A video camera, a computer-implemented method, and a computer-readable storage medium. The video camera including one or more microphones and a processor. The processor is configured to: acquire an output from the or each microphone; apply one or more pre-analysis filters to the or each acquired output, wherein the or each pre-analysis filter determines if the or each acquired output contains a corresponding predetermined feature of interest; and analyse the or each output, when it is determined by the or each pre-analysis filter that the corresponding output contains at least one predetermined feature of interest.