NC Orthoimagery 2024-2027 - NDVI

NOTE: DO NOT DOWNLOAD THE IMAGERY BY USING THE MAP OR DOWNLOAD TOOLS ON THIS ARCGIS HUB ITEM PAGE. IT WILL RESULT IN A PIXELATED ORTHOIMAGE. INSTEAD, DOWNLOAD THE IMAGERY BY TILE OR BY COUNTY MOSAIC (2010 - current year). 2024-2027 project areas The NC Orthoimagery Program collects and produces 6-inch (15cm) orthoimagery on a 4-year cycle. Approximately a quarter of the state is flown each year to develop streaming imagery services, 5,000' by 5,000' tiles, and compressed single-file county mosaics. Beginning in 2020, the State started collecting a fourth band (near infrared) of imagery which, when combined with the other 3 bands of red, green, and blue, opens new possibilities for exploration and analysis. This service contains 4-band (RGB+NIR) imagery collected by the NC Orthoimagery Program for any given area of North Carolina between 2020 and 2023 and is depicted using the Normalized Difference Vegetation Index (NDVI). The imagery has a pixel resolution of 6 inches with an RMSE of 1.0 ft X and Y. The compression method (DEFLATE) used for this imagery maintains the individual pixel values so that this data is suitable for analyses. This data is also available as WCS and WMS services. About NDVI NDVI is useful for measuring the quality, density, and amount of vegetation in a particular area. It is a single band dataset that represents vegetation health, based on the difference between the red and near infrared bands. Red and orange pixels represent areas with no vegetation. Yellow pixels represent areas with low to moderate vegetation. Green pixels represent areas with high vegetation density and health. This data is provided as a web service only (no download). Other Types of Analyses and General Viewing Other services are available for this same data that support custom analyses or are pre-configured for CIR and are available in a variety of formats. For general viewing, the 3-band NC Orthoimagery 2024-2027 image service may offer better appearance and performance. This is available in REST and WMS formats. To find specific dates the images were captured use the imagery dates app or download the data. Viewing the latest imagery Several web services are also available that depict the latest imagery for any location in the state. These support general viewing and raster analysis and are offered in various protocols including Esri (e.g. REST, SOAP) and OGC (e.g., WMS, WFS, WCS). These can be found by searching using the terms "orthoimagery" and "latest." To help determine which is most suitable, refer to this guide.

注意：请勿通过此ArcGIS Hub项目页面中的地图或下载工具下载影像，此操作将得到像素化的正射影像（orthoimage）。请通过分幅影像或县域镶嵌影像（2010年至今）进行下载。

2024-2027 项目区域
北卡罗来纳州正射影像项目（NC Orthoimagery Program）每四年为一个周期采集并生成6英寸（15厘米）正射影像（orthoimagery）。该项目每年覆盖该州约四分之一的区域，以搭建流式影像服务、5000英尺×5000英尺分幅影像以及压缩单文件县域镶嵌影像。2020年起，该州开始采集第四波段——近红外（near infrared）影像，与红、绿、蓝三个波段结合后，可为探索与分析开辟全新可能。

本服务包含2020至2023年间北卡罗来纳州任意区域的4波段（RGB+近红外）影像，以归一化植被指数（Normalized Difference Vegetation Index, NDVI）进行可视化呈现。该影像的像素分辨率为6英寸，X、Y方向的均方根误差（RMSE）为1.0英尺。本影像采用的DEFLATE压缩算法可保留单个像素的数值，因此本数据适用于各类分析工作。本数据同时支持通过WCS与WMS服务访问。

关于归一化植被指数（NDVI）：
NDVI可用于测量特定区域内植被的质量、密度与覆盖量，是基于红波段与近红外波段差值构建的单波段数据集，用于表征植被健康状况。其中红色与橙色像素代表无植被区域，黄色像素代表植被覆盖度低至中等的区域，绿色像素代表植被密度与健康状况俱佳的区域。本数据仅以Web服务形式提供（不支持直接下载）。

其他分析类型与常规浏览：
针对本数据集另有多项服务，可支持自定义分析，或预配置为彩红外（Color Infrared, CIR）格式，并提供多种格式支持。若仅用于常规浏览，2024-2027版3波段北卡罗来纳州正射影像服务可提供更优的视觉效果与性能，该服务支持REST与WMS格式。
如需查询影像拍摄的具体日期，可使用影像日期应用程序或下载对应数据。

最新影像浏览：
另有多项Web服务可用于可视化该州任意地点的最新影像，支持常规浏览与栅格分析，采用多种协议，包括Esri协议（如REST、SOAP）及OGC协议（如WMS、WFS、WCS）。可通过搜索“orthoimagery”与“latest”关键词查找此类服务。如需选择最适配的服务，可参阅本指南。