Silhouette without green screen?

Forum|Forum|8 years ago
February 2, 2018
3 replies
6036 views

I'm fairly beginner in after effects so bare with me.

I filmed dancers as a silhouette and want to create a digital silhouette (video not still). I know I should use a green screen and chroma key it out but I don't have acess to one. Can I mask the background out somehow with this footage? Does it matter that the floor is grey and the backdrop is white?

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Kevin-Monahan

Community Manager

Still working on this ginsiv? Let us know if you need help.

Thanks,
Kevin

Kevin Monahan - Sr. Community and Engagement Strategist – Adobe Pro Video and Audio

timaging

Inspiring

Kevin-Monahan I'm definitely interested. I have to be able to lift a person from a background for some sports promotions. I was going to also try the Rotobrush, but that's not always a perfect solution.

Dave

angie_taylor

Legend

It's worth looking at the individual channels to see if there are any of them that provide enough contrast to use as a matte - this can be a good starting point. You are looking for high contrast between BG and FG. If that exists, use the Calculations effect to accentuate this difference (Often Overlay mode works well as it will boost lights and darks) till you have something you can use as a matte. You can then apply the "Set Matte" effect to apply this as a matte.

Another often overlooked feature is After Effects Paint tools. You can set your paintbrush to "Alpha" only and use black to manual paint out areas that Rotobrush has missed (if using Rotobrush). The great thing is that these paint strokes can be animated and can give a really nice, organic effect. You can also drag the Refine Matte effect after the Paint so that the refinements are also applied to the paint strokes. I have some tutorials on these techniques in my After Effects Learn by Video CS5 and CS6 courses.

D

Dave Merchant

Legend

You could use a curves effect to boost the contrast and turn that footage into something close to a black-white mask around each dancer, assuming they stay in front of the lit areas. Add a hue/saturation effect with sat -100 to make the whites neutral. You're only interested in getting pure white around the edges of the figures and pure black inside, not turning the entire stage white.

You'll then need to mask around each dancer so that all the unwanted areas are removed, and probably keyframe the masks to follow them. Put a solid white layer below to fill in the unmasked regions and you have a silhouette.

The floor looks to be too dark to pull the edges out automatically using this technique. It *might* be possible but you'd need to treat the floor and the wall sections separately, merging them back together with a mask. However from that photo it's looking like the floor will be a rotoscoping job.