Pano Seam Mask

You've rolled the wrap seam of your 360° pano to the center. Now you need a mask that covers that center strip so an inpainting pass can repaint it. Pano Seam Mask is that mask, and the reason it exists is the same one that killed the crop-chain for rolling: it computes its own geometry instead of making you type numbers into the graph.

What it replaces

The old recipe was SolidMask → SolidMask → MaskComposite → FeatherMask, with the strip's x-position living in the graph as a literal value. Change the canvas size and the strip is suddenly off-center. This node derives the position from width and seam_width - x = (width − strip)/2 - so it's correct by construction at any resolution. You can even think of it as the mask half of Pano Seam Roll, split out for when you've done the rolling yourself.

Inputs

• width / height - canvas size. The mask matches whatever you set here (defaults 1408×704).
• seam_width - width of the strip that gets repainted, in pixels. 96 at 1408 wide is a hair under 7% of the canvas, which is the right ballpark to cover a wrap discontinuity.
• feather - soft flanks left and right, in pixels (default 24). This is where it's better than a blur-based approach: the ramp stays inside the strip, so the mask never grows wider than seam_width. A blur would spill into the good content; this doesn't.

Output is a single mask ready for any inpainting sampler.

When to reach for it

It's the pure version of the seam fix. If you like to control the roll and the mask separately - roll with Pano Roll Horizontal, mask with this, inpaint, roll back - this keeps the graph legible. If you want the whole loop in one node, Pano Seam Roll rolls and emits the mask together and is its own inverse. Both are valid; this one is for people who want the steps visible.

Install

Part of Mickmumpitz-Nodes - MIT, no models, dependencies are just numpy, Pillow and opencv-python. ComfyUI Manager (search "Mickmumpitz") or:

cd ComfyUI/custom_nodes && git clone https://github.com/mickmumpitz/ComfyUI-Mickmumpitz-Nodes.git

Restart, and it's under Mickmumpitz/Panorama as "Pano Seam Mask". A small node, but it quietly removes one of the most annoying re-sync chores in pano work.