Dual Thunderbolt Blackmagic Intensity Shuttles between MacOS and LZX Visual Cortex for concurrent video playback and capture

The question of how to playback and capture video using Blackmagic Intensity Shuttles comes up regularly so I’m documenting a working solution for future reference. Most recently the question was asked in this thread: Blackmagic intesity shuttle output to visual cortex?

For playback of video from Mac, Syphon is what holds everything together for me. My current workflow is this:

Signal Culture Frame Buffer (version 4.0) to open and playback video file (This can be done numerous ways, with any app that can output to Syphon [Max/MSP/Jitter, etc], Frame Buffer is just what I happened to be using at this time).

  • Select video file for playback by clicking on Video File and navigating to your existing video file
  • Select Settings, Video Input/Output:

Under LIVE VIDEO OUTPUTS turn on Syphon Output:


Black Syphon (version 4):

  • Under Syphon -> Blackmagic
  • Audio/Video Source, select FrameBuffer from dropdown
  • Video Output Mode, set to desired output, in my case NTSC:

OUTPUT from Mac to Visual Cortex on 1st Thunderbolt Blackmagic Intensity Shuttle:
Shuttle YPbBr outputs connected via RCA to LZX Visual Cortex YPbBr inputs

INPUT from Visual Cortex to Mac on 2nd Thunderbolt Blackmagic Intensity Shuttle:
Visual Cortex YPbBr outputs connected via RCA to Shuttle YPbBr inputs

Capture using software of your choice, Blackmagic Media Express, Premiere, Etc. Configure each Thunderbolt Intensity Shuttle within Blackmagic Desktop Video Setup.

NOTES: This has worked for me using 2011 MacPros and later. I have no firsthand experience with USB3 versions of the shuttles. My understanding is they can be troublesome to setup with certain chipsets. In the setup I describe above, things can sometimes finicky to setup, especially if the hardware has been recently configured differently. I find it helpful to reboot devices regularly while trying to bring each step in the chain online one at a time.

For additional information about running a dual setup, see this thread from Eric Souther here:

Leslie Rollins and I got two Blackmagic shuttles to output from CPU into LZX and back to CPU for capture. You can do it all in MAX/MSP or Premiere and Blackmagic Media Express combo. The patch includes an xfade for feedback. (photo credit to Woody Vasulka)

You can play with the max patch here (granted 2 Blackmagic shuttles are needed):
App: https://www.dropbox.com/s/0pzuinwb1j42n1k/BM_BM.app.zip?dl=0
Patch: https://www.dropbox.com/s/a1vqqh4ic9tr3u9/EightEYES.maxpat.zip?dl=0