The technique of quasi-lossless compression of the remote sensing image

In this paper, the technique of quasi-lossless compression based on the image restoration is presented. The technique of compression described in the paper includes three steps, namely bit compression, correlation removing and image restoration based on the theory of modulation transfer function (MTF). The quasi-lossless compression comes to a high speed. The quality of the reconstruction image under restoration is up to par of the quasi-lossless with higher compression ratio. The experiments of the TM and SPOT images show that the technique is reasonable and applicable.     

遥感图像准无损压缩技术的研究

提出了一种基于图像恢复技术的遥感图像压缩技术,在提高遥感图像压缩比的同时,使压缩后的重建图像质量达到准无损的技术要求。对SRTF、TM图像的试验结果表明,该技术是可行的。     

基于Mask原理的遥感影像恢复技术研究

从传统摄影复制技术中的Mask晒像原理出发 ,针对航空航天遥感影像上出现四周减光、照度与颜色不均匀、对比度下降、影像模糊等质量退化情况 ,提出将影响影像退化的各种因素综合考虑 ,通过一种基于Mask的影像复制技术来建立影像降质模型 ,并以此Mask影像对遥感影像进行恢复处理。试验结果表明 ,该恢复算法是可行的。     

基于景物灰度分布特征的影像恢复技术

从刀刃曲线求取ＭＴＦ的基本理论入手,介绍了从数字影像中提取刀刃曲线的方法,简要说明了图像在频率域和空间域中的恢复过程。实验证明,ＭＴＦ理论在影像恢复中有很大的应用潜力。     

城市三维可视化中规则房屋墙面纹理图像的压缩与恢复

以城市三维可视化中的房屋墙面纹理图像为对象，就其压缩与恢复的方法进行了研究，提出了一种基于自相似性墙面纹理分割的纹理图像压缩与恢复方法，以及对由于遮挡而墙面不完整的纹理图像的复原方法，并通过实例说明了此种方法对于城市三维可视墙面纹理贴图的实用性。     

Effects of jpeg 2000 compression on automated dsm extraction: evidence from aerial photographs

This paper evaluates the effects of JPEG 2000 compression on automated digital surface model (DSM) extraction, using the area-based matching technique. Two stereopairs of aerial photographs, which have different photo scale, pixel size, and topographic type, are used as the images for the experiments. In the experiments, the DSM generated from the uncompressed image is set as the reference, and the elevation accuracy is computed for a range of compression ratios (2:1 to 100:1). The results show that the employed indices of image quality based on the JPEG 2000 compression are clearly superior to the commonly used JPEG compression technique—especially for high compression ratios. However, the elevation accuracy varies with the compression ratios. Also, JPEG 2000 compression does not have a significant influence on the percentage of the successful matching rate. In addition, a near linear fall-off is observed in extracted DSM accuracy with increasing compression ratios.     

Correlation-based band-ordering heuristic for lossless compression of hyperspectral sounder data

A novel algorithm for the lossless compression of hyperspectral sounding data is presented. The algorithm rests upon an efficient technique for three-dimensional image band reordering. The technique is based on a correlation factor. The correlation-based band ordering gives 5% higher compression ratios than natural ordering does. On the other hand, the obtained compression ratios are within a percent of those produced by optimal ordering, but the computational time is much lower compared to the optimal ordering. The low computational complexity of the algorithm is based on the use of correlation for the band ordering. Moreover, the algorithm results in 7% to 12% improvement over fast nearest neighbor reordering scheme versions of JPEG-LS and the context-based adaptive lossless image codec algorithms.     

Fractal compression of satellite images

Fractal geometry provides a means for describing and analysing the complexity of various features present in digital images. In this paper, characteristics of Fractal based compression of satellite data have been tested for Indian Remote Sensing (IRS) images (of different bands and resolution). The fidelity and efficiency of the algorithm and its relationship with spatial complexity of images is also evaluated. Results obtained from fractal compression have been compared with popularly used compression methods such as JPEG 2000, WinRar. The effect of bands and pixel resolution on the compression rate has also been examined. The results from this study show that the fractal based compression method provides higher compression rate while maintaining the information content of RS images to a great extent than that of JPEG. This paper also asserts that information loss due to fractal compression is minimal. It may be concluded that fractal technique has many potential advantages for compression of satellite images.     

影像压缩为数字摄影测量产品应用带来的扩展

主要讨论利用影像压缩技术为建立正射影像管理系统服务,并对其能达到的效率进行分析,从而说明影像压缩能为测绘产品的应用领域带来一些扩展。并简要讨论了利用影像压缩技术在其他方面的应用。     

基于卡尔曼运动模型模糊图像恢复技术研究

提出了一种基于卡尔曼运动模型进行运动模糊图像退化过程分析的方法 ,设计了基于卡尔曼运动质量退化模型的运动模糊图像恢复算法 ,该方法逼近实际的运动模型。通过对火车称重系统中的模糊影像恢复实验 ,表明了该恢复技术的有效性     

基于分形方法的图像压缩在WebGIS上的应用

万维网地理信息系统（WebGIS）是地理信息系统（GIS）发展的必然趋势，但在图像传输和保存方面还有很多尚等解决的问题。分形方法在图像压缩方面有很强优势，利用分形方法对地图图像进行压缩以减少数据量，在WebGIS上具有非常广阔的应用前景。     

基于调和模型的连续Hopfield神经网络次优图像复原

本文提出了一种基于调和模型的连续Hopfield神经网络正则化次优图像复原算法。针对传统正则化图像复原由于"模糊矩阵"和"高通滤波器"规模庞大而带来的复原过程中占用存储资源多的问题,提出了一种基于部分图像信息的次优复原算法,该算法能在性能下降不大的前提下,较好地解决传统复原资源消耗问题。同时算法采用由梯度算子生成的调和模型作为正则项,能在复原的同时保留图像边缘。仿真结果表明了算法的有效性。     

城区大比例尺影像三维景观重建

本文利用目标提取技术,根据近似点位进行房屋角点的自动定位,自动搜索同名点,然后建立一个尽可能多地包含房顶面的目标窗口,取代传统的以房角为中心的窗口进行房顶角点影像匹配,提高了房顶角点匹配的可靠性,实现了航空影像房屋三维数据的半自动量测。进而在地面与建筑物表面二维半不规则三角网和原始数字影像的基础上,实现了建筑物可见表面纹理的恢复,重建了城市真实三维景观。     

基于小波变换的多光谱图像压缩方法

在分析多光谱图像小波变换后系数特点的基础上,提出了一种共享有效图的小波变换压缩方法（ＳＳＭＷＴ）。该方法将小波变换压缩技术中的零树编码推广到多光谱图像压缩中,利用多光谱图像的结构相关性,对多幅小波图像只需构造一幅有效图,同时去除空间冗余和谱间结构冗余,并与Ｋ－Ｌ变换相结合,进一步去除谱间统计冗余,实验表明了该方法的有效性。     

小波变换在遥感图像压缩中的应用

基于遥感数据的大信息量、大容量和越来越高的分辨率对图像的存储和传输提出的更高要求,有效的图像压缩就显的特别重要。在综合比较了各种压缩编码算法的基础上,结合遥感图像本身的特点和对小波变换性质的深入分析,选择了基于小波变换的遥图像压缩方法。     

一种基于退化模型的高分辨率SAR去噪算法

为了保持高分辨率合成孔径雷达（SAR）图像中的纹理结构，提出了一种基于高斯．马尔可夫模型（Gauss-Markov Model）的方法来抑制SAR图像的斑点噪声。通过引入贝叶斯分析框架，建立Markov随机场的退化图像恢复模型，从而将图像的恢复问题转化为求解最大后验概率（MAP）问题，并直接从噪声图像中估计随机场模型参数进行有效的噪声抑制。实验结果表明，对所研究的高分辨SAR图像，基于退化模型的去噪算法（RMBD）不论是在噪声的去除上还是在结构信息等细节的保持上均不同程度地优于其他常用斑点去噪方法。     

基于图像结构的无参考模糊图像及其复原图像质量评价方法

针对传统图像的质量评价测度。提出了一种基于边缘检测的无参考模糊图像评价模型。通过测量梯度图像的梯度边缘信息,来评价模糊退化图像和带有模糊效应的复原图像,实验表明：利用本测度所得到的模糊图像质量评价结果与主观评价结果有很好的相关性。本测度较准确地反映了人,对模糊图像质量的主观感受,对于带有模糊效应的复原图像的评价结果也较为符合主观评价结果。     

Satellite/Aerial Image Compression Using Adaptive Block Truncation Coding Technique

Satellite/aerial images taken from high altitude contain large amount of pixels to store accurate information. These high resolution images require large storage capacity and more transmission time. Applying an efficient compression technique on these images can reduce high storage capacity requirement and transmission time. In this paper block truncation coding (BTC) based color image compression technique for aerial/satellite images is proposed. High degree of correlation among the RGB planes of a color image can be reduced by converting these planes into HSV planes. Each of the H and S planes are encoded using BTC with quad clustering and V plane is encoded with BTC based bi-clustering or tri-clustering depending on the edge information present in the plane. The effectivity of the proposed method is validated by comparing it with the conventional BTC and its variant methods. Experimental analysis indicate that the proposed method is superior to other state of the art methods both in terms of visual quality and quantitative metrics.     

基于立体补偿的遥感立体像对压缩方法

提出研究遥感立体像对的压缩问题。主要讨论了左右影像的视差补偿和辐射补偿。针对遥感立体像对视差分布不均以及左右影像存在辐射差的特点,提出了一种基于立体补偿的遥感立体像对压缩算法。该算法以左片为基准图像,采用自适应视差估计计算出右片的视差矢量,结合辐射校正和重叠块视差补偿技术得到平滑的右片的预测图像,以右片减去预测图像得到残差图像,然后采用小波压缩算法对残差图像进行压缩。实验结果表明,该算法能显著提高遥感立体像对的压缩性能。     

遥感影像的形状参数

基于小波变换的图像压缩编码方法需要知道小波变换后各子带图像的概率密度函数的形状参数，以便设计出最佳的量化器。在本文中，通过ＫＳ（Ｋｏｌｍｏｇｏｒｏｖ—Ｓｍｉｒｎｏｖ）检验的方法给出了遥感影像小波变换后各子带图像的形状参数，为遥感影像利用小波变换进行压缩提供了设计量化器的依据。