Video Trigger
Free Motion Detector App for Media Artists
Attach a camera and trigger sounds whenever occupancy is detected in six user-defined areas of the video image. You have complete control over the playback logic and signal routing. Surround is supported. (If you want to trigger a video instead of sounds, see my other app, Video Triggers Video.)
I designed Video Trigger for artists who want to experiment with interactivity without building custom hardware or software. It aims to answer the question that I hear from many of my students:
“How do I make a sound play when somebody walks by?”
The answer often involves micro-controllers (like Arduino), or software (like Processing, pd, vvvv, Lily, Isadora, or MAX/MSP/Jitter). In the long-run these options provide much greater rewards, but if you have modest needs, Video Trigger is a painless way to get started.
It works with any Quicktime video input device, like the Apple iSight, DV camcorders, and industrial cameras. Video Trigger can play up to six sound files (AIFF or WAV, 1-16 channels) through any Core Audio sound hardware (1-16 channels) with complete control over signal routing.
NOTE: Video Trigger is not security software. It won’t email you when somebody breaks into your house. Try iSpy, BTV Pro, SecuritySpy, Blue Iris, Periscope (discontinued), KeyCamX (discontinued?). Also, MacTheClapper triggers an applescript whenever it hears a double-clap through your computer’s microphone!
VPT (Video Projection Tool) is a free app by HC Gilje that handles all kinds of complicated video projection tasks (cueing, mixing, effects, keystoning, etc…). He made a VPT extension based on Video Trigger so you can use a camera to trigger any VPT function.
Download Current Version
2009-01-10 (Mac Intel/PPC)
Jan 10, 2009, 17MB with source “patches” for MAX/MSP/Jitter 5. (Tested with Mac OS 10.5 Leopard.)
Please read the Video Trigger Guide for instructions and a detailed Changelog.
For Snow Leopard compatibility you must install Quicktime 7.
There is no Windows version. If you are a MAX/MSP user and want to compile your own, my download link points to a Mac disk image which you can open with HFSExplorer on Windows. Inside you will find the cross-platform source patches.
Known Bugs in this version:
- When you load a new sound file, the “Choose Outputs” screen will show no connections, but sometimes the old connections are still active. Choose new connections to override the old ones.
- Sometimes if you choose the “Resume Playing” option while a sound is playing, it might not resume properly on the next trigger. Choose “Start Playing” and trigger it once. Then you can choose “Resume Playing” when it’s done.
- “Video Hardware Settings” might show irrelevant information, but it will still work.