Ordinary video provides imagery that is easily interpreted by humans, for validation and recognition of the state of the animals. Surveillance cameras are used in abundance in the western world, and still human operators are almost exclusively used to detect anomalies. This will not be a sustainable solution for wildlife security, where computers have to do this job and automatically detect anomalies. For instance, the human intruder is at first glance not easy to spot for the human eye in the image below.
Thermal cameras measure temperature differences very accurately, and can detect warm objects from a colder background. Thermal cameras are thus suitable for animal detection and can for instance be used to locate and track the Big Five out on the savannah, in particular the endangered rhino, during both day and night. The picture below shows a snapshot from one of the videos showing the 'hot spot' contour of a rhino. These hot spots are easy for the computer to generate, and the basis for automatic detection, classification and tracking of the animals.
The colors indicate different classes, and the ellipses are used as extended object models to catch the size and orientation of the animals and possible humans.
Pairing together the same objects in these two images as indicated by the two arrows is simplified after successful registration of the two video streams. Registration means that the two video streams are synchronised both in time and space, so the thermal camera essentially adds one more color to the video. The image below shows an example of thermal video overlaid a standard video after registration, where objects within a certain temperature interval are marked with green. The thermal camera has a more narrow filed of view, which is indicated with the red rectangle.
The hot spot can further be used to cut out images which are then sent to the rangers and researchers. All aerial footage above is performed by UAS and operator provided by Superfly.se.
At Kolmården we also have access to an aerial platform that does not need an operator, limited battery power, safety risks or load restrictions. We use the cabin car over the wildlife park as a bearer for our sensor systems. This cable car system is operated all day long, when the park is open for visitors. The camera system consisting of a video camera and a thermal camera mounted on a gimbal. A planning algorithm decides the roll and pitch angle of the gimbal based on a geographical model of the enclosure to be monitored and a terrain elevation map.The goal with this is to scan the whole enclosure in an efficient way.