Adjusting Detection Accuracy
Adjust detection when there are too many alerts or people are missed. The defaults suit most environments.
- On the Settings tab, click Accuracy / speed.
- Choose a value for the item you want to change. See "When to change" in the table below.
- Click Save on the save bar at the bottom of the screen.
| Setting | What it does | When to change |
|---|---|---|
| Detection delay | How long to wait after a person or face appears before counting it as detected. | Only when certain if false alarms occur |
| Person detection accuracy | The precision of the analysis. Higher precision is slower. | Fast on a Raspberry Pi, Accurate on a PC or Jetson |
| GPU acceleration | Runs analysis on the GPU. | Off on integrated or older graphics |
| Analyses per second | How many times per second the video is analyzed. | Raise it only when the device has headroom |
| Person threshold | The criterion for judging something to be a person. | Strict if mannequins or posters are detected |
| Face threshold | The criterion for matching a registered person. | Strict if people are confused with each other |
| Minimum face size | Faces captured smaller than this are not recognized. | Slightly smaller for ceiling cameras, where faces are captured small |
Note
If cameras are currently configured with different values, the screen shows one of them.
Changing a value on this screen and saving applies the same settings to all cameras.
Options and defaults for each setting
- Detection delay: Fast (1s) (default), Normal (3s), or Only when certain (5s). The same time is waited after the person leaves before recording ends.
- Person detection accuracy: Fast, Balanced, or Accurate. New places start at Fast.
- GPU acceleration: devices without a usable GPU run on the CPU regardless of this setting.
- Analyses per second: 5, 10, 15, 20, 25, or 30. New places start at 10. The value is an upper limit; a device that cannot keep up analyzes less often. If the camera is slower, the camera's rate applies.
- Person threshold: Loose, Normal, or Strict. Does not affect speed.
- Face threshold: shown only while face recognition is on.
- Minimum face size: Slightly smaller (60px), Normal (80px, default), Slightly larger (96px), or Large faces only (112px). Shown only while face recognition is on.