In this paper, a programmable 2-D DWT system architecture designed for the JPEG2000 standard is proposed. The proposed system architecture, developed through an iterative design space exploration methodology using Alt...
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In this paper, a programmable 2-D DWT system architecture designed for the JPEG2000 standard is proposed. The proposed system architecture, developed through an iterative design space exploration methodology using Altera's C2H compiler, provides a significant 2-D DWT performance improvement when compared to an optimized 2-D DWT software implementation and is capable of real-time video processing performance for high resolution grayscale images up to 1280 × 720 (720p) when synthesized and benchmarked in an Altera DE3 Stratix III FPGA board.
When digital forgery is introduced in a digital images, in order to create a convincing match, it always includes operation of scaling, rotation or skewing, which procedures typically require resampling and interpolat...
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When digital forgery is introduced in a digital images, in order to create a convincing match, it always includes operation of scaling, rotation or skewing, which procedures typically require resampling and interpolation step. However, the resampling detection is always severely affected by the blocking artifacts introduced by JPEG compression. In order to solve this problem, in this paper an effective method has been proposed to distinguish the periodicity introduced by resampling and JPEG compression. At first, the probability map of an image was obtained by using the expectation-maximization algorithm. Then, it was Fourier-transformed and matched with affine-transform templates and a scaled JPEG template to detect whether the image was resampled, JPEG-compressed or both of them. Experimental results are provided to show the given method is dependable and effective in different kinds of digital tampering when resampling and JPEG compression occurred. Moreover, compared to the existed methods, better results are obtained by us.
Real time video streaming suffers from lost, delayed, and corrupted frames due to the transmission over error prone channels. As an effect of that, the user may notice a frozen picture in their screen. In this work, w...
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Real time video streaming suffers from lost, delayed, and corrupted frames due to the transmission over error prone channels. As an effect of that, the user may notice a frozen picture in their screen. In this work, we propose a technique to eliminate the frozen video and provide a satisfactory quality to the mobile viewer by splitting the video frames into sub-frames. The multiple descriptions coding (MDC) is used to generate multiple bitstreams based on frame splitting and transmitted over multichannels. We evaluate our approach by using mean opinion score (MOS) measurements. MOS is used to evaluate our scenarios where the users observe three levels of frame losses for real time video streaming. The results show that our technique significantly improves the video smoothness on the mobile device in the presence of frame losses during the transmission.
Based on the image edges non-changing characteristic in image format transformation, a new digital watermarking algorithm for huge index image is proposed. The watermarking information was embedded in edges by adjusti...
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Based on the image edges non-changing characteristic in image format transformation, a new digital watermarking algorithm for huge index image is proposed. The watermarking information was embedded in edges by adjusting the edge pixels; therefore, the algorithm is robust against the lossless image format transformation. The experimental results show that the proposed algorithm has perfect Robustness against the lossless image format transformation and good transparency.
For years, several intra-frame encoding methods such as AC/DC prediction used in MPEG-4 and multiple modes intra predication used in H.264 were proposed and the above methods made more efficient compress performance. ...
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For years, several intra-frame encoding methods such as AC/DC prediction used in MPEG-4 and multiple modes intra predication used in H.264 were proposed and the above methods made more efficient compress performance. But compared with inter-frame, the performance still need improved. So, referring to the experience of inter frame compress technique, a novel intra-frame encoding method based on spatial decomposition is proposed in this paper. From experimental data, it can be seen that the proposed algorithm improves subjective nature and increases 0.5-2dB while with similar bitrates compared with the previous methods.
The rapid advances in multimedia and e-learning technologies let us present text, music, video and oral instruction on computers in more vivid ways. The problem is that learning environment has just single information...
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The rapid advances in multimedia and e-learning technologies let us present text, music, video and oral instruction on computers in more vivid ways. The problem is that learning environment has just single information media. That does not include multimedia data and does not give interesting for user. This paper introduces a new e-learning model which supports the harmonized media based on technologies to create and synchronize for multimedia presentation. One of the fundamental concepts of technologies is a recommendation engine based on semantics analysis. For the harmonized media, MPEG-21 Digital Item Declaration is applied to the modeling of synchronized presentation with multi information media.
Video transmission over IP networks requires appropriate conditions of quality of service, in order to ensure the integrity of the image, which still represents a challenge to be overcome in wireless mesh networks due...
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Video transmission over IP networks requires appropriate conditions of quality of service, in order to ensure the integrity of the image, which still represents a challenge to be overcome in wireless mesh networks due to traffic capacity limitations inherent to its architecture. In this work we evaluate the performance of high-resolution video over multi-hop mesh networks and we propose a suitable GOP size for encoding video to be streamed, based on traffic conditions to minimize the loss of quality. Experiments were carried out in a wireless mesh network planned for real testing within a 1500m2 area of the main UFAM campus, using the IEEE 802.11a and 802.11n network standards.
In this paper, we propose a novel Chinese Remainder Theorem (CRT) based watermarking scheme that works in the Discrete Cosine transform (DCT) domain. We first reviewed a Singular Value Decomposition (SVD) based waterm...
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In this paper, we propose a novel Chinese Remainder Theorem (CRT) based watermarking scheme that works in the Discrete Cosine transform (DCT) domain. We first reviewed a Singular Value Decomposition (SVD) based watermarking scheme followed by an existing CRT based watermarking scheme that works in the spatial domain and their shortcomings are highlighted. The proposed CRT based scheme is more resistant to different types of attacks, particularly to JPEG compression; in addition, it improves the security feature of the watermarking scheme. Experimental results have shown that the proposed scheme makes the watermark perceptually invisible and has better robustness to common image manipulation techniques such as JPEG compression, brightening and sharpening effects compared to the spatial domain based CRT scheme; in addition, its computational complexity is much lower than the SVD-based scheme.
This paper presents a leakage efficient instruction TLB (Translation Lookaside Buffer) design for embedded processors. The key observation is that when programs enter a physical page following instructions tend to be ...
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ISBN:
(纸本)9781424476121
This paper presents a leakage efficient instruction TLB (Translation Lookaside Buffer) design for embedded processors. The key observation is that when programs enter a physical page following instructions tend to be fetched from the same page for a rather long time. Thus, by employing a small storage structure which stores the recent address-translation information, the TLB access frequency can be drastically decreased and the instruction TLB can be turned into the low leakage mode with the dual voltage supply technique. Based on such a design philosophy, three different implementation policies are proposed. Evaluation results with eight MiBench programs show that the proposed design can reduce the leakage power of the instruction TLB by 50% on average, with only 0.01% performance degradation.
This paper presents novel algorithm-specific techniques to mitigate the effects of failures in SRAM memory caused by voltage scaling and random dopant fluctuations in scaled technologies. We focus on JPEG2000 as a cas...
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This paper presents novel algorithm-specific techniques to mitigate the effects of failures in SRAM memory caused by voltage scaling and random dopant fluctuations in scaled technologies. We focus on JPEG2000 as a case study. We propose three techniques that exploit the fact that the high frequency subband outputs of the discrete wavelet transform (DWT) have small dynamic range and so errors in the most significant bits can be identified and corrected easily. These schemes do not require any additional memory and have low circuit overhead. We also study several error control coding schemes that are effective in combating errors when the memory failure rates are low. We compare the PSNR versus compression rate performance of the proposed schemes for different memory failure rates. Simulation results show that for high bit error rates (10 -2 ), the error control coding techniques are not effective and that the algorithm-specific techniques can improve the PSNR quality of up to 10dB higher compared to that of the no-correction case.
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