Automatic adjust of masks

ritsmer wrote on 3/13/2015, 11:58 AM
Recently I made a video about 3 twin brothers - sitting closely next to each other - all played by 1 single actor.
Because of the very bad light conditions and an impossible background (curtains before a sunlit window) - and the fact that the brothers overlapped each other - I could not chromakey or separate the actor(s) - but had to do some heavy bezier-mask-work - especially as the actor(s) moved quite a bit.

Yesterday evening - making a presentation in neighboring video-makers club - they all were agreed that I should not have done it by a couple of weeks of tedious, keyframing Bezier masking - but claimed that there was software able to keep a once defined mask closely to the actors body, arms, cap etc. when he moved and turned.
Some claimed that After Effects was the perfect choice for this task and would do it in minutes.

Today I have been looking around to find this whizz-bang-auto-rotoscoping software - but found nothing that could have done my work (at a reasonable cost for an amateur, that is).

Now: Have you got any ideas :- )) ??

Comments

Tech Diver wrote on 3/13/2015, 12:30 PM
Check out Mocha Pro. It is designed specifically for such tasks, but be prepared to pay a significant amount. In my opinion, it is by far the best software I have ever invested in.

I am not sure if HitFilm 3, which uses a dumbed-down version of Mocha, can handle it (I don't own a copy). But if so, it is a lot less expensive way to go.

By the way, is "3 twin brothers" six people or do you mean one set of triplets?

Peter
johnmeyer wrote on 3/13/2015, 12:32 PM
Alternative to masking:

Two Cats

Shows how to composite several instances of the same cat into the scene, without a green screen.

Here's a nice tutorial:



You also can use this technique to replace the entire background, like the weatherperson on TV. You may still need to create a few masks, which you place on the top track, but these are "garbage masks" which can be roughly constructed in a few seconds, and which are used to correct any areas where the background shows through the actor in the foreground.

ritsmer wrote on 3/13/2015, 1:01 PM
@Peter: one set of triplets :-)

@johnmeyer: Very interesting - nice exercise for the upcoming weekend here.

edit: link to one of the Bezier masks which must be adjusted every few frames or so:
http://drive.google.com/file/d/0B1ibuKMchwCcaWtZWjNEZzBhc3c/view?usp=sharing


(sorry - for some reason the img= etc does not seem to work with this jpg)
johnmeyer wrote on 3/13/2015, 1:05 PM
BTW, I used a difference mask just last week after someone asked me, three minutes before the performance, to record a 2+ hour reading of Shakespeare's "Measure for Measure." It was, without question, the worst venue for a stage performance: a drawing room at an old social downtown (SF) social club. I locked everything down, but thought they'd lower the lights at some point, so since the camera was going to be unattended, I left the exposure on auto. Too bad, because I wanted to get rid of some horrible wall lights that completely screwed up the background. However, because of the auto-exposure, and proximity of the actors to the camera, whenever they moved close to the camera, the exposure changed, and the mask failed.

However, I did get far enough with my mask to prove that, had I kept the exposure constant, the difference mask would have worked perfectly.

Here is a before/after showing how I was able to replace the static background with one where I Photoshopped out the lights and exit sign:

Grazie wrote on 3/13/2015, 1:35 PM
Keeping the Exposure constant is a must.

Grazie