. It's the node you'd reach for if there's a checkpoint, LoRA, or extension living only on your webui install that you want applied as a pass over something you already generated in ComfyUI - an ADetailer-equipped install, say, doing a detail pass ComfyUI's own native nodes can't replicate without a lot of setup.

Like its T2I sibling, it does nothing on its own - it needs the api_server connection from BMAB SD-WebUI API Server feeding in.

Inputs and outputs

Alongside the standard generation fields (prompt, negative_prompt, both multiline; steps default 20; cfg_scale default 7; seed default -1), this one differs from T2I in a telling way: it requires sampler, scheduler, and checkpoint as explicit inputs, all populated live from whatever's actually available on the connected server. That means each I2I call can override the sampler and even swap which checkpoint the remote webui is running, per call - T2I doesn't expose that, it just uses whatever the Server node already has loaded.

The required image input is the picture you're sending over for the img2img pass. Two optional sockets: extension (an EXTENSION config from elsewhere in BMAB) and controlnet, which takes the output of BMAB SD-WebUI API ControlNet the same way T2I does.

Outputs mirror T2I: API Server passed straight through so you can chain more calls, and image, the img2img result.

How to install it

Same as the rest of the family - through ComfyUI Manager by searching comfyui_bmab, which pulls in comfyui_controlnet_aux and ComfyUI_IPAdapter_plus alongside it, or manually:

cd ComfyUI/custom_nodes
git clone https://github.com/portu-sim/comfyui_bmab.git
cd comfyui_bmab
pip install -r requirements.txt

with the two dependency repos cloned and pip-installed the same way, then a ComfyUI restart.

Common issues

Because sampler, scheduler, and checkpoint are all dynamic dropdowns queried from the server, they'll show up empty if the ComfyUI graph loads before the webui is reachable - same fix as the rest of this family: get the remote server up and running with its API flag enabled first, then load or refresh the graph.

Swapping checkpoints per-call is convenient but not free: if the webui isn't already caching that checkpoint, this node is effectively triggering a full model load on the remote server every time it runs, which can turn a quick I2I pass into a slow one without any obvious explanation on the ComfyUI side. If a run suddenly takes far longer than expected, check whether you're bouncing between checkpoints unnecessarily.

Denoise strength isn't in this schema at all, which is a real gap if you're used to A1111's img2img tab - there's no obvious dial here for how much the source image should be preserved versus overwritten. Worth testing carefully with a throwaway image before trusting this in a real pipeline.