Adding glowing outline to moving Fortnight character.

codefn Posts: 1 Just Starting Out
edited September 2021 in Post-production techniques

I am still a novice to hitfilm express, but I like editing fortnite videos. I am trying do an effect where I can create a glow outline on a moving person. I can do it on a still but if the character moves then it all goes badly wrong.

8-9 seconds into the example video below, it does exactly what I am trying to achieve

(473) (Tutorial) How to make *INSANE* Skin Glow Buildup (RotoBrush) (PremierePro & AfterEffects) *UNIQUE* - YouTube

would anyone have any tips or ideas? on what effect does this in hitfilm?

thanks Josh


  • Stargazer54
    Stargazer54 Posts: 3,967 Ambassador

    @codefn Fortunately a tracker is built into Express.

    You will need two things. First you need to isolate the figure from the background in its own composite shot. This can be done by drawing a mask around the subject. To keep that moving with the figure, the second thing you'll need is to track the motion and then attach the mask to the tracker. You may also need to turn on animation for the mask (Mask layer, Transform, Path) to adjust its shape throughout the scene.

    Once you have your character isolated create another composite shot of the original footage and then drag the character/mask comp onto a layer above it. Then add your glow effect to the character/mask comp layer.

    Google is your friend here. You'll need to search for and watch some tutorials on HitFilm and motion tracking.

    Here are a couple to get you started:

    And this one. Jump to 1:35 to get right to the tracking part.

  • Triem23
    Triem23 Posts: 20,403 Power User

    So the After Effects "Rotobrush" is something that doesn't have a direct analog in Hitfilm.

    Stargazer54 discussed masks, and he's correct - you can use masks to manually roto the character, but it's a bit fiddly since you're animating the mask around the changing shape of the character and any movement the character does across the screen. A basic roto tip is you don't mask the entire outline, but break the figure up into several masks. mask the head with one spline, torso with another, one for each upper/lower arm/leg, etc. Sounds like more work, but it's not. This approach is what the pros do.

    If you have some money to spend, the Mocha Hitfilm add on can help. Mocha Hitfilm has two functions - 3D Camera Solving and Roto assist. Mocha can be used to track and roto individual shapes in a quarter of the time of manually masking. I'll link some tutorials below.

    Otherwise you cannot track a mask. You might need to use mattes. Here I'm going to copy/paste myself from last week. When you see me talking about "Stewie" then I'm talking about your character.

    Ok, you've figured out you need to "mask" or Rotoscope Stewie's head, but let's discuss "masks" vs "mattes."

    A mask uses data drawn on layer "A" to define a transparent area on layer A.

    A matte uses information on layer "B" to define a transparent area on layer A. The matte can use data from a choice of channels - Red, Green, Blue, Luminance, Alpha, etc. In general most mattes are designed to use data from Luminance or Alpha to drive a single transparency. You can use colored layers to embed multiple mattes in a single image, but that's advanced work.

    I haven't watched this particular tutorial yet, but I'll assume it's helpful.

    Here's an old Javert tutorial from before he worked for FXhome that's a good basic talk on Set Matte.

    QuickFX: Set Matte

    Learn how to use the Set Matte effect to transfer one layers' channel to another in HitFilm 2 Ultimate!Next Video: Canon Rebel T3i UnboxingIf you have any re...

    And my own tutorial, which gets into masks, mattes and keys and the differences/similarities between all. This tutorial was done in Hitfilm Pro 2017, so the section on Mask controls is now obsolete (mask controls have changed), but the principles are correct.

    Essential Hitfilm 08 - How to do 2D Compositing (Maps, Mattes, Masks and Keys)

    Compositing is Hitfilm’s real strength. Mattes, Masks and Keys are the basic tools of compositing. They’re all Opacity Maps, and understanding maps is the ke...

    The FilmSensei tutorial Andy linked above is current, so it shows the proper controls for HF 2021.

    Ok, intro aside, now we can talk about your issue.

    You can't track a mask. The data on the mask is embedded in the image layer. You've already encountered this. The mask itself would have to be animated, and, with Stewart bobbing up an down and his head wiggling from side to side, that's a pain.

    However, you can track a LAYER, and, since a Matte uses layer B to apply transparency to Layer A, creating a MATTE layer is the way to go.

    You'll need to track two points on Stewie. Probably his eyes. You'll create a white plane layer, put it above Stewie, set its opacity to something like 25% (you want to see Stewie under the plane, but want to be able to see where the plane is. then mask the plane to Stewie's head. Then parent the plane layer to the tracked point.

    Now the plane will follow the track. If Stewie doesn't turn his head left to right you might be done. You might still have to animate the mask, but, since the plane layer is tracked, it'll be a lot easier since the track is handling the motion.

    Once the mask is roto'd you can turn its opacity up to 100%, select the plane layer, move it all the way to the bottom of the layer stack and add a Grade Layer just above the plane. You'll need this Grade Layer for the next step.

    Ok, now DUPLICATE the Stewie video and put this ABOVE your insert. Add the Set Matte effect to this top copy, use the Grade Layer as the Source Layer, the Matte Source to Alpha and the Blend to Replace.

    Stewie's head should now be above the insert.

    Why are we using the Grade Layer? Effects in Hitfilm using a "Source Layer" look at the "raw state" of a layer. The raw state is the layer before effects and masks are added, so, if you used the plane layer as the Matte Source the Set Matte effect would see a perfect white plane. A Grade Layer renders everything below itself first, so the "raw state" of the Grade is that render. This means the Grade Layer "bakes in" the mask on the plane, so the Set Matte sees it. You could also convert the Plane Layer and its tracked point to a Composite Shot which would also bake in the transparency.

    Film Sensei has this tutorial, which will cover, in video, what I've discussed here. Yup, despite the title, Jay is gonna use Set Matte.

    That should get you going.

    Last bit - above I said you could use a color matte to define multiple areas of transparency? Here's a tutorial I did for FXhome as an example. I'll use a Comp Shot with text and a colored outline so I can use one matte layer to create two different matted areas for effects and color treatment.

    Ok, here's the Mocha tutorials.

  • tddavis
    tddavis Posts: 5,255 Expert

    Thought I would add this to already extensive list 😁

    Hope you find them all useful.

  • laconstantedeplanck
    laconstantedeplanck Posts: 123 Enthusiast

    Can we just take a moment to appreciate how good, long and accurate are @Triem23 's answers on this forum? I'm amazed 99% of the time I read one of your answers mate.

  • Stargazer54
    Stargazer54 Posts: 3,967 Ambassador
    edited September 2021

    @Triem23 You can track the mask by copying the motion data from the point that you apply the tracking data to and pasting that on the Position property of the Mask's Transform property. Here is what I came with that should work for the OP. (Which is a better method than my original post.)

    This was done by putting the footage in a comp shot then duplicating it. Draw a mask to isolate the subject on the duplicate layer.

    On the duplicate, initiate the Tracker (with the green plus sign) and do a 1 or 2 point track. Since this was a moving shot, I did a 2 point track. Create a Point layer and assign the tracking data to the Point layer. Then copy the Position data of the point and paste it on the Position property of the mask under Transform.

    Turn on keyframing for the Path of the mask and then step through the footage and adjust points to keep the subject inside the mask boundary. After you are happy with the animated mask, then add glow effects to the Duplicate footage layer. Fiddle with the mask's Feather Strength and Roundness in the Controls panel to fine tune the look.

    Here is a screen grab of my layout:

    Expanded View: