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Software live switching/mixing

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Chris McDonald:
Is there any software on the market for live switching of DV sources and videos. I'm thinking something along the lines of the video toaster but cheaper and simpler. I can almost do this now just using vlc. I've been thinking why go out and buy a dedicated video switcher/mixer when the PC got all the hardware needed, I just need some software to pull it together.

If there isn't maybe vlc can be modified to do the job. Thats the the best thing about OSS. Just set it up to read many streams at once and put in a method of selecting or or the other, modifiy the video desktop to do powerpoint overlay. Even pip shouldn't be too hard to setup. Add midi control and pickup a cheap behringer midi control surface. Also you can throw in an extra PCI video card to give a 3rd display for preview...(Most video cards already have a second output)

Mike Noth:
I don't know of any, which isn't to say that they aren't out there.  Though if I understand what you are trying to accomplish correctly, it sounds like it would be analogous to mixing a live band on your Pro Tools rig.  Possible, but widely considered a  bad idea.

I would be very nervous having one machine handling my switch and running the primary graphics and scaling multiple video sources.  And does this configuration allow for a 2nd or 3rd graphics machine?  How do you input them?

Even using the Folsom Screen Pros we will often switch our composite sources on a switcher ahead of the Folsom to avoid locking up the scalers, which is more common than I would prefer.  

I would think what you're trying to do would have too much potential for overtaxing the machine.

My $0.02 after taxes, at whatever the exchange rate is these days.


Chris McDonald:
Basicly I'd like to be able to switch through a few cameras connected via firewire and prerecorded video files and output on my second desktop which feeds projectors. On my primary or 3rd desktop have preview windows for each of the sources. And still have my primary free to type up titles for overlay. Basicly what I do now at home for watching dvd's/xvid and experimenting with my webcam. I just need some software to pull it all together seamlessly. As for having another gfx machine that could be done via tcp/ip, you can even do close to realtime streaming video over gigabit lan these days. Also I see no reason why it couldn't be done via firewire.

As for overtaxing the cpu, modern machines can handle alot of video before getting bogged down. This machine I'm on here can easily decode 4 xvid encoded videos at the same time and not show any signs of slowing down. I'm not looking todo any heavy realtime effects. I've had more problems with the few low end video mixers locking up than I've had with this PC. Now I do know what I'm doing with software, I know how to strip windows xp down so that only the nessary services are running, etc... Also I buy good hardware, server grade power supplies, motherboards, etc... My PC is as stable if not more so that alot of the dedicated products out there.

I'm in a really small market, this kind of production is only called on 2 or 3 times a year so going out and buying dedicated switches and scalers is out of the question. I'm just looking for an alternative to using composite video and bang boxes(The other guy in our market actually uses them).

As for the comparison to protools, I think someone is putting out a console that runs protools plugins and is targeted at live use.  The main reason not to use a PC for mixing a band is the lack of  IO and a control surface designed for live use. Take a look at a mackie TT-24, not much different than a PC, it just has the IO and control surface to do the job.

Mike Noth:
Fair enough, you seem to have it well thought out, and I'll be honest, you've got a better understanding of software than I do.

Running the video cameras firewire didn't occur to me, my work most often involves cameras that are run component into the Folsoms, and I have seen the scalers get funky.

I also see a lot of presenters who have their videos on their computers and shouldn't have.  You sound like you've got better machines then they.

I guess I was playing devil's advocate, and apparently, you've got the things that would concern me thought out.

Good luck finding the application.


Ken Freeman:
So you making a Sony Anycast out of a standard CPU...  Let me know if I am missing something here, but I think a big issue you will have will be latency in the video paths. I can't even  imagine what the processing and sync delays might be. Consider if you will be able to deliver your video and audio in sync.    

As a new client, I can't say that what you are proposing might be something that I'd bet my show on.



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