Algorithms

Six algorithms — three ways of thinking about noise. This page is the whole landscape: a comparison table and a decision tree. Details on each algorithm are on its own page.

Where the choice comes from

• Spatial algorithms clean a frame using only the frame itself. Motion doesn't bother them, but they get no help from neighboring frames either.
• Temporal algorithms average neighboring frames. On static shots they give the best cleanliness, but without motion compensation they produce ghosting on motion.
• Block-based ones (BM3D, BM4D) look for similar fragments inside the frame (or among frames) and average whole groups — hence the quality and the cost.

Comparison table

One sentence about each:

• HQDN3D — fast and predictable. Weaker than the rest on heavy noise.
• ATAdenoise — averages neighboring frames by thresholds. Clean on static shots; without compensation it produces ghosting on motion.
• NLMeans — finds similar fragments across the frame and averages them. The best of the spatial algorithms on textures and detail; slow.
• FFTdnoiz — cuts the frame into blocks and cleans frequencies. A good balance; block artifacts are possible at extreme settings.
• BM3D — groups similar 2D blocks. High quality, slow.
• BM4D — BM3D plus time (a ±4 frame window). The quality reference; the slowest, and it requires Analyze Motion.

Decision tree

Five questions — the same as in the interactive quiz on the panel mockup. Answer them in order; the first option that fits is your starting point.

1. Is there motion in the frame?

• No (interview, static scene, push-in without subjects) → go to question 2.
• Yes, a lot (sports, concert, handheld footage) → Motion Compensation Enable + Analyze Motion, and then: time is no object → BM4D; you need it faster → HQDN3D with Balance further right, or ATAdenoise.
• Yes, moderate → HQDN3D or FFTdnoiz; if you see ghosting — Balance further left plus Temporal Gate.

2. How strong is the noise?

• Weak (noise only in the shadows) → HQDN3D with a moderate Denoise.
• Medium → FFTdnoiz, or HQDN3D in two slots with BM3D.
• Strong (high ISO, night footage) → BM3D or BM4D.

3. What matters more — speed or quality?

• Speed (drafts, lots of footage) → HQDN3D or FFTdnoiz.
• Quality (final render of a single frame) → BM3D / BM4D.

4. Do textures and fine detail matter?

• Yes (skin, hair, fabric, foliage) → NLMeans or BM3D; HQDN3D eats them faster than the rest.
• No (flat backgrounds, graphics, interviews) → anything, starting with HQDN3D.

5. Are you ready to hit Analyze Motion?

• Yes → the whole temporal and block-based arsenal opens up: ATAdenoise, BM4D, the temporal part of HQDN3D.
• No → spatial ones: HQDN3D, NLMeans, FFTdnoiz, BM3D. Everything works; you'll just get less cleanliness on static scenes.

Common combinations

Algorithm pages

• HQDN3D — the fast all-rounder.
• ATAdenoise — temporal averaging.
• NLMeans — textures and detail.
• FFTdnoiz — balance.
• BM3D — block-based quality.
• BM4D — the reference with time.

Still stuck — FAQ.