Alpha Channel

[samsc]

you want to do it properly?
so that it looks 'professional'?

where did your source footage come from?
what codec does it use?
r

[Portal]

you want to do it properly?
so that it looks 'professional'?

where did your source footage come from?
what codec does it use?
r

I would love to be able to have a moving background ( i.e any stock catalyst loop or anything else i have made. i usually use photo jpeg ) and then fly a jpg over the top of it except make the " black " back ground disapear. The problem is that anything that is not the opposite of black ( i.e . White ) seems to become partially transparent as well. I do want it to look like somethign i would see in a well edited video.
I use this a lot in corporate situation where I want to be able to put there graphic or logo over my back grounds.

Hope this helps. Any Ideas ?

Cameron

[tharding]

Use PNG files. Essentially they are the 16bit equivalent of GIF which supports transparency. Just make sure you have a transparent background in Photoshop and save as PNG.

No need to use transparent blacks. Catalyst will see the transparency automatically.

Cheers

Toby

[samsc]

yes.

if you have a static foreground with moving background

use png or tiff files created in photoshop.

use layers to create transparency.

---

if you want a moving foreground thats a whole different can of worms.
you need to have some real experience doing this in post-production - before beginning to do this type of thing.
keying ( green screen or whatever ) - is not as simple as it first appears - particularily with digital video sources.

[Spam Butterfly]

Native photoshop format (.psd) also supports alpha channels.

Hugh

[samsc]

Native photoshop format (.psd) also supports alpha channels.

Hugh

you cant use native photoshop files - the alpha channel is pre-multiplied - or the wrong way round for me.
also layered photoshop files include a hidden composite layer - that overrides any alpha information when imported into catalyst.

----

you need to use png and tiff.
this was explained in some detail many moons ago.
search for png in catvx

[Portal]

Thanks Guys this is perfect.

Cameron