How to join four files into a 2x2 matrix?

[jivebologna]

I'm running a system with four monitors, and I'm looking for a way to play four MPEG-4 videos, one on each monitor. The issue I keep running into is CPU power, because it has to decode four videos simultaneously.

However, spanning one video across the four screens is a piece of cake. So, how could I take four .mp4 video files and combine them into a single video file consisting of a 2x2 matrix?

Is this possible without having to purchase expensive switching hardware? I'd love to find a piece of software that could do this with simple file inputs.

Thanks!

[mats.hogberg]

You could do it with an AviSynth script - StackHorizontal and StackHorizontal - But your computer would still have to decode 4 files simultaneously. No way to avoid that if you don't want to reencode them into one file.

/Mats

[Scorpion King]

However, spanning one video across the four screens is a piece of cake.

You can do that in Ulead VideoStudio. If you want to actually try this I can give you the specific details, but basically you work in VideoStudio in 2 tracks. In the normal track you place a fullscreen black color slide (for the background), then in the overlay track you place the first of your 4 videos. Size it and place it in one of the 4 corner positions, then export that in a looseless format like Huffyuv codec.

Load that file back in and place it by itself in the normal timeline and drag in your second video into the overlay track and place and size it into then next empty corner, then save this again using looseless Huffyuv. Do this 2 more times and you will have your Black background with 4 running videos (1 in each corner) as you requested. Encode that to whatever you want or leave it in Huffyuv and loose no quality.

Good luck.

[manono]

As Mats said, AviSynth is the way to go:

A=AVISource("C:\Path\To\Video1.avi")
B=AVISource("C:\Path\To\Video2.avi")
C=AVISource("C:\Path\To\Video3.avi")
D=AVISource("C:\Path\To\Video4.avi")
StackVertical(StackHorizontal(A,B),StackHorizontal (C,D))

And use a player that plays AviSynth scripts, such as Media Player Classic.

I don't know how that changes with .mp4 videos, if you maybe have to use DirectShowSource. I've never worked with it. celtic_druid would know.

[jivebologna]

Thanks mats and manono! I had originally intended to re-encode, but I think you both put me on the right track.

However, as you mentioned, .mp4 videos are apparently a bit different. I tried using DirectShowSource, but neither MPC nor VDubMod will render them.

VDubMod returns the following:

Couldn't locate decompressor for format 'YV12' (unknown).
VirtualDub requires a Video for Windows (VFW) compatible codec to decompress video. DirectShow codecs, such as those used by Windows Media Player, are not suitable. Only 'Direct stream copy' is available for this video.

After checking the codecs in GSpot, I see the following:

File Type: 3GPP Media (.3GP) [MP4 compat.]
Mime Type: video/mp4

Does anyone have any ideas?


UPDATE: Nevermind, I figured it out! I used the following script:

A=DirectShowSource("C:\path_to\video1.mp4") 
B=DirectShowSource("C:\path_to\video2.mp4") 
C=DirectShowSource("C:\path_to\video3.mp4") 
D=DirectShowSource("C:\path_to\video4.mp4") 
StackVertical(StackHorizontal(A,B),StackHorizontal(C,D))

And then I reinstalled K-Lite Mega Codec Pack, and made sure to specify Haali's splitter instead of Gabest for MP4 files.

My next task is to span the playback across four screens. I had originally been using a program called MatrixDVD (http://www.xj-spark.com), which works fine for a single file. When I try to open an .avs though, the file plays but none of the spanning features work.