FORUMS: list search recent posts

Matte key (with Alpha) how to make into a mov to change speed

COW Forums : Avid Media Composer

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
dan crouch
Matte key (with Alpha) how to make into a mov to change speed
on Sep 28, 2015 at 2:18:20 pm

Hello All,
I am struggling with an effect.
I have some animated shapes that I am using as backgrounds for an effect sequence to cut between two scenes. They came as two clips with alpha's so I can layer them.
They are great but I would like to speed one of them up in order to use them for a multi layered wipe effect.


I can't speed them up as they are a Matte Key effect and I am told the only way to change the speed is to re import them as QT's.

I have re imported them ignoring the alpha and they come out green.
I have re imported them with 'do not inverrt alpha' andf they come out green. I have basically imported them in every way possible but no luck.I have also tried opening them in QT Player 7 as a sequence, again no luck.

I am using MC8.3 on a mac pro, 3.5 ghz 6-core. OS 10.10.5

Any help would be much appreciated.

Dan.


Return to posts index

John Pale
Re: Matte key (with Alpha) how to make into a mov to change speed
on Sep 28, 2015 at 9:40:40 pm

its a little convoluted, but stay with me...

If you want to change speeds of a matte key, you need to split the alpha channel (Matte) and the fill into separate clips.

Make a sequence.
Edit your imported Matte Key clip into the timeline.
Step into the clip (two arrows at bottom of your timeline). You will see the Matte and the fill as separate clips.
Select the Matte with your red arrow (Overwrite tool in smart tool)
Press Cmd-Alt-C to copy the clip into the source monitor

You can now step out and edit the matte into the timeline on video track 3
Step back in and select the fill clip with the red arrow
Press Cmd-Alt-C to copy the clip into the source monitor

Step out and edit the clip into the timeline on video track 2

Apply a Timewarp to each layer to adjust the speed. You should apply the same speed Timewarp to the fill and matte.

Apply a matte key effect from the effects palette on the clip on video track 3. Note: you may need to invert the key depending on how the matte was created.

Hope this made sense.


Return to posts index

Juris Eksts
Re: Matte key (with Alpha) how to make into a mov to change speed
on Sep 28, 2015 at 9:43:45 pm

Hi Dan, try this:
Step into the clip, you'll have 3 video layers, the bottom one blank (I think). ignore that one. V3 and V2 are the fill layer and the key layer (I'm not in front of the Avid at the moment so can't look to see which is which).
Copy both layers separately to the clipboard, then paste them onto a timeline. (You may have to do a video mixdown). Make the appropriate speed change to both parts equally.
Combine the two new parts onto a timeline, putting the fill onto V2 and the black and white (key) layer onto V3. Put a Matte Key effect onto the clip in V3 and you should be able to key through as before, but with a different speed on the clip.


Return to posts index


Juris Eksts
Re: Matte key (with Alpha) how to make into a mov to change speed
on Sep 28, 2015 at 9:45:06 pm

John got there just before me.
As normal, just in time to be too late!


Return to posts index

dan crouch
Re: Matte key (with Alpha) how to make into a mov to change speed
on Sep 28, 2015 at 9:58:24 pm

Massive thanks to you both, Juris and John.
It works!!!

I am not very good with mattes and found your explnanations really easy to follow.

Very much appreciated.

Dan.


Return to posts index

John Pale
Re: Matte key (with Alpha) how to make into a mov to change speed
on Sep 28, 2015 at 10:24:07 pm

You're welcome.

In 2015 it should not be necessary to have to jump through this many hoops to do something so simple. I love editing on Avid, but its kind of ridiculous.


Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]