Metrics
Heart Rate
Beats per minute recovered from the pulse waveform. Core metric.
Core metric. The most reliable output of the measurement.
Definition
Heart rate is the number of cardiac cycles per minute, reported in beats per minute (bpm). neccessory recovers the pulse waveform from the face and reads its rhythm to produce the heart rate, with a per-metric confidence value.
- Unit:
bpm(integer) - Averaging window: live estimate stabilizes within ~10 seconds; the final value is the best window across the full measurement.
- Result field:
cardiac.heartRate.value, withcardiac.heartRate.confidence.
Range
| Value | |
|---|---|
| Typical resting adult | 60–100 bpm |
| Reported range | ~40–180 bpm |
Trained athletes can sit below 60 bpm; heart rate rises with activity, stress, and stimulants.
Works when
- The subject is stationary and the camera is stable.
- The face is well lit and unobstructed.
- The camera runs at a steady frame rate (~30 fps).
Does not work when
- The subject moves significantly, talks, or changes expression.
- Lighting is dim, uneven, or flickering.
- The face is far from the camera, partly out of frame, or heavily obscured.
Confidence
Heart rate carries a per-metric confidence (0..1) in the result, and inherits
the top-level signal quality. Gate your display on both:
below the reliability floor the value is returned as null rather than a
fabricated number.
See the full disclaimer.