著者

Xuping Huang Nobutaka Ono Akira Nishimura Isao Echizen

出版者

Information Processing Society of Japan

雑誌

Journal of Information Processing (ISSN:18826652)

巻号頁・発行日

vol.25, pp.469-476, 2017 (Released:2017-07-15)

参考文献数

28

被引用文献数

4

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Reversible audio information hiding and sample-scanning methods are proposed for digital audio content to achieve detailed detection and localization of tampered positions in each frame. The method proposed in this study allows detecting multiple tampering and reusing reliable content as well as avoiding false detection which were impossible for other methods to simultaneously achieve. In the proposed method, the original signal is partitioned into fixed-length frames and then transformed into discrete cosine transform (DCT) coefficients by the integer modified DCT (intDCT). Expansion of the DCT coefficients is applied to embed a content-based hash as a payload. The integer DCT algorithm ensures the reversibility of the transform so that the original data and embedded payload can be perfectly restored to enable blind verification of the data integrity. The perceptual evaluation of speech quality (PESQ) with the listening quality objective mean opinion (MOSLQO), the segmental signal to noise ratio (segSNR), and subjective evaluation results show that the proposed algorithm provides good sound quality (MOSLQO and segSNR are respectively 4.41 and 23.31dB on average for a capacity of 8, 000bps). Detection and localization are accurate in terms of correctly localizing tampered frames in case of insertion or deletion.

著者

Akira Nishimura Nobuo Koizumi

出版者

ACOUSTICAL SOCIETY OF JAPAN

雑誌

Acoustical Science and Technology (ISSN:13463969)

巻号頁・発行日

vol.31, no.2, pp.172-180, 2010-03-01 (Released:2010-03-01)

参考文献数

15

被引用文献数

1 1

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A method of sampling jitter measurement based on time-domain analytic signals is proposed. Computer simulations and actual measurements were performed to compare the proposed method with the conventional method, in which jitter is evaluated from the amplitudes of sideband spectra for observed signals in the frequency domain. The results show that the proposed method is effective in that it 1) provides high temporal resolution as a result of the direct derivation of the jitter waveform, 2) achieves higher accuracy in the measurement of jitter amplitude, and 3) can separate phase modulation that originate in sampling jitter from amplitude modulation that originate in digital-to-analog and analog-to-digital conversion processes. Suitable measurement conditions and measurements to separate the effects of jitter in a digital-to-analog converter and an analog-to-digital converter are described.

著者

Xuping Huang Akira Nishimura Isao Echizen

雑誌

研究報告コンピュータセキュリティ(CSEC)

巻号頁・発行日

vol.2011, no.8, pp.1-8, 2011-11-28

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We propose and implement a content-based tampering detective steganography scheme using acoustic data with probative value in this paper. The purpose is to verify and identify malicious modification. Content-based hash function SHA-1 is adapted to detect tampering. After transforming data from time-domain to frequency domain using integer Discrete Cosine Transform (int-DCT), the amplitude of the highest frequency domain is expanded to reserve embedding capacity which is necessary for hiding hash value and index table for hiding. Lossless embedding and extraction algorithm ensure this scheme a reversible alternative scheme to meet the requirements of acoustic media with probative value. Hash digest is applied to data units after the original data is divided to frames to detect tampering in frame unit and to ensure the reversibility of the rest data even tampering occurs partially. The numerical simulation experiments on detection precise and acoustic degradation indicate that the proposed scheme satisfied highly variability and reversibility, while the acoustic degradation of stego data is imperceptible on the basis of the ITU-R BS.1387 (PEAQ) standard.We propose and implement a content-based tampering detective steganography scheme using acoustic data with probative value in this paper. The purpose is to verify and identify malicious modification. Content-based hash function SHA-1 is adapted to detect tampering. After transforming data from time-domain to frequency domain using integer Discrete Cosine Transform (int-DCT), the amplitude of the highest frequency domain is expanded to reserve embedding capacity which is necessary for hiding hash value and index table for hiding. Lossless embedding and extraction algorithm ensure this scheme a reversible alternative scheme to meet the requirements of acoustic media with probative value. Hash digest is applied to data units after the original data is divided to frames to detect tampering in frame unit and to ensure the reversibility of the rest data even tampering occurs partially. The numerical simulation experiments on detection precise and acoustic degradation indicate that the proposed scheme satisfied highly variability and reversibility, while the acoustic degradation of stego data is imperceptible on the basis of the ITU-R BS.1387 (PEAQ) standard.

著者

西村 晃 Akira Nishimura

出版者

同志社大学経済学会

雑誌

經濟學論叢 = Keizaigaku-Ronso (The Doshisha University economic review) (ISSN:03873021)

巻号頁・発行日

vol.20, no.1-2, pp.110-138, 1972-03-25

著者

Yasuhiko OHARA Yukihiro KATO Akira NISHIMURA Tsutomu NAKAZAWA

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.124, no.5, pp.675-679, 2015-10-25 (Released:2015-11-04)

参考文献数

20

著者

西村 明 小泉 宣夫 ニシムラ アキラ コイズミ ノブオ Akira Nishimura Nobuo Koizumi

雑誌

東京情報大学研究論集

巻号頁・発行日

vol.7, no.2, pp.79-92, 2004-02-20

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いくつかの種類のディジタルオーディオ機器におけるサンプリングジッター測定の結果を示した。解析信号を用いたジッター測定は、CD-Rメディアの製造メーカの違い、信号のビットパターン、ディジタル信号伝送系、DAC, ADCそしてプレーヤのクロック発振器など、複数の要因が、オーディオ機器の微細なジッター特性に影響を与えていることを示した。ジッター測定を通じて得られた最大のジッター成分振幅は、ジッター周波数2 Hz以上において、2nsを下回った。従来の周波数変動検知実験の結果と比較すると、この程度のジッターが音質に与える影響を聴取者が検知することは困難であると予想される。

著者

Fumiaki Satoh Takayuki Arai Akira Nishimura

出版者

一般社団法人 日本音響学会

雑誌

Acoustical Science and Technology (ISSN:13463969)

巻号頁・発行日

vol.37, no.4, pp.143-147, 2016-07-01 (Released:2016-07-01)

参考文献数

34

被引用文献数

2

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In the Acoustical Society of Japan (ASJ), the Research Committee on Education in Acoustics was established in 1997. Although its history is relatively short in comparison with the Administrative Committee on Education in Acoustics in the Acoustical Society of America (ASA), many activities have been steadily carried out. For example, surveys of syllabi (educational plans of subjects in universities) were made. Demonstration tools used in university classes were also surveyed. The extent of our research was not limited to only universities. Textbooks and teaching materials used in elementary schools, junior high schools, and senior high schools were also researched. Furthermore, activities in cooperation with the National Museum of Nature and Science in Japan have been taking place, including an exhibition and a class with acoustic demonstrations and handicrafts for children. We believe that such activities are very important as social contributions of an academic society. In this review, some of our activities, our discussions, and the like will be introduced.