A wireless function of an audio source device is enabled to pair the audio source device with a wireless headset. Subsequently, recording is initiated by tapping a “record” button on the headset, and the system guides a user to select an audio format and confirm recording settings. During the recording process, a built-in microphone of the headset acquires an audio signal in real time, and the acquired audio signal is subjected to denoising and signal amplification. The processed audio signal is then converted into a digital signal. A watermark is embedded into the processed digital signal, and a watermark assessment value is calculated. Whether the watermark has been embedded is verified by performing comparison on the basis of the watermark assessment value. The digital signal is then converted into an analog signal to reconstruct an audio signal. Finally, the system performs watermark detection on the reconstructed audio signal.