Audio device and method for adding watermark data to audio signals

摘要

An audio device comprises a processor, an audio processing module, a high frequency noise generating circuit, a first switch control circuit, a second switch control circuit, a low pass filter circuit and an adder circuit. The audio device generates a watermark data, an original audio signal and a high frequency noise signal. The high frequency noise signal pass through a first switch control circuit and a second switch control circuit according to watermark data. A low pass filter circuit filters the high frequency noise signal received from the first switch control circuit to form a first add data. An adder circuit receives the first add data from the low pass filter circuit, receives the high frequency noise signal from the second switch control circuit as a second add data, and adds the first add data and the second add data to the original audio signal.

主权项

1. An audio device, comprising:
a processor that generates a watermark data, the watermark data comprising high level logic signals and low level logic signals; an audio processing module connected to the processor, wherein the audio processing module generates an original audio signal; a high frequency noise generating circuit that generates a high frequency noise signal; a first switch control circuit connected to the processor and the high frequency noise generating circuit; a second switch control circuit connected to the processor and the high frequency noise generating circuit, wherein the high frequency noise signal passes through one of the first switch control circuit and the second switch control circuit when the watermark data is the high level logic signals, and the high frequency noise signal passes through the other one of the first switch control circuit and the second switch control circuit when the watermark data is the low level logic signals; a low pass filter circuit connected to the first switch control circuit, wherein the low pass filter circuit filters the high frequency noise signal received from the first switch control circuit to form a first add data; and an adder circuit that receives the first add data from the low pass filter circuit, receives the high frequency noise signal from the second switch control circuit as a second add data, and adds the first add data and the second add data to the original audio signal.