Distance-Based Emergency Video Recording Trigger

The patent applies local quality by making each camera's recording decision independent and location-specific. Each terminal device autonomously determines whether to start video recording based on its own distance to the emergency signal source, rather than all devices following a uniform rule. This resolves the contradiction by ensuring only cameras in relevant locations (within threshold distance) consume storage resources, while maintaining reliable evidence capture from appropriate positions.

The patent applies parameter changes by using distance as a dynamic parameter to control video recording activation. The system compares the distance between the terminal device and emergency signal source against a predetermined threshold value. This resolves the contradiction by providing an objective, quantifiable criterion for activation, eliminating false positives from subjective judgment while maintaining high emergency response efficiency through automated distance-based decision making.

The patent applies self-service by enabling each terminal device to autonomously determine its own recording status based on local distance calculations. Each device independently compares its distance to the emergency signal source with the threshold value and makes its own decision to start or stop recording, without requiring centralized control or complex inter-device communication. This resolves the contradiction by reducing system-level complexity while effectively preventing unnecessary recordings through distributed autonomous decision making.