Turn a keyed out object into a regular mask.

[Ivan25827286s9dg]

Hello to all of the nice fellows of this community, i’m trying to figure out whether it’s possible to automatically turn a keyed out object into a regular mask with all of the properties of a regular mask and the mask path for the keyed out object in ” after effects”.

Because, for example even when I save my keyed out object without background as “rgb+afpha” and when importing it back to “after effects” and adding the mask, the mask covers the whole composition size and not the keyed object, even though there is no background under that object. 

I’ve been searching for this for a long time, but unfortunately was not able to find any answers whether it’s possible or not, nor any plug-ins that would specifically serve that function of automatically turning a keyed out object into a regular mask.

Please if you have any idea how it can be done, please share, since unfortunately I have no clue =(

[Rick Gerard]

If you create a high-quality key or matte, you can have a lot more subtlety than you can ever achieve with a mask. Fine details like hair blowing in the wind are impossible to preserve with the Mask tool in After Effects. 

If you have source footage with an Alpha Chanel, you can use Set Matte or Track Matte to create transparency on other layers. If you are only trying to create transparency, there is no need for a mask.

If you want to create a mask to use as a control for an effect like Stroke or Video Copilot's Saber plugin, then the best option would be to use the Alpha Channel on the layer and run Layer/Autotrace and adjust the settings to get the cleanest mask you can get. 

[Ivan25827286s9dg]

Hi, so I would rather want to have some of my objects in the form of mask mainly due to the “mask path” properties ( to be able to copy the mask to the other layers, and to be able to attach other objects to the mask )

For example: I have a blue hat upon my actor, and I want to attach some design to this hat, or stick some other object to it.  Normally I could trace the mask around that hat and then stick the object or the design to it with the mask path. But here I realize that the hat is blue and can be keyed-“masked by its color”, so I remove the blue color with the “keylight”, then I use “fill effect” to turn everything that surrounds the counter of the hat into green, then export it as normal mp4 vid, and import it back, then I eliminate the green color that surrounds the counter of the hat that now is not transparent after importing it back as mp4 file.

Thereby now I have a clear counter of the hat without background. If only I was able to turn it into a regular mask, I would copy the mask and apply it to my original footage, thus having the mask counter following the hat with the mask path I would be able to attach other objects or designs to the masked area making it follow the mask path.

[Rick Gerard]

You can use a keyed layer as a track matte—no need for the mask. You can motion-track any surface using Mocha AE and stick any graphic to that surface. Mocha Pro and LockDown even allow you to track surfaces and mesh warp layers to those surfaces so that Logos look like they are part of a wrinkled shirt or that they bend around someone's arm like a tattoo. 

I think you are way overcomplicating your workflow. I do this kind of thing all the time. If you need a vector path, the track matte layer can be used to generate a very clean mask or vector path that can be used for that purpose. I also do that all the time. 

If you want to cut out another layer with a keyed layer, then a track matte or the Set Matte effect is the most efficient way to do that. If you want to generate a mask from a keyed layer, use AutoTrace/Alpha Channel and adjust the settings so you don't end up with a bunch of masks, then use those masks for motion paths or effects that use paths. If you have a surface that you want to key and need to capture the motion, ensure there is sufficient detail in the Surface and use Mocha AE to track the surface. You can just position data if you choose Translation in Mocha AE or add rotation, scale, shear, and perspective. If you need to attach something to a curved or changing surface, like an actor's shirt, or to put a tattoo on an actor's arm, use Lockdown or invest in Mocha Pro. 

Just replacing an animated character's blue hat with another layer doesn't require a mask, but if the hat is moving, it requires position data from the had that you can get from Mocha AE or maybe even from the Hat layer's position property. 

Attaching layers to a mask requires using the Create Nulls from Paths/Nulls follow Points script, then picking the nulls you want to use or averaging the position of multiple nulls. A path around a character's hat could have a couple of dozen points, and your comp could get very complicated very quickly.  

If you can post a screenshot of the specific timeline you are having problems with and precisely explain the design goals, we can probably help you simplify your workflow. 

[Ivan25827286s9dg]

Thank you for all those methods you provided, honestly saying, I’m still trying to wrap my head around all this information.

I had tried to track objects in Mocha before, and it’s a really good tracker, but still requires manual adjustment of the mask lines while the mask is being tracked, especially if the object is moving and the video is long, it can become quite a chore, but still manageable.

And here the idea came to my mind that if I only was able to automatically mask objects sorely by their color then I could avoid the additional tracking. In this case I could just physically attach the blue elements to my actors such like elements of cloth, blue tape, or just blue color applied to certain parts of the body, then I probably would be able to have those blue parts to be automatically masked -“masked by their color”, and I would be able to separately change the color of those parts, stick objects to them and make them follow the mask ( like scars for example, if i’m sticking them to the blue tapes that are physically sticked to the body, or some design elements if I’m sticking it to the blue elements of cloth). The “automatic masking by color” just seemed to me as a great advantage in comparison with traditional tracking mask methods, especially in cases where I can physically attach those blue elements to the object.

So my general plan was to physically attach some blue elements to certain parts of the body, such as blue tape and stuff in order to be able to use those blue areas for attaching other objects and designs to them.

Is it possible though to track objects in mocha sorely by their color?

Here is a video I could use ( a video with a girl with blue outfit ), I would really appreciate if you could show me ( using this video as an example) what steps are required to stick this design to this blue outfit replacing the blue color with this design, while using the advantage of this blue keyable color for easier tracking.

[Rick Gerard]

Because your actor does a complete 360º turn, you will have to use object tracking, not camera tracking. Maxon has a mobile app that will do body tracking and give you a 3D model called Moves. You then apply the texture to the 3D model and line it up with your footage. I have the app but have not tried integrating it into After Effects, Blender, or C4d. 

This is not a one-step workflow. It may require a rotoscope, 3D modeling, and multiple layers. You may be able to split up the footage and use Lockdown or Mocha Pro's Power Mesh to attach the texture to the blue outfit. 

There is an app called SynthEyes that I have used to generate accurate 3D models from video footage.  

Nothing comes with After Effects or is a free download that will do the kind of surface replacement you want. If I get some time later today, I'll see what can be done with your sample video and jpg texture and post the result.

[Ivan25827286s9dg]

Thank you, it’s my pleasure to learn about all those additional software and methods to do editing, and I will definitely try to explore and wrap my head around them.

Are there any way though to select this blue area by color instead of rotoscoping in this case?  For example, at least in case where the design is just attached and locked within the blue area without preserving the shape of the body underneath , like in the photo I attached below?

in this case, I can place the design under the blue area by the means of keylight, and two layers, but I can't make the design move together with the body. Can I lock the design within this area somehow?

[Rick Gerard]

You can key the blue on a duplicate layer and use that for a Track Matte, but you will still need to do some tracking to get the texture to stick to the subject. Because the model spins completely around, you will have to divide that tracking into at least four separate trimmed and pre-composed layers to get the Mocha Pro's mesh tracking or Lockdown's tracking to stick to the rotating surface.

Just a warning. On the Lockdown product page, there are about 4 hours of training. You're going to have to go through all of that if you want a 3D model with a tracked texture, and you'll need to go through about two and a half hours of training to figure out the mesh tracking workflow and make it work. The same goes for Mocha Pro. Syntheyes may require the least amount of time, but it will require you to combine at least two different apps and figure out how to import and texture your completed 3D models.

An easier workflow to get you started would be to have your model keep most of her body facing the camera for the whole shot.

No matter how you approach the project, it will take a significant amount of time to make a texture stick to a moving subject and make it look like it is part of the scene.

[Ivan25827286s9dg]

Oh, I see, I wish it was possible though to use only the data from the keyed area to do that kind of stuff and avoid rotoscoping. At least now I know that so far it’s not.

Nevertheless, I am grateful for all of your replies, thank you man!

[Rick Gerard]

A good key will avoid Roto because it can be used as a track matte. The problem with your sample shot is not isolating the blue clothing; the problem is that there is very little detail to track, and the model spins completely around. It would probably take me the better part of a day to get good mesh tracking from that shot. The only way to do mesh tracking is to use a 3rd party tool. 

You could motion-track the model, get the texture to stick, and use blend modes to simulate the shape shading, but the only way to make the texture have a believable perspective shift and look like it is sticking to the body is to do some mesh tracking. There is no other option.