Statistical Digital Watermarks of Audio Signals

Abstract

Introduction. Digital watermarks (DWM) refer to embedding additional information directly into audio signal for digital right management and automatic identification of radiotelephone transmissions in aeronautical, maritime and military VHF communication. The main part. The designed embedding algorithm is based on evaluation of sliding frame to embed information or no regarding to distortions introduced by DWM. Watermark location is grounded calculation of distances norm between received and maximum likelihood estimated signal vectors in the domain of Discreet Fourier Transform and doesn’t need for any marking and synchronizing measures. Robustness of DWM against quantization, filtering, additive Gaussian noise, digital format conversion is provided by multichannel narrowband DWM transmission and application of BCH (63,30,6) error-correction code. The proposed algorithm demonstrates watermark inaudibility because of preserving signal power before and after data embedding and searching the most suitable frames for DWM positioning. Conclusion. The proposed algorithms provide advanced compromising solution of audio watermarking process: data payload – inaudibility – robustness. The designed algorithms are applicable both in analog and digital channels for transmission monitoring and digital right management.