Replace Text on Chalkboard Behind Teacher

[Walter Soyka]

The roto-brush IS the faster, easier way!

Can you post a screenshot? You might be able to pull a key, but we’d have to see the shot to be able to help better.

Walter Soyka
Designer & Mad Scientist at Keen Live [link]
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
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[Brannon Bain]

Walter,

I was afraid of that. Here is an image of what I am working with.

As you can see, the phone number is behind his head. The 369 section of the number used to read 324. fixing the number is no big deal using a simple mask, but whenever his head passes in front of the 369 portion of the number is when I need to mask him so a chunk of his head doesn’t disappear into the mask for the number.

[Steve Bentley]

That might just work as a key. The board is a decently different color than the rest. Its not going to be perfect because in the old video systems an overly bright shape would produce a dark outline around the shape (see the dark outline around his very white shirt) and that’s going to be a bit noisy. But perhaps with a blur or two and a bit of roto you can get there with minimal pain.
You might also be able to crush the footage little in a separate layer and use his gray hair to step on the chalkboard (and your text) with a screen or lighter color function and no key. You would still need a garbage matte for this or perhaps a really crushed key, but if this depicts the general look of the video, its not that bad at all.
There are always great ways of keying a subject over his own background – its way more forgiving than say a green screen shot.

[Max Haller]

This might not work, but probably worth trying before you try to roto it by hand. Have you tried using the mask tracking to make a mask over his head and just tell AE to track that. It does a pretty good job sometimes. Since he doesnt have long hair it might work. Maybe mask track his head and increase the expansion/feathering when needed.

[Eric Santiago]

I would roto the head all the way through.
And if it’s a static shot, I would honestly create a new clean blackboard and replace.
Place the numbers somewhere else.
Its easier to try and do the rotoscope over a clean slate (pardon the pun) 😉

[Brannon Bain]

Thanks for the suggestion, Steve.

I actually played with keying a bit, but that is one area I am lacking in knowledge, so my results have been pretty poor. Based on your suggestion I will keep experimenting with it, though.

[Brannon Bain]

Okay. Thanks to everyone for the suggestions. I have been trying the “Keying” solution with mixed results.

Turns out that I have 36 episodes like this, so the “roto-ing” solution just won’t be practical in the amount of time I have available.

Here are some examples of my results:

Here, the keyed out mask looks pretty good –

It’s not too bad in this shot –

I am getting a lot of noisiness in the key, which is pretty distracting while the video is playing. Here, you can see an example of dark speckling over the 69 –

And the worst part is the times when the darker parts of the head drift into the number –

If anyone has any suggestions on how I might improve these results, it would be greatly appreciated. This project is killing me…. slowly…. and painfully…

Thanks

[Steve Bentley]

You can always make a copy of your key layer and crush it and blur it and then use it as a garbage matte so the main key doesn’t add noise way beyond the head on top of the text.

[Richard Garabedain]

Your boss is a moron. Just put the phone numbers in a Lower third…No one is going to even try to call that number behind him

[Brannon Bain]

Actually, there are lower-thirds with the correct phone number that appear at regular intervals throughout the program, and have been appearing there for almost 25 years. Despite the fact that the incorrect phone number only appears in 36 of 994 episodes, people still manage to call the wrong number, which actually goes to another client. If simply putting a lower-third would have resolved the issue, I wouldn’t have dedicated time to finding an actual solution. Thanks.