Login | Register 

Question about receiving timecode from another computer

General discussion about anything TouchDesigner

Question about receiving timecode from another computer

Postby FaustoB » Thu Aug 02, 2018 9:07 pm

Hello TouchDesigners,

I am trying to get my head around on how to receive timecode from another computer that is not using TouchDesigner.
I have never worked with timecode before, and I am new-ish to TD.

For a project coming up in few months, there will be a computer running Protools (or Qlab TBC), that will play a sound file and will send out a timecode.
Based on the initial project briefing, it looks like there's the option that the timecode could be sent out as LTC, MTC or as individual MIDI notes placed in certain key parts of the soundtrack.

What's not clear to me at the moment is how to I receive one of these timecode into TD?

I'd imagine all 3 options have pros and cons, and each one could be the right choice depending on several factors and type of application.

At the moment what I am up to is:
if we use LTC:
I'd imagine I will need an external sound card to receive the LTC.wav, but what happens if I have few millisec of latency? wouldn't it defeat the purpose to receive an accurate LTC timecode? how do I efficiently receive LTC timecode inside TD?
if we use MTC:
I'd imagine I will need to use an external interface with a MIDI in port? would then a MIDI in CHOP be the way of reading this incoming information? I have read the TD documentation about the MIDI in CHOP but I am a bit confused.
if we use MIDI notes:
I'd imagine I will need the same external interface to receive MIDI notes (or any other MIDI messages), then I will have these notes to trigger cues in TD, which is fine.

I would like to explore the LTC option, but what I like about the MIDI notes option is that if last minute they cut few seconds here and there in the sound track, the MIDI notes could be dragged along these changes to stay true to the events within the soundtrack.
In the same scenario, if they cut few seconds here and there and I'm receiving LTC, my cues triggered by timecode hh:mm:ss:ff will be all out past a certain point.

Lots of questions and a fair a bit of confusion at the moment on my end.
Any help or tip to point me in the right direction would be appreciated!

Thanks in advance for your time.
Posts: 63
Joined: Mon Jan 08, 2018 8:33 am
Location: Sydney, NSW

Re: Question about receiving timecode from another computer

Postby guarana » Fri Aug 03, 2018 2:06 pm

you have a ltc in chop in touchdesigner, it will decode you audio signal. The chain is: audiodeviceIN with the right audio input selected, then ltcIN to decode de timecode signal.
Link the other computer to yours with a audio cable (xlr with audio cards or adapters / auxiliary cable). It's just an audio signal; as long as you're not too low and not too loud (clipping) the signal will be fine and the latency if any is negligeable.

You're right about the cue triggers; with midi cues everything will trigger at the specified time, with timecode based trigger you'll have to adjuste to the right timing.

For easy updated you could simple load a xml or text cuelist in touch an have that specifies what are the cues with some pythong or a good dose of noodleing.
// Philippe Provencher
Posts: 97
Joined: Sun Apr 27, 2014 10:13 pm

Return to General TouchDesigner Discussion

Who is online

Users browsing this forum: Bing [Bot], harveymoon, Majestic-12 [Bot] and 13 guests