We present a novel data hiding method for compressed images. The method is designed to minimize the quality loss associated with data embedding into a JPEG image. The described technique uses the objective criterion such as the mean square error and the human visual system based criterion such as the Just Noticable Distortion metric for distortion minimization. The hiding method is designed under the restrictions of the JPEG compression standard to develop new image applications without any modifications or additions to the existing standard. An application example is presented in the thesis. The performance of the technique is examined at different image sizes and resolutions. The cost of hiding in terms of file length extension is examined. Some subjective experiments to determine the zero-perceived distortion hiding capacity are made. An application illustrating the usage of the technique is given. The described application embeds check-bits into JPEG images to facilitate the verification of the sender identity and the authenticity of the transmitted image. In this thesis, we give a list of requirements on the data hiding methods to implement standard compliant applications; design a provably good hiding method operating under these requirements; determine the critical performance points of the method and propose an application based on the method. We have performed some additional research to determine how our system works with high resolution images and existing other well-known algorithms for information hiding. The experiments on high-resolution images have shown that there exists a large embedding capacity for the high resolution images in spite of a loss of embedding density. The performance comparison experiments have shown that the spread spectrum technique offers a competitive but less efficient distortion performance.

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Debugging in the System-on-a-Chip (SoC) environment is a challenge since it was hard to observe their signals on a chip. How to obtain the chip internal signals to help chip designers effective to verify and debug has become an important issue.It is impractical to observe their signals on output pins due to pin number limitation. The conventional solution is to embed a monitor within the hardware for capturing the signals in real time and storing them in a on-chip trace memory. This thesis shows how the embedded multi-resolution AXI Bus Tracer can enable users to achieve the SoC debugging and performance evaluation efficiently, and it can trace the AXI Signals on the AMBA 3.0 AXI environment. Users can dynamically adjust the tracking resolution during the program execution, and we also provide an effective encoding algorithm for compressing the trace data. With our trace analysis software, we provide the detail information ranging from detail signal waveforms to transaction level waveforms, and transfer the trace signals into Value Change Dump (VCD) file. We also show several pie charts to analyze the portion of transfer types. In our work, we provide a synthesizable hardware to embed SOC for capturing signals. Then traced information through decompress and analysis can make users analyze system debugging and performance evaluation.

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With advancing technology, Chip Multi-processor (CMP) architectures have emerged as a viable solution for designing processors. Networks-On-Chip (NOCs) provide a scalable communication method for CMP architectures with increasing numbers of cores. Although there has been significant research on NOC designs for unicast traffic, the research on the multicast router design is still in its infant stage. Considering that one-to-many (multicast) and one-to-all (broadcast) traffic are more common in CMP applications, it is important to design a router providing efficient multicasting. In this thesis, a lookahead multicast routing algorithm with limited area overhead is proposed. This lookahead algorithm reduces network latency by removing the need for a separate routing computation (RC) stage. An efficient area optimization technique is put forward to achieve minimal area overhead for the lookahead RC stage. Also, a novel compression scheme is proposed for multicast packet headers to alleviate their big overhead in large networks. Comprehensive simulation results show that with the new route computation logic design and area overhead optimization, providing lookahead routing in the multicast router only costs less than 20 percent area overhead and this percentage keeps decreasing with larger network sizes. Compared with the basic lookahead routing design, our design can save area by over 50 percent. With header compression and lookahead multicast routing, the network performance can be improved on an average by 22 percent for a (16 x 16) network.

Aluminum (1050) was deformed by plane strain compression (PSC) up to 75% reduction. The total deformation conditions include four temperatures (from 150oC to 300oC) and two strain rates (5¡Ñ10-2s-1 and 5¡Ñ10-4s-1). After the deformation, the specimens were examined by TEM for observing the morphology of the microstructures and measuring various parameters, which includes the sizes and aspect ratios of dislocation cells, as well as the distribution of misorientation angles for dislocation walls.

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Fractal image compression is based on the representation of an image by contractive transforms whose xed points are close to the original image. In the encoding of fractal image compression, most of the time is spent on nding the close match between a range block and a large pool of domain blocks. In this thesis, we use the intra-block variances distributions of domain blocks to reduce the searching space. For nding a close match we need only search the domain blocks whose maximal intra-block variance quadrants are the same as that of the range block in nding a close match. The experiment results show that our algorithm can reduce much encoding time with only slight loss of quality.

The performance and speed of the interframe motion estimation method for sequencial frame sequence compression are the important issues especially in networking application such as video conference and video on demand. In this paper, we proposed a new fast search algorithm for motion estimation on block matching technique called the cocktail search algorithm (CTS). This new algorithm takes advantages of prior search algorithms proposed in the literature and improves at our observations. The experiment results show that the proposed CTS algorithm can provide the better performance and require less computational costs than others. In other words, the CTS can obtain the accurate motion vector efficiently and fast. The fruitful results is achieved by not only holding the original benefit but also constructively improving the existing drawbacks.

In recent years, the internet has been in widespread use and the number of internet subscribers increased quickly. Hence a lot of applications on the network have been developed, multimedia programs especially. Whereas the original video content always takes up considerable storage and transmission time which doesn¡¦t suit for network application, many video compression standards have been drawn up in the literature Due to the temporal redundancy of the video sequences, motion estimation / compensation has been widely used in many interframe video coding protocols to reduce the required bit rates for transmission and storage of video signals by eliminating it, such as the MPEG-1, MPEG-2, H.261 and H.263. The performance and speed of the interframe motion estimation method for video sequence compression are the important issues especially in networking application such as video conference and video on demand. Today all motion estimating method find out the estimating point which has minimal Mean Square Error, and motion compensation aim at estimating error to do JPEG. compression. As everyone knows, JPEG employs DCT to eliminate the correlation of spatial domain. So the best motion estimating point is the point which has the minimal compressed data size. In some alalyses show that over 50% best estimating point do not have the minimal compressed data size. So the factor which effects the compressed data size is correlation coefficient and not MSE. Hence, we try to define a new criterion for motion estimation which can get better motion compensation with less compressing bit rate. To reach this goal, we try to find out the correlation among the motion compensation as the new criterion for motion estimation.