☁️BizyAir Scribble Lines

Scribble is the loosest, most forgiving ControlNet condition there is. Where Canny wants clean edges and Lineart wants an actual drawing, Scribble is happy with rough, sketchy lines - draw a blob where a head goes and the model figures out the rest. That's what makes it the ControlNet condition beginners reach for first: it controls composition without demanding precision.

BizyAir Scribble Lines is the preprocessor half of that pipeline. It takes a real photo and converts it into a scribble-style line map - thinner, rougher, and less literal than a Canny edge map - which you then feed into a ControlNet Apply node alongside a scribble-trained ControlNet model. The point isn't to draw your own sketch (that's a separate workflow); it's to pull a loose structural skeleton out of an existing image so a new generation follows the same rough composition instead of copying every edge.

Inputs and outputs

The node only takes one required input, image, and offers two things you'll actually touch:

• resolution - the working resolution the extraction runs at, 64–1024 in steps of 64, defaulting to 512. Lower it and you get a cruder, blockier line map; raise it if your source image has fine detail you want the scribble to loosely reflect.
• safe - an enable/disable toggle, on by default. This is the standard ControlNet-aux "safe" convention: it clips the output to a tamer numeric range so the scribble extraction doesn't spit out wildly noisy or broken lines on difficult images. Leave it enabled unless you're deliberately chasing weirder output.

It outputs a single IMAGE - the line map itself - which goes straight into your ControlNet conditioning chain.

Installing BizyAir

Same three routes for every node in this pack. Easiest is ComfyUI Manager: open it, search "BizyAir" by name, hit install. Or clone it by hand:

cd ComfyUI/custom_nodes && git clone https://github.com/siliconflow/BizyAir.git

then restart ComfyUI. Comfy-CLI users can run comfy node install bizyair. Whichever way you install it, you have to set an API key before anything works - the README is explicit that this is a first-use step, done through a "click to login" link that walks you through registering a BizyAir account. Skip it and the node will just fail or hang, because unlike most preprocessor nodes this one doesn't run the extraction on your own GPU - it calls out to SiliconFlow's cloud. That's the whole premise of the pack (Comfy Nodes that run in any environment, hardware be damned), and it's worth knowing going in, since it changes how you debug a stuck node.

Common issues

If the node just sits there or errors out, check the API key first - that's the most common cause with any BizyAir node, and it's easy to overlook since nothing in the UI screams "you're not logged in."

Worth knowing before you install: BizyAir occasionally gets pulled in automatically when ComfyUI Manager tries to auto-resolve a missing node from someone else's shared workflow, and people who didn't ask for it have posted fairly alarmed threads about finding it in their custom_nodes folder. It isn't malware - SiliconFlow is a real cloud AI infrastructure company and this is exactly what it claims to be - but if you only wanted the scribble node and ended up with the whole pack because a workflow you downloaded referenced it, that's expected, not a compromise.

The one thing to actually verify on the ControlNet side: scribble coverage isn't universal across base models. It's been part of every major SDXL and SD 1.5 union since the start, and the newer Flux/Z-Image unions caught up to it too (Z-Image's union added scribble back in a January 2026 revision) - but if you're on a base model whose union doesn't list scribble, this preprocessor will happily produce a line map with nowhere useful to plug it in. Check your ControlNet union's supported conditions before you build the workflow around this.