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Television Media

Video Multiplexing on Large Screens? 29

videoPIP asks: "I recently finished putting together my home theater (including a projector). As I sit there and watch stuff on the big screen, I remember a time back in college where my housemates and I would have 2 or 3 TVs crammed into the entertainment center, one usually having a football game on and the other playing movies or for video games. This got me to thinking - I know that, for CCTV security systems, they have 4 screens visible at a time, but they are usually black and white (like at Best Buy). I've looked on Google for these, and there are all sorts of configurations (4/9/16 channels), (simplex/duplex,triplex). I was wondering if anyone has married one of these multiplexers with a projector, or even a very large TV to get the ultimate Picture-in-Picture experience?"
"I guess the things that are important are:

1. 16 channels and the ability to combine multiple screen areas to have 'larger' screens.
2. Ability to convert input signals to BNC jacks (which is most boxes I see) or have 'normal' inputs: composite/svideo/component(doubt that last one).
3. Likewise, convertible or normal outputs.
4. Comes with remote control and on-screen-display for setup(don't want to mess with a serial interface).
5. Audio inputs/outputs would be nice, otherwise I would need a similar 16-to 1 audio switcher with remote.

I don't care about alarms/video signal loss/motion capture, so those features I could take or leave.

Another related question is how to provide 10+ cable/satellite inputs that are controllable with a single remote without having to have a freakin' rack of VCRs or other boxes."
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Video Multiplexing on Large Screens?

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  • I"m sure you could get one of those bad-ass programmable LCD remotes and set them up for multiple recievers.
  • VJ Software (Score:3, Interesting)

    by dave1212 ( 652688 ) on Tuesday November 29, 2005 @09:51PM (#14143565) Homepage
    You will also need a hardware solution, but some software for video that would be a good start for others perhaps would be one of these apps (if you're using OS X or winxp):

    Both written by a VJ, Kiritan Flux:

    mietzplayer v.1.5 [] - videoplayer, that plays two movies synchronously on two monitors. Mac OS X and Windows XP

    jallajalla v.1.0 []- videoplayer for use on two or more computers to frame-synchronously play video files - master and slaves, network required - Mac OS X and Windows XP

    Going to use these for my band's onstage video stuff. I don't know how many channels of video they'll do, but on the audio side, you probably want something like a M-Audio Firewire 1814 [] or something.

    (from the spec page: 'The FireWire 18/14 is an 18-in, 14-out audio interface complete with ADAT Lightpipe for multi-channel communication with other digital devices. It features 8 x 4 analog I/O at up to 24-bit/96kHz, and boasts 192kHz on the first two inputs and all four outputs. Channels 1 and 2 also include high-quality microphone/instrument preamps. S/PDIF optical digital I/O provides 2-channel PCM, as well as pass-through of surround-encoded AC-3 and DTS material. Flexible internal mixing allows input and output routing, including an aux bus for effects send or monitor mix. A front-panel momentary switch allows DJ-style headphone auditioning between two assignable sources. Other features include two headphone amplifiers, assignable level controller, S/PDIF coaxial/optical digital I/O, 1 x 1 MIDI I/O, and BNC word clock connectors for synchronization to other digital devices.')
    • Re:VJ Software (Score:5, Informative)

      by CommanderData ( 782739 ) * <kevinhi&yahoo,com> on Tuesday November 29, 2005 @10:28PM (#14143723)
      Your linked items are interesting but I think you may have misunderstood his request- he doesn't want to have multiple monitors/TVs synchronized and showing the same video. What he wants is to use one large screen - projection, HDTV and display 4, 9, or 16 individual video sources all on one image (like the black and white CCTV security video footage mentioned).

      With that said, I'd suggest a high-end dual core desktop PC with 3 or 4 TV tuner cards installed. Connect this to your HDTV (1920x1080 preferred!) with a DVI cable and enjoy. Of course it may require writing custom software to display those all at once, or alternating Xvid/H.264 files for some of the squares. I'm actually working on a scaled down version of this for my next house. I want to watch TV/video and have other things overlay on top- Weather forecast at a button press, caller id when the phone rings, Video PiP of the front door when someone rings the bell, etc. You know, the typical home of the future junk. I really just want to try for the hell of it, I may never get it all working but I'll learn a lot along the way...
      • Re:VJ Software (Score:2, Interesting)

        by doorbender ( 146144 )
        The lower end tuner cards I have been working with use the pc's sound input and therefore are a hassle to setup multiple cards in a single linux machine. (I've tryed a dual tuner mythtv box) WinXP wasn't able to use them both at all. It seemed to have trouble keeping them straight.

        A remote wouldn't be able to distinguish between them if they all use the same signals. Some people think this is a big deal. I would just use a wirelessmouse and/or keyboard.

        I share the dream. Am in the midst of building a M
    • I have an 1814 and would not recommend it. It works, but is not the best. I bought it for all of those features that were mentioned, but overall I wish I bought something cheaper. It has gone down 100$ since I bought it though.

      The device does not have a software reset, and it took me about a month to figure out that it needs to be power cycled if you want to change the sample rate. The directions read like a voodoo manual. It talks about doing things like putting your computer to sleep and waking it up
  • When the DMD first came out, Larry Hornbeck, the inventor talked about applications like that at a presentation I saw in Houston, but I haven't heard of anything about it since.
  • So you basically want the Marty McFly's TV from Back to the Future, part II?

    Ask him, I'm sure he'll be glad to share his info : )

    (I am serious actually, they used something like that in the movie, so I'm sure it's possible. Doesn't look that hightech, maybe back int he 90's it was different ...)
  • get an analog one (Score:3, Informative)

    by Naikrovek ( 667 ) <jjohnson.psg@com> on Tuesday November 29, 2005 @11:25PM (#14144020)
    security companies sell them.

    buy an analog one, not digitall, unless it is fast enough to update every image at your desired framerate. digital multiplexors that i've seen usually only update each image maybe 4-8 times per second. digital is cheaper, but you don't get what you want with digital.

    that was about 7 years ago though, i don't know what they're capable of now.
  • What you want is a video mixer, like you might find at a TV station. Problem is, they're not cheap.

    here's a 4 channel [] for about 1100$ US. And 8 channels for 2600$ US. []
    I don't know anything about this model, or really anything else. I suspect if you find something that does what you want, it will be far outside your budget.
    • Edirol (now part of the Roland Group) makes decent equipment. Unfortunately, video switchers typically take multiple inputs and will only display one (or two, if in the middle of a wipe/dissolve/whatnot) on the output.

      Same goes for the Sony unit. That is meant for conference rooms; lots of mic/audio inputs, only a handful of video inputs, and it doesn't mention multiplexing. At best it's going to do the same as a typical video switcher will.

      While this particular product may not provide the highest
      • Pelco makes pretty nice stuff. I'm not sure that a security solution is going to be what he's after. Unless combined with a keyboard or a serial connection, it would be too much of a pain to switch modes.
        My company distributes Pelco, a MX4009CD - 9 input NTSC color multiplexer is going to run you about 1300$.
        But as long as we're turning his living room into a CCTV paradise, we can put together a nice digital package. Unlimited video inputs, all digitized. They all get sent to a DVR server, recorded if
  • Get yourself 4x 4-channel security system PCI cards [] (or 2x 8-ch, if they support high enough framerates, or a 16-ch..., or any combination...) and put them in a powerful computer with a good graphics card. All you need to do is have sixteen instances of media players (tiled across the screen) running simultaneously.
    Security systems even use BNC by default!
  • Ask a NOC (Score:5, Insightful)

    by Midnight Warrior ( 32619 ) on Wednesday November 30, 2005 @12:40AM (#14144369) Homepage

    Network Operations Centers use these kinds of setups all the time (except for the audio). This is going to seem like a plug, but I've been researching this for work. One that I've found so far is the MediaWall 2000. You can control it via serial or Ethernet, so the presumption is that you might have a customzed/handheld interface developed. They also have other, related products [].

    You say that you want an on-screen display with remote, but most configurations this complex aren't being built for you, they are going to emergency response centers and such where there is a person in the hot seat watching various view points. It needs to be quick, easy, and customized (label the inputs for example and put the most used at the front of the list). This quickly points to an embedded solution. Talk to a sales rep and find out what your choices are. I'm going to end up doing the same in a few weeks.

    I'm quite sure this isn't the only vendor for this type of product, but I did search for a while and came up somewhat cold. Talk to a local audio/video specialist for help, although they probably will want a piece of the action.

    As for the audio - you and I both know you need a mixing board, even a simplistic 16-channel version. You said that you want picture within a picture, but these really complex solutions might mean you want four pictures on screen and to have each feed come from one of four speakers, presumably in pseudo-surround mode. A mixer could work in two modes - aux1-aux4 feed amps that drive four speakers around you. The main setup could also just drive your fronts, although you'll lose and 6.1 sound you might be running.

    In the end, I think you're overdoing it. You probably can't process more than two pictures at a time, much less 16, unless you're watching sports. You want to avoid a "bunch of VCRs" but yet you want 16 channels of individually tunable inputs ala tuners. I don't get it. You won't be able to maintain surround sound at 6.1 and still have multiple audio feeds. Since you want so much versatility, I assume you're one of those rich boys that will gladly plunk out US$3000 every couple of years for a new display. Then it may also be safe to assume you would pay someone US$1000 to design such a system to your specifications. People do this for a living so as the yellow pages in your area for help with Audio-Visual-Consultants.

    Other interesting finds:

    • Zektor [] audio/video switches. 4 channels, but HD and digital audio supported
    • Crestron [] the maker of RS-232 control units.
    • AMX [] - a competitor to Crestron.
    • Tekron Communication Systems [] - okay, these guys are for broadcasters, but maybe you really want to get weird.
    • AVR 8000 [] - a security video switcher
    • Barebones [] for the cheapskate in all of us
  • If you get a 1080i-native-capable projector, you'll wind up with a gorgeous result. It may not have the total pixel resolution of your 4X4-multiplexed system, but it will lack the gaps between the displays and you'll be able to emplace the picture-in-pictures via software, with (depending on your system's horsepower) the ability to split the window up into as many boxes as you want.
  • ADHD type problems already. I find that when I'm trying to do something else while watching video, I get less out of both activities... e.g. the email I'm writing is distracted *and* I'm missing some of the dialogue from the CSI (or whatever).
  • 1. Get 16 external TV tuners. I personally have one AVerMedia UltraTV USB 300 and it is small and does not get hot, so 16 should be fine
    when put side by side. Any brand will do.
    2. Get 4 pci cards with 4 usb ports each, and a mobo with 4 or more
    pci slots.
    3. Now just take the feeds and switch and crop and whatever in
    software. There are programmable usb remote controls. A USB TV tuner
    should be about $50 on eBay, a barebones PC on eBay is about $100,
    PCI cards are like $5 each, a USB remote control will be about
    • Re:Easy (Score:1, Redundant)

      Actually, using the prices you quoted but with correct math, the price is $940. But I'm pretty sure that a computer capable of decoding 16 independent USB video streams will cost a bit more than $100. I'd be thinking more along the lines of an Athlon X2 or one of Apple's multiproc beasts. Even then I wouldn't be too certain that the PCI bus could hold up.
      • Yeah, my bad. Long day at work (just came
        home now so not much more coherent).
        Anways, my first version of the post
        was an off-the-top-of-my head estimate
        of $5000, then I did som eBay'ing and
        wrote that post and was like, "wow
        that's cheap" :) Should have thought a
        bit before hitting submit.
        In any case, for something this industrial
        strength, I figure anything below $10K
        is cheap, and the setup is pretty easy.
        And most likely he doesn't need all
        16 channels at once, just to select from
        so PCI bus should be fine. If no
  • There was a story a while back about Video Whale []

    This is really the opposite of what the poster wants, one source on many screens rather than one screen with many sources but GStreamer would probably be a good place to start if you wanted to write something to do this.
  • Looking at this from an engineering standpoint you have two problems to solve, and neither of them are easy:

    1) You need to lock frame sync and line sync on all of your sources of video. If the frame sync is not locked then you will have a number of windows with 'rolling' pictures, if the line sync is not locked then a number of pictures will be unreadable.

    2) You need to switch between your image sources cleanly and VERY quickly. At 800x600 a single line is scanned in 0.000030414 seconds (1/32880 Hz). Divi
  • Then you need some infrared cameras and wireless headphones. The cameras track the headphones and the eyes of the headphone wearer. Depending on where the user is looking the audio sources are amplified or reduced so they can still hear the noise from other images, but the one they are looking at is clear.

    Then get rid of the headphones and use one of those ultrasonic speakers that becomes audible only around their head.

  • you're in for a wallet shock...

    what you are looking for is manufactured by pro-video hardware companies.
    the 2 items that come to mind right away are :

    the Leitch Neo SuiteView []


    the Miranda Kaleido K2 []

    both are over the 30K USD mark...
  • Such as these ADHDTV [] sets. Photo here [].
  • Keep in mind that you are loosing resolution with the multiplexing.

    A projector may have some fabulous resolution but you are only getting a portion of that for your multiplexed content.

    If you go with a analog solution, and can genloc all your sources, then your probably stuck in TV resolution anyway. So, XBOX in the corner of a 520*480 screen. Hmm Not my desire.

    If you could use a capture solution for each incoming source, and then digitally mix/multiplex them onto a 1024*768 solution for single projec

If a thing's worth having, it's worth cheating for. -- W.C. Fields