SAFR supports any IP camera that allows RTSP h.264 or h.265 streaming.  

In general, for Facial recognition, you want to have at least a 2MP camera and sufficient optical zoom so that faces at the target distance are 50 pixels wide.   Also, its good to have a camera that produces a well exposed, sharp image under the lighting conditions for the site.

The following tool can be used to enter your camera resolution and horizontal angle of view and identify the distance at which safr will recognized.

https://docs.real.com/support/tools/recognition_quality_calculator

As an example, following is with 2MP camera at 50° angle of view:

You can see that recognition will be high quality up to 15 feet and after that it drops off.
You can also see that at 15 feet, the camera will cover a 15 foot wide walkway.

By comparison, if you can zoom your camera to 20° horizontal angle of view, you can recognize up to 50 feet as shown below.  

The higher the resolution (4MP, 5MP, 4k) and lower the angle of view, the better recognition will be at a distance.