9 video splitscreen

A simple way to combine multiple video’s on one screen.
We looked around for simple tools to make a splitscreen in multiple parts, not just two, but with more fragments, so that the final result would be a checkerboard with small video’s. Unexpectedly it was hard to find. Finally, turned out it is a job of 5 minutes for our beloved Cinelerra.

I’ll do my best explaining it as short as possible, but it will probably take you longer to read the description below than the actual work of doing it, sorry.

We wanted to make a video with 9 small films combined. In the screenshots you see distorted images, this is due to the characteristics of the source material: they are video surveillance images, that are transmitted through a wireless connection, which we intercepted with a hand held monitor.

First we have to make a project with the correct size.
This size should be 9 times the format of your source films.
In this case I made a project W x H : 1920 x 1440
(so ratio is 4:3, or click ‘auto’)

* Open Cinelerra
* Settings > Format, set Width and Height to 1920 x 1440.

To fit in a project sized 1920 X 1440, my source material had to be resized to 640 x 480. When imported in a square of 3 x 3 films, the combined size corresponds with my project.

Mencoder resizes the videos and converts them to Mjpeg for smooth handling in Cinelerra with the following line:

mencoder -oac pcm -ovc lavc -lavcopts vcodec=mjpeg:vbitrate=4000 -vf scale=640:480 -o output.avi input.avi

Import the videos in a Cinelerra timeline
* File > Load files > choose path to video’s.

Make 9 video tracks:
* Video > Add track (repeat 9 times)

If you have sound, also make the appropriate amount of Sound layers.
We had nine, so:
* Audio > Add track (repeat)

From the media bin, introduce all nine video’s to the nine different timeline’s.
I trust you know how to do this, if not check the Cinelerra manual.

Oh, yes instead of 9 different files, I used the same file at different startingpoints. My timeline looks like this:

* Right click in every layer and select ‘Match output size’:

This enlarges the layer from the size of the imported video to the size of the desired output.
When you look in the compositor window you will see that your films are way smaller than your canvas, which is what you want because you want to fit 9 of them in.

Now that all your video’s are on a timeline, place the small video’s.
In the compositor window:
* Select ‘adjust camera automation’
(round button, hover mouse over to see yellow square with description)
* Then click ‘Show tool info’ which is the question mark button

A small window pops up (as image above)
In this window you can adjust the position of every small video on the canvas.

Some preset alignments are indicated by the red striped buttons in the info window.
The top three align your video horizontically: left, middle, right
The bottom buttons align vertically: top, middle, bottom.
* For every film, choose a preset position.
Click one of the top three, and one of the bottom row.
This will place video 1 top left, video 2 top middle, video 3 top right etcetera.

You should obtain a seamless square of 9 vids.

5, 6, 7 …
Which you now can render to your preferred file format.

The final result looks something like this (sorry bad quality):

If you managed to get this far I assume you worked with Cinelerra before.
If you have questions about Cinelerra, I suggest that you check the Cinelerra for Grandma manual, or else the Heroine warrior one or the Cinelerra Community Version manual.

Posted on: Wednesday, December 29, 2010 by: in category: Editing software, Manuals, News, Problems and solutions