3vr P-Series SmartRecorder, Руководство по установке

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3VR SmartRecorder Installation and Configuration Guide
2. Horizontal Angle Facial analysis requires a clear image of the full face, directly facing the camera -
with minimal turning of the head to the left or right (horizontal angle) relative to the camera.
Rule of thumb: the image must simultaneously show both ears of the subject.
3. Vertical Angle
Facial analysis requires a clear image of the full face, directly facing the camera - with mini -
mal tilting of the head up or down (vertical angle) relative to the camera.
Rule of thumb: the middle of the nose should be higher than or at least the same level as the bottom of
the earlobes. If the middle of the nose appears below the earlobes, the vertical angle is too high.
Cameras need to be mounted low enough or far away enough so that the vertical angle or slope does
not exceed 20% above the eye level when subjects are in focus in the foreground. Given an aver -
age eye height of 5 feet, a camera 10 feet away can not be mounted higher than 20% of 10 feet (2
feet) above the eye height of 5 feet - so not higher than 5 + 2 = 7 feet. A camera 20 feet away can be
mounted as high as 9 feet (20% of 20 = 4 feet above 5 feet, 4 + 5 = 9).
See “Determining Camera Mount -
ing Height” later in this section for more details.
Excellent Placement
No horizontal angle
Both ears fully visible
Poor Placement
Horizontal angle too large
Can’t see both ears
Maximum Acceptable
Horizontal angle marginal
Some of each ear visible
Excellent Placement
No vertical angle
Middle of nose above earlobes
Poor Placement
Vertical angle too large
Middle of nose below earlobes
Maximum Acceptable
Vertical angle marginal
Middle of nose at earlobes