Bilateral Blur Node

Bilateral Blur combines two weightings:

• Spatial weight - the spatial distance between pixels (like a regular blur).
• Color weight - the color difference between pixels. Two nearby pixels with very different colors do not influence each other.

Result: homogeneous surfaces (skin, walls, skies) are smoothed, but the edges (the outline of a face, the edge of an object) stay sharp. The node is slower than a standard Blur - use it sparingly and ideally in an optimized chain.

• Effects Library: Tools > Filter > Bilateral Blur
• Quick add: right-click in the Node Editor → Add Tool > Filter > Bilateral Blur

Blur (Gaussian)

Blurs everything the same way. Edges included. Fast. For aesthetic blur, fake DOF, bokeh.

Bilateral Blur

Blurs uniform areas, preserves edges. Slower. For denoising, beauty retouching, cartoon-style stylization.

Rule: to smooth without losing important detail, Bilateral. For a true aesthetic blur, Blur.

• Input (yellow) - image to filter.
• Effect Mask (blue) - optional. Limits the blur to the masked areas (e.g. only on the skin).

MediaIn → Bilateral Blur → MediaOut
     (denoise / skin retouch)

Cleaner for beauty work:
MediaIn → Bilateral Blur → Merge 2D (Foreground)
MediaIn ────────────────→ Merge 2D (Background, Alpha via skin mask)

Spatial Weight

Spatial radius of the blur. Higher = blur over a wider area. Careful: above 10, rendering gets noticeably slower. (default: 5)

Color Weight

Tolerance to color differences. Low = edges are strongly preserved (minimal blur near edges). High = the node behaves more and more like a regular Blur (it tolerates large differences and blurs over them). (default: 0.1)

Red / Green / Blue / Alpha

Turns the filter on/off per channel. For example, lets you smooth only the Red channel (useful to denoise noisy reds without touching the rest).

• Skin smoothing (beauty) - a moderate Bilateral Blur (Spatial 4, Color 0.1) masked to the skin with a Delta Keyer or Polygon mask = smoothed skin, with eyes/lips/hair preserved.
• Light denoising - for low-amplitude noise (low light that is not a disaster), Bilateral with Spatial 3 / Color 0.05 removes the grain without crushing detail. A faster alternative to Temporal Noise Reduction.
• Cartoon / cel shading - Bilateral with Spatial 8 / Color 0.2 → Posterize = clean flat colors with sharp edges, a manga / 2D animation look.
• Prep before tracking - smooth a noisy background before a Planar Tracker = a better lock (the tracker is sensitive to grain).
• Smooth sky - a mask on the sky + Bilateral = a clean sky without banding or noise, without blurring the building skyline.
• Matte painting / concept art - smooth flat areas generated by AI/painting without losing important edges.

• Spatial 3-8 for everyday use. Above 15, render time explodes.
• Color Weight = the critical parameter - start at 0.05 and raise it gradually. You can see the edges "melt" above a certain threshold - stop just before it.
• Pro beauty: Bilateral + Frequency Separation - split the image into low/high frequency, apply Bilateral only to the low frequency and keep the high frequency intact = clean skin with pores preserved. A must in retouching.
• Slow render? Downscale first - apply Bilateral to a half-resolution version then upscale (Transform). Nearly identical result at 4× the speed.
• Do not stack 2 identical Bilaterals - it doubles the time with no real quality gain. Prefer a single Bilateral with a higher Spatial value.
• For heavy denoising, prefer Temporal Noise Reduction (in Resolve's Color page) or a Fuse/OFX node dedicated to temporal denoising.