Absolute bad results with Mocha

I’ve been trying to track a blue rectangle patch on a black book.
For what Mocha claims to be, it seems a simple job
However, Mocha can keep track for a frame or 10 but after that, it’s worthless.
I can adjust the tracking, but in the end I’m better of doing this by hand completely.
Anyone wants to have a go with my footage?
I’ve never have been given such high expectations of software that ended this low.

I created a loose spline around the total plane. I created an exact spline on the blue surface. Tracking works only so-so. I used the tutorial from the iPaq example.
Then I move my hand in front of the blue plane. I corrected the tracking problems by creating a substractive mask around my hand. Still no real succes.
I totally miss the point of using the adjust track function: it shows some really weird random points that I can move around, but they don’t make the tracking any better. Not even after retracking.
Same goes for creating/adjusting keyframes by hand; I had hoped Mocha would incorporate my keyframing when calculating inbetween trackings but it seems they are just standalone keyframes that don’t influence retrackings.
Maybe I should chain the two splines tohether. I don’t know how to do that. I am regarding the tracker as a plane tracker; not as a pixel tracker.
I f anyone could just use my footage, then it would be clear if the footage is bad or if it’s just me.

Hi,
So, the reasons might be many that it isn’t tracking well. You should track as much of the surface as you can. You don’t have to worry about going a little outside the edges of the surface you’re trying to track, you need to look for areas of texture, even if they’re mild areas. You can crank up your % of pixels tracked. And you can crank up the angle and scale amounts mocha looks for.
I can take a look at your footage if you email me. I will send you our ftp footage, but it sounds like you should be able to get results if you get a little creative about where you’re telling mocha to look. Just try not to think about it as a point tracker, rather think of it as a planar tracker and know that tracking any section of one surface will give you a solve for the surface as a whole.
Anyway, I’d be happy to see your footage and give you rock solid tips.
Cheers,
Mary

I’ll take a look at your footage.
Also, adjust track required you to realign those points every time your track slips off. It’s a manual adjustment process.
If you need to track two different areas on the same layer, use an x spline for the first shape, and then use the “add xspline to layer” tool (its the tool right next to the x spline tool with the + on it. Or you can use beziers if you prefer.
But like I said, I’ll take a look at the shot. I reccomend watching the “learn mocha” series on our website though, with Steve Wright, to get a really solid grasp on our program. http://www.imagineersystems.com/learn-mocha
Cheers,
Mary

Hi Geoff,
OK, so here’s the several things that make this shot challenging. I am sending you a mocha file back via email as a sample on how to fix your issue. You will need to apply the sent knowledge and technique over the whole shot.

  1. Your footage is interlaced. Yuck! We always track better if you flatten that interlacing down and re-render your shot for better tracking.
  2. You’re probably not holding the guys fingers out of the track, you need rough garbage mattes for that…
  3. You’re tracking this over almost 1400 frames, over time you will get some drift. You can use adjust track to fix this after the track has run its course. See the example file.
  4. You have significant stabilization warping and lens warping going on that is shifting and warping the surface you are trying to track, again, adjust track will help with this. See the example file.
  5. You have significant scale and angle changes, so you need to up the amount in your angle and scale boxes in your tracking window. See the example file.
  6. When you have extreme side to side angle changes, you need to sometimes start a s=new track from where the surface is flat back to the spot the angle is narrow at again and combine many corner pins together, especially for a shot this long.
    If you track carefully and hold the fingers out and then use adjust track, you should get really nice results.
    Cheers,
    Mary

There is a slight learning curve to it. I’ve just got into Mocha AE myself. I watched one tutorial and tracked an actor for 6 seconds. I’m surprised how accurate the tracking is. Steve’s tutorial really helped me, on the fundamental side.
Did you create a loose spline, then a final spline and attach them together?
I’ll dig up Steve’s tutorial and post it here. It helped me, as I’m new to this too. Just takes getting used too