Split Screen at 45 Degree Angle

sms wrote on 9/4/2002, 1:46 AM
I want to split the screen at a 45 degree angle (corner to corner). I want video A to play in the upper triangle of the screen and video B to play in the lower triangle of the screen. I have played with the cookie cutter filter and that just doesn't get a perfect 45 degree split. I tried track motion but couldn't get a 45 degree angle and no luck with event pan and crop either. Any other ideas on how to split the screen into a 45 degree angle so two videos can play at the same time?

I had partial luck by creating a black and white color gradient at a 45 degree angle and then applied the chromokey filter and keyed out the white. I then placed my video beneath the color gradient on a new track. This gave me my perfect 45 degree split with my video showing through in the upper triangle but couldn't figure out how to display a different video in the "black" portion of the screen.

Comments

pumpford wrote on 9/4/2002, 5:04 AM
Many times the key to success in something like this is to not attempt to do it in one complete sequence.

First, Chroma is not the best option to use with black and white, Luma is. Luma is the black and white (dark to light) portion of the video image. Chroma is the color. Alpha mattes are the cleanest for masks. Alpha can be assigned to any color or even to black or white. The necessary bitmaps can be created in a photo editing program such as Photoshop.

But, until you figure all that out, here's how you should do it.

Forget trying to do it in one full sweep. I created a bitmap split from corner to corner using the gradient technique you described with only one step between the colors. I put black in one half and pure blue (R-0, G-0 B-255) in the other.

I first used blue screen to create the first clip and rendered it out to a new file. I then had my video in one half with pure black in the other. I placed this clip over the other clip and used LumaKey to get rid of the black, and then rendered out the new clip.

If you want to see the result cut and paste this link into your browser:
http://www.digitalvideosolutions.com/download/Split.avi

I used the Microsoft MPEG-4 Version 2 codec at 14.98fps, and the file size is just over 1MB. I did note that when I played it back from the web I got a message that the codec was not properly signed. Go figure, it was installed with the Windows Media Encoder package straight from Microsoft!

Larry Johnson
Digital Video Solutions - http://www.digitalvideosolutions.com
Tyler.Durden wrote on 9/4/2002, 6:57 AM
Hi sms, pumpford,

A splitscreen may be easily created using the gradient background generator as a mask.

Track 1: B+W grad (circle, angle, box, etc.)
Track 2: A-roll Video
Track 3: B-roll Video

Simply click the "make compositing child" button at the far left of the Track 2 Header, to create a composite of the two video tracks.

The gradient can be keframed to move and sharpen/soften over time.

(The above should provide more straightforward and better looking results than chromakey.)

HTH, MPH
pumpford wrote on 9/4/2002, 7:29 AM
Though the method of creating a gradient is fine for a transitional type effect, the user wasn't attempting to the split screen effect over time - as I understand he wanted to simply split it and have two different videos at the same time. The type of effect you are describing is little different than that which can be achieved using packages such as Video SpiceRack.

Larry Johnson - Digital Video Solutions - http://www.digitalvideosolutions.com
Tyler.Durden wrote on 9/4/2002, 9:38 AM
Hi sms,

Spice effects are great, but not really needed for this...

Using Vegas to do split-screen (static or animated) is so easy and fun I figured I'd write it up over breakfast:

http://www.martyhedler.com/homepage/Vegas_Tutorials.html

Click on "Split-Screen" to get a peek at the technique I suggested.

HTH, MPH
Former user wrote on 9/4/2002, 9:53 AM
Nice page Marty and some good tutoritals. thanks for your work.

Dave T2
sms wrote on 9/4/2002, 11:26 AM
Pumpford,

Thanks for the reply. Your interpretation of my question was correct. I was heading in the direction you suggested but was curious if there was a more elegant way to achieve the effect without having to render in between. Thanks for your input.

Marty,

Thanks for pointing me to your tutorial. I will experiment with the technique you described. Thanks.