Randomly selecting 8 × 8 host blocks in big-blocks for data embedding, YASS, a recently developed advanced stegano-graphic scheme makes these blocks not coincident with the 8×8 grids used in JPEG compression...
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Randomly selecting 8 × 8 host blocks in big-blocks for data embedding, YASS, a recently developed advanced stegano-graphic scheme makes these blocks not coincident with the 8×8 grids used in JPEG compression. As a result, it effectively invalidates the self-calibration technique used in modern steganaly-sis. However, the randomization is not sufficient enough, i.e., some positions in an image are possible to hold host blocks and some are definitely not. Based on this observation, the newly developed specific steganalyzer can effectively defeat YASS. In this paper, a new steganographic scheme is presented. Through randomizing the size and position of each big-block, our improved steganographic method makes almost every position possible to hold a host block, which has been verified by our statistical analysis. Consequently, the proposed scheme can survive the attack made by the specific steganalyzer. Experimental results have demonstrated that the detection rate achieved by the specific steganalyzer on our proposed method is less than 58%, while that on YASS is about 95% and above.
This paper outlines a scheme for compressing EEG signals based on the JPEG2000 image compression algorithm. Such a scheme could be used to compress signals in an ambulatory system, where low-power operation is importa...
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This paper outlines a scheme for compressing EEG signals based on the JPEG2000 image compression algorithm. Such a scheme could be used to compress signals in an ambulatory system, where low-power operation is important to conserve battery life; therefore, a high compression ratio is desirable to reduce the amount of data that needs to be transmitted. The JPEG2000 specification makes use of the wavelet transform, which can be efficiently implemented in embedded systems. The standard was broken down to its core components and adapted for use on EEG signals with additional compression steps added. Variations on the components were tested to maximize compression ratio (CR) while maintaining a low percentage root-mean-squared difference (PRD) and minimize power requirements. Initial tests indicate that the algorithm performs well in relation to other EEG compression methods proposed in the literature.
This paper introduces a new watermarking algorithm based on discrete chaotic iterations. After defining some coefficients deduced from the description of the carrier medium, chaotic discrete iterations are used to mix...
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This paper introduces a new watermarking algorithm based on discrete chaotic iterations. After defining some coefficients deduced from the description of the carrier medium, chaotic discrete iterations are used to mix the watermark and to embed it in the carrier medium. It can be proved that this procedure generates topological chaos, which ensures that desired properties of a watermarking algorithm are satisfied.
Multiple Descriptions (MDs) source coding is a method to overcome unexpected information loss in a diversity system such as the internet, or a wireless network. In case that the information can suffer loss and still b...
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Multiple Descriptions (MDs) source coding is a method to overcome unexpected information loss in a diversity system such as the internet, or a wireless network. In case that the information can suffer loss and still be intelligible, like audio or video, MD is a way to take full advantage of the diversity in the system and provide graceful degradation. Standards-compliant MD coding targeting widely used compression standards, such as JPEG and MPEG, have so far however received little attention in the literature. A recently proposed scheme of MD coding by dithered Delta-Sigma Quantization (DSQ) utilizes oversampling in order to accomplish diversity, and noise shaping to control the distortion-versus-loss trade off at any fixed rate. In this work we implement a DSQ-based MD compression scheme for images/videos working in the discrete cosine transform (DCT) domain. The MD encoder and decoder consist of a standard JPEG/MPEG core, with additional processing and control. We show promising numerical results under various scenarios.
In this paper we propose a blind wavelet-based logo watermarking scheme focusing on resisting to cropping. The binary logo is embedded in the LL 2 sub-band of host image, using quantization technique. For increasing ...
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ISBN:
(纸本)9781424475421
In this paper we propose a blind wavelet-based logo watermarking scheme focusing on resisting to cropping. The binary logo is embedded in the LL 2 sub-band of host image, using quantization technique. For increasing robustness of proposed algorithm two dimensional parity bits are added to the binary logo. Experimental results show that the proposed watermarking method can resist not only cropping attack, but also some common signal processing attacks, such as JPEG compression, average and median filtering, rotation and scaling.
In this paper, a new generic generating algorithm for rank n integer DCT transform radix is proposed. The relation of amounts of coefficients in radix and rank of matrix and an generic generating algorithm for rank n ...
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ISBN:
(纸本)9781424451623;9781424451616
In this paper, a new generic generating algorithm for rank n integer DCT transform radix is proposed. The relation of amounts of coefficients in radix and rank of matrix and an generic generating algorithm for rank n (n=2 k ,k>0) integer DCT transform radix are found and proved in this paper based on theory of integer DCT and characteristic of cosine function. Through reordering variations of coefficient, the mid-polynomials have strong laws. The group of polynomials in N variable is resolved by design a N-digits with M as radix implementing N-loops. The experimental result show that the algorithm can find all valid radix for n×n (n=2 k ,k>0) integer DCT if computers power enough.
Health care is a critical social issue in all over the world nowadays, especially in small town or rural areas where expert doctors, nurses, electronic equipments and other infrastructures are not adequate. As a promi...
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Health care is a critical social issue in all over the world nowadays, especially in small town or rural areas where expert doctors, nurses, electronic equipments and other infrastructures are not adequate. As a promising approach to address this issue, telemedicine has received much attention. Telemedicine is a multimedia application where real time video, audio, text, graphics and vital signs are transmitted through the existing telecommunication facilities. Video data is the most dominant part in terms of information contribution of telemedicine electronic signal. However it requires huge bandwidth among the other components of signals. Reducing the transmission bit rates concomitantly obtaining the acceptable video quality is still a big challenge for researchers in telemedicine applications in real-time through the band-limited wired or wireless channels, especially through the latter one which accommodates only very low-bit transmission. This paper introduces an advanced video transmission platform based on H.264 compression standard. The efficiency and effectiveness of the presented platform are demonstrated by experimental results.
Wireless networks have been rapidly developing in recent years. The main objective of this paper is to propose a video transcoding scheme to provide the scalable video data over wireless transmission applications. Mor...
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Wireless networks have been rapidly developing in recent years. The main objective of this paper is to propose a video transcoding scheme to provide the scalable video data over wireless transmission applications. Moreover video transcoding methods are required for high speed. So we used the pixel-domain close-loop video transcoding construction with reusing decoding information to output H.264 SVC bitstream. Finally, experimental results demonstrated the proposed scheme can reduce the computation of the transcoding process and maintain the output video quality. Our transcoder represents a practical solution which enables rich media communication in heterogeneous mobile environments.
To meet different security demands, this work proposes an alterable-capacity algorithm for JPEG images. First, the original image is divided into 8×8 blocks. The authentication watermarks of each block are comput...
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To meet different security demands, this work proposes an alterable-capacity algorithm for JPEG images. First, the original image is divided into 8×8 blocks. The authentication watermarks of each block are computed by its quantized DCT coefficients and the secret-matrix generated by user key, where the size of secret-matrix depends on the watermark capacity. The authentication watermarks of each block are embedded into the middle quantized DCT coefficients in other blocks. The validity of the test block is determined by comparing the number of inconsistent blocks in eight neighbor blocks of test block with the average of that of its mapping blocks. To further enhance the performance of tamper detection, the invalid block will be set valid if there are three and less invalid blocks in its eight neighbor blocks. We also discuss that the interaction among watermark capacity, invisibility and tamper detection performance. Experimental results show that the proposed scheme outperforms the literature [8] in tamper detection with the same watermark capacity.
The robustness of a biometric Identity Verification (IV) system is best evaluated by monitoring its behavior under impostor attacks. Such attacks may include the transformation of one or multiple biometric modalities ...
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The robustness of a biometric Identity Verification (IV) system is best evaluated by monitoring its behavior under impostor attacks. Such attacks may include the transformation of one or multiple biometric modalities typically face and voice. In this paper, we evaluate the effects of transforming both the face and the voice of a speaker on an IV system. Results of imposture experiments on the BANCA talking-face database show an increase in the error rate of the audiovisual IV system, which indicates a higher acceptance rate of the claimed identities. Results are reported on transformation of the speech and visual signals (MixTrans for speech, and TPS warping animation for face) For both types of forgeries, the verification system accepted more impostors.
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