✏️ Input Data

This is the most honest node in the pack: it takes the text you type and outputs that text. No detection, no math, no models. Before you roll your eyes, it solves a real annoyance with the pack's main node, and it's also the piece that makes the 📄 Show Data node worth having.

Why it exists

The 🔬 Circle Detection (Hough) node has three optional string inputs: color_tuple_bg, color_tuple_fg, and exclude_circles. You can absolutely type straight into those widgets - and for a one-off run you should. But Input Data gives you a proper STRING output to wire into them, which pays off in two situations:

You want to reuse the same exclude_circles list across several runs or several Hough nodes. Define it once, feed the same wire everywhere, and change one place instead of hunting through widgets.
You want to see what you're passing. Wire Input Data into the pack's 📄 Show Data node and you get a visible text panel on the graph while you tune.

It also works as a general-purpose "here's a string, make it available to the graph" utility, since any node that accepts a forced STRING input will take it.

What it does under the hood

About as little as a ComfyUI node can do. It declares one required input_data field as a multiline string, has INPUT_IS_LIST set to true, and returns the value you gave it, verbatim. No preprocessing, no color parsing, no validation - the detection node does all the parsing downstream. That means garbage in, garbage out: if you type 1,3,x into the exclusion list, you'll get the failure on the Hough side, not here.

The single input and output

input_data - a multiline STRING. This is the only input and it's required.
STRING - the one output, which is just whatever you typed.

For the pack's use case, the practical value is the exclusion list. Run the Hough node once with numbering on, note the numbers drawn on the output image, then type 2,5,7 into Input Data and wire it to exclude_circles to drop those circles on the next run. Since the detection is deterministic, the same circles show up every time - so the exclusion list stays meaningful.

The honest take

Do you need this node? No. The Hough node's optional inputs work fine with plain typed values, and if your workflow is one circle-mask per image, typing 1,3 into the widget is less work than adding a node. Where it earns its keep is when you're iterating on a multi-node graph or want the Show Data display in front of you while you tune thresholds. It's a small convenience, not a feature - think of it as the pack's way of making values visible and reusable instead of buried in widgets.

Installation

It ships in the same pack as the detection nodes, so this is the easy one to get:

cd ComfyUI/custom_nodes
git clone https://github.com/zentrocdot/ComfyUI_Circle_Detection

or search "Circle Detection" in ComfyUI Manager, then restart ComfyUI. You'll find it under 🧬 Circle Detection Nodes, and it works the moment the pack loads - no extra dependencies, no model files, nothing to download.