Page 1 of 1

Exporting sequence with alpha channels

Posted: 14 Apr 2012, 20:16
by KathrynWilkins
Hey!

So i'm trying to export a sequence with alpha channels so i can overlay it onto a background. I unchecked background and exported it but when i took it into after effects, the alpha channels weren't working. It was just a big black background...
helllllp.

Re: Exporting sequence with alpha channels

Posted: 14 Apr 2012, 20:27
by Paul Fierlinger
You are not giving enough information. What format is your sequence? What mode? Are you using 24 bits or 32? Only 32bits carries an Alpha channel.

Re: Exporting sequence with alpha channels

Posted: 14 Apr 2012, 20:30
by slowtiger
Always choose RGBA (instead of just RGB) in your export settings, and select a codec which supports alpha, like PNG with Millions+ colours.

Re: Exporting sequence with alpha channels

Posted: 14 Apr 2012, 20:52
by KathrynWilkins
Here's my export settings.

still no alpha channel.:(

Re: Exporting sequence with alpha channels

Posted: 14 Apr 2012, 21:08
by Paul Fierlinger
I tested your settings and they work. I didn't test in AE, but in NLE Vegas. I had to set the Vegas propertied to alpha and that was it. Which version of TVP do you have?

Re: Exporting sequence with alpha channels

Posted: 14 Apr 2012, 21:09
by KathrynWilkins
hmmm
strange
i have TVP 9 Pro

I exported as an mov and a sequence as a psd.

it's not working. :(


ugh, this is slowly stressing me out.

Re: Exporting sequence with alpha channels

Posted: 14 Apr 2012, 21:11
by Paul Fierlinger
I'm on TVP 10.

Re: Exporting sequence with alpha channels

Posted: 14 Apr 2012, 21:13
by ZigOtto
KathrynWilkins wrote: ... ugh, this is slowly stressing me out.
try exporting your sequence in PNG32, it's my favorite format when it goes to export in 32bit.

Re: Exporting sequence with alpha channels

Posted: 14 Apr 2012, 21:14
by Paul Fierlinger
Kathryn, can you use another format besides QT? PNG should work everywhere.

Re: Exporting sequence with alpha channels

Posted: 14 Apr 2012, 21:16
by Mads Juul
Are you sure after effects interpret the alpha channel correct? In afx project window you can right click the footage and set the alpha to multiply.

Re: Exporting sequence with alpha channels

Posted: 14 Apr 2012, 21:23
by KathrynWilkins
Ah, ok so i exported a sequence as a png and THAT reserves the alpha channel.

IS there a way to export a video file with alpha channels and overlay it in aftereffects over a background?

Re: Exporting sequence with alpha channels

Posted: 14 Apr 2012, 22:12
by chatbraque
Yes… the exact same way :D

(in Ae, just put the folder that contains your png's in the "project part" and add it to your comp… you'll get a new overlaying layer)

Re: Exporting sequence with alpha channels

Posted: 14 Apr 2012, 23:23
by KathrynWilkins
ah
that'as what i ended up doing. :)

thanks guys for everything. :)

Re: Exporting sequence with alpha channels

Posted: 16 Apr 2012, 11:22
by Fabrice
One remark though :

The deal with quicktime is inside the codec settings.

Quicktime can not manage the alpha chanel if you compress in some specific formats (like mp4, etc ...)
So if you want to keep the alpha chanel with Quicktime, you have to save uncompressed sequences.

so Kathryn, maybe by using the "config" button and enter in of the quicktime codec config, you might solve the problem.

Re: Exporting sequence with alpha channels

Posted: 17 Apr 2012, 09:45
by Keep Shooting
On AE and QT alpha: exchanging animationfiles with an other company, I used tiff sequences with alpha instead. They told me the AE-version before the latest one has a 'known bug': QT alpha is not recognised.

On QT alpha in TVPAP 10: I would like to import movies with alpha (camera views of a layerd backgrounds that still need further editing) back into another TVPAP project. So I just made some tests with the QT alpha, uncompressed 10 bit 4:2:2 as wel as uncompressed 8 bit 4:2:2 and it is not working. Even choosing 'alpha only' in the import options does not show any alpha at all with the QT's.
AVI (internal) alpha is working fine though!

Kathryn, good chance AVI (internal) works in AE too.
Good luck, Conny