3vr P-Series SmartRecorder, Руководство по установке

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3VR Facial Camera Requirement Chart:
1. Face Size
35 pixels between the eyes required.
Rules of thumb:
The field of view when subject is in focus must be less than 4.5 feet,
or the face width must be at least 1/7 of the field of view.
2. Zoom
Zoom lens recommended: 5-50mm
(5- 15% angle of view)
3. Vertical Slope
Recommended: 20% slope from eye level, (see example)
Rule of thumb: the middle of the nose should be higher or at least the
same level as the bottom of the earlobes.
4. Horizontal Angle
Rule of thumb:
The image must simultaneously show both ears of the subject.
5. Lighting
High quality required with wide dynamic range.
Well lit, no harsh shadows or glare.
6. Event Length
There must be a period of time during which the subject is in focus,
large enough (face 1/7 of the field of view), well-lit, facing the camera
so that both ears are visible, and the middle of the nose is above the
bottom of the earlobes.
Recommended: 3 seconds, (minimum 2 seconds)
7. Camera Features
B&W or color (appropriate to lighting conditions)
Backlight control sometime helpful
Manual or Auto-Iris Lens (as appropriate to application)
Examples
Doorways, Hallways, Entrances, Exits
Queue Lines
Teller Lines