//:

You've probably seen this effect many many times before, and you've probably even done iot yourself in photoshop with the liquify tool. Stretching noses, shrinking eyes and making people look really really stupid

Today we're gonna do the same, but with moving images and people moving. Using tracking and grid-warping we're going to warp my colleague's face till he's beautifull :)

This is my good friend and colleague at BUG, Espen Morild and he's the subject of the day.

The first to do is load the sequence in the comp, and add a tracker node to it. Add two trackers and track the corners of the eyes all the way. The reason for adding two trackers is because fusion's tools can calculate not only position data but scaling and rotation relative to the rest of the face.

Source

Then add a gridwarp node after the tracker and go into the "Source" mode of the node.

Press the "Edit line" button and turn off the "View Grid" button, then start drawing a polyline mask around the subjects face to get the basic outlining. When you're done, press the "View Grid" button back on to se the warping grid applied within the drawn line.

Now we need to hook it up to the tracker, and we're doing that by right-clicking on the "Center" item on the gridwarping and selecting Connect to-> Tracker1 -> Tracker 1 offset Position.

Now the grid have moved abit to match the tracker1's offset position and you need to move it back manually, but fortunatly for you the original gridlines are still visible.

Press the "Selected" button and select all the grid lines and move them to match the original gridlines, now everything should be lines up and the position have been tracked to the gridwarper. Now do the same thing with the "Angle" property, right click select Connect to tracker1 and choose Tracker1 Unsteady Angle and the rotation have been fixed. Repeat the same procedure for the Scale and choose Unsteady Size.

Destination

Now we've tracked and fixed the source of the grid warper to the subjects face we need to switch to the tab "Destination". Press the "Copy source to destination" button and the grid will switch to the one you've made. Now connect the position, rotation and scale again using the same method as in the source tab. Switch to the render tab and turn off the "Black background" to see the image completly.

Warp-it

In the destinations tab you can now move the grid points to distort/warp the face to your liking and the warping will stay fixed on the subject. Pretty neat! You can also use a differnce matte to generate a mask if you want to add grain and stuff to the newly stretched parts. Also the render tab of the gridwarp node has options for motion blur. And holy shit , it can even be animated :)

-the0