sertxudev / audio-demo

JSLTC

Demo to read live ltc audio with js

NOTE: just a POC to test that it works

I am using VB-Cable to help route the audio. https://vb-audio.com/Cable/
I am using piXtimecode to verify LTC. https://apps.microsoft.com/detail/9MT05F4N77XZ
Generate LTC from https://elteesee.pehrhovey.net/

Using https://github.com/bitfocus/libltc-wrapper to parse LTC.
Using https://github.com/almoghamdani/audify to handle audio.

graph LR;
  id0-0[mpv] --> id1;
  id0[gen.js] --> id1[OR];
  id1[OR]-->id2[VBCABLE Input];
  id3[VBCABLE Output]-->id4[LTC Viewer];
  id2 -.- id3;
  id3 --> id5[read.js];

Loading

have mpv play audio to specific device

mpv.com --audio-device='wasapi/{519e9287-141e-48ff-8422-338c3dbdbb7d}' .\LTC_01000000_10mins_25fps_48000x16.wav

list devices for mpv

mpv.com --audio-device=help

List of detected audio devices:
  'auto' (Autoselect device)
  'wasapi/{519e9287-141e-48ff-8422-338c3dbdbb7d}' (CABLE Input (VB-Audio Virtual Cable)) Audio))
  'openal' (Default (openal))
  'sdl' (Default (sdl))

NOTE: you need to set the correct deviceId for your system in both gen.js and read.js.

To get deviceId run list_dev.js
gen.js generates LTC audio based on wallclock time.
read.js reads audio from device and prints out LTC timecode.

Big help from https://github.com/philhartung/aes67-sender and https://github.com/philhartung/aes67-monitor on how to get audio working.

works with node v14.15.4 and windows.

Using WINDOWS_WASAPI as backend. Default is WINDOWS_ASIO but every run cuts out the audio. It only sees some interfaces and not all.