AGSoft Mask Blur

A hard-edged mask is the fast way to get a visible seam. The model treats the boundary as an absolute cliff - regenerate here, touch nothing there - and the result shows it. AGSoft Mask Blur is the five-second fix: it runs a Gaussian blur over your mask so the transition between "regenerate" and "leave alone" is a gradient instead of a wall. It's the boring, unglamorous node that makes an inpaint look finished.

This is one of a small cluster of mask nodes in the AGSoft pack (Fix, Composite, From Color, plus this). Where Mask Fix is the kitchen-sink cleanup tool, Mask Blur is the focused one-trick pony: blur and get out.

How it works

You feed it a mask and it applies a Gaussian blur using OpenCV under the hood (the pack ships opencv-python as a dependency). The mask goes in as the usual ComfyUI MASK tensor - a single channel where white means "regenerate" - and comes back the same shape, just softened.

Two outputs come out, not one:

• mask_out - the blurred MASK, what you'd normally feed onward into your inpaint pipeline.
• convert_mask_to_image - the same mask rendered as a grayscale IMAGE, handy if you want to look at it in a Preview node or pipe it somewhere image-based.

The inputs that matter

• mask - your input mask. Any mask works; the node doesn't care where it came from.
• blur_radius - the Gaussian radius, 0–256, default 5. This is the whole ballgame: higher = softer, more gradual edges. Start at 5 and creep up if the seam persists. Past ~20 it starts swallowing small mask details, so don't go nuclear.
• device - cpu (default) or cuda. The tooltip's honest about it: cuda speeds things up if you have a compatible GPU, but for a mask blur the difference is usually a few milliseconds. Leave it on cpu unless you're batch-processing hundreds.

Installing and common issues

Standard AGSoft install:

cd ComfyUI/custom_nodes
git clone https://github.com/Art-xmaster/comfyui-AGSoft

Restart, or use ComfyUI Manager → "comfyui-AGSoft". The opencv dependency gets pulled automatically; no model files involved.

The classic gotcha is inverted expectations: if your blurred mask looks like it's growing or shrinking the white area, that's not the node lying - it's that Gaussian blur spreads brightness, so very soft edges look wider. If the mask grows too far into protected territory, blur less or run a threshold step (the pack's Mask Fix has threshold for exactly this). And if you're combining a blurred mask with compositing elsewhere, remember the convert_mask_to_image output is a preview convenience, not a second mask source - keep using mask_out for the real work.