How To code ALPHA channel in your Video-Editing sofware

[Ruud]

What about, editing video, cut out the subject/object where it is all about and leave the background ALPHA instead of black white or so on...

That would be great in Resolume, because the A At Da Li modes can never be of such good quality as an alpha channel inside your video sample. (like .png in picture files)

Question is:

Which video codec is best capable to handle alpha channel, and is also capable for live performance!

I have done some research,

-I suppose quicktime .mov can include alpha layer, not sure about that!
-Ligos Indeo 5.11 has an Alpha channel option when coding
-there is something like the Animation codec :S dunno what that is but it says it has huge amounts of data rates
-Targa sequence, even bigger filesizes

2nd Question,

How to change a black or white background (blue green or whatever) in to an alpha layer with 0% opacity!!!

Am I in the right direction? Can anyone help me out, thanks!

CheerS!

[bart]

we have done some tests with aftereffects but it seems impossible to render an avi with an alpha channel with the indeo 5.1 codec. It is possible when rendering a quicktime with the indeo codec bet the alpha channel that is rendered seems to be only 1 bit. (so either transparant or not and nothing in between.

if anyone finds a sollution to render video,s with a propper codec with a normal alpa channel we will build-in support for it in resolume.

;-D

[levon]

ill have a play round, and see if i can find anything that can.

[Anonymous]

very intresting if it would be possible! I'm gonna do some testing with the above listed codecs too,

every night i dream about alpha channels ;)

that would be just wonderful, great! I was reading on vjforums that says some other VJ software would be able to handle alpha layers, in combination with raid-0 drivers and big uncompressed video samples 32 bit targa for example and 20 x amount of filesize/datarate.

bart> q:"It is possible when rendering a quicktime with the indeo codec but the alpha channel that is rendered seems to be only 1 bit. "

ok so it is only 1 bit, can't you make resolume handle the alpha 0% or 100% so there is a possibility to make video samples semi-trasparant?



cheers

[Anonymous]

I love Alpha

[Ruud]

I'm sorry forgot to login, above 2 posts are not Anonymous anymore.

I figured out there are many was to implant Alpha channels in non Alpha-channel footage. Still dreaming!

bye for now

[levon]

i found quicktime TGA keeps the alpha inside the movie, and it actualy already works in resolume, but only using it as a 1bit channel.

[Ruud]

As I'm reading about Alpha channels,

8 bit Alpha channel should be enough, because it can have 256 different vallues of 'greys'.
This links tells a little about Alpha channels and the difference between 1bit and 8bit.

Maybe not new to you guys, but it is new to me.

http://www.planetquake.com/polycount/re ... ency.shtml

So let's see if there's an codec that can include an 8 bit alpha channel and is suitable for resolume too! I'm really enthousiast about this new stuff because in my opinion it opens loads of possibility's when preparing footage!

Cheers

[Ruud]

guess i found something 8 bit!!

FRWA Forward Motion JPEG with alpha channel SoftLab-Nsk A version of motion JPEG as used in the Forward project from SoftLab-Nsk. This format also includes an 8-bit alpha channel per image.




And maybe even better!!!

http://www.bitjazz.com/ // Special Codec for Visaul Jockeys!

Cheers!



[Edited on 24-2-2005 by Ruud]

[levon]

what i ment by

i found quicktime TGA keeps the alpha inside the movie, and it actualy already works in resolume, but only using it as a 1bit channel.

is that it only suports 1 bit in resolume atm, the format does suport an 8bit alpha channel.