To configure face detection tools, do as follows:

1. Select the Facial Recognition object. 
   

2. If you need to use this detection tool for real-time facial recognition, set the corresponding parameter to Yes (1, see Configuring real-time facial recognition).

3. If you need to enable recording of metadata, set Yes in the Record Objects tracking field (2).
4. If the camera supports multistreaming, select the stream for which detection is needed (3). For the correct operation of the Facial Recognition, it is recommended to use a High-quality video stream.
5. If you need to use this facial recognition tool in real time together with FaceCube Recognition Server (see Configuring FaceCube integration), set Yes in Real-time recognition on external service field (4).

6. If you need to save age and gender information for each recognized face, set Yes in the corresponding field (1). 

   
7. If you use a bi-spherical XingYun lens, the detector will analyze two 180^° spherical images by default (see Configuring fisheye cameras). This may decrease recognition quality. To dewarp the image before detection, set Yes in the Camera transform field (2). This parameter is also relevant for other types of image transformation. 
8. Select a processing resource for decoding video streams (3). 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.
9. Set the time (in milliseconds) between face search operations in a video frame in the Faсe detection period (msec) field (4). Acceptable values range: [1, 10000]. Increasing this value decreases the Server load, but this can result in some faces being undetected. 
10. If you need to apply the masks detection tool, set Yes in the Face mask detection field (5, see Configuring masks detection).
11. In some cases, the detection tool may mistake other object for a face. To filter out non-facial objects, select Yes in the Filter false alarms field while calculating the vector model of a face and its recording into the metadata DB (6). If the filtering is on, false results will appear in the detection feed (see Facial recognition and search), but will be ignored during searches in archive.

12. Analyzed framed are scaled down to a specified resolution (7, 1920 pixels on the longer side). This is how it works:

    1. If the longer side of the source image exceeds the value specified in the Frame size change field, it is divided by two.

    2. If the resulting resolution falls below the specified value, it is used further.

    3. If the resulting resolution still exceeds the specified limit, it is divided by two, etc.

       For example, the source image resolution is 2048*1536, and the specified value is set to 1000. In this case, the source resolution will be halved two times (down to 512*384), as after the first division, the number of pixels on the longer side exceeds the limit (1024 > 1000).

       
       

       If detection is performed on a higher resolution stream and detection errors occur, it is recommended to reduce the compression.

       
       

13. Specify the minimum and maximum sizes of the captured faces as a percentage of the frame size (8). 

14. In the Minimum threshold of face authenticity field, set the minimum level of face recognition accuracy for the creation of a track (9). You can set any value by trial-and-error; no less than 90 is recommended. The higher the value is, the fewer faces are detected, while the recognition accuracy increases.

15. Select the processor for the face detection − CPU or NVIDIA GPU (10) (see General Information on Configuring Detection). 
    

    It may take several minutes to launch the algorithm on NVIDIA GPU after you apply the settings.

    
    

16. If you use FaceCube integration (see Configuring FaceCube integration), activate the Send face image parameter (11).

17. Enter the time in milliseconds after which the face track is considered to be lost in the Track loss time field (12). Acceptable values range: [1, 10000]. This parameter applies when a face moves in a frame and gets hidden behind an obstacle for some time. If this time is less than the set value, the face will be recognized as the same.

18. Select a rectangular area to be searched for faces in the preview window. To select the area, move the anchor points .
    

19. Click the Apply button.

Configuration of general parameters for Facial Recognition is now complete.