To Johnny Roy, PI 3.0 question

jeff_12_7 wrote on 1/17/2005, 9:24 AM

Johnny Roy wrote:

"This is not a plug-in but Particle Illusion will do the same as a standalone application. It can composite with your video source or you can output the effects with alpha channel to composite in Vegas. I have the SE version and it works great. I usually output TGA stills with alpha and then have Vegas bring it in as an image sequence. I’ve found this gives the best quality for alpha keying. The best part is, it renders in real-time if you have a good OpenGL compatible graphics card."

Johnny, (or anyone else please)
Thanks for the tips on using Particle Illusion... I downloaded the demo and it seems like there is a lot of neat effects to choose from. I am having difficulty creating any quality clips. Here's what I am doing:

In PI 3.0 I am dragging "Start Trail 2" into the main middle window. The duration is from 1-120. I create a green background in that window so I can key it out in Vegas. I save it to TGA and check "save alpha".

I import 1-120 into Vegas and put a picture below it and use chroma key...

Is this how I do it? Any further explanation would greatly appreciated!

Thanks,
Jeff

Comments

Liam_Vegas wrote on 1/17/2005, 9:36 AM

I;m not a PI user... but I can definitely say that adding the green background in PI is not the way to do it. You need to have a transparent background in PI (it will probably still appear to be black anyway). Then when you load the resulting TGA's into Vegas the alpha (transparent background) will already be there with no need for you to do any chroma keying.

apit34356 wrote on 1/17/2005, 9:53 AM

Be careful about using black for fhe apha channel. Since shading is used for 3d effects, the rendered images will take a hit. Choose any color that is not used in your rendering for your alpha channel.

Liam_Vegas wrote on 1/17/2005, 10:31 AM

I'm not suggesting you should use black for the alpha channel. It's just that in many cases unless you choose otherwise - black will be the default background "image" - however that is in fact actually a transparent background and when rendered out <properly> (as TGA/PNG or Uncompresed AVI with alpha channel) will become a transparent background. This is actually the same way that Vegas works.

jeff_12_7 wrote on 1/17/2005, 11:45 AM

Thanks.

Yes, putting the green background in the Particle Illusion 3 wasn't the way to go. Instead of saving to TGA, I saved to PNG and got the transparency I wanted. The last thing I need to figure out is how to get these to the Vegas timeline without each frame (all 120 of them) being 3 seconds a piece.

I did render the track to avi but when I do that I lose my transparency...so I want to take one PNG file and make it exactly one frame in length. (4 seconds = ~120 frames). Any ideas?

Thanks,
Jeff

apit34356 wrote on 1/17/2005, 12:21 PM

choose uncompress avi with alpha channel. you can import the png seq files as a single file in vegas. check the help file in vegas for quick examples or use the forum search. there are many previous discussions how to do this with examples.

Liam_Vegas wrote on 1/17/2005, 12:25 PM

To activate the alpha channel in Vegas for that AVI file you must set the properties of the clip to Alpha-Staright (or sometime Alpha-Dirty). Right click the clip (in the media pool) and select Properties.. you'll see the option listed there.

If you are importing an Image sequence (for such a short segment - this is likely a good way to go anyway)... just specify the frame rate is 29.997 and your 120 frames will be loaded in sequence correctly on the timeline.