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Optimising SecuritySpy’s AI Object Detection

The new AI-powered motion detection features in SecuritySpy version 5 use deep neural networks to detect the presence of humans and vehicles. This allows for highly-accurate triggering of recordings and notifications of just the events that you are interested in.

The AI algorithms output a prediction probability, indicating the likelihood for the presence of a human or vehicle, and you can choose the threshold at which this triggers recording and notifications. Generally, a threshold of 50% gives good results.

However, the accuracy of the AI depends on many factors such as the distance to the subject, lighting, resolution and quality of the camera. You might find that the threshold you have chosen is letting through too many false-positive triggers, or conversely is preventing real motion from generating a trigger.

To see how the AI is performing on your system, create a folder called “AI Predictions” in the SecuritySpy folder within your Home folder (to get to the Home folder, click the Go menu in the Finder and select Home). Then, whenever a video frame is passed through the AI, SecuritySpy will annotate the frame with the motion area and prediction probabilities, and will save it to this folder as an image file. Inspecting these images allows you to determine what the AI is “seeing”, and will therefore allow you to adjust your trigger thresholds for optimum results on your system.

Here are some examples of these annotated images (cropped to just the relevant area):

annotated1 Continue reading