Dahua HDCVI series, User Manual

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Figure 4-111
This function allows you to be informed when video is blurry, over exposure or color
cast occurs. You can enable alarm output channel and then enable show message
function. Click the Rule Set button, or move the cursor to Set button and then click the
Enter button on the front panel, the interface is shown as below. See Figure 4-112.
You can check corresponding type and then input alarm threshold.

Stripe: The strip occurs when the device is old or there is electronic interference.
There may be cross strip, vertical strip, slanting strip and etc.

Noise: The video noise refers to the blurry video, poor video quality. It may result from
the optical system distortion or the hardware problem during the video transmission
when recording.

Color cast: Usually the video is color containing RGB. When these three colors
displayed in abnormal rate, we can say color cast occurred.

Out of focus: The clear video presents abundant video details. The video definition
decreases when the distortion event occurs. The out of focus event may result from
many sources such as video transmission, processing and etc.

Over exposure: The color brightness refers to the image pixel intensity. Black is the
darkest and the white is the brightest. We use number 0 to stand for black and use
number 255 to stand for white. Once the brightness threshold of the whole image has
exceeded the threshold value, it means the image is over exposure.

Threshold: The value ranges from 1 to 30. System can generate an alarm once the
value is higher than the threshold you set here.