Blackmagic Forum

Wondering if anyone has succesful workflow for animating planar tracked roto. Im a huge fan of the mocha roto tek. Now it looks like you can do soemthing channeling a polygon into planar transform then merging it with footage and then when u animate the polygon it kind of works but the handles change size and it jumps around alot and feels like it wanst designed for this. (see image)

so the idea would be track a moving face basically - curve 1, then create another curve 2 which is the actual roto, link it to the curve 1 then continue fine tuning the curve 2 as it moves.

anyone successful with this workflow or is it still mocha only?

I am not quite sure what you mean with curve 1 and curve 2, but I've done quite a bit of planar roto last year with the Fusion planar tracker and it can be really useful. It's a bit more involved than Mocha (at least from what I gather from the Mocha tutorials which are most likely best case scenarios) but it works well.

The biggest thing to remember is that planar tracker is called *planar* for a reason. It works best when you track something that is basically plane shaped. So tracking a face is not its intended use. It can work if the face doesn't emote too much, or if you only use the tracker for position/rotation/scale instead of full perspective.

Do you have a concrete example of a shot you're working on? If so, I could maybe do a Q'nD tutorial on it, so I could help you and others who deal with the same issue.

hey thanks for answering...im soo glad to hear you have had success.

im pretty experienced in planar tracking in mocha. i realize a face is not perfect scenario but it can as you say often be pulled off for wrinkle removal etc if not too emotive.

curve 1 would be the planar track curve you use to define the planar surface. curve 2 would be the actual roto shape. the idea is to use the planar tracker to drive the roto curves basic positioning then do minor tweak adjustments to the roto curve . this basically would mimic mocha workflow.

again the idea is to be able to tweak the roto curves manually ontop of the planar track. does your workflow accomplish this?

Yep. That's more or less exactly how I did it.
I even did a Q'nD tutorial on wrinkle removal

concrete example..chech thos video here found on youtube. rotoing the tshirt would be pretty easy in mocha. id planar track the logo on the tshirt with basic roto. then id draw a precise curve for roto and link it to the original track,. then id tweak the precise curve while it moved according to underlying planar roto.

at the moment this is 'kind of' achievable in fusion, but the splines act strangely sometimes. my workflow is do planar track on logo and create planar transform then draw a new polygon for the tshirt. just front part not the arms and pipe my polygon into the planar transform foreground channel. now its moving with the roto but you cnat see it unless u merge with the footage in a new merge node. then you cna ocntinue keyframing the polygon. but it seems to slip and shudder a bit giving you the idea your pushing the limits of what it was designed to do

footage here

hehe yeah i had found your video earlier and its good have you tried animating the curve in your matte control node. does it follow the animation? will give it a try now

but you cnat see it unless u merge with the footage in a new merge node. then you cna ocntinue keyframing the polygon.

Well it works that way, because that's the way Fusion works in that sense. The planar transform only transforms the polygon, so to see if it works, you need to apply that polygon to something as well.
So that part is expected behaviour. I did notice that sometimes the mask will "forget" its input size when connected to a planar transform, so it doesn't completely move with the original footage, but if it is slipping and shuddering, then the basic track is off. I usually use 'affine' as my motion type for situations like this, because perspective expects a more or less truly planar track.

It appears that your workflow is almost there, but without seeing the actual footage you're working on and your comp troubleshooting it is pretty difficult.

good point. its too complicated to understand verbally. il make a quick vid later and maybe will help people understand WTH im talking about lol

back later

ok heres a quick vid of what im talking about

I don't see the video. Maybe you've missed a character in the link?

oops here it is

Hi Scott,

That's a really useful video, it captures the issues you're working with very well.
Your definitely on the right track (no pun intended). Some of the issues you're seeing are workflow related, but the weird sizing of the points of the roto is definitely what I consider to be a Fusion bug.

I think it has been reported as well, but it's impossible to check since BMD doesn't keep a public bug tracker.

I've experienced the same things as well. It appears that the points/handles etc are scaled alongside the actual footage. This shouldn't happen of course, but it does. Also as soon as you insert a planar transform tool, the splines get a little weird. The fact that they don't always update at the same time is definitely a bug and not related to your graphics card.

I like to use matte controls to create mattes in combination with the tracked polylines.
The spline in the planar tracker is just to assign the area of information where the tracker should look for patterns, it's not supposed to be exportable, although it would be very convenient if it were possible as a starting point for your manual roto, definitely a wishlist item.

Your example of the cornerpin is accurate, but you're overlooking one option: if you use for example a matte control tool inbetween the BG and the planar tracker, than you can cut out the shape you want the corner tracker to use. So you could cut out a circle and feed that into the planar tracker and it will only show the circle. Internally it will be the rectangle of course, but it respects the alphachannel.

As for feeding the mask into the merge node, just don't do that. Masks aren't meant as creator tools as such and Fusion isn't too well equipped to deal with masks as images (which is probably part of the reason some of the bugs we're seeing are there)

So yeah, you're definitely on the right path.

I like to use matte controls to create mattes in combination with the tracked polylines.
The spline in the planar tracker is just to assign the area of information where the tracker should look for patterns, it's not supposed to be exportable, although it would be very convenient if it were possible as a starting point for your manual roto, definitely a wishlist item.

Can you explain this a bit more. i havent found a workable workflow for this. where are you plging in the matte control. my workflow was backgroun into matte control into corner pin port. didnt work

The spline in the planar tracker is just to assign the area of information where the tracker should look for patterns, it's not supposed to be exportable, although it would be very convenient if it were possible as a starting point for your manual roto, definitely a wishlist item

this is the default behaviour in Mocha as well as parenting masks together which is mind blowingly powerful. I believe Sillhouette has similar technique but in sillhouete can add IK (or maybe its just FK , cant rememeber) to the masks

overall I think Fusion is a bit weak in the roto area although the keyboard shortcuts are cool and u can get the job done

Hey,

Scott, what do you want to achieve in the end ? Is the idea to cover/change the Tshirt logo, like wiping rundmc out in favor of any other one on the same black BG of the same tshirt, right ? Actually I also prefer Mocha in this field (roto, tracking, ..., insert, remove), and it looks like you're stuck where I also was years ago, see ? (so if I can help)...

Now, if I was right so far, the WF problem is about the way you try to assign the track data onto the shape. Basically, you must right click the position : center of your fg new shape and link it to the path of the position : center of the tracked logo... In the meantime, try right clicking any issues parameters to set keys. It's indeed very tough to chat about that here around...

Thank you. This will help immensely in a project I am working on.


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CCleanerHappy WheelsVLC

yeah not looking for specific result with this footage other than trying to replace mocha completely. Love mocha but i dont like using 2 apps when 1 will do. Just a big hassle transferring back and forth and many incidental workflows get lost in translation. I think Nuke in many ways can pull it off.

In my opinion, Fusion's planar tracker isn't ready to replace Mocha. It's a nice step forward, but it's got a way to go before it's usable in as many situations as Mocha is.

+ 1 with Bryan.

totally agree. not in same league as mocha. stil awesome to have it tho. i trust there will be future development