The metadata analytics stream is delivered via the RTSP stream with a special parameter. You need to append “analytics=polygon” in your RTSP request.
- Neither video nor audio, just metadata enabled analytics stream
- The available video&audio in camera=1 channel and metadata analytics stream
- Video, audio and all metadata streams
Time synchronization is vital in this implementation, so the same NTP server should be used in the camera, clients, and the VMS server.
While implementing forensic search, you should pay attention to “Source” and “Object ID” in the XML document. Object ID may disappear and appear again depending on the scene. In 10.6, MOTE data did not have a "Source" field. In 10.9 and later, VideoMotionTracker is added as a source. AXIS Object Analytics data has “=objectanalytics”. NB! Not every frame contains object classification when AXIS Object Analytics is activated, it depends on the scene. While merging the query results, object classification is not reliable, the Object ID is more reliable. However, Object ID may change as well but you can follow it via Object tree specification.
Another important point to keep in mind is that the analytics metadata stream provides "raw" data that you need to filter while querying. It constantly delivers XML files even if there is nothing going on in the scene. It is not good enough to use directly like normal event data in the event stream, where event stream only sent packages once something occurs.