Let's say you need to blur four faces. Put four copies of the clip in tracks 1 to 4. Crop the clip in track four to only show face four. Repeat that for track 3 and face 3, etcetera. Then apply the mosaic filter and travelling matte on each of the tracks.
Ahhh....one would think that this would work but for some reason when I try it the track mattes seem to cancel each other out and I can only see the original clip.
Each face/track needs its own track matte.
If you haver 4 faces you will need four videotracks and four track matte. In total 9 tracks will be filled.
video 1: clip
video 2: clip with track matte effect set to track 3
video 3: the matte for face 1
video 4: clip with track matte effect set to track 5
video 5: the matte for face 2
I would do this in After Effects myself. Much easier, espacially with it's Tracking tool.
Here's another way to accomplish this, and in a way that I think is a bit tidier:
- Create a sequence called "MATTE" with as many tracks as faces you need to blur out, plus one.
- Create an oval or face-shaped graphic using the Titler or Photoshop, or other graphic application. Be sure the oval is pure white, with a transparent background.
- Drop your video clip on V1, and then drop an instance of the oval graphic on each of the remaining tracks.
- Position and animate each oval graphic over a face. If the people in the shot are not moving, but the camera is, you may be able to animate the position of just one of the ovals, and then copy and paste the motion effect to the rest of the oval graphic instances. Then, alter the Anchor point property to adjust the absolute position; the relative animation will remain consistent.
- When you're done animating the ovals, turn off the visibility of your background video layer on V1.
- In your final sequence, place another instance of your video clip on a track directly above the first. Drag the MATTE sequence from the bin onto the track above the duplicate clip. So if your original clip is on V1, a copy would be on V2, and the nested MATTE sequence will be on V3.
- Apply the blur/mosaic filter and tweak the settings to taste to the clip instance on V2. Add the track matte key effect, and set the Matte parameter to V3 (or wherever your MATTE is) and set the Composite Using parameter to Matte Alpha. Immediately, you should see the track matte work.
- You can also apply a blur (for instance, Fast Blur) to the MATTE nested clip in order to soften the edges of the matte a bit. Adjust to taste.
- If you need to adjust the position of one of the "faces", just go into the MATTE sequence and tweak it. The changes will be automatically reflected in the final sequence.
Hi Wine Snob, as I said in an earlier post this doesn't work for multiple faces as the track matte seem to cancel each other out.
That is why I suggested using crop.
Nice explained Colin, thanks.
I tried your suggestion as soon as I got to work this morning. It was perfect and your instruction were very easy to follow.
You're very welcome--I'm glad it worked for you. Now you can protect the innocent all day long ala COPS