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Denoise

Node icon
Filter

Reduces image noise while preserving edges and detail using Non-Local Means denoising.

The Denoise node applied to a source image — original (left) and result (right).
Side-by-side comparison: the original image on the left and the same image after the Denoise node on the right.

Denoise uses Non-Local Means (NLM) filtering to reduce noise. Unlike simple blurring, NLM compares patches across the image to distinguish between noise and real detail, preserving sharp edges while smoothing noisy areas.

Strength controls luminance noise removal, and Color Strength handles chroma noise separately. The template and search sizes control quality: larger values produce better results but take longer.

Parameters

Section titled “Parameters”

Pins

ImagePixels
InputRequired
MaskMask
InputOptional
ImagePixels
Output

Filter

StrengthNumber
Default: 10.0 Range: 1.0–30.0

Luminance denoising strength. Higher = more noise removed, but may lose fine detail

Color StrengthNumber
Default: 10.0 Range: 1.0–30.0

Color component denoising strength. Higher reduces color noise (chroma speckles) more aggressively

Template Size (px)Integer
Default: 7 Range: 3–21

Size of the patch used for comparison. Larger is smoother but slower. Must be odd (auto-corrected)

Search Size (px)Integer
Default: 21 Range: 7–81

Size of the area searched for similar patches. Larger is better quality but much slower. Must be odd (auto-corrected)

Mask

Mask FromChoice
Default: Luminance
Color image connected to the mask input

How the connected color image is read as a mask

  • LuminanceRead the image's brightness as the mask. The default.
  • AlphaRead the image's transparency as the mask.
  • RedUse the red channel as the mask.
  • GreenUse the green channel as the mask.
  • BlueUse the blue channel as the mask.
Mask FitChoice
Default: None (native size)
Mask connected

How the mask is sized when it doesn't match the image

  • None (native size)Center the mask at its native size, with no resizing. Unmasked regions are unaffected.
  • StretchStretch the mask to exactly match the image dimensions. May distort the mask shape.
  • Fit (letterbox)Scale the mask to fit inside the image, preserving aspect ratio. Letterboxes where needed.
  • Fill (crop)Scale the mask to fill the image, preserving aspect ratio. Crops edges if aspect ratios differ.

Usage Tips

Section titled “Usage Tips”
  • Start with strength 10 and adjust up for noisier images.
  • Increase search size for better quality at the cost of processing time.
  • Use Color Strength independently to target colorful noise speckles.
  • Connect a mask input to denoise only specific regions, targeting noisy areas while preserving detail elsewhere.
Section titled “Related Nodes”