Video stream and scene requirements for the Motion detector and its sub-detectors

Image requirements for the Motion detector and its sub-detectors

To configure the Motion detector, do the following:

  1. Go to the Detectors tab.

  2. Below the required camera, click Create… → Category: Trackers → Motion detector.

The Motion detector is based on detecting differences between the current frame and the static background, and it generates an event when there is a movement in the camera FOV.

You can set a number of parameters for all sub-detectors of the Motion detector at the same time.

If necessary, you can change the detector parameters. The list of parameters is given in the table:

ParameterValueDescription
Object features
Record mask to archiveYesBy default, mask is recorded to the archive. To disable the parameter, select the No value
No
Record objects trackingYes

By default, object tracks are recorded to the database. To disable the parameter, select the No value.

To obtain metadata, video is decompressed and analyzed, which results in a heavy load on the server and limits the number of cameras that you can use on it.

No
Video streamMain stream

If the camera supports multistreaming, select the stream for which detection is needed. Selecting a low quality video stream reduces the load on the server.

To ensure the correct display of streams on a multi-stream camera, all video streams must have the same frame aspect ratio.

Other
EnableYesBy default, the detector is enabled. To disable, select the No value
No
NameMotion detectorEnter the detector name or leave the default name
Decode key framesYes

By default, the parameter is disabled. This parameter reduces the load on the server, but at the same time the detection quality decreases.

If you want to decode key frames only, select the Yes value. We recommend enabling this parameter for "blind" (without video image display) servers, on which you want to perform detection.

 For the MJPEG codec, decoding isn’t relevant, as each frame is considered a key frame.

The Number of frames processed per second and Decode key frames parameters are interrelated.

If a local client isn’t connected to the server, the following rules work for remote clients:

  • If the key frame rate is less than the value specified in the Number of frames processed per second field, the detector will work by key frames.
  • If the key frame rate is greater than the value specified in the Number of frames processed per second field, the detection will be performed according to the set period.

If a local client is connected to the server, the detector will always work according to the set period. After disconnecting the local client, the above rules will be relevant again.

No
Decoder modeAutoSelect a processing resource for decoding video streams. When you select a GPU, a stand-alone graphics card takes priority (when decoding with Nvidia NVDEC chips). If there is no appropriate GPU, the decoding will use the Intel Quick Sync Video technology. Otherwise, CPU resources will be used for decoding
CPU
GPU
HuaweiNPU
TypeMotion detectorName of the detector type (non-editable field)
Advanced settings
Alarm end delay10Enter the time in seconds during which the generation of an event won't stop after the motion stops. If motion is detected again within the specified time, it will be considered as one event
Camera positionWallTo eliminate false events from the detector when using a fisheye camera (see Configuring fisheye cameras), select the correct device location
Ceiling
Motion maskYes

By default, motion mask is enabled.

  • If motion doesn't exceed the Sensitivity: Contrast and Sensitivity: Size parameters, the mask cells are colored green.
  • If motion generates an event, the cells are colored red.

To disable the parameter, select the No value.

No
Object trackingYes

By default, the parameter is disabled. Select the Yes value to operate the sub-detectors and to display tracks and parameters (width and height as a percentage of the frame width or height and color) of tracking objects in the preview window:

No
Basic settings
Sensitivity: Contrast12

Specify the values of sensitivity to contrast and object size depending on the scene in the frame:

  • Sensitivity: Contrast. The value must be in the range [0, 20]
  • Sensitivity: Size. The value must be in the range [0, 20]

By default, the values of medium sensitivity are used. These values are recommended for most scenes:

  • Sensitivity: Contrast—12.
  • Sensitivity: Size—9.

If objects are far away and small in size, the maximum sensitivity is required. Recommended values:

  • Sensitivity: Contrast—16.
  • Sensitivity: Size—10.

If a camera is located indoors with a distance to objects of about four meters, the minimum sensitivity is required. Recommended values:

  • Sensitivity: Contrast—8.
  • Sensitivity: Size—8.

Sensitivity: Size

9

By default, the entire frame is a detection area. If necessary, in the preview window, set:

For convenience of configuration, you can "freeze" the frame. Click the button. To cancel the action, click this button again.

The detection area is displayed by default. To hide it, click the button. To cancel the action, click this button again.

To save the parameters of the detector, click the Apply  button. To cancel the changes, click the Cancel  button.

Configuration of the Motion detector is complete. If necessary, you can create and configure the necessary sub-detectors on the basis of the Motion detector (see Standard sub-detectors).