고음질을 위한 디지털 오디오 워터마킹에 관한 연구

조병록,정일용,박창균,이강현,Jo, Byeong-Rok,Jeong, Il-Yong,Park, Chang-Gyun,Lee, Gang-Hyeon 대한전자공학회 2002 電子工學會論文誌-CI (Computer and Information) Vol.39 No.3

본 논문에서는 고음질을 위한 디지털 오디오 워터마킹(watermarking) 알고리즘을 제안한다. 오늘날 디지털 저작물을 확인하는데 디지털 워터마크(digital watermark)가 쓰이고 있으며, 영상뿐만 아니라 디지털 오디오 분야도 연구가 활발하다. 특히, 디지털 오디오 분야에서의 워터마크 삽입은 워터마크의 강인성뿐만 아니라 워터마킹된 오디오 데이터 자체의 음질에 상당한 영향을 주게 된다. 오디오 워터마크는 일반적으로 FFT 변환 후 주파수 영역에 워터마크를 삽입하는데, 이때 워터마크 삽입 영향으로 오디오 데이터 음질에 영향을 미치게 된다. 따라서 오디오의 고음질을 유지하면서 강인한 워터마크를 삽입하는 연구가 큰 문제로 대두되었다. 논문에서는 심리음향 모델(Psychoacoustic model) 및 MDCT/IMDCT(Modified Discrete Cosine Transform/Inverse Modified Discrete Cosine Transform)를 사용한 고음질 오디오 워터마킹 알고리즘을 제안한다. 제안된 논문에서, 오디오 워터마킹 알고리즘을 위하여 44.1㎑, 128Kbps, 스테레오 오디오 파일을 이용하였다. 오디오 데이터가 MDCT를 통해 주파수 변환하는 과정에서 256, 1024, 2048 포인트 간격으로 워터마크를 삽입할 수 있다. 50㎳의 RMS 윈도우를 사용했을 때 원 오디오 데이터와 워터마킹 된 오디오 데이터의 전체 RMS 파워의 차이는 0.8㏈이다. In this paper, the authors proposed the digital audio watermarking algorithm for a high quality audio. Today, the digital watermark is used to confirm to the digital copyright protection, not only the digital image but the digital audio study is an activeness in the digital watermarking area. Especially, the watermark insertion in the digital audio area affects deeply not only a robustness but the audio quality of the watermarked audio data. Generally, the audio watermark is inserted in the frequence domain after FFT, the quality of audio data is affected by the watermark insertion. Thus, a high quality audio to be maintained at the same time, the study related a inserting of the robustness watermark happened to a hot issue. In this paper, the authors proposed the digital audio watermarking algorithm using psychoacoustic model and MDCT/IMDCT (Modified Discrete Cosine Transform/Inverse Modified Discrete Cosine Transform). In the proposed scheme, the authors experimented the stereo audio file with 44.1KHz, and 128kbps for the audio watermarking algorithm proposed. When the audio data is processed by MDCT, the watermark is able to insert into the frequence domain with 256, 1024 and 2048 interval. In case of 50㎳ RMS window, it was confirmed that the difference between the original audio data and the watermarked audio data of RMS power is 0.8㏈.

High Quality Audio Watermarking using Spread Spectrum and Psychoacoustic Model

노진수,이강현,Noh Jin-Soo,Rhee Kang-Hyeon The Institute of Electronics and Information Engin 2006 電子工學會論文誌. Journal of the Institute of Electronics Vol.43 No.5

본 논문에서는 심리음향 모델과 MDCT/IMDCT(Modified DCT/Inverse Modified DCT)를 이용하여 고음질 오디오 워터마킹 알고리즘을 제안하였다. 일반적으로 디지털 오디오 워터마크는 디지털 오디오 신호를 주파수 영역으로 변환 한 다음 주파수 영역에 워터마크를 삽입하지만 삽입된 워터마크에 의해 디지털 오디오 음질이 영향을 받게 된다. 제안된 알고리즘에서는 디지털 오디오 데이터를 PN(Pseudo Noise) 코드를 사용하여 확산시킨 다음 심리음향 모델을 참조하여 MDCT 과정을 통하여 오디오 워터마크를 삽입시킨다. MDCT 과정에서 고음질의 오디오를 얻기 위해 필터뱅크 출력의 첨예도에 따라 256, 1,024 또는 2,048 포인트의 윈도우가 선택되어진다. 본 논문에서 워터마크 계수 ${\alpha}$가 2.5 이하일 때, 워터마크의 검출률이 SDMI(Secure Digital Music Initiative)의 제안 조건을 50% 이상 상회 하며, SNR은 4종류의 공격(압축, 절단, FFT, 에코)에 대해 $50{\sim}68dB$ 값을 가짐을 확인하였다. In this paper, we proposed the high quality audio watermarking algorithm using MDCT/IMDCT (Modified DCT/Inverse Modified DCT) with psychoacoustic model. Generally, a digital audio watermark is embedding the frequency domain after frequency transform of the digital audio data but the digital audio quality is affected by watermarking. In our scheme, the digital audio data is spread with PN((Pseudo Noise) code and then audio watermark is embedded in MDCT processing that refers psychoacoustic model. In MDCT processing, according to the shape of filter bank output, the block switching selects a window sequence that has 256, 1,024 or 2,048 points interval for high quality audio. The author confirm that when watermark weight ${\alpha}$ is 2.5 below, the detection ratio of watermark is a satisfied to SDMI's(Secure Digital Music Initiative) recommendation 50% above and SM is $50{\sim}68dB$ range with mainly 4 kind of attacks(Compression, Cropping, FFT and Echo).

High-capacity and Transparent Digital Audio Watermarking using Rounding Reduced-arc MPSK and a Genetic Algorithm

Rizki Rivai Ginanjar,Dong-Seong Kim,Chang-Bae Moon 대한전자공학회 2019 IEIE Transactions on Smart Processing & Computing Vol.8 No.1

In this paper, a novel, high-capacity and transparent blind audio watermarking system based on rounding reduced-arc M-ary phase shift keying (MPSK) is presented. Signal samples of the audio file are divided into several frames and then transformed into the frequency domain using fast Fourier transform. The watermark is embedded in the phase element of the selected samples based on several criteria. Two modified modulation schemes (256-PSK and binary phase shift keying) are used for the embedding process to compare the effects of the M-ary number used in the system. To improve the system, a genetic algorithm is utilized to obtain the best embedding parameters, which produces the optimal output based on the perceptual quality of the watermarked audio and the robustness of the extracted watermark. Experimental results show that the proposed audio watermarking system produces high-quality watermarked audio while loading a huge amount of data.

A Tutorial for Blind Audio Watermarking Scheme

Md. Iqbal Hasan Sarker,Mohammad Ibrahim Khan 한국산학기술학회 2014 SmartCR Vol.4 No.1

Digital audio watermarking is the process of embedding inaudible information into audio data for copyright protection, fingerprinting, carrying information or detecting content manipulation of a musical artwork. In this research, we propose a blind and robust audio watermarking method based on discrete cosine transform (DCT). This algorithm can embed or hide an entire image or pattern, such as a company’s logo or trademark, as a watermark directly into the original audio. Furthermore, it allows blind retrieval of an embedded watermark without the original audio. Performance of the algorithm has been evaluated extensively and simulation results are presented to demonstrate the imperceptibility, robustness and payload of the proposed algorithm.

A Tutorial for Audio Watermarking in the Cepstrum Domain

Alok Kumar Chowdhury,Md. Ibrahim Khan 한국산학기술학회 2013 SmartCR Vol.3 No.5

Embedding watermarks in an audio signal by considering the relation between the mean values of two consecutive groups of samples can lead to a faster and efficient audio watermarking algorithm. In this paper, we propose to divide the host audio signal into non-overlapping frames and then split the frames into two equal-sized sub-frames followed by cepstrum transformation of the samples of these sub-frames. Here, we individually calculate the mean values of the two sub-frames of each frame and change the values to embed watermarks. Depending on the watermark to embed (either 0 or 1), we interchange the mean value of the two sub-frames by selectively changing sample values. The technique of using consecutive sub-frames for selective embedding helps our algorithm to faster and easier determination of the value of the watermark bit. Therefore, our embedding technique and employment of cepstrum representation of samples together make the audio watermarking algorithm highly imperceptible and robust. Experimental results show that our new audio watermarking scheme is robust against various common signal processing attacks, such as amplitude modification, re-quantization, noise addition, resampling, MP3 conversion, etc.

고품질 스테레오 음악을 위한 오디오 워터마크 정보 삽입/추출 기술

배경율(Kyungyul Bae) 한국지능정보시스템학회 2018 지능정보연구 Vol.24 No.2

Since the introduction of MP3 players, CD recordings have gradually been vanishing, and the music consuming environment of music users is shifting to mobile devices. The introduction of smart devices has increased the utilization of music through music playback, mass storage, and search functions that are integrated into smartphones and tablets. At the time of initial MP3 player supply, the bitrate of the compressed music contents generally was 128 Kbps. However, as increasing of the demand for high quality music, sound quality of 384 Kbps appeared. Recently, music content of FLAC (Free License Audio Codec) format using lossless compression method is becoming popular. The download service of many music sites in Korea has classified by unlimited download with technical protection and limited download without technical protection. Digital Rights Management (DRM) technology is used as a technical protection measure for unlimited download, but it can only be used with authenticated devices that have DRM installed. Even if music purchased by the user, it cannot be used by other devices. On the contrary, in the case of music that is limited in quantity but not technically protected, there is no way to enforce anyone who distributes it, and in the case of high quality music such as FLAC, the loss is greater. In this paper, the author proposes an audio watermarking technology for copyright protection of high quality stereo music. Two kinds of information, Copyright and Copy_free, are generated by using the turbo code. The two watermarks are composed of 9 bytes (72 bits). If turbo code is applied for error correction, the amount of information to be inserted as 222 bits increases. The 222-bit watermark was expanded to 1024 bits to be robust against additional errors and finally used as a watermark to insert into stereo music. Turbo code is a way to recover raw data if the damaged amount is less than 15% even if part of the code is damaged due to attack of watermarked content. It can be extended to 1024 bits or it can find 222 bits from some damaged contents by increasing the probability, the watermark itself has made it more resistant to attack. The proposed algorithm uses quantization in DCT so that watermark can be detected efficiently and SNR can be improved when stereo music is converted into mono. As a result, on average SNR exceeded 40dB, resulting in sound quality improvements of over 10dB over traditional quantization methods. This is a very significant result because it means relatively 10 times improvement in sound quality. In addition, the sample length required for extracting the watermark can be extracted sufficiently if the length is shorter than 1 second, and the watermark can be completely extracted from music samples of less than one second in all of the MP3 compression having a bit rate of 128 Kbps. The conventional quantization method can extract the watermark with a length of only 1/10 compared to the case where the sampling of the 10-second length largely fails to extract the watermark. In this study, since the length of the watermark embedded into music is 72 bits, it provides sufficient capacity to embed necessary information for music. It is enough bits to identify the music distributed all over the world. 272 can identify 4 * 10<SUP>21</SUP>, so it can be used as an identifier and it can be used for copyright protection of high quality music service. The proposed algorithm can be used not only for high quality audio but also for development of watermarking algorithm in multimedia such as UHD (Ultra High Definition) TV and high-resolution image. In addition, with the development of digital devices, users are demanding high quality music in the music industry, and artificial intelligence assistant is coming along with high quality music and streaming service. The results of this study can be used to protect the rights of copyright holders in these industries.

Blind Audio Watermarking Technique Based on Two Dimensional Cellular Automata

Hazem Hiary,Abdel Latif Abu Dalhoum,Alia Madain,Alfonso Ortega,Manuel Alfonseca 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.9

In this paper we propose a new method of digital audio watermarking based on two dimensional cellular automata; the method increases the dimension of the audio and uses cellular automata in generating the key of watermark embedding. The watermarking method is blind, and does not require the original host audio or any of its features to extract the watermark; the watermark can be easily extracted using the right key. The experimental results show that the watermarks are imperceptible; and show a high similarity between the original and the watermarked audio. Cosine similarity and peak signal-to-noise ratio were used to measure the similarity between the original audio and the watermarked audio.

Audio Watermarking Using Independent Component Analysis

Seok, Jong-Won The Korea Institute of Information and Commucation 2012 Journal of information and communication convergen Vol.10 No.2

This paper presents a blind watermark detection scheme for an additive watermark embedding model. The proposed estimation-correlation-based watermark detector first estimates the embedded watermark by exploiting non-Gaussian of the real-world audio signal and the mutual independence between the host-signal and the embedded watermark and then a correlation-based detector is used to determine the presence or the absence of the watermark. For watermark estimation, blind source separation (BSS) based on independent component analysis (ICA) is used. Low watermark-to-signal ratio (WSR) is one of the limitations of blind detection with the additive embedding model. The proposed detector uses two-stage processing to improve the WSR at the blind detector; the first stage removes the audio spectrum from the watermarked audio signal using linear predictive (LP) filtering and the second stage uses the resulting residue from the LP filtering stage to estimate the embedded watermark using BSS based on ICA. Simulation results show that the proposed detector performs significantly better than existing estimation-correlationbased detection schemes.

An Efficient Audio Watermark Extraction in Time Domain

Kang, Hae-Won,Jung, Sung-Hwan Korea Information Processing Society 2006 Journal of information processing systems Vol.2 No.1

In this paper, we propose an audio extraction method to decrease the influence of the original signal by modifying the watermarking detection system proposed by P. Bassia et al. In the extraction of the watermark, we employ a simple mean filter to remove the influence of the original signal as a preprocessing of extraction and the repetitive insertion of the watermark. As the result of the experiment, for which we used about 20 kinds of actual audio data, we obtain a watermark detection rate of about 95% and a good performance even after the various signal processing attacks.

Audio Watermarking through Modification of Tonal Maskers

Hee Suk Lee,이우선 한국전자통신연구원 2005 ETRI Journal Vol.27 No.5

Watermarking has become a technology of choice for a broad range of multimedia copyright protection applications. This paper proposes an audio watermarking scheme that uses the modified tonal masker as an embedding carrier for imperceptible and robust audio watermarking. The method of embedding is to select one of the tonal maskers using a secret key, and to then modify the frequency signals that consist of the tonal masker without changing the sound pressure level. The modified tonal masker can be found using the same secret key without the original sound, and the embedded information can be extracted. The results show that the frequency signals are stable enough to keep embedded watermarks against various common signal processing types, while at the same time the proposed scheme has a robust performance.