How to blur faces in DaVinci Resolve

The face turns. The blur keeps going in the direction it was already going. For a few frames, you've got a beautifully blurred bit of background and a completely visible child.

This is where I'd spend my attention when blurring faces in DaVinci Resolve. Getting an oval onto the face is fairly straightforward. Getting it to stay useful through the whole shot is the work.

Resolve gives you three parts to put together: a Power Window to define the area, a tracker to move it, and a blur to change what's visible inside. Blackmagic describes them on its Color page. The steps here follow that documentation; we haven't run a hands-on test of a specific Resolve release.

You don't need a complicated effect to begin. You need a face-sized area that stays covered, including when the person stops cooperating with the camera (which children tend to do).

Make the cut before you do the tracking

Finish the basic edit first. If a shot doesn't contribute anything, cut it now. Every extra second becomes another second of tracking and another second you need to inspect.

Then look through the remaining footage for everyone you want to cover. Don't only count the main subject. A second child at the edge of the frame can be much easier to miss while you're concentrating on the larger face.

Open the Color page, where Resolve keeps its colour adjustments and many effects, and give the face treatment its own correction node. A node is one stage of the image adjustment; keeping this one separate makes it easier to find later. I'd name it something plain, like “Face cover.” When you reopen the project, you shouldn't have to work out which of the skin-tone adjustments was actually hiding somebody.

Add a Power Window and track it

1. Select the clip and the node for the face treatment. Move the playhead, the marker showing your position in the clip, to the first frame where the face needs covering.
2. Open Power Windows, choose a shape and fit it around the face. A circle resized into an oval is a useful starting point.
3. Apply a blur to that node. Check that it's affecting the intended area; Resolve's Color page includes blur effects in its effects library.
4. Select the window and open the Tracker palette. This is the panel that lets Resolve follow movement and move the window with the face. Track forwards from the first covered frame, then watch whether the window follows the face.
5. Drag the playhead slowly through the result. If a cheek or eye leaves the window, pause at the first uncovered frame. Check the window's position and size there, then review a frame that worked before your adjustment as well.

Blackmagic's window, tracking and effects overview explains those controls. Use the documentation for your release if the interface differs. This is a workflow to follow, rather than a promise that every version puts every button in the same place.

Give the window more room than you think it needs

A tight outline can look tidy on a still frame. Then the head turns and a cheek or eye moves beyond it. Leave a margin around the face and look at what happens through the movement.

Pay attention to feathering too. That's the setting that softens the edge of the treatment. It can make the blur less noticeable, but also means the edge doesn't hide as much as the centre. For this job, an unobtrusive effect isn't necessarily a better one.

I can't give you a blur value that makes every face private. A small person in the background and a close-up fill very different amounts of the image. Open the saved video at its full size so you can check the detail people could see. If you need to remove that part of the picture, consider a solid cover you can't see through or a crop that leaves the face out. Our blur, pixelation and cover comparison goes through what each method leaves behind.

Check the places where the shot changes

You can let the tracker save you time while still checking its work. These are the moments that deserve a slower look:

For a brief head turn, try giving the window more room around the side of the face. Then play through the whole turn and check the frames immediately before and after it. If someone walks in front, include the first frame where the face returns in that review. A correct-looking middle frame doesn't tell you whether the beginning of the repair is covered.

If one short moment takes an unreasonable amount of repair, consider dropping it. You can make a good video without saving every second of the original.

Open the export outside Resolve

Export, or save your finished edit, to a new video file. Open that file outside Resolve and play it all the way through. Pause at the awkward moments you worked on, including the first and last frames. Check every child, reflections, any freeze frame you've added and the thumbnail you plan to use.

Listen as well. It's easy to spend an evening checking the blur and stop hearing the full name being said underneath it. A school badge, a familiar front door or a location caption can also tell people more than you intended. Give the file a location and metadata check before sharing.

In a Baby Acrobatics movement video, I want the exercise to be clear. If a difficult shot adds nothing to that, there isn't much reason to keep wrestling with it.