Study On The Algorithm Of Resist Cropping Robust Audio Watermark Based On Wavelet Transformation

With the rapid technology development in network and multimedia, multimedia data has become an important source to People to access information. It has become an international study of the topical issues on how to protect the digital multimedia information copyright. Digital watermarking technologies are an important means of copyright protection, and have been widely studied and used. In order to resist the digital works piracy or tampering, the multimedia secret data-Watermark are embedded into the original information to confirm the validity or integrity of the multimedia file. At present in the Digital Audio Watermarking fields, a number of algorithms have been Proposed, but with the development of multimedia technology, the watermark technology is also looking forward to even greater breakthroughs. Watermarking technology in frequency domain is a trend in the future. As a new theory of time-frequency domain, wavelet transform is promising. Because of its local characteristic, the watermarking technology based on wavelet transform is the most active topic in digital watermarking. This paper proposes a robust audio watermark algorithm based on Discrete Wavelet Transform (DWT) to resist cropping attack. The approach initially transforms the audio signal into wavelet domain by DWT, aiming at extracting the low frequency coefficients. A binary image via Arnold preprocessing embedded in audio low frequency coefficients on wavelet domain through the way of quantization steps. This algorithm extract and detect the watermark did not need the original watermark. Simulation experiments show that the performance of the method is ideal under various signal processing manipulations such as low pass filtering, overlay noise, re-sampling, re-quantization, random cropping, dithering, MP3 compression, especially robust to cropping attacks.