Wavelets and Imaging Informatics: A Review of the Literature

AbstractModern medicine is a field that has been revolutionized by the emergence of computer and imaging technology. It is increasingly difficult, however, to manage the ever-growing enormous amount of medical imaging information available in digital formats. Numerous techniques have been developed to make the imaging information more easily accessible and to perform analysis automatically. Among these techniques, wavelet transforms have proven prominently useful not only for biomedical imaging but also for signal and image processing in general. Wavelet transforms decompose a signal into frequency bands, the width of which are determined by a dyadic scheme. This particular way of dividing frequency bands matches the statistical properties of most images very well. During the past decade, there has been active research in applying wavelets to various aspects of imaging informatics, including compression, enhancements, analysis, classification, and retrieval. This review represents a survey of the most significant practical and theoretical advances in the field of wavelet-based imaging informatics

Progressive transmission of medical images

A novel adaptive source-channel coding scheme for progressive transmission of medical images with a feedback system is therefore proposed in this dissertation. The overall design includes Discrete Wavelet Transform (DWT), Embedded Zerotree Wavelet (EZW) coding, Joint Source-Channel Coding (JSCC), prioritization of region of interest (RoI), variability of parity length based on feedback, and the corresponding hardware design utilising Simulink. The JSCC can achieve an efficient transmission by incorporating unequal error projection (UEP) and rate allocation. An algorithm is also developed to estimate the number of erroneous data in the receiver. The algorithm detects the address in which the number of symbols for each subblock is indicated, and reassigns an estimated correct data according to a decision making criterion, if error data is detected. The proposed system has been designed based on Simulink which can be used to generate netlist for portable devices. A new compression method called Compressive Sensing (CS) is also revisited in this work. CS exhibits many advantages in comparison with EZW based on our experimental results. DICOM JPEG2000 is an efficient coding standard for lossy or lossless multi-component image coding. However, it does not provide any mechanism for automatic RoI definition, and is more complex compared to our proposed scheme. The proposed system significantly reduces the transmission time, lowers computation cost, and maintains an error-free state in the RoI with regards to the above provided features. A MATLAB-based TCP/IP connection is established to demonstrate the efficacy of the proposed interactive and adaptive progressive transmission system. The proposed system is simulated for both binary and symmetric channel (BSC) and Rayleigh channel. The experimental results confirm the effectiveness of the design.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Rate Efficient Wireless Image Transmission using MIMO-OFDM

In this paper, we propose a rate efficient JPEG 2000 image transmission system over hybrid wireless networks using MIMO-OFDM. The objective is to minimize the expected end-to-end distortion given the rate constraint, which is achieved by jointly adjusting source coding schemes and channel coding rates. In this system, MIMO-OFDM is used to increase the channel capacity and mitigate the inter-symbol interference, variable rate space frequency codes and Reed Solomon codes are adopted to combat the channel errors, and error resilient source coding schemes are applied to restrict the error propagation. In case network congestion may happen, packet erasure codes are used to alleviate the packet dropping. The advantages of the proposed system lie in three aspects: adaptivity, optimality, and low complexity. Based on the characteristics of the image content, the estimated channel conditions, and the distortion constraint, the proposed low-complexity joint source channel coding and rate control algorithm adjusts the coding and transmission strategies adaptively, which can approximate the optimal solution with a tight bound

Research on Underwater Color Image Compressing Coding Basing on Wavelet Transform

海洋环境具有十分重要的意义，支持对上述研究的展开和进行的重要工作之一就是解决如何将水下获取的各种信息（数据、声音、图像等）准确而高效率地进行传输。这不仅涉及到对于复杂而又窄带的水声信道需要进行有效的信道编码研究，对于大数据量的彩色图像信息高质量地进行压缩编码方法研究同样具有十分重要地现实意义。因此本论文的主要目的是为水下图像传输系统寻找一种高效的彩色图像压缩编码方法，并且在恶劣的海洋水声环境中能够具有高的容错性能，保证图像恢复的质量。为了此目的，我们研究了三种基于小波变换的图像压缩编码方案－EZW算法，SPIHT算法，SPECK算法。并对具体的样例用实验分别得到实验的结果，在分析对比实验结果的...The researches upon ocean environment are of great meaning. One important part of the researches is how to transmit multimedia information exactly and efficiently in the underwater acoustic, which includes data, voice and image transmission. It not only refers to channel coding study upon the complicated and being narrowband underwater acoustic channel, but also plays an important role in the comp...学位：理学硕士院系专业：计算机与信息工程学院电子工程系_无线电物理学号：20013000