[ANSWERED] Best way to take in 4 live camera feeds

  • Hey forum, 

    If you were going to take in 4 live camera feeds from 4 camcorders to make use of isadoras 4 live input channels... what would be the best way to do that? Would it really be to just find a way to plug 4 separate capture cards into my computer? Is there a more efficient piece of gear that can accommodate this? To be clear, I'm not looking for a switcher which would provide access to the 4 cams through 1 input. I need 4 individual feeds that I can mix together in real time with izzy utilizing the 4 separate channels. Thanks! 

  • Tech Staff

    @weston I am not aware of any capture device that supports multiple streams.

    One option that I might consider is hardware that tiles your 4 inputs into 1 input so that you only require 1 capture card. Then in Isadora create an user actor that chops down the stream to provide your 4 individual feeds. 

    Hard to say what would be most efficient, but I feel chopping video on the GPU is pretty light weight.

    We're setting up 4 capture devices might be more difficult.

  • Tech Staff


    Hi there @Weston

    Personally, I would use a Desktop PC with a Decklink card. See https://www.blackmagicdesign.c... for more information. For the situation that you sketched above, a Decklink Dou 2 would do the job just fine. Using some Blackmagic Mini converters to convert your HDMI signal (since you talked about Camera feeds, they likely have Mini HDMI / HDMI output) to SDI.

    But like always with these types of stuff, test test test!

  • I'm pretty sure that Matrox does a capture card with 4 inputs...




  • Tech Staff

    right..  I'm so laptop centered..  I didn't even consider a desktop, but yes a desktop is likely the best route.

  • For a more portable set-up, I built a 4- channel HDMI capture box using a Magewell quad HDMI card and a Sonet Thunderbolt 3 enclosure

    The Magewell card I have is an older model that was cheaper than the current model


    There are other cards that can work as well, such as this for $500


    The Sonet Enclosure seem to be the most compact and costs $250


    Alternatively, you can get a  4k USB capture adapter and a 4k multi-view box for $200. 

    This USB Magewell dongle captures 4k 60 USB


    This multi-viewer takes 4x 1080 inputs and arranges them into a 2x2 split-screen output at 4k 30. I don't have a 4k capture card but the box I have works fine with my 4k monitor.


  • @weston I have a Blackmagic duo 2, it can do 4 3g sdi inputs simultaneously and works perfectly with Isadora. Make sure you put it in a proper pcie 8x slot , many motherboards share resources so even though you may have a slot marked 8x free it might not operate at 8x when you use other devices as they share bandwidth. Apart from tricky motherboard specs it works perfectly.

  • @weston

    Hi, if you don't need the 4 flux at the same time , or just crossfade 2 of them, Atem Mini would work for that, you can remote control it with ATEM osc to switch cam, 
    curious to have your feedback on your choice ! 

  • Tech Staff


    Hi there ! I marked this question as answered. If you still have any questions, feel free to reply here and we will help you out :)