Masking Problem

mjroddy wrote on 6/9/2006, 5:14 PM

We're trying to have text move behind an actor on screen in live footage. On track 3 we have the master footage. On track 1, we have a duplicate of that footage with the actor masked out. On Track 2, we have our text. The effect is fine, BUT there is a fine line around the mask that is noticeable. We tried to feather the mask but it makes matters much worse. It appears to be a one pixel black line around the entire mask. How do we get rid of it?

Thanks for all thoughts, ideas, and suggestions.

Comments

Spot|DSE wrote on 6/9/2006, 10:52 PM

Can you use a luma, levels filter, or even Gaussian blur set to pre on the mask to get it to clean?

Grazie wrote on 6/9/2006, 10:52 PM

Haven't tried EXACTLY this, but I have used Gaussian Blur to some success with other sharp edges. Try about 0.001 on both axis.

Grazie

Grazie wrote on 6/9/2006, 10:53 PM

. .. AArrrrrgghh . .yah got me SPOT! . . too quick! - g

mjroddy wrote on 6/10/2006, 1:40 AM

I don't quite understand. How do I "set it to pre?"
Also, how can Luma or Levels help.
When I applied the blur, it blurred my whole pic, not just the edges.
Sorry I'm being so thick...

farss wrote on 6/10/2006, 2:21 AM

How are you generating the mask?

I just tried this with generated media using a bezier mask and no sign of a black line. I could make the mask a little less sharp by adding Feather to the mask but it doesn't really need it.

Bob.

Grazie wrote on 6/10/2006, 3:39 AM

" We tried to feather the mask but it makes matters much worse."

Bob? Maybe you could explain further?

Grazie

farss wrote on 6/10/2006, 4:06 AM

Wish I could but that wasn't my comment!

I'm trying to find out HOW he generated the mask,

CK, bezier, garbage matte, etc?

I suspect the problem is coming from the mask but without knowing how he's generating the mask I can't simulate the problem.

Bob.

Edward wrote on 6/10/2006, 4:12 AM

is it a bezier mask?

If it was a bezier mask, what resolution was the preview video at when you created it, Draft, Preview, Good, Best?

You need to create your Bezier mask while previewing it at 'Best Full'. Anything less won't give you an accurate view in your event pan/crop window. Viewing it at BEST FULL will. maybe then you'll see the black lines disappear. Try to hug the masking edges to the object you're trying to cutout. (I know, I myself am saying, 'duh')

Very similar to my past projects. I hope I helped, and didn't miss completely.

Grazie wrote on 6/10/2006, 4:12 AM

Yup - exactly. Maybe this little chat we are having will again stimulate our friend to "explain" further.

I'd love to get me hands on his VEGGIES!! - Is that legal? LOL!

Regards,

Grazie

Edward wrote on 6/10/2006, 4:14 AM

>>>I'd love to get me hands on his VEGGIES!! - Is that legal?<<<

Only in Europe... haha.

PEEECE!
Ed.

Spot|DSE wrote on 6/10/2006, 7:15 AM

Matthew, to set any effect/filter to Pre, you need to toggle the pre/post toggle at the left of the keyframe timeline. Looks like a sidemounted triangle

mjroddy wrote on 6/10/2006, 3:54 PM

Thanks very much everyone.
I'm using bezier masks from the Pan/Crop tool.
I don't remember the resolution I was using, I'll check that out when I get back to work.
I'll also try the pre/post thing that Mr. DSE suggests.
I've tried to duplicate the problem here at home, but it's behaving the way it SHOULD, not the way it is at work, so duplicating the problem is ... er.. a problem.
Monday I'll try the above suggestions and see what there is to see.
If the problem persists, I'll post some stills and, maybe even let you get your hands on my veggies... I'm pretty shy, though... ;-)
Thanks again!

mjroddy wrote on 6/12/2006, 12:10 PM

I didn't know if it would help here for me to post a followup, but in case this is of use, here goes:
I came back to work (because I have to do that kind of thing) and played around with that masking issue once more.
I found a couple things out, including (based on your suggestions above) the solutions (yes, there was more than one).
First, setting quality to Best Full didn't help.
What I had was, as mentioned, a clip with an actor on V1; A Duplicate of that clip on V3 with a Bezier Mask following her movement; On V2, I had some text.
On V1 & 3, I had a gentle Colour Curve and Brightness & Contrast. Turns out, those were the culprates. Turning them off solved the problem.
But since I wanted that look, I had to find a way to keep them. Putting them down stream worked - on the Project Level. Since, in this case, we corrected all clips identically, this worked with no sweat (all clips were shot in the same room under the same conditions, so a single CC worked fine).
Another solution (working off what Mr. Spot suggested) was to switch the effects from Post to Pre. That got rid of the offending line as well.

So, as it turns out, it's all good - with a little fanangling.

Thanks for all your help and suggestions!