Reference / Effects / Drivers
Updated
Beat trigger
Beat trigger is a Drivers effect.
What it does
Section titled “What it does”Fires an event on each beat marker, on each beat found in the sound, or each time one band of the sound gets louder than Threshold. It has four sockets: Pulse, 1 on the frame of an event and 0 otherwise, Count, the events so far, Envelope, 1 at each event and falling away over Decay, and Time since last, in seconds.
Every value is worked out from the start of the composition, so scrubbing and exporting give the same numbers.
Parameters
Section titled “Parameters”| Parameter | Control | Range | Default | Unit |
|---|---|---|---|---|
| Events | Dropdown | Beat markers · Detected beats · Level crossing | Beat markers | - |
| Source | Dropdown | This comp · Layer · Clip | This comp | - |
| Audio | Layer | Any layer in the composition | None | - |
| Clip | clip | - | - | - |
| Band | Dropdown | All · Low · High | All | - |
| Sensitivity | Slider | 0 to 100 | 50 | Per cent |
| Minimum gap | Slider | 0 to 1; higher | 0 | Seconds |
| Threshold | Slider | 0 to 1; higher | 0.2 | - |
| Hold off | Slider | 0 to 30; higher | 4 | Frames |
| Decay | Slider | 0.01 to 2; down to 0 and higher | 0.25 | Seconds |
In the Effect Controls panel:
- Source is editable while Events is anything but Beat markers.
- Audio is editable while Source is anything but This comp.
- Clip is editable while Source is set to Clip.
- Band is editable while Events is anything but Beat markers.
- Sensitivity is editable while Events is set to Detected beats.
- Minimum gap is editable while Events is set to Detected beats.
- Threshold is editable while Events is set to Level crossing.
- Hold off is editable while Events is set to Level crossing.
What each control does
Section titled “What each control does”- Events: Beat markers fires on the composition’s beat markers. Detected beats finds beats in the sound, as Composition ▸ Detect beats does. Level crossing fires when the band’s level rises past Threshold.
- Source: the sound listened to, the composition’s mix, one layer of it or one clip.
- Audio: the layer Layer and Clip listen to.
- Clip: the clip Clip listens to.
- Band: the whole sound, below 200 Hz, or above 4 kHz.
- Sensitivity: how readily a beat is found.
- Minimum gap: of two beats closer than this, the stronger counts.
- Threshold: the level the band has to rise past.
- Hold off: frames after a crossing before the next can fire.
- Decay: how fast Envelope falls. It is down to about a third after this long.