Research Dynamics of the Classification Methods of Remote Sensing Images

As the key technology of extracting remote sensing information,the classification of remote sensing images has always been the research focus in the field of remote sensing. The paper introduces the classification process and system of remote sensing images. According to the recent research status of domestic and international remote sensing classification methods,the new study dynamics of remote sensing classification,such as artificial neural networks,support vector machine,active learning and ensemble multi-classifiers,were introduced,providing references for the automatic and intelligent development of remote sensing images classification.

Rapid identification of landslide,collapse and crack based on low-altitude remote sensing image of UAV

Landslides,collapses and cracks are the main types of geological hazards,which threaten the safety of human life and property at all times.In emergency surveying and mapping,it is timeconsuming and laborious to use the method of field artificial investigation and recognition and using satellite image to identify ground hazards,there are some problems,such as time lag,low resolution,and difficult to select the map on demand.In this paper,a10 cm per pixel resolution photogrammetry of a geological hazard-prone area of Taohuagou,Shanxi Province,China is carried out by DJ 4 UAV.The digital orthophoto model(DOM),digital surface model(DSM) and three-dimensional point cloud model(3 DPCM) are generated in this region.The method of visual interpretation of cracks based on DOM(as main)-3 DPCM(as auxiliary) and landslide and collapse based on 3 DPCM(as main)-DOM and DSM(as auxiliary) are proposed.Based on the low altitude remote sensing image of UAV,the shape characteristics,geological characteristics and distribution of the identified hazards are analyzed.The results show that using UAV low altitude remote sensing image,the method of combination of main and auxiliary data can quickly and accurately identify landslide,collapse and crack,the accuracy of crack identification is 93%,and the accuracy of landslide and collapse identification is 100%.It mainly occurs in silty clay and mudstone geology and is greatly affected by slope foot excavation.This study can play a great role in the recognition of sudden hazards by low altitude remote sensing images of UAV.

Edge detection method for remote sensing image based on morphological variable structuring element

There are problems such as incomplete edges and poor noise suppression when a single fixed morphological structuring element is used to detect the edges in remote sensing images. For this reason, a morphological edge detection method for remote sensing image based on variable structuring element is proposed. Firstly, the structuring elements with different scales and multiple directions are constructed according to the diversity of remote sensing imagery targets. In order to suppress the noise of the target background and highlight the edge of the image target in the remote sensing image by adaptive Top hat and Bottom hat transform, the corresponding adaptive morphological operations are constructed based on variable structuring elements; Secondly, adaptive morphological edge detection is used to obtain multiple images with different scales and directional edge features; Finally, the image edges are obtained by weighted summation of each direction edge, and then the least square is used to fit the edges for accurate location of the edge contour of the target. The experimental results show that the proposed method not only can detect the complete edge of remote sensing image, but also has high edge detection accuracy and superior anti-noise performance. Compared with classical edge detection and the morphological edge detection with a fixed single structuring element, the proposed method performs better in edge detection effect, and the accuracy of detection can reach 95 %

Influences of Atmospheric Turbulence on Image Resolution of Airborne and Space-Borne Optical Remote Sensing System

A new way is proposed to evaluate the influence of atmospheric turbulence on image resolution of airborne and space-borne optical remote sensing system, which is called as arrival angle-method. Applying this method, some engineering examples are selected to analyze the turbulence influences on image resolution based on three different atmospheric turbulence models quantificationally, for the airborne remote sensing system, the resolution errors caused by the atmospheric turbulence are less than 1 cm, and for the space-borne remote sensing system, the errors are around 1 cm. The results are similar to that obtained by the previous Friedmethod. Compared with the Fried-method, the arrival angle-method is rather simple and can be easily used in engineering fields.

A classification method of building structures based on multi-feature fusion of UAV remote sensing images

In order to improve the accuracy of building structure identification using remote sensing images,a building structure classification method based on multi-feature fusion of UAV remote sensing image is proposed in this paper.Three identification approaches of remote sensing images are integrated in this method:object-oriented,texture feature,and digital elevation based on DSM and DEM.So RGB threshold classification method is used to classify the identification results.The accuracy of building structure classification based on each feature and the multi-feature fusion are compared and analyzed.The results show that the building structure classification method is feasible and can accurately identify the structures in large-area remote sensing images.

Semi-supervised kernel FCM algorithm for remote sensing image classification

These problems of nonlinearity, fuzziness and few labeled data were rarely considered in traditional remote sensing image classification. A semi-supervised kernel fuzzy C-means （SSKFCM） algorithm is proposed to overcome these disadvantages of remote sensing image classification in this paper. The SSKFCM algorithm is achieved by introducing a kernel method and semi-supervised learning technique into the standard fuzzy C-means （FCM） algorithm. A set of Beijing-1 micro-satellite＇s multispectral images are adopted to be classified by several algorithms, such as FCM, kernel FCM （KFCM）, semi-supervised FCM （SSFCM） and SSKFCM. The classification results are estimated by corresponding indexes. The results indicate that the SSKFCM algorithm significantly improves the classification accuracy of remote sensing images compared with the others.

Improving wavelet reconstruction algorithm to achieve comprehensive application of thermal infrared remote sensing data from TM and MODIS

According to the data characteristics of Landsat thematic mapper （TM） and MODIS, a new fu sion algorithm about thermal infrared data has been proposed in the article based on improving wave let reconstruction. Under the domain of neighborhood wavelet reconstruction, data of TM and MO DIS are divided into three layers using wavelet decomposition. The texture information of TM data is retained by fusing highfrequency information. The neighborhood correction coefficient method （NC CM） is set up based on the search neighborhood of a certain size to fuse lowfrequency information. Thermal infrared value of MODIS data is reduced to the space value of TM data by applying NCCM. The data with high spectrum, high spatial and high temporal resolution, are obtained through the al gorithm in the paper. Verification results show that the texture information of TM data and high spec tral information of MODIS data could be preserved well by the fusion algorithm. This article could provide technical support for high precision and fast extraction of the surface environment parame ters.

Adaptive regularized scheme for remote sensing image fusion

We propose an adaptive regularized algorithm for remote sensing image fusion based on variational methods. In the algorithm, we integrate the inputs using a ＂grey world＂ assumption to achieve visual uniformity. We propose a fusion operator that can automatically select the total variation （TV）-LI term for edges and L2-terms for non-edges. To implement our algorithm, we use the steepest descent method to solve the corresponding Euler-Lagrange equation. Experimental results show that the proposed algorithm achieves remarkable results.

Visual remote sensing image fusion using local correlation moment

In this paper a fusion method is proposed for merging a high-resolution panchromatic image and a lowresolution multispectral image. The algorithm is based on discrete wavelet transform (DWT). It uses correlation moment rule to the low frequency bands and local deviation rule to the high frequency bands separately. Experimental results indicate that the proposed approach outperforms the traditional methods.

PCA-based sea-ice image fusion of optical data by HIS transform and SAR data by wavelet transform

Sea ice as a disaster has recently attracted a great deal of attention in China. Its monitoring has become a routine task for the maritime sector. Remote sensing, which depends mainly on SAR and optical sensors, has become the primary means for sea-ice research. Optical images contain abundant sea-ice multi-spectral in-formation, whereas SAR images contain rich sea-ice texture information. If the characteristic advantages of SAR and optical images could be combined for sea-ice study, the ability of sea-ice monitoring would be im-proved. In this study, in accordance with the characteristics of sea-ice SAR and optical images, the transfor-mation and fusion methods for these images were chosen. Also, a fusion method of optical and SAR images was proposed in order to improve sea-ice identification. Texture information can play an important role in sea-ice classification. Haar wavelet transformation was found to be suitable for the sea-ice SAR images, and the texture information of the sea-ice SAR image from Advanced Synthetic Aperture Radar （ASAR） loaded on ENVISAT was documented. The results of our studies showed that, the optical images in the hue-intensi-ty-saturation （HIS） space could reflect the spectral characteristics of the sea-ice types more efficiently than in the red-green-blue （RGB） space, and the optical image from the China-Brazil Earth Resources Satellite （CBERS-02B） was transferred from the RGB space to the HIS space. The principal component analysis （PCA） method could potentially contain the maximum information of the sea-ice images by fusing the HIS and texture images. The fusion image was obtained by a PCA method, which included the advantages of both the sea-ice SAR image and the optical image. To validate the fusion method, three methods were used to evaluate the fused image, i.e., objective, subjective, and comprehensive evaluations. It was concluded that the fusion method proposed could improve the ability of image interpretation and sea-ice identification.

基于NSST与稀疏先验的遥感图像去模糊方法

针对遥感图像的模糊问题,设计一种基于非下采样剪切波变换与稀疏先验的图像复原算法.首先,利用遥感图像在非下采样剪切波分解下的高频图像的稀疏特性设置先验条件构造图像复原模型;其次,采用交替方向乘子法求解模型;再次,采用软阈值方法对高频图像进行约束处理,在低频图像进行导向滤波处理,以最大可能保留图像的细节信息;最后,将高频图像与低频图像进行重构,对重构后的图像采用卷积神经网络进行深度去噪,最终复原出清晰的图像.将该去模糊算法与H-PNP,GSR,L2TV算法进行实验对比.实验结果表明,该算法能有效去除遥感图像中的模糊和噪声,保留图像的边缘细节,客观评价指标均高于其他3种对比实验算法.

遥感图像变化检测方法研究综述

遥感图像变化检测是遥感领域中一项重要的研究内容,其旨在利用遥感技术和图像处理方法来识别地表覆盖变化的模式和趋势。为了深入了解该方面的发展现状及其使用的技术方法,总结分析了大量的资料和文献,对遥感图像变化检测方法进行了较为全面的综述。介绍了变化检测的概念和处理流程;从6个角度总结了变化检测方法的分类体系,并回顾了其发展历程;概述了各类变化检测方法的原理和特点,对其优缺点进行了简要分析,从6个方面讨论了对遥感图像进行变化检测的现实应用价值;对存在的一些问题与不足进行了简要分析,提出了可能改善这些问题的方法,同时也预言了这些方法在实际应用中可能会遇到的阻碍。最后,对变化检测方法进行总结,并展望了未来的发展方向,以期更好地了解遥感图像变化检测方法的研究现状和发展趋势,为进一步的研究提供参考。

基于多季相分形特征的Landsat 8 OLI影像耕地信息提取方法

利用遥感技术快速准确地提取耕地信息是耕地保护的关键环节。以山东省商河县为例,提出了一种基于多季相分形特征的Landsat 8 OLI影像耕地信息提取方法。首先采用毯子覆盖法计算多季相遥感影像每个像元的上分形信号和下分形信号,对比分析耕地和其他土地利用类型的分形特征,选取上分形信号的第3尺度作为特征尺度,提取商河县耕地空间分布特征;其次采用同时期的土地利用矢量数据、Esri land cover数据和统计数据进行耕地信息提取精度评价;最后分别设置多季相分形提取与单季相分形提取、现有土地利用数据产品的对比实验,并基于点位匹配度和面积匹配度进行评价。结果表明:多季相数据更能反映农作物生长的复杂性,有助于提高耕地信息的提取精度;不同土地利用类型在不同分形尺度的信号值各不相同,分形特征可以在不同尺度上清晰地刻画出不同土地利用类型的分异性;基于矢量数据和Esri land cover数据评价的多季相分形特征耕地提取点位匹配度为87.13%和89.83%,面积匹配度为99.73%和97.91%,均比单季相分形提取结果精度高;综合考虑点位匹配度、面积匹配度和空间分布特征,研发方法能有效区分耕地和其他土地利用类型,提取结果更优,且与统计数据有更高的一致性。该方法可准确提取耕地信息,为耕地的动态监测和损害评估提供技术支撑。

高分辨率遥感图像的目标检测

卫星遥感图像的分辨率高且目标在图像内的相对尺寸小,因此难以同时确保检测准确率和运行速度。为解决高像素遥感图像的目标检测问题,本文提出了一种结合滑动窗口分割和小目标检测器的检测方法。首先使用滑动窗口法将图像分割成多个子图,滑动步长略小于窗口的大小以使每个子图之间具有一定的重叠部分,并采用较大的分割窗口以降低子图数量。之后对子图进行压缩,使用目标检测算法处理压缩后的图片,降低算法运行时间。最后合并检测结果并采用非极大化抑制策略以去除在重叠部分重复检测的目标。在检测算法方面,本文以YOLOv8n为基础,使用SPD卷积核对网络结构进行改进,基于NWD方法调整正负样本匹配策略,并改进特征金字塔结构以提升算法对小目标的检测性能,从而使算法能够适应在更大尺寸下压缩的子图以减少图像分割数量,提升检测速度。实验证明,在图像平均分辨率为4000×4000的车辆检测数据集上,该方法对目标检测的平均准确率为55.7%,平均每张图片的计算时间约为47.5 ms,准确率比YOLOv8n提升16%,比YOLOv5s提升15%,比YOLOv6s提升7.6%。本文方法的运行效率满足实时化要求,能够以更高精度实时检测卫星遥感图像中的目标。

基于机器学习方法的高光谱遥感图像目标检测研究

针对高光谱遥感图像目标检测的难题,提出基于机器学习的高光谱遥感图像目标检测方法。首先,通过动力演化算法找到满足偏度、峰度最大化的投影方向,将高维图像数据投影至低维子空间,从而提取图像的光谱信息。然后,通过线性判别法将提取的信息转换为直方图形式,再利用自动标记分水岭算法和KNN方法进行目标区域的初分割和分类,以去除非目标光谱像元。测试结果表明,对目标信息进行检测处理后,图像像元整体分类精度与平均分类精度数值区间为[0.97,0.98],信息熵数值仅有0.01,说明该方法具有较高精度,结果可信度较高。

基于无人机倾斜摄影遥感技术的水土保持动态监测方法研究

为了能够充分了解土壤侵蚀分布,及时掌握水土流失变化趋势,提出基于无人机倾斜摄影遥感技术的水土保持动态监测方法。利用无人机从多个角度采集监测区域影像数据,并实施辐射定标和大气校正预处理,基于遥感影像数据提取土壤可蚀性因子、土地利用因子、植被覆盖监测因子、坡度因子,通过计算获取水土保持系数并划分等级。监测结果表明:区域1水土保持系数呈现“V字形”,区域2水土保持系数整体呈现“一字型”,区域3水土保持系数整体呈现逐渐上升状态。

遥感数据分析的矿山边坡变形监测方法

为实现对矿山边坡的实时监测,通过结合无人机数字低空遥感测量技术,建立矿山三维坐标体系并设定测站点中心,对矿山边坡累计变形量与变形速率进行实时监测。实验结果表明:设计的监测方法具有良好应用效果,使矿山边坡变形监测结果的误差得到较好控制,实现对其异常状态与变形的及时感知与快速处理。

基于内容解译的遥感图像推荐方法

随着遥感技术的不断发展,遥感数据呈现出海量增多的趋势,如何提供精准及时的遥感信息推荐服务成为亟待解决的问题。现有的遥感图像推荐算法大多针对用户画像进行设计,忽视了图像内容的语义信息对推荐结果的影响。针对上述问题,提出一种基于内容解译的遥感图像推荐方法。首先,通过基于YOLOv3的目标检测模块对遥感图像进行目标提取;然后,整合关键目标的位置分布向量作为图像内容信息;同时,构建多元素的用户兴趣画像,并根据用户主动搜索历史进行动态调整,以提高推荐结果的个性化程度;最后,将图像内容信息与图像自带属性信息、用户画像模型进行匹配,实现遥感数据的精准智能推荐。在真实订单数据上与较新的仅基于图像属性信息的推荐方法进行对比实验,实验结果表明,所提方法在实验数据上取得的正负样本区分度比考虑用户画像的推荐方法提高了70%;在耗时基本相近的情况下,在使用10%训练数据时,推荐错误率与对比方法相比下降了4.0~5.6个百分点,而在使用100%训练数据时推荐错误率则下降了0.6~1.0个百分点,验证了所提方法的可行性与有效性。

多分支特征映射的遥感图像目标检测算法

由于遥感图像具有背景复杂、目标较小且密集、尺度连续变化大等特点,通用目标检测器难以较好地适应,导致检测效果不佳。针对以上问题,基于YOLOv5s模型,提出一种多分支特征映射的遥感图像目标检测算法。首先,利用结构重参数化技术设计一种结合门控通道转换的RepVGG模块,采用其串联结构替换原主干网络的C3模块,聚合全局上下文信息,增强特征表达和特征提取能力;其次,使用自适应指数加权池化方法以及逆过程重构特征融合网络的采样方式,最大化地保留特征信息,改善较小目标的检测效果;最后,引入EIoU和Focal Loss组合作为模型的损失函数,优化预测框的回归速率以及难易样本的损失权重分配,进一步提高定位精度。在DIOR和NWPU VHR-10数据集上的实验结果表明,提出算法的平均精度均值分别达到92.2%、92.5%,较YOLOv5s分别提高了3.5个百分点、5.6个百分点,达到了更好的检测效果,同时实时性也满足实际场景下的遥感图像目标检测。

无人机航测遥感图像边缘畸变自适应校正方法研究

为提升遥感图像边缘畸变处理清晰度,提出无人机航测遥感图像边缘畸变自适应校正方法研究。根据当前校正需求,先进行图像边缘畸变特征的提取,采用多阶的方式,提升校正的整体效率,并设定多阶自适应校正机制。基于此,构建遥感图像边缘畸变自适应校正模型,采用线性放射辅助变换的方式来实现校正处理。测试结果表明:处理后图像边缘清晰度在第三阶段均可以达到300 ppi以上,具有稳定、灵活、高效的特点。