Hiding faces

Two treatments hide a face. Both are effects, applied with picsart_scene_apply_preset; no look does this, and none is needed. Never answer that nothing is made for hiding a face.

When the request names no treatment ("hide her face", "cover her face", "make him anonymous"), ask before applying anything: suggest blur and pixelate, in that order, in one short message, then apply the one the user picks.

When the request names one, apply it without asking: "blur" is the blur; "pixelate" or "mosaic" is the pixelation.

Blur or pixelate the faces

Put the effect on the media layer and confine it with a portrait / face_skin mask. The mask finds every face in each frame, so on a video the effect follows the faces as they move, and the hair, body and background stay sharp:

picsart_scene_apply_preset({
  "scene": ..., "layerId": "clip", "preset": "effect:gaussian_blur",
  "params": { "blur": 60 },
  "mask": { "provider": "portrait", "segments": ["face_skin"] }
})

picsart_scene_apply_preset({
  "scene": ..., "layerId": "clip", "preset": "effect:pixelate",
  "params": { "pixelSize": 40 },
  "mask": { "provider": "portrait", "segments": ["face_skin"] }
})

Set the strength from the size of the faces, not a fixed number:

• blur about a tenth of the face's width in composition pixels. A face 600 px wide needs about 60; at 40 its eyes and mouth still show through. Small faces in a group shot need 20-30.
• pixelSize about a twelfth of the face's width: 40 for a face 600 px wide.

For an export, any value is fine. For live playback, a blur past 32 costs frame time on a full-frame video, so prefer pixelate there.

What the mask covers

• Every face in the layer. The detector does not tell people apart, so there is no way to hide one person's face and keep another's. When the request points at one person ("her face", "the man on the left") and the frames show more than one face, tell the user before exporting that every face gets the treatment.
• The face, not the hair. To hide more of the person, mask the whole person instead: { "provider": "scene", "segments": ["person"] }. supports.maskProviders in picsart_scene_capabilities lists every region and the platforms that produce it.
• One region per effect. Applying gaussian_blur again replaces the layer's earlier gaussian_blur, mask included.

Check the result

Look at two or three moments where the faces are visible, with picsart_scene_contact_sheet and times. Look at every face, not only the largest:

• Each face is unreadable and the rest of the frame is as it was: the effect works. Export.
• The whole frame is blurred: the mask did not resolve, and the effect landed on the whole layer. Check that the provider and segment are spelled as supports.maskProviders lists them.
• A face still shows: it was too small or turned too far away for the detector at that moment. Tell the user which shots still show a face.

A masked effect runs the face detector on every frame, so a video export takes noticeably longer than one without the mask.