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Blur

Node icon
Filter

Smooths an image with six blur algorithms: Gaussian, Box, Median, Motion, Bilateral, and Edge-Preserving.

The Blur node softens an image using one of six algorithms. Gaussian is the standard all-purpose blur. Box is faster but lower quality. Median removes noise while preserving edges (great for salt-and-pepper noise). Motion simulates camera motion in a direction. Bilateral smooths flat areas while keeping edges sharp. Edge-Preserving is the most sophisticated, creating a painted, stylized look.

The “Blur Alpha” toggle controls whether transparency is also blurred. Turn it off to soften the image while keeping sharp transparent edges, which is useful for sprites.

Parameters

Section titled “Parameters”

Filter

TypeChoice
Default: Gaussian

Algorithm

  • GaussianThe standard smooth blur. Natural-looking falloff, good for most purposes.
  • BoxSimple averaging blur. Faster than Gaussian but with less natural falloff.
  • MedianReplaces each pixel with the median of its neighbors. Excellent for removing salt-and-pepper noise while keeping edges sharp.
  • MotionDirectional blur that simulates camera movement. Set the angle and distance.
  • BilateralSmooths flat areas while preserving edges. Great for skin retouching and noise reduction without losing detail.
  • Edge PreserveThe most sophisticated option — creates a painted, stylized look while keeping important edges intact.
RadiusNumber · px/%
Default: 5.0 Range: 0.0–200.0

Blur strength; 0=none, higher=more blur

Blur AlphaToggle
Default: true

Also blur alpha; uncheck to preserve sharp edges

AngleNumber
Default: 0.0 Range: 0.0–360.0

Motion blur direction; 0=horizontal right

DistanceInteger · px/%
Default: 20 Range: 1–500

Motion blur streak length

DiameterInteger
Default: 9 Range: 1–15

Bilateral neighborhood; smaller=faster

Color ThresholdNumber
Default: 75.0 Range: 10.0–150.0

How similar colors must be to blur together

SpreadNumber
Default: 75.0 Range: 10.0–150.0

How far the smoothing reaches

AlgorithmChoice
Default: 0 Range: Recursive/Normalized Convolution

Edge-preserving filter: Recursive/Normalized Convolution

SmoothnessNumber
Default: 60.0 Range: 1.0–200.0

How much the image is smoothed

SimplifyNumber
Default: 0.4 Range: 0.01–1.0

How much detail is flattened

Mask

Mask FitChoice
Default: None

Mask sizing

  • NoneCenter the mask at its native size — no resizing. Unmasked regions are unaffected.
  • StretchStretch the mask to exactly match the image dimensions. May distort the mask shape.
  • FitScale the mask to fit inside the image, preserving aspect ratio. Letterboxes where needed.
  • FillScale the mask to fill the image, preserving aspect ratio. Crops edges if aspect ratios differ.
Notes

Radius shown for Gaussian/Box/Median only. Angle/Distance only applies to Motion. Diameter/Color Threshold/Spread only applies to Bilateral. Epf * only applies to Edge Preserve. Mask Fit only visible when mask is connected.

Pins: image (required), mask (optional). When mask is connected, the effect is blended with the original using the mask (white = full effect, black = original).

Usage Tips

Section titled “Usage Tips”
  • Bilateral blur is great for skin smoothing because it removes noise while keeping edge detail.
  • Use a small Gaussian blur (1–3) before Edge Detect for cleaner results.
  • Motion blur with a large distance creates dramatic speed lines.
  • Uncheck Blur Alpha when working with game sprites to keep crisp silhouettes.
  • Connect a mask input to blur only specific regions, such as selective focus or privacy blurring.
Section titled “Related Nodes”