Automatic digital audio tampering point positioning method based on BIC (Bayesian information criterion)

Abstract

The invention belongs to the technical field of digital audio signal processing and discloses an automatic digital audio tampering point positioning method based on the BIC (Bayesian information criterion). The method comprises the steps as follows: performing active voice detection on a to-be-detected tampering signal to determine a silence fragment in the voice signal; sequentially extracting the Mel-scale frequency cepstral coefficient characteristic of each frame after framing of the silence fragment, and performing long window framing in time sequence; calculating the BIC value of each long-term characteristic frame; taking all crest points in a sequence constituted by BIC values of all long-term characteristic frames as suspicious tamper points, and cutting off the silence fragment front and back with the suspicious tamper points as midpoints; calculating a BIC value sequence of each cut-off window containing suspicious points. Automatic positioning of digital audio tampering points is realized; compared with a traditional tampering detection method, the method has the advantages that the calculated amount is reduced, the omission ratio of the tampering points is reduced, thethreshold selection problem is solved; the method has robustness for the condition of covering of noise with the tampering points.

Description

technical field [0001] The invention belongs to the technical field of digital audio signal processing, in particular to a method for automatically locating digital audio tampering points based on Bayesian information criterion. Background technique [0002] At present, the existing technologies commonly used in the industry are as follows: [0003] With the development of computer and Internet-related technologies, the way people exchange information is rapidly shifting from analog to digital. The advantages of easy storage, editing and dissemination of digital audio data bring a lot of convenience and fun to people's daily life. Most people can use audio editing software to splice, add noise and transform digital audio files simply and quickly without any professional knowledge. and so on. However, while the digital age brings convenience to people, it also brings hidden dangers, that is, the issue of digital information security. Digital audio tampering detection is a...

AI Technical Summary

Problems solved by technology

[0006] (1) There is no unified digital audio tampering and positioning standard operating procedure, and there is no unified evaluation standard for the experimental results;

[0007] (2) At present, most traditional digital audio tampering detection methods have a large amount of calculation and inaccurate positioning;

[0008] (3) The current digital audio tampering point detection scheme cannot be automated, and requires researchers to use empirical knowledge to set the threshold as a criterion, and the adaptability to different database signals is poor

[0010] The establishment of a standard operating procedure for the location of digital audio tampering points is groundbreaking and oriented for subsequent research work. It is convenient to establish a special experimental voice database, establish a unified evaluation standard for future experimental results, and basically establish a tampering point detection research system; tampering The biggest difficulty of point positioning is precise positioning, and the present invention provides a technical means for precise positioning; there is no unified database, and most of the heuristic research programs are poor in adaptability, so automatic detection is useful for both research work and application. great significance

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