Blur 🐦‍🔥

Every OpenCV port has the blur nodes, and this is the plain one - cv2.blur, which averages each pixel with its neighbors inside a rectangular kernel. It's the fastest of the blur family and the least subtle: no weighting, no edge preservation, just a flat average. The node description is refreshingly honest about it: "Default anchor is center of the kernel."

When you'd actually use it

Box blur is a workhorse when the goal is denoising before detection, not artistic softening. Run a box blur before Canny or Hough and you'll kill high-frequency speckle that would otherwise generate a thousand spurious edges. It's also the right tool when you want a uniform, slightly "digital" softness - think smoothing a mask or an edge map, where a Gaussian's fancy falloff buys you nothing.

The inputs

• nparrays: an NPARRAY from the pack's To Nparray node.
• ksize_x (default 3) and ksize_y (default 1): kernel width and height, both must be odd. The quirk here is friendly: ksize_y set to 1 means "use the same as width" - so the default of 3 / 1 is a clean symmetric 3×3 blur, not a weird horizontal streak. Set ksize_y to a real odd value only when you want a deliberately rectangular kernel.
• borderType: pixel extrapolation at the edges - DEFAULT, CONSTANT, REPLICATE, WRAP. REPLICATE (smear the edge pixel) is usually the least surprising; CONSTANT fills with zeros, which can darken borders.

Output

dst - the blurred NPARRAY, same shape as the input. Route it through To Image to preview, or straight into a detection node.

Install

ComfyUI Manager → search ComfyUI-ArchiGraph, or:

cd ComfyUI/custom_nodes
git clone https://github.com/vincentfs/ComfyUI-ArchiGraph

Restart and run the pack's install script once for the OpenCV dependency. Nothing else to download.

Gotchas

• ksize_y = 1 is shorthand for "same as width," so don't read it as a 1-pixel-tall kernel. If you do set both, they must be odd.
• CPU-only, like the rest of the pack's OpenCV section - irrelevant for a single blur, worth knowing if you're blurring thousands of frames.
• It's a sibling of the pack's Gaussian Blur and Median Blur nodes. Reach for this one when you want it fast and uniform; Gaussian for natural softening; Median when you need to kill salt-and-pepper noise specifically.

If you need a blur that's boring on purpose - denoise then detect - this is the one. Don't expect character, that's not the job.