Motion Tracking & Object Tracking inside Cinema 4D: Guide to Manual / Supervised Tracking

Share this video
  • Duration: 09:15
  • Views: 4797
  • Made with Release: 18
  • Works with Release: 18 and greater

In this video, we'll take a look at how to create, track and supervise the manual trackers.

In order to achieve a good solve, or to track an object, you need to "take matters into your own hands". This is called "Manual" tracking (or Supervised Tracking). In this video, we'll take a look at how to create, track and supervise the manual trackers.



Before we start tracking the object, there are a few things I would like to show you in regards to the workflow and tools involved, so you know what's available and how these tools work. I'll show you these using the previously camera-tracked shot. So let me simplify this. I'm going to get rid of these two cubes, and I'm going to get rid of our constrain tags for no other reason other than I don't want to have them in my viewport when I'm working. So they won't make a difference in this case. I'm going to delete them. The other thing I would like to do, is bring up my motion tracker graph view and dock it over here so I have it in front of me. Now I've got my motion tracker selected. Now I'm going to press H and you can see all these auto tracks. I don't want to have these auto tracks. I'm going to go to the select, and I'm going to select all auto tracks. Excellent. And then I'm going to go and hide the selected. So the auto tracks are hidden, if I press H, there's nothing here. And from now on, any manual tracks I'll create. So I'm going to click here. I'm going to move this up over here so I have a bit of working space. And as you can see in my 2D tracking manual tracking, I don't have any tracks. So let's create a tracker. I'm just going to right click. And what happens is, if a motion tracker object or an object tracker object is selected in the object manager, then the right click actually gives us the tools specific to to this. So you just right click anywhere and you say create user track here. Now someone would ask me of course, where is the here? What does here pertain to? So let me delete this. When it's orange, it means it's selected. And if I press backspace, I can delete it or if I select delete user tracks. And I can multi-select either in my viewport or over here. Let me quickly do that. So right click create user tracks here. Right click user tracks here. Right click user tracks here. And you can see that the unselected manual tracks are Xes. And the select ones are these orange yellow squares which give us the pattern square and the search area square. And if I go here, you can see which one is selected, it's highlighted and I can always use my shift key to select them all and I can delete them all or can select them here and delete them. But anyway that's how it works. Okay. What is here? I'm going to place my mouse pointer over this black feature. And I'm going to right click and say create user track here. And the here is where I originally had my mouse when I pressed the right click. So this is my manual tracker. And I can adjust the pattern and the search area and so forth. Then I have a tracker. And basically I've created a tracker. At the same time, I've created a tracker key frame, a key. Now if I want to see it here, I just press H and here it is. And now it's zoomed in quite a bit. You can see the frame numbers up here. And I'm going to make it slightly smaller, there you go. So on frame 151, which is here, we have a key. What do we do with this? Well, let's go and adjust our interface. And the way I prefer to work, although you can always go and select your motion tracker layout. I like to just rip this off and bring it over here and work with what I have. One thing I'd like you to notice is that the auto-update tracks is by default on and I'll show you what it does. The first thing you need to do after you've created a tracker and you've placed it. That doesn't need to happen in one step. Let me go and delete this one more time. If I want to place a tracker here, I can always create it here, or I can create it anywhere. And then I can grab it from the center and move it here. And it's exactly the same thing. It's the same key frame and the same pattern. So what do we do after this? Well, if we don't do anything and we start scrubbing, you will see automatically that our tracker is red. And that means there is no tracking information associated to the specific frame for the particular tracker. Any track that is not all red for any region of our shot, are just going to be ignored when we do the solve. Excellent. So I'm going to go here, and I'm going to press one of these three buttons. Track bi-directional, track forward or track backward. Now what you need to do for several reasons is only work with track bi-directional. And I'm going to give you a very simple explanation. The first time you use one of these three buttons when you create a new tracker, then every other time you want to add a key and track forwards or backwards, this will not happen. It will only track in the direction you originally designated. So if your original tracking is forward, then from then on, all keys for the specific track will only track forwards regardless of if you press the backwards button or the bi-directional button. This is a slight limitation which Maxon is working on, but for now forget the forwards and the backwards. We always used bi-directional. Having said that, we're on our key. Here it is. Let's press track bi-directional. And you will see in the bottom left that it's processing. It's the loading images, and it will track the specific feature for as long as it can. The lines that show the trajectory of the specific track on our footage are 10 frames in advance and 10 frames trailing. And as we move, you will see that the track is following the feature and when it reaches a point where you can see here that a bit of red enters our pattern. That means that the pattern has changed. At least that's what the tracker believes. And you know something? That's what happened. If you look here, you will see that it stopped, because it can't find the pattern from this point onwards. And if we go to the left... I don't like the fact that this is leaving my screen. It's irritating me. That's why the good developers at Maxon allow us to have the lock view on tracks. If I click on this when my tracker is selected, this is what happens. The footage moves behind, and it's amazing because you can troubleshoot what's going on. You can see how much the tracker is moving in relation to the feature. So let me make this a bit smaller. And we can see the full range of the automatic tracking. So as I've said previously, when we do manual, also known as supervised tracking, we manually set our features and our trackers, but then the actual scanning of the footage to find the trajectory, the position of that feature in our footage is done automatically. That's why it's supervised basically. And we go up to this point. So excellent. Now it's leaving the frame. And there's nothing else we can do about this. So let's go in the other direction. You can see that it lost it. What can we do in this case? Well, there are a couple of things we can do. We can set a new keyframe. And without touching anything else. If I right click and say insert key at track position, it's just going to take a new snapshot of the pattern in this particular frame and use that to see if it can track in both ways. So insert key at track position. I'm not going to touch anything. You saw the calculation took place for about a second and a half and the reason is that the auto-update tracks was selected which means that every time we add a keyframe, or we modify a keyframe, the tracker will try and track automatically without us telling it. And you can see that it actually did quite a good job up to a certain point. Now look at this. Look at this jump. This doesn't make sense. Although this is perceived as a good calculation, a good track, it's obviously not. And these are the parts of your tracking process where you actually need to do the supervision. So move as much as you can so that the tracker is properly locked on the feature and then just insert a key at track position and it's going to recalculate. Let's see what happens in the following frames. And it has done quite a good job. Again let's go to the last frame which we consider to be good. Insert key at track position and so forth. And this is the method we will use to track. And you can see that it took a bit of time because after this frame for some reason the tracker although it does jump, it thinks that it's tracking the feature. This is a type of supervision you need to do. Now this is not the best feature to select. And in this case, I'm going to delete everything because we are actually going to work on the features on our object. In the following video, we will track one of these features from beginning to end using everything we've learned up to this point.
Resume Auto-Scroll?