We supply a list of cameras which we regularly use for projects and we know that work well. We have done extensive testing with Axis Cameras and have found that the Q3515 with 9-22mm lens works for many scenarios.
We recommend H.264 as a video codec. In general any camera that can supply a valid RTSP stream should work - instructions for set up vary per camera and can be found in your cameras manual. If you can open the camera, using RTSP with the popular VLC tool, you should be able to open the camera with SmartVis Identifier. However, unfortunately all implementations of RTSP streams by camera manufacturers are not created equal and performance can vary with different cameras.
To optimise the quality of stream we recommend a direct connection to the camera, with a high quality setting. In general the higher the bits-per-second (bps), the better the recognition performance. If you can see block compression artefacts in the video stream, then this is a sign you need to increase the bit rate.