Inpainting: "Mask Blur"

[a3nima]

Hi! Could someone explain exactly how to use the "mask blur" option and give hints about when to use what values ? Thanks in advance!

[a3nima]

anyone??

[ClashSAN]

try "4-8" https://rentry.org/drfar

[a3nima]

I still dont understand, what it does exactly :(

[enn-nafnlaus]

AFAIK it's like feathering a selection in GIMP/Photoshop

[ProducingIt]

It's still a good question. Anyone?

[enn-nafnlaus]

It's already been answered. It's like featuring a selection in GIMP/Photoshop. Nothing complicated.

[CodeExplode]

When stable diffusion is working on inpainting a region, there's some shared areas around the edge of the mask which it can't change as strongly in each loop, to force a smoother blend with the original image, and force the regions inside to match up more smoothly with the parts at the edges which aren't changing as much. Whether the mask blur works inwards or outwards I'm unsure of (e.g. if you have a masked area 8 pixels wide, and have a mask blur of 4, then you might get no changes because the blur works in 4 pixels from every side).

[Alerdm]

Thx we needed this and not useles and entitled not answering responses

[windowpane]

To answer, this is the relevant code snippet where it gets applied:

if self.mask_blur > 0:
     self.image_mask = self.image_mask.filter(ImageFilter.GaussianBlur(self.mask_blur))

It basically just applies a gaussian blur on the section of the image that has the mask.

[PaperOrb]

I did a few tests and this is what seems to have happened:

1. As the mask blur slider goes up, it increases the radius of this blur BOTH inwards and outwards from the outermost pixel all around the circumference of the mask.
   1a. It seems like these "circumference pixels" get extended beyond the physical border of the mask itself by whatever amount of pixels your mask padding is set to.
2. not only is a blur applied, but like @CodeExplode mentioned, the pixels affected by this blur also change less strongly the higher the mask blur value.

My test involved a 64px wide mask over a 64px wide basketball with a positive prompt of "pirate". I set the mask padding to 32px and set the mask blur to 64px. After generation was done, the basketball was unchanged... except until I zoomed in a ton and saw that the pixels very mildly shifted colors like a mild blur effect in a 96px area all around the very center of the basketball.

My next test was completely the same, except mask blur was set to 0 this time, and the end result was 0 blur around the basketball, but the basketball itself had turned into a circular scene containing a pirate. So tldr:

1. mask blur 64 = more blur + less change or no change (depends entirely on how big your mask + mask padding is)
2. mask blur 0 = no blur + total change

Again, this is what seems to have happened.

[creolobobo]

so it's symmetric, both inward and outward?