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针对目前使用机器学习解决高分辨率遥感图像分类主要存在下采样导致的细节信息丢失问题,提出了一种基于DeepLabv3架构的小波域DeepLabv3-MRF(Markov random field,MRF)算法。选择当前较为普遍的DeepLabv3架构分类算法,能够获得更为精确的分类结果;采用小波域DeepLabv3-MRF算法,还能够获得更为清晰的边缘细节信息。选取南方某地区高分辨率无人机遥感图像进行分类实验,通过小波变换的方向性、非冗余性以及MRF变换像素空间的交互性这三个方面,将分类结果与原始DeepLabv3架构分类结果对比分析。结果表明,所提出的分类方法精度明显高于原始DeepLabv3架构分类算法的精度,总体精度可提升3%左右,并且可以充分表达高分辨率遥感图像细节信息。 相似文献
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通过研究、分析现有基于遥感影像的舰船检测算法,提出了基于Itti视觉显著度模型改进的高分辨率遥感影像海面舰船检测方法,该方法利用海面舰船相对于海面背景信息视觉关注高的特点,参考视觉显著度模型计算原理,对高分辨率遥感影像中的颜色、亮度、方向、纹理等特征进行有效提取,然后利用归一化方法将不同特征融合,形成有利于舰船目标提取得视觉显著度图,最后对生成的视觉显著度图进行阈值分割和精细化处理获得最终的舰船检测结果。与传统舰船检测算法相比,本文算法能够有效检测复杂海面背景下的舰船目标,减少了单一特征变化对检测精度的影响,提高了检测准确率,具有较好的抗噪性和较强的鲁棒性。 相似文献
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利用高空间分辨率卫星影像准确监测浒苔绿潮对灾害早期发现、动态跟踪以及沿岸防御具有重要应用价值。目前面向高分辨率遥感影像已有多种浒苔提取方法,但不同遥感算法受到海水背景(浑浊和清澈海水)和外界观测环境(如云层、太阳耀斑、观测几何条件)等干扰,其监测效果可能受到不同程度影响。为此,以国产高分辨率GF-WFV和HJ-CCD影像为例,充分对比了归一化差值植被指数(normalized difference vegetation index,NDVI)、漂浮藻类高度虚拟基线指数(virtual baseline floating macroalgae height,VB-FAH)和绿度指数(tasseled cap greenness,TCG)在常见多种环境背景下提取浒苔的优势和不足。研究结果表明:在清澈海水、浑浊海水和弱太阳耀斑背景下,NDVI、VB-FAH和TCG三种算法均有较好的浒苔识别能力,其精度评价指标F1-score和总体分类精度(overall accuracy, OA)分别超过95.6%和95.2%。对于几何观测条件,VB-FAH和TCG算法对观测几何角度的变化不敏感并表现较高的稳定性,要优于NDVI方法。在云层覆盖和强太阳耀斑背景下,TCG算法的浒苔判识能力最好,并可有效排除云覆盖和强太阳耀斑的干扰,其精度评价指标F1-score和OA分别超过95.2%和95.0%。 相似文献
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本文基于海浪波折射现象和浅水波理论,提出了一种基于单景高分辨率光学遥感影像的浅海地形提取方法。首先,基于浅水波理论推导出适用于浅海区域的水深与海浪波长、频率的定量关系,针对近岸光学遥感图像复杂的海浪特征,讨论了两种海浪波长提取方法,即FFT方法和剖面线法。然后提出了基于长距离波长波动分析的海浪频率计算方法,解决了单景遥感影像的波浪频率计算难题。最后,利用单景QuickBird高分辨率光学遥感影像,以海南岛三亚湾为研究区域进行了应用实验,结果表明,对12m以浅的浅海区域,在不需要任何辅助参数的情况下,反演获得了浅海地形(DEM),经与1:25000比例尺海图的水深对比验证,地形趋势吻合良好,反演水深的均方根误差为1.07m,相对水深误差为16.2%,表明该方法适合于浅海水下地形的提取,且具有无需实测水深数据和环境参数的支持的优点。 相似文献
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水陆分离、云检测及算法适应性修订等前期处理过程对于提高高分辨率海表温度(sea surface temperature, SST)遥感反演精度至关重要,为解决这部分内容长期被忽视且缺乏系统性总结等问题,首先梳理了热红外图像预处理的一般流程,重点介绍了开展水陆分离和云检测的时机、原理、方法以及应着重关注的对象等;其次给出了主流SST反演算法应用在新传感器上时须进行修订的参数及方法等,并对下步各算法改进重点方向提出建议。本研究可为高分辨率SST业务化反演提供参考。 相似文献
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对东沙岛基于融合信息高分辨遥感影像分类研究 总被引:2,自引:0,他引:2
以SPOT510m多光谱高分辨率影像为数据基础,建立东沙岛地物信息提取的时空属性和地学规律等先验知识,在此基础上选取地物样本,并进行东沙岛地物光谱分析,从而进行东沙岛的融合信息分析,减少信息提取的误差,使解译的精度提高,结果表明,以先验知识为基础选取的样本光谱能够较好地反映地物光谱的信息含量;高分辨率影像能反映东沙岛的地物特征,并且在影像上能够反应东沙岛潟湖、口门等的发育状态,有效地揭示了地物的区分和地貌发育特征.以此进行的分类结果具有合理性;Kappa分析的分类精度达78.33%. 相似文献
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The approach presented is directed toward a specific adaptation of the least‐squares collocation with noise, yielding smooth predictions of geophysical quantities. The smoothing corresponds here to a truncated gravity field equivalent to an (n’, n') spherical‐harmonic expansion. This is reflected in the truncation, at the degree n‘, of the pertinent covariance and cross‐covariance functions in most (but not all) instances. The smooth predictions of geophysical quantities, made in an equilateral grid corresponding to the truncation degree n‘, serve in constructing contour maps after having been densified for the needs of a contour routine. Such a densification is carried out efficiently via errorless collocation with the degree truncation n‘ throughout. Consistent with this procedure, “residuals” at observation points (i.e., discrepancies between the contour map and the data) are computed using the same algorithm. The complete collocation approach is utilized for a 2° resolution of the earth's gravity field with emphasis on the oceanic geoid, based on the residuals from a global spherical‐harmonic adjustment of SEASAT altimetry. The presented results include contour maps of geoid undulations and gravity anomalies. They are compared to the results of a point‐mass adjustment, another technique based on the spherical‐harmonic adjustment. The agreement between these two techniques is found to be excellent. 相似文献
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The constant and harmonic parts of the global ocean tide are modeled by up to nine major tidal constituents, namely, S2, M2,
N2, K1, P1, O1, Mf, Mm, and Ssa. Our computations start with the Fourier sine and cosine series expansion for the tidal constituents,
including the constant Mean Sea Level (MSL). Although the frequencies of the tidal constituents are considered known, the
coefficients of the sine and cosine functions are assumed to be unknown. Subsequently, the coefficients of the sine and cosine
functions, as well as the constant part of the Fourier expansion, were expanded into spherical harmonics up to degree and
order n, where n corresponds to the number of linearly independent spherical harmonic base functions needed to model the tidal constituents,
determined via independent columns of the Gram matrix. The unknown coefficients of the spherical harmonic expansions are computed
using sea level observations within cycles #1–#350 of the TOPEX/Poseidon satellite altimetry over 11 years of its mission.
A set of orthonormal base functions was generated for the marine areas covered by TOPEX/Poseidon observations from the spherical
harmonics using a Gram-Schmidt orthogonalization process. These were used for modeling the dominant tidal constituents. The
computed models based on orthonormal base functions for the nine tidal constituents and the constant part of the Fourier expansion,
were tested numerically for their validity and accuracy, proving centimeter accuracy. 相似文献
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采用2005年采集的SPORT5卫星遥感影像和2015年采集的GF-1卫星遥感影像,分别对2006-2014年之间营口月亮湾海岸空间整治项目实施前后的海岸景观格局进行监测,在此基础上构建了沙滩面积系数、适宜游乐水域指数、主体功能度指数、景观多样性系数、景观变化指数等评估指标,评估了营口月亮湾海岸空间整治效果。结果表明:营口月亮湾沙滩养护工程实施后沙滩面积大幅增加,沙滩面积系数为2.44,适宜游泳嬉水娱乐区面积略有增加,适宜游乐区指数为1.10。海岸空间整理工程实施使月亮湾海岸游乐功能分区明显,月亮湖公园、高尔夫休闲区、山海广场区、农业生态旅游度假区和滨海嬉水观光区主体功能度指数分别达到0.89、0.76、0.68、0.65和0.77。海岸景观美化工程整体改变了海岸景观格局,使各功能分区海岸景观多样性提高,海岸景观格局更为优化,总体景观多样性系数达到1.13,景观变化指数达到0.30。 相似文献
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An examle of satellite monitoring of the large-scale dynamics of the eastern sector of the tropical Atlantic Ocean in April 1990 is considered. As the satellite-derived data, a series of averaged 5-day maps of the remote data on the upper ocean temperature field obtained from satellites of the NOAA series was used. The profundity of the effect of the satellite data is estimated. Recommendations are provided. for selecting the regions most appropriate for rapid analysis of the circulation using satellite data.Translated by Mikhail M. Trufanov. 相似文献
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景观指数是衡量区域景观质量的重要参数,也是进行区域生态规划、管理和恢复的重要信息依据。针对传统已有的矢量地图信息源及Excel、SPSS软件在景观指数计算中存在的不足和不便之处,研究了在ENVI4.2下,基于高分辨率SPOT-5遥感影像的自动景观分类及Fragstats3.3软件支持下的景观指数自动提取的计算方法,以屈原农场为例进行了实验研究,制作了景观现状图和计算部分景观指数。实验表明:该方法对景观质量的评价信息获取效率高、时效性强,通过快速分析与评价手段,可以大大地促进区域进行规划、管理和恢复的科学性和可操作性。 相似文献