Join Todd Kopriva for an in-depth discussion in this video Warp Stabilizer effect controls, part of Motion Tracking and Stabilization with After Effects CS5.5.
Let's walk through the controls on the Warp Stabilizer effect and see what each of them does in detail. I've already applied the Warp Stabilizer effect, and the analysis phase is complete. Changing some of these controls will force re-analysis to occur, but we'll get to those last. We right now have Smooth Motion chosen. So that there's still a little bit of camera motion in the final results. But not the jerky motion that was in the original. Which is no motion, we have to stabilize again, but not reanalyze.
And all the camera motion is removed. But we also have a lot more cropping so we lose more of the image. Stop that preview. If we have Smooth Motion, one of the parameters that we have is smoothness, which allows us to determine how much of the camera motion to keep and how much to smooth out. Method, we can choose between Position which simply moves the entire layer. Position Scale in Rotation which moves the scales and rotates the entire layer. Or Perspective, which does a corner pending operation on the entire layer in edition to moving scaling and rotating it.
All of these three operations are operations done to the entire layer. There are no distortions or warps within the layer. Subspace Warp, the default, is what makes the Warp Stabilizer effect substantially different from its predecessor, the Point Tracker. Point Tracker would also position, change position, scale, and rotation, and do corner penning. We'll stick with the default. The first option in the framing category, Stabilize Only, mostly is sold for instructional purposes. If we preview this, we can see how the layer is being moved to compensate for the motion in the original shot.
Because we're not doing any scaling, we have this black edge around the image, which we don't want. This is something that anyone who's used another stabilization technology has seen before, including the after effects, point tracker used as a stabilizer. Conventionally, you scale up to get rid of these edges. And that's why this option here, Stabilize, Crop, and Auto-Scale is here. It automatically scales up to get rid of the black edges. But when you scale up, you lose some of the image information. Warp Stabilizer effect also has an innovative technology in stabilize synthesize edges.
This, instead of scaling the image up to hide the black areas fills the black areas by synthesizing pixel information. For the current frame, Warp Stabilizer effect will look forward and backward in time looking for pixel information that it can fill in in those black areas. Let's choose this option, notice already that we're zoomed back out a little bit, because we didn't have to do all of that scaling. I'll hit Run Preview. This is somewhat render intensive so ran preview takes longer. The Warp Stabilizer effect is filling in information around the edges but it can't always find information.
So sometimes there are these little holes because. The Warp Stabilizer effect hasn't found any pixels that it can use to fill in that emptiness. Let's Stop this preview. One of the parameters is Synthesis Input Range, which is measured in seconds. The default value, is 0.5, Mean Thorp stabilizer effect is looking forward and backward in time, half a second. If we allow it to look forward and backward in time more, it'll have a greater chance of finding some pixel information that it can use in those black areas.
This takes longer, but gives better results. Let's put this up to 2 seconds, to that lots of information to work with. It'll take a moment to restabilize. And then, when we start the preview, it has to think, so this is somewhat render-intensive. But we're not seeing any of the black empty areas here in the corners as we were before. And we'll let this continue to preview for a while, just to make sure that we don't have any emptiness.
Occasionally, you might see an artifact where the edge information that the warp stabilizer effect is filling in. Doesn't exactly blend in with the image information from the current frame. If that's the case, then you can feather the new information in by increasing the synthesis edge feather value. I'm not seeing a problem in this current movie.
So we won't bother changing that value now. And let's preview this at full speed. I'm not seeing any artifacts there. So, looks like it worked. Some cameras don't record the entire image at exactly the same time. They scan from top to bottom. And this means that if there's much motion within the frame, especially horizontal motion, there are motion artifacts.
These artifacts are referred to Rolling Shutter Ripple. Some people even call it jello cam. We see here Rolling Shutter ripple. Automatically this is reduced somewhat, but if you have an especially large amount of Rolling Shutter artifacting you can choose Enhanced Reduction. We don't currently have any in this shot, so I won't bother turning this to Enhanced. If you're getting non-ideal effects, consider turning on the detailed analysis option. This will do a more sophisticated analysis using more tracking points but it also takes more time. So I'll just turn this on if you find that the results with the defaults aren't good.
And one final option since this is edge cropping, sometimes the image information on the very edge of the frame actually throws off the Warp Stabilizer and doesn't give it useful information at all. So you can crop off a couple of pixels on the left, the top, the bottom or the right and the Warp Stabilizer effect won't pay any attention to those. And that's a quick tour through the Warp Stabilizer effects options.
- Overview of motion tracking
- Manual motion tracking
- Planning and shooting for motion tracking
- Motion-tracking utilities from third parties
- Motion tracking with the point tracker
- Motion tracking with mocha-AE
- Stabilizing motion