Rendering sound-controlled video

  • I'm using Isadora to process videos a lot for non-realtime stuff as I find it extremely intuitive working in realtime even if dropping frames and then rendering the whole thing properly.

    What I can´t figure out yet though is a way of rendering vids that are affected by sound. Any suggestion? 
    Right now I am playing a video with sound and running Isadora sound output through Soundflower to have that audio analyzed by the Sound Level Watcher actor. But when I render with rendering speed set to 50% or something the sound obviously slows down so I guess that wouldn't work... 
  • Tech Staff

    This is something I had asked for before (need to located thread.. might have been feature request?)
    I would like to be able to select an audio file in the output settings, that will be analyzed at the same speed as the video is being rendered.
    This was a feature of Visual Jockey, I use to render to audio loops that I had at different BPMs. Was great for creating clips for mixing.

  • Isadora does not have the ability to capture sound output when rendering to the stage. When rendering in real-time, I use Audio Hijack Pro on the Mac to capture the sound output, and the splice that into the final movie. For non-real time rendering, there really isn't a solution unfortunately.

    Best Wishes,

  • I wonder if anyone ever tried storing the values of the sound input analysis (amplitude or freq. intensity.. whatever really) into a Data Array and then recalling them while rendering offline. I'm giving it a try right now.

  • Tech Staff

    Great Idea.. do let us know how this goes.. might be a very useful set of actors come out of this.

  • Going a different route and it seems to be working, not sure how reliable this is but first tests look ok to me.

    I am using Ableton  in combination with Isadora.  I made the simplest max4live device to convert volume to a slider automation so I can record it in the arrangement view, kinda like AE "convert audio to keyframes". 
    Once that automation is recorded I copy it to a midi track and send it out as a midi control message to Isadora (max4live again). At this point I can forget about the audio really. 
    Next step is slow down the bpm of Live according to Render speed (50% for instance). Then start rendering and press play on Live. The automation is played at half speed while the movie is rendered. 
    This is just a first test really, but my guess is it might work, it might be not entirely accurate but for now, when I put the rendered video in Live the audio seems to sync perfectly. 
    Looking forward to know what you guys think of this solution. 

  • Audio Hijack Pro worked great Mark THANKS!!!!

    xoxo, AK