30 research outputs found
Secure covert communications over streaming media using dynamic steganography
Streaming technologies such as VoIP are widely embedded into commercial and industrial applications, so it is imperative to address data security issues before the problems get really serious. This thesis describes a theoretical and experimental investigation of secure covert communications over streaming media using dynamic steganography. A covert VoIP communications system was developed in C++ to enable the implementation of the work being carried out.
A new information theoretical model of secure covert communications over streaming media was constructed to depict the security scenarios in streaming media-based steganographic systems with passive attacks. The model involves a stochastic process that models an information source for covert VoIP communications and the theory of hypothesis testing that analyses the adversaryâs detection performance.
The potential of hardware-based true random key generation and chaotic interval selection for innovative applications in covert VoIP communications was explored. Using the read time stamp counter of CPU as an entropy source was designed to generate true random numbers as secret keys for streaming media steganography. A novel interval selection algorithm was devised to choose randomly data embedding locations in VoIP streams using random sequences generated from achaotic process.
A dynamic key updating and transmission based steganographic algorithm that includes a one-way cryptographical accumulator integrated into dynamic key exchange for covert VoIP communications, was devised to provide secure key exchange for covert communications over streaming media. The discrete logarithm problem in mathematics and steganalysis using t-test revealed the algorithm has the advantage of being the most solid method of key distribution over a public channel.
The effectiveness of the new steganographic algorithm for covert communications over streaming media was examined by means of security analysis, steganalysis using non parameter Mann-Whitney-Wilcoxon statistical testing, and performance and robustness measurements. The algorithm achieved the average data embedding rate of 800 bps, comparable to other related algorithms. The results indicated that the algorithm has no or little impact on real-time VoIP communications in terms of speech quality (< 5% change in PESQ with hidden data), signal distortion (6% change in SNR after steganography) and imperceptibility, and it is more secure and effective in addressing the security problems than other related algorithms
Digital Watermarking for Verification of Perception-based Integrity of Audio Data
In certain application fields digital audio recordings contain sensitive content. Examples are historical archival material in public archives that preserve our cultural heritage, or digital evidence in the context of law enforcement and civil proceedings. Because of the powerful capabilities of modern editing tools for multimedia such material is vulnerable to doctoring of the content and forgery of its origin with malicious intent. Also inadvertent data modification and mistaken origin can be caused by human error. Hence, the credibility and provenience in terms of an unadulterated and genuine state of such audio content and the confidence about its origin are critical factors.
To address this issue, this PhD thesis proposes a mechanism for verifying the integrity and authenticity of digital sound recordings. It is designed and implemented to be insensitive to common post-processing operations of the audio data that influence the subjective acoustic perception only marginally (if at all). Examples of such operations include lossy compression that maintains a high sound quality of the audio media, or lossless format conversions. It is the objective to avoid de facto false alarms that would be expectedly observable in standard crypto-based authentication protocols in the presence of these legitimate post-processing. For achieving this, a feasible combination of the techniques of digital watermarking and audio-specific hashing is investigated.
At first, a suitable secret-key dependent audio hashing algorithm is developed. It incorporates and enhances so-called audio fingerprinting technology from the state of the art in contentbased audio identification. The presented algorithm (denoted as ârMACâ message authentication code) allows âperception-basedâ verification of integrity. This means classifying integrity breaches as such not before they become audible. As another objective, this rMAC is embedded and stored silently inside the audio media by means of audio watermarking technology. This approach allows maintaining the authentication code across the above-mentioned admissible post-processing operations and making it available for integrity verification at a later date. For this, an existent secret-key ependent audio watermarking algorithm is used and enhanced in this thesis work.
To some extent, the dependency of the rMAC and of the watermarking processing from a secret key also allows authenticating the origin of a protected audio. To elaborate on this security aspect, this work also estimates the brute-force efforts of an adversary attacking this combined rMAC-watermarking approach. The experimental results show that the proposed method provides a good distinction and classification
performance of authentic versus doctored audio content. It also allows the temporal localization of audible data modification within a protected audio file. The experimental evaluation finally provides recommendations about technical configuration settings of the combined watermarking-hashing approach.
Beyond the main topic of perception-based data integrity and data authenticity for audio, this PhD work provides new general findings in the fields of audio fingerprinting and digital watermarking. The main contributions of this PhD were published and presented mainly at conferences about multimedia security. These publications were cited by a number of other authors and hence had some impact on their works
Integration of biometrics and steganography: A comprehensive review
The use of an individualâs biometric characteristics to advance authentication and verification technology beyond the current dependence on passwords has been the subject of extensive research for some time. Since such physical characteristics cannot be hidden from the public eye, the security of digitised biometric data becomes paramount to avoid the risk of substitution or replay attacks. Biometric systems have readily embraced cryptography to encrypt the data extracted from the scanning of anatomical features. Significant amounts of research have also gone into the integration of biometrics with steganography to add a layer to the defence-in-depth security model, and this has the potential to augment both access control parameters and the secure transmission of sensitive biometric data. However, despite these efforts, the amalgamation of biometric and steganographic methods has failed to transition from the research lab into real-world applications. In light of this review of both academic and industry literature, we suggest that future research should focus on identifying an acceptable level steganographic embedding for biometric applications, securing exchange of steganography keys, identifying and address legal implications, and developing industry standards
An improvement of RGB color image watermarking technique using ISB stream bit and Hadamard matrix
In the past half century, the advancement of internet technology has been rapid and widespread. The innovation provides an efficient platform for human communication and other digital applications. Nowadays, everyone can easily access, copy, modify and distribute digital contents for personal or commercial gains. Therefore, a good copyright protection is required to discourage the illicit activities. On way is to watermark the assets by embedding an owner's identity which could later on be used for authentication. Thus far, many watermarking techniques have been proposed which focus on improving three standard measures, visual quality or imperceptibility, robustness and capacity. Although their performances are encouraging, there are still plenty of rooms for improvements. Thus, this study proposes a new watermarking technique using Least Significant Bit (LSB) insertion approach coupled with Hadamard matrix. The technique involves four main stages: Firstly, the cover image is decomposed into three separate channels, Red, Green and Blue. Secondly, the Blue channel is chosen and converted into an eight bit stream. Thirdly, the second least signification bit is selected from the bit stream for embedding. In order to increase the imperceptibility a Hadamard matrix is used to find the best pixels of the cover image for the embedding task. Experimental results on standard dataset have revealed that average PSNR value is greater than 58db, which indicates the watermarked image is visually identical to its original. However, the proposed technique suffers from Gaussian and Poisson noise attacks
Application and Theory of Multimedia Signal Processing Using Machine Learning or Advanced Methods
This Special Issue is a book composed by collecting documents published through peer review on the research of various advanced technologies related to applications and theories of signal processing for multimedia systems using ML or advanced methods. Multimedia signals include image, video, audio, character recognition and optimization of communication channels for networks. The specific contents included in this book are data hiding, encryption, object detection, image classification, and character recognition. Academics and colleagues who are interested in these topics will find it interesting to read
Applications de la reprĂ©sentation parcimonieuse perceptuelle par graphe de dĂ©charges (Spikegramme) pour la protection du droit dâauteur des signaux sonores
Chaque année, le piratage mondial de la musique coûte plusieurs milliards de dollars en
pertes Ă©conomiques, pertes dâemplois et pertes de gains des travailleurs ainsi que la perte
de millions de dollars en recettes fiscales. La plupart du piratage de la musique est dĂ»
à la croissance rapide et à la facilité des technologies actuelles pour la copie, le partage,
la manipulation et la distribution de données musicales [Domingo, 2015], [Siwek, 2007].
Le tatouage des signaux sonores a été proposé pour protéger les droit des auteurs et
pour permettre la localisation des instants oĂč le signal sonore a Ă©tĂ© falsifiĂ©. Dans cette
thĂšse, nous proposons dâutiliser la reprĂ©sentation parcimonieuse bio-inspirĂ©e par graphe de
décharges (spikegramme), pour concevoir une nouvelle méthode permettant la localisation
de la falsification dans les signaux sonores. Aussi, une nouvelle méthode de protection du
droit dâauteur. Finalement, une nouvelle attaque perceptuelle, en utilisant le spikegramme,
pour attaquer des systĂšmes de tatouage sonore.
Nous proposons tout dâabord une technique de localisation des falsifications (âtamperingâ)
des signaux sonores. Pour cela nous combinons une méthode à spectre étendu modifié
(âmodified spread spectrumâ, MSS) avec une reprĂ©sentation parcimonieuse. Nous utilisons
une technique de poursuite perceptive adaptée (perceptual marching pursuit, PMP [Hossein
Najaf-Zadeh, 2008]) pour générer une représentation parcimonieuse (spikegramme) du
signal sonore dâentrĂ©e qui est invariante au dĂ©calage temporel [E. C. Smith, 2006] et qui
prend en compte les phĂ©nomĂšnes de masquage tels quâils sont observĂ©s en audition. Un code
dâauthentification est insĂ©rĂ© Ă lâintĂ©rieur des coefficients de la reprĂ©sentation en spikegramme.
Puis ceux-ci sont combinĂ©s aux seuils de masquage. Le signal tatouĂ© est resynthĂ©tisĂ© Ă
partir des coefficients modifiés, et le signal ainsi obtenu est transmis au décodeur. Au
dĂ©codeur, pour identifier un segment falsifiĂ© du signal sonore, les codes dâauthentification de
tous les segments intacts sont analysĂ©s. Si les codes ne peuvent ĂȘtre dĂ©tectĂ©s correctement,
on sait quâalors le segment aura Ă©tĂ© falsifiĂ©. Nous proposons de tatouer selon le principe
Ă spectre Ă©tendu (appelĂ© MSS) afin dâobtenir une grande capacitĂ© en nombre de bits de
tatouage introduits. Dans les situations oĂč il y a dĂ©synchronisation entre le codeur et le
dĂ©codeur, notre mĂ©thode permet quand mĂȘme de dĂ©tecter des piĂšces falsifiĂ©es. Par rapport
Ă lâĂ©tat de lâart, notre approche a le taux dâerreur le plus bas pour ce qui est de dĂ©tecter
les piĂšces falsifiĂ©es. Nous avons utilisĂ© le test de lâopinion moyenne (âMOSâ) pour mesurer
la qualité des systÚmes tatoués. Nous évaluons la méthode de tatouage semi-fragile par
le taux dâerreur (nombre de bits erronĂ©s divisĂ© par tous les bits soumis) suite Ă plusieurs
attaques. Les résultats confirment la supériorité de notre approche pour la localisation des
piÚces falsifiées dans les signaux sonores tout en préservant la qualité des signaux.
Ensuite nous proposons une nouvelle technique pour la protection des signaux sonores.
Cette technique est basée sur la représentation par spikegrammes des signaux sonores
et utilise deux dictionnaires (TDA pour Two-Dictionary Approach). Le spikegramme est
utilisé pour coder le signal hÎte en utilisant un dictionnaire de filtres gammatones. Pour
le tatouage, nous utilisons deux dictionnaires différents qui sont sélectionnés en fonction
du bit dâentrĂ©e Ă tatouer et du contenu du signal. Notre approche trouve les gammatones appropriĂ©s (appelĂ©s noyaux de tatouage) sur la base de la valeur du bit Ă tatouer, et
incorpore les bits de tatouage dans la phase des gammatones du tatouage. De plus, il
est montrĂ© que la TDA est libre dâerreur dans le cas dâaucune situation dâattaque. Il est
dĂ©montrĂ© que la dĂ©corrĂ©lation des noyaux de tatouage permet la conception dâune mĂ©thode
de tatouage sonore trĂšs robuste.
Les expériences ont montré la meilleure robustesse pour la méthode proposée lorsque le
signal tatoué est corrompu par une compression MP3 à 32 kbits par seconde avec une
charge utile de 56.5 bps par rapport à plusieurs techniques récentes. De plus nous avons
étudié la robustesse du tatouage lorsque les nouveaux codec USAC (Unified Audion and
Speech Coding) à 24kbps sont utilisés. La charge utile est alors comprise entre 5 et 15 bps.
Finalement, nous utilisons les spikegrammes pour proposer trois nouvelles méthodes
dâattaques. Nous les comparons aux mĂ©thodes rĂ©centes dâattaques telles que 32 kbps MP3
et 24 kbps USAC. Ces attaques comprennent lâattaque par PMP, lâattaque par bruit
inaudible et lâattaque de remplacement parcimonieuse. Dans le cas de lâattaque par PMP,
le signal de tatouage est représenté et resynthétisé avec un spikegramme. Dans le cas de
lâattaque par bruit inaudible, celui-ci est gĂ©nĂ©rĂ© et ajoutĂ© aux coefficients du spikegramme.
Dans le cas de lâattaque de remplacement parcimonieuse, dans chaque segment du signal,
les caractĂ©ristiques spectro-temporelles du signal (les dĂ©charges temporelles ;âtime spikesâ)
se trouvent en utilisant le spikegramme et les spikes temporelles et similaires sont remplacés
par une autre.
Pour comparer lâefficacitĂ© des attaques proposĂ©es, nous les comparons au dĂ©codeur du
tatouage Ă spectre Ă©tendu. Il est dĂ©montrĂ© que lâattaque par remplacement parcimonieux
réduit la corrélation normalisée du décodeur de spectre étendu avec un plus grand facteur
par rapport Ă la situation oĂč le dĂ©codeur de spectre Ă©tendu est attaquĂ© par la transformation MP3 (32 kbps) et 24 kbps USAC.Abstract : Every year global music piracy is making billion dollars of economic, job, workersâ earnings
losses and also million dollars loss in tax revenues. Most of the music piracy is because of
rapid growth and easiness of current technologies for copying, sharing, manipulating and
distributing musical data [Domingo, 2015], [Siwek, 2007]. Audio watermarking has been
proposed as one approach for copyright protection and tamper localization of audio signals
to prevent music piracy. In this thesis, we use the spikegram- which is a bio-inspired sparse
representation- to propose a novel approach to design an audio tamper localization method
as well as an audio copyright protection method and also a new perceptual attack against
any audio watermarking system.
First, we propose a tampering localization method for audio signal, based on a Modified
Spread Spectrum (MSS) approach. Perceptual Matching Pursuit (PMP) is used to compute
the spikegram (which is a sparse and time-shift invariant representation of audio signals) as
well as 2-D masking thresholds. Then, an authentication code (which includes an Identity
Number, ID) is inserted inside the sparse coefficients. For high quality watermarking, the
watermark data are multiplied with masking thresholds. The time domain watermarked
signal is re-synthesized from the modified coefficients and the signal is sent to the decoder.
To localize a tampered segment of the audio signal, at the decoder, the IDâs associated to
intact segments are detected correctly, while the ID associated to a tampered segment is
mis-detected or not detected. To achieve high capacity, we propose a modified version of
the improved spread spectrum watermarking called MSS (Modified Spread Spectrum). We
performed a mean opinion test to measure the quality of the proposed watermarking system.
Also, the bit error rates for the presented tamper localization method are computed under
several attacks. In comparison to conventional methods, the proposed tamper localization
method has the smallest number of mis-detected tampered frames, when only one frame
is tampered. In addition, the mean opinion test experiments confirms that the proposed
method preserves the high quality of input audio signals.
Moreover, we introduce a new audio watermarking technique based on a kernel-based
representation of audio signals. A perceptive sparse representation (spikegram) is combined
with a dictionary of gammatone kernels to construct a robust representation of sounds.
Compared to traditional phase embedding methods where the phase of signalâs Fourier
coefficients are modified, in this method, the watermark bit stream is inserted by modifying
the phase of gammatone kernels. Moreover, the watermark is automatically embedded only
into kernels with high amplitudes where all masked (non-meaningful) gammatones have
been already removed. Two embedding methods are proposed, one based on the watermark
embedding into the sign of gammatones (one dictionary method) and another one based
on watermark embedding into both sign and phase of gammatone kernels (two-dictionary
method). The robustness of the proposed method is shown against 32 kbps MP3 with
an embedding rate of 56.5 bps while the state of the art payload for 32 kbps MP3 robust
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watermarking is lower than 50.3 bps. Also, we showed that the proposed method is robust
against unified speech and audio codec (24 kbps USAC, Linear predictive and Fourier
domain modes) with an average payload of 5 â 15 bps. Moreover, it is shown that the
proposed method is robust against a variety of signal processing transforms while preserving
quality.
Finally, three perceptual attacks are proposed in the perceptual sparse domain using
spikegram. These attacks are called PMP, inaudible noise adding and the sparse replacement
attacks. In PMP attack, the host signals are represented and re-synthesized with
spikegram. In inaudible noise attack, the inaudible noise is generated and added to the
spikegram coefficients. In sparse replacement attack, each specific frame of the spikegram
representation - when possible - is replaced with a combination of similar frames located
in other parts of the spikegram. It is shown than the PMP and inaudible noise attacks
have roughly the same efficiency as the 32 kbps MP3 attack, while the replacement attack
reduces the normalized correlation of the spread spectrum decoder with a greater factor
than when attacking with 32 kbps MP3 or 24 kbps unified speech and audio coding (USAC)
Resiliency Assessment and Enhancement of Intrinsic Fingerprinting
Intrinsic fingerprinting is a class of digital forensic technology that can detect traces left in digital multimedia data in order to reveal data processing history and determine data integrity. Many existing intrinsic fingerprinting schemes have implicitly assumed favorable operating conditions whose validity may become uncertain in reality. In order to establish intrinsic fingerprinting as a credible approach to digital multimedia authentication, it is important to understand and enhance its resiliency under unfavorable scenarios.
This dissertation addresses various resiliency aspects that can appear in a broad range of intrinsic fingerprints. The first aspect concerns intrinsic fingerprints that are designed to identify a particular component in the processing chain. Such fingerprints are potentially subject to changes due to input content variations and/or post-processing, and it is desirable to ensure their identifiability in such situations. Taking an image-based intrinsic fingerprinting technique for source camera model identification as a representative example, our investigations reveal that the fingerprints have a substantial dependency on image content. Such dependency limits the achievable identification accuracy, which is penalized by a mismatch between training and testing image content. To mitigate such a mismatch, we propose schemes to incorporate image content into training image selection and significantly improve the identification performance. We also consider the effect of post-processing against intrinsic fingerprinting, and study source camera identification based on imaging noise extracted from low-bit-rate compressed videos. While such compression reduces the fingerprint quality, we exploit different compression levels within the same video to achieve more efficient and accurate identification.
The second aspect of resiliency addresses anti-forensics, namely, adversarial actions that intentionally manipulate intrinsic fingerprints. We investigate the cost-effectiveness of anti-forensic operations that counteract color interpolation identification. Our analysis pinpoints the inherent vulnerabilities of color interpolation identification, and motivates countermeasures and refined anti-forensic strategies. We also study the anti-forensics of an emerging space-time localization technique for digital recordings based on electrical network frequency analysis. Detection schemes against anti-forensic operations are devised under a mathematical framework. For both problems, game-theoretic approaches are employed to characterize the interplay between forensic analysts and adversaries and to derive optimal strategies.
The third aspect regards the resilient and robust representation of intrinsic fingerprints for multiple forensic identification tasks. We propose to use the empirical frequency response as a generic type of intrinsic fingerprint that can facilitate the identification of various linear and shift-invariant (LSI) and non-LSI operations
DRONE DELIVERY OF CBNRECy â DEW WEAPONS Emerging Threats of Mini-Weapons of Mass Destruction and Disruption (WMDD)
Drone Delivery of CBNRECy â DEW Weapons: Emerging Threats of Mini-Weapons of Mass Destruction and Disruption (WMDD) is our sixth textbook in a series covering the world of UASs and UUVs. Our textbook takes on a whole new purview for UAS / CUAS/ UUV (drones) â how they can be used to deploy Weapons of Mass Destruction and Deception against CBRNE and civilian targets of opportunity. We are concerned with the future use of these inexpensive devices and their availability to maleficent actors. Our work suggests that UASs in air and underwater UUVs will be the future of military and civilian terrorist operations. UAS / UUVs can deliver a huge punch for a low investment and minimize human casualties.https://newprairiepress.org/ebooks/1046/thumbnail.jp