基于ADV611的航空图像压缩系统设计

针对航空图像压缩系统的要求,基于采用提升方案的整数小波变换(IWT)和改进SPHIT算法的ADV611芯片,设计了一种航空图像压缩系统,该系统具有多比例、多分辨率的优点,能根据实际情况灵活设置压缩比例。     

静态图像无损/近无损压缩技术研究

针对航空侦察图像的原始分辨率高,且在存储过程中必须进行无损或者近无损图像压缩的问题,为满足任务判读的要求,实现实时高效的数据压缩处理具有重要的工程价值。本文首先比较了几种无损或者近无损图像压缩的硬件平台,然后介绍了JPEG标准族的无损/近无损图像压缩的算法框架和不足,最后阐述了最近刚正式问世的新一代JPEG XR图像压缩标准,并指出了JPEG XR标准的优势所在。     

数据结构优化在多小波图像压缩中的应用

提出了一种数据结构的优化方式，并将其应用到多小波图像压缩中。实验结果表明，利用所提出的优化方法对多小波系数及位置信息进行处理时不仅能够很好地恢复原始图像而且与普通域值法相比可在相同的图像文件压缩率下提高其峰值信噪比     

无人机载SAR图像压缩传输中的关键技术研究

本文在深入研究EBCOT算法的基础上.对算法进行了部分改进.设计了基于JPEG2000标准的SAR图像压缩算法,并完成了该算法的软件设计工作,并对其压缩性能和容错性能进行了分析.     

复合材料的三基圆缠绕成形方法

介绍了一种具有三维复合材料性能的三基圆缠绕成形方法。用该方法可以制成复杂的整体承力的刚架结构，还可成形各种大厚度板材。与目前的复合材料成形工艺相比，具有工艺简单，应用范围广等优点。     

基于神经网络的导弹稳定控制回路设计方法

基于径向基函数神经网络（RBFNN）的学习能力和逼近特性，将传统方法中的局部/整体构架蕴涵于神经网络内部，对导弹稳定控制律进行局部（定点）/整体（拟合）设计，以简化计算步骤，提高设计方法的通用性和自动化程度，以防空导弹侧向稳定控制回路设计为背景，对所提出的稳定控制回路设计方法进行了仿真，验证了该方法的可行性和有效性。     

改性双马来酰亚胺树脂预浸料及成形工艺

该论文讨论了改性双马来酰亚胺树脂的预浸工艺，预浸料的贮存性能以及成形工艺，该树指适合于湿法预浸，预浸料粘性适中，室温下的粘性贮存期大于１４ｄ，后固化温度低于２００℃，加压带较宽，具有较佳的工艺性能。     

民航卫星通信网可视通信图像压缩编码方法研究

对民航卫星通信网进行可视通信图像压缩编码方法进行了研究。通过在多媒体计算机上进行模拟实验表明，将视频信息及语音信息压缩为64kbps通过TES卫星网传输方案是可行的。     

基于提升方案的无损图像压缩系统的DSP实现

以 TMS320C6711DSK 为开发平台,研究了提升小波应用于无损图像压缩系统的 DSP 实现过程。为了满足系统的实时要求,对系统方案进行了合理选择,并对系统算法进行了改进,然后采用多种优化手段对程序进行了优化,实验结果证明了该方案的可行性。     

晶须和短纤维混杂增强铝基复合材料研究

简要介绍了ＳｉＣ晶须和Ａｌ２Ｏ３短纤维混杂增强铝基复合材料的制造工艺，并对材料的力学性能进行了测试，对金相组织和扫描断口进行了观察。结果表明，用该工艺制造出增强剂分布均匀的复合材料，材料的性能尤其是抗拉强度有了较大幅度的提高，复合材料中晶短纤维的增强机理明显不同，该材料有望在大功率发动机上得到应用。     

边缘图像自适应编码方法

边缘特征常被视作无人机视觉系统中的重要信息（比如在视觉导航时需用边缘特征识别障碍物），在实践中会遇到边缘图像数据量大的情况。针对边缘图像高效压缩问题，提出了边缘图像自适应编码方法。首先以边缘打包法的压缩比和边缘点所占比例为特征，建立Logistic回归模型，然后利用图像数据库对该模型进行离线训练获取模型参数，最后利用Logistic回归模型建立分类器，自适应地在边缘打包法和链码编码法中选择压缩比最高的方法对边缘图像进行压缩。对VOC2012图像数据库的测试结果表明，与常用压缩方法相比，提出的算法能提高压缩比5%左右，有效减少了数据量。     

Image Quality Evaluation in Security Imaging Systems

The subjective image quality of image or video information is a crucial item in security imaging systems. During the last five years our lab has tested and verified various approaches to the image compression for security purposes and the evaluation of subjective image quality. In the paper we discuss selected important facts related to the subjective image quality evaluation and we present some anomalous experimental behavior of image compression techniques. An object-defined approach is investigated and advantageous characteristics of chosen methods are deployed to achieve the optimal performance of the surveillance video coder. Among others, we propose to use the artificial neural network (ANN) to predict resulting image quality rating scores. The proposed quality assessment model has been trained and tested using a set of grayscale images distorted by selected image compression algorithms     

Synthetic aperture radar image formation from compressed data usinga new computation technique

A convolution technique is proposed that allows direct reconstruction of the processed synthetic-aperture radar (SAR) image from the digitally-sampled, block-encoded raw data. This computational compression technique reduces the number of arithmetic operations from that required by fast Fourier transform (FFT) convolution for SAR processing. SAR phase histories are block encoded and directly processed into an image where only arithmetic additions are required for the processing. For SAR data previously block encoded, the processing time is reduced by a factor of 100 or more. A speed-up of three times over SAR processing by FET convolution has been demonstrated when both computation of the block encoding and subsequent direct processing are included in the time. SAR image quality measurements for a method of block encoding called vector quantization at compression ration ranging from 5:1 to 50:1 show image degradation proportional to the compression ratio. For a 5:1 compression radio, image quality measurements show minimal degradation     

On-Board Image Compression for the RAE Lunar Mission

The requirements, design, implementation, and flight performance of an on-board image compression system for the lunar orbiting Radio Astronomy Explorer-2 (RAE-2) spacecraft are described. The image to be compressed is a panoramic camera view of the long radio astronomy antenna booms used for gravity-gradient stabilization of the spacecraft. A compression ratio of 32 to 1 is obtained by a combination of scan line skipping and adaptive run-length coding. The compressed imagery data are convolutionally encoded for error protection. This image compression system occupies about 1000 cm2 and consumes 0.4 W.     

Compression standards and alternative methods for video telecom

The complex video compression methods in the process of being standardized, which are designed to reduce transmission needs by detecting and coding image redundancy temporally and spatially between frames, are examined. Methods involving fractals, and wavelets may achieve more efficient coding by defining spatial formats and equations more applicable to the specific image than the more general-purpose transforms of the standards. A newer method involves the capture of an entire database of image characteristics and identifies and stores the 3-D motion in the image field. The image can be reproduced at high compression rates at remote locations. Telecommunication products that facilitate the operation and use of video compression systems are presented     

Collaborative image compression and classification with multi-task learning for visual Internet of Things

Widespread deployment of the Internet of Things(Io T) has changed the way that network services are developed, deployed, and operated. Most onboard advanced Io T devices are equipped with visual sensors that form the so-called visual Io T. Typically, the sender would compress images, and then through the communication network, the receiver would decode images, and then analyze the images for applications. However, image compression and semantic inference are generally conducted separately, and t...     

JPEG2000的核心算法研究

随着网络和多媒体技术的发展,对静态图像压缩不仅要求有较高的压缩性能,而且还要求有新的功能来适应一些特殊的要求。JPEG2000是一种新的图像编码标准,它具有优良的压缩性能和很高的灵活性,而且系统功能比以前所有的图像压缩标准都先进。通过对JPEG2000中核心算法的分析,阐述了JPEG2000压缩过程以及与现有压缩标准相比显示出来的优越性能。     

飞机信息传输系统研究

首先描述飞机信息传输系统(AITS)应具有的功能;然后叙述构成AITS的机载信息分系统、信息传输分系统和地面管理分系统;最后,给出了基于小波变换编码的图像压缩/解压的图像处理。