Dahua Technology IPC-HDW5842T-ZE, Operation Manual

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Operation Manual
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The target should occupy no more than 10% of the whole image.
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The target size in the image should be no more than 10 × 10 pixels. The size of abandoned object
in the image should be no less than 15 × 15 pixels (CIF image). The target height and width
should no more than a third of the image height and width. The recommended target height is
10% of the image height.
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The brightness difference of the target and the background should be no less than 10 gray levels.
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The target should be continuously present in the image for no less than two seconds, and the
moving distance of the target should be larger than its width and no less than 15 pixels (CIF
image) at the same time.
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Reduce the complexity of surveillance scene as much as you can. Intelligent analysis functions
are not recommended to be used in scene with dense targets and frequent illumination change.
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Avoid areas such as glass, reflective ground, water surface, and areas interfered by branch,
shadow and mosquito. Avoid backlight scene and direct light.
8.4.1 Global Configuration
Set global rules for IVS, including anti-disturb, depth of field calibration, and valid motion parameter
for targets.
Calibration Purpose
Determine corresponding relationship between 2D image captured by the camera and 3D actual
object according to one horizontal ruler and three vertical rulers calibrated by the user and the
corresponding actual distance.
Applicable Scene
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Medium or distant view with installation height of more than three meters. Scenes with parallel
view or ceiling-mounted are not supported.
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Calibrate horizontal plane, not vertical walls or sloping surfaces.
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This function is not applicable to scenes with distorted view, such as the distorted views captured
by super wide-angle or fisheye camera.
Notes
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Calibration Drawing
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Calibration area: The calibration area drawn should be on one horizontal plane.
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Vertical ruler: The bottom of three vertical rulers should be on the same horizontal plane.
Select three reference objects with fixed height in triangular distribution as vertical rulers,
such as vehicle parked at roadside or road lamp poles. Arrange three persons to draw at each
of the three positions in the monitoring scene.
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Horizontal ruler: Select reference object with known length on the ground, such as sign on
the road, or use a tape to measure the actual length.
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Calibration VerificationAfter setting the ruler, draw a straight line on the image, check the
estimated value of the straight line, and then compare this value with the value measured in the
actual scene to verify calibration accuracy. In case of major difference between the estimated
value and the actual one, fine-tune or reset parameters until the error requirement is met.