Video analytics often mean acting on some pre-defined event producing analytics. What if you can get hold of the underlaying analytics to process and create your own specific events, logs or visualization?
Scene Me replaces my previous ACAP MQTT Me and Radar Me (they are no longer maintained). Scene Me is an extension of MQTT Me with the additional support of publishing analytics data. The analytics in this case are trackers, objects and scenes. Trackers is the data of moving objects within the camera view. Tracker data is published continuously while the video object moves across the scene. Trackers can be used for real-time event filters detecting specific behavior or visualization/augmentation. When the tracker loses the video object an “object” is published. An object is a data structure that includes place of birth/death and time of birth/death. While a tracker targets real-time processing, objects target post-processing applications that have no need to process trackers. The third type, “scene” is a data structured that is published when a tracker fulfils a specific behavior filter during the time a tracker is active. A scene is a filter of place-of-birth, minimum size, minimum age and minimum vertical and/or horizontal movement. Scenes are “events”, similar to “motion detection” but having multiple properties, making it possible to detect specific behavior. Scenes are also automatically published on the ONVIF event stream.
What about Integration?
MQTT is a publish/subscribe protocol where data is published with a topic and a payload. MQTT clients do not connect directly to the device, they connects to a MQTT broker. Multiple clients can subscribe to teh same topic can also publish messages. The broker becomes the system data bus. A client may say to the broker “send me all the messages with the topic “tracker/#”. This will give the client all the trackers from all the cameras in a single subscription. It does not need to connect to each end every camera. It is a single-point-of-integration and at the same time de-coupling the publisher from the consumer. The subscriber does not need to not have direct access to the device producing the data.
This integration requires a MQTT broker. Installing and operating a broker is easy. If you do not have any possibilities hosting a private mosquitto broker, you can use a public enterprise MQTT broker service on Internet (CloudMQTT, HIVEMQ or other).
Does this integrate with my VMS?
To my knowledge there are no VMS that have a built-in MQTT client. I believe it is just a matter of time. However, there are work-arounds to integrate MQTT messaging into a VMS depending on use-case.
Scene Me supports “scenes”. A defined scene in Scene Me will be automatically sent as an “event” on the ONVIF event stream that most VMS support. For this case you do not need an MQTT broker to make the integration.
Scene Me can subscribe to a user defined MQTT topic and generate an ONVIF event that a VMS can monitor. This makes it possible for a 3:rd party MQTT client ( e.g. an Android/IOS MQTT Dashboard) to trigger actions in the VMS, using a camera with Scene Me as a bridge/proxy.
Node-Red, an integrators dream
A VMS is a Video Management System. Counting objects, visual augementation, controlling lights, sending alerts, optimizing building/business automation systems may not require a VMS. What is needed is a Data Management Service that can integrate and process data from and to a VMS, other devices or other systemes. As long as devices and systems have some public API you can integrate.
As an example, the following screenshot shows how Node-Red sends a Scene Me Video analytics object to a database, email, twitter, file and http at the same time.
The user documentation [PDF] describes the overview of Scene Me.
As always, this is a freeware ACAP service but license registration. License registrations requires an “Axis MyAccount”. Go to Axis Portal for ACAP license registation, register the serial number of your camera and select “Free application” and search for “Scene Me”. Download and install the license key file in you Axis Device.
Supported Axis Devices
All Axis devices based on MIPS or ARM7hf with firmware 6.50 or later. In order to utilize video analystics, the firmware must be 9.20 or later.
Note: If you have previously installed MQTT Me, remove that ACAP before starting Scene Me. You may also need to adjust your integration as some topics have changed.
Release notes [TXT]