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how to do this?
Posted by Salud Diaz on July 7, 2005 at 6:59 pmI have a video of a girl riding a bike and I need to create a mask (I believe thats what I need but Im not sure) so while she rides a bike words will come across the screen, but once the words goes through her it will go behind her instead of in front of her. How can I do this?
Thanks,
Salud Diaz replied 20 years, 10 months ago 6 Members · 7 Replies -
7 Replies
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Aroonzfx
July 7, 2005 at 7:12 pmhi
u will hav to roto .. or as u said mask the needed portion
and then place the txt layer below the masked one and animate the
text so taht it goes underneath the girl as u wished..hope it helps
all the best for ur projectarooooooooonz
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Michael Munkittrick
July 7, 2005 at 7:15 pmThat is commonly called rotoscoping and it requires that you will create a new layer of the original shot and draw a mask around your subject. Then, use a frame-by-frame mask modification to keep the mask around that subject allowing for items to appear to pass behind it. It’s a pain if there are a lot of little edges to track, but it looks stellar if done well.
Michael Munkittrick
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Salud Diaz
July 7, 2005 at 7:16 pmwhere can I find a tutorial on the topic?
PS: Is there a way to do a RotoBezier and convert it to autotrace and then mask?
sorry I’m a bit confused
Thanks, -
X-claim
July 8, 2005 at 12:44 amAnd remember to roto it by doing keyframes at each end first then keep dividing in half, that way you dont always have to use so many keyframes/time, and AE can do some of the work for you.
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Steve Roberts
July 8, 2005 at 1:53 amAfter keyframing the start and end, I tend to keyframe the mask(s) at the extremes of the object’s motion, allowing AE to interpolate the mask shape between those extremes.
The keyframes then end up on whichever frames are appropriate.
Steve
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Shannon
July 8, 2005 at 4:45 amDo yourself a favor. Use as few point in your mask as possible. If you dont know how to manipulate the splines that make up the masks in AE, then read about all your options in help before you start.
Also, dont expect to use one mask for the hole thing. break it up. ie. one for her head, one for her torso, one for each arm. Sounds crazy but it will help keep it cleaner in the long run.
Others have given good advice when they mention keying the start and end frames first. What they mean is, make your masks perfect on frame one, then set a shape keyframe for them. Next go to the last frame and once again make perfection and set a key on shape. Now, go to the midway piont through the comp and see where AE has left your masks. Chances are the “head” mask is pretty close, but you’ll need to tweak others. Set a shape key. Now split up the first half and last half into quarters and do the same. Keep pairing down this way. This, as others have said, lets AE do a good portion of the work for you as it attempts to interpolate between keyframes.
Lastly, when placing the splines on your image, dither to just outside of the line of the subject to be masked, not on our inside the lines. Later you can contract and feather your masks a bit if needed.
You may be best off using the rotobezier splines which means just hitting that checkbox, and read help to learn how to control the hardness or angle on the points. Remember, USE ONLY AS MANY POINTS AS YOU NEED to describe your outlines.
With love, from a dude who lives the roto hell all day. Every day.
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Salud Diaz
July 8, 2005 at 2:55 pmThanks for all of you *-) But here’s how I’ve done it:
1. Duplicate the “bike” layer.
2. Create a mask on the top layer. The mask should outline the girl on bike. You only need to mask the section of the girl that the words will go behind. Don’t worry about being to precise… if your mask is a little off, you probably won’t notice it when it’s played in real time.
3. Make a keyframe for “mask shape” at the first frame of the comp.
4. Move forward 5 or 10 frames and readjust your mask like you did in step 2. Depending on how much the girl moves around on the screen, keyframes might need to be made more often or less often than this.
5. When you’re finished keyframing the “mask shape” across the entire comp, put your text layer between the 2 bike layers.
6. Keyframe the text position to make it move across the screen.PS: I’ve followed layZlite (TechnicalUser) instructions from https://www.tek-tips.com/
Thanks,
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