installation with two matrox TripleHead2Go dp: set-up hints?

    Oct 24 2014 | 2:05 pm
    Hi all, I'm developing a Max patcher to handle a 6 channels video installation (6chx720x576). The available hardware will be a Macbook Pro (last generation, best graphic card) and two matrox TripleHead2Go DP. I searched on the web and this forum but I found not all the answers about the set-up. Generally, how did you experience this combination? Something special required (excluding needed adapters)? Is the Macbook pro, for example, able to power all the two Matrox trough usb ports or we need a powered usb hub? In short, any hint really appreciated! :)

    • Oct 24 2014 | 3:18 pm
      you can just use a ipad charger to power each matrox DP edition. Plug in both, use the editor and set them up as usual, should be good to go. Only problem is not sure how you'll use two of them, I use a thunderbolt to DVI adapter, but thats all I have, do you have two video out with the new macbook pro ? If so then there shouldn't be a problem.
    • Oct 24 2014 | 5:08 pm
      Hi Andro,
      thanks a lot for the quick reply. I'm not still have the new macbook but I'm working with a mb pro late 2013 and it has 2 thunderbolt ports, as the last model. So yes, it has two video outs.
    • Oct 24 2014 | 5:28 pm
      I've been using a Macbook Pro (late 2011 model) with one Matrox TripleHead2Go DP that's run via a MAX patch in a permanent public art installation since early 2012. Two issues:
      1) I've had trouble with auto-start-up each day -- by the time the USB-powered Matrox is up and running, the Mac has already looked for and not found it, so it ends up not recognizing the external monitors. Partial Solution: don't power the Matrox from the laptop; use external power source (USB hub or something) so it gets continuous power. Also, make sure the Matrox firmware is up to date. Even this didn't solve it 100%; even with external power, the Matrox sometimes goes "down" or to sleep or something, and is not recognized by the Mac when it re-starts each day.
      2) This installation has been running daily from 7am until 5pm, 5 days a week since early 2012. I've had to replace the Macbook Pro logic board twice in each laptop (there are two separate, identical installations, so two Macbooks, two Matrox, two sets of 3 monitors). Luckily these have all been under extended Applecare warranty so far, but it just ran out. At first, Mac Genius Bar employees told me I'm not doing anything extreme with the Macbook Pro, but then after the second set of logic board failures, they said that running video constantly like this is one of the most taxing things you can do. We'll see...
    • Oct 24 2014 | 5:58 pm
      You should be able to run the 2 tripleheads on your MacBook Pro Retina; I've seen some tests running in this config. For your macbook, output 6*720 or 2*2160 pixels wide is more or less the same.
      And yes, it will be better if you use an external USB adapter :-)
    • Nov 02 2014 | 7:28 pm
      Thanks to everybody! I would need another little help. I completed the developing, placing the six videos inside a unique jit.window trough Everything works but I'm not able to fill completely the window (4320 x 576). In other words, I don't understand how to find the six positions that exactly place the videos into the big window. I don't yet have at my disposal the two TripleHead2Go, so I'm trying in a virtual way… Thanks for any help.
    • Nov 03 2014 | 1:32 pm
      I'm not sure to understand well your question.
      First, you will not have ONE output of 4320 x 576 pixels, but TWO outputs of 2160 x 720 pixels, as you use 2 matrox. Each matrox is seen as a different screen. So, your computer will see 2 differents screens.
      I think this thread will help you to fit your video using jit.window object and output them with the TripleHead.
    • Nov 03 2014 | 3:40 pm
      Thanks Bart. Unfortunately the matrox will be at my disposal only close to the date of the show, so I'm tryin' to plan everything I can. Thanks for the link, I've checked it some time ago, but my problem is how to precisely fit the videos inside the jit.window. So, I create a jit.window of 2160x576 and I place three videos (each being 720x576) inside with the position attribute. I need to scale jit.window to about 1.04 to have no gap, otherwise the window is too big. But 720x3=2160, so I clearly fail to see something… All this not directly related to the matrox, but I'm trying' to predict problems… And again thank you to make me notice I'll have to handle two screens.
    • Nov 03 2014 | 4:12 pm
      You don't need separate windows for the 2 matrox's. 1 window can span as many display outputs as you like.
      What I do is create 1 window that covers the 4 projectors that I use. 3 on a triplehead and 1 on an extra output of my graphics card. In that window i position 4 which I render tejh contents that I want to have on each screen to. No messing with window borders etc. Just positioning and scaling the videoplanes accordingly.
      I quickly ripped this bit out of my project. It creates the window and videoplanes for 4 x 1280x800 projectors. The window starts at 1920x0 because I have a 1920x1080 monitor connected to the system too, which displays my control patch. The projectors window is placed to the right of that in display preferences. This should get you started in the right direction.
    • Nov 03 2014 | 7:19 pm
      many thanks DTR.
    • Nov 04 2014 | 8:56 am
      Matteo, if you have to "scale" your video at about 1.04, it could come from your video file. Are you working in PAL ?
      If so, I know, but I don't remember exactly, that the shape of a pixel is not "square" but a little bit "rectangular". The ratio transformation is about 1.09 in PAL if you want to convert it to read it properly on a computer, for exemple.
      I don't know how Max/MSP reads the PAL video with these ratio because I never used PAL video in a project, but I'm quite sure that it does not "convert" the pixel size if you don't ask for it.
      Does that make sense in your project ?
    • Nov 04 2014 | 10:32 am
      Hi Bart, never thought about that in Jitter… Yes, the videos are PAL (720x576, 25fps). Your observation makes sense! I'll try to investigate this matter, but I didn't find anything relevant in the forum.
      Thank you again.
    • Nov 04 2014 | 1:50 pm
      Let us know if you find the solution :-) I'm curious.
    • Nov 04 2014 | 6:27 pm
      At the end I've set up the jit.videoplane @transform_reset to 2, rescaling and replacing appropriately the six windows. Thus I can resize the main window and the content is automatically adjusted. Eventually, the scale value is 0.168. The method was totally empiric… :-) but I suppose some formula exists for that.