Robust digital audio watermarking algorithm in view of time-frequency analysis

Abstract

The invention provides a robust digital audio watermarking algorithm in view of time-frequency analysis. The algorithm comprises steps of: first subjecting a selected audio segment to non-overlapping short-time Fourier transform to obtain a time-frequency distribution map of an audio signal, performing windowing and blocking in the low and medium frequency range of the time-frequency distribution map, and randomly selecting a characteristic energy block with low energy as a specific position for embedding a watermark; embedding generated binary watermark bits into the corresponding characteristic energy blocks by means of an extended code by using an improved spread spectrum watermark embedding method; after the watermark embedding, obtaining the characteristic energy blocks with embedded watermark by means of a watermark embedding position conveyed by a watermark embedder, and recovering a watermark sequence by using a watermarked characteristic energy block vector and the plus or minus characteristic of spread code inner product. The algorithm can guarantee the quality of a main signal by embedding the watermark into the low-frequency and low-energy position of the frequency domain, and can still recover the watermark after the watermarked signal is subjected to quantification, noise, amplitude zooming, AAC coding compression and low-pass filtering.

Description

[0001] technology neighborhood [0002] The invention relates to the technical field of digital watermarking, and is mainly a design invention for finding characteristic energy blocks in the time-frequency domain for embedding and extracting watermarks, and in particular to a robust audio watermarking algorithm from the perspective of time-frequency analysis. [0003] technical background [0004] With the rapid development of modern communication and multimedia technology, digital multimedia products are becoming more and more popular, and people can easily and quickly obtain various digital images, audio, video, animation, software and text, etc. It inevitably brings many security problems, illegal copying, copyright violation, malicious tampering of digital information, etc. Because of this, a digital watermarking technology that can effectively protect digital multimedia products has attracted extensive attention from researchers and has also developed rapidly. Digital aud...

AI Technical Summary

Problems solved by technology

For audio watermarking technology, the original domain and time domain, and the time domain watermarking algorithm directly embed the watermark in the digital audio signal in the time domain. Compared with the transform domain watermarking algorithm, this method is easy to implement and requires less computing resources. There are relatively complete time-domain watermarking algorithms in the existing literature, but such algorithms generally have the disadvantage of not being robust enough for file compression and filtering.

The transform domain is mainly divided into the frequency domain and the time-frequency domain. A large number of existing audio watermarking algorithms are implemented in the frequency domain. The existing algorithms show that when embedding the watermark in the frequency domain, the time domain characteristics of the signal are not considered, which is difficult. The relationship between the imperceptibility of the main signal and the robustness of the watermark

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