Reducing your images in size below this limit will avoid scaling. Images larger than 16384 by 16384 pixels will be scaled down. If an image does not contain georeference data, you will need to open the image and add the information manually, as described in Manually Georeferencing Images below. Drag and drop them into the GIS Data, Maps and Photos folder in Leapfrog Geo.Īll images will be imported and added to the GIS Data, Maps and Photos folder. In the File Explorer, select all the files you wish to import.The images will be imported and added to the GIS Data, Maps and Photos folder. Navigate to the folder that contains the files you wish to import. Right-click on the GIS Data, Maps and Photos folder and select Import Map.There are two ways to import multiple images: The image will be imported into the GIS Data, Maps and Photos folder. Once you have georeferenced the image, click Import. See Manually Georeferencing Images below. If the image does not contain georeference data, the Import Map window will be opened so you can add the georeference data.If the image contains georeference data, it will be imported into the GIS Data, Maps and Photos folder.Navigate to the folder that contains the image, select the file and click Open. To import a single image, right-click on the GIS Data, Maps and Photos folder and select Import Map. The rest of this topic describes how to work with imported images in Leapfrog Geo. When you switch back to the scene, you can see the georeferencing markers: You can see these markers in the scene when you double-click on an imported image, which opens a tab that has tools for cropping the image and editing its georeference data: In Leapfrog Geo, three markers (, , ) are used to display the georeference data for imported images. You can, however, edit the information if you need to. If images being imported contain georeference data, that information is assumed to be correct. Graphics Interchange Format Files (*.gif).Ask for an uncompressed or lossless image in addition to any lossy, compressed images they provide.Image formats Leapfrog Geo supports include: This can make it difficult to precisely locate features on the map, since edges may spread out over several pixels. One drawback of image compression, especially the wavelet compression used by MrSID imagery, is that it can produce ringing artifacts around the edges of features. Orthoimages are large files, and you may receive a file that has been compressed to reduce its file size. Your contract with the imagery provider should specify the level of accuracy to expect across the entire image. They will also add the georeferencing data, the calibration points that allow ExpertGPS to determine the latitude and longitude of every pixel on the image. Overhead imagery needs to be ortho-rectified by the imagery provider to remove the distortion caused by the aerial camera not pointing straight down when the photo is taken. The accuracy you get in ExpertGPS depends on the quality of the ortho-rectification done by the imagery provider and the correctness of the calibration points (tie points) given in the GeoTIFF or. If they don’t, there are free programs to extract a. tfw calibration file with the GeoTIFF – this would be standard if they were providing imagery for use in ArcGIS, so they should be used to it. It should be relatively painless for the consultant or the imagery provider to also provide a. ExpertGPS will treat it as an uncalibrated TIFF, meaning you’ll have to do the calibration by hand. Last but not least…when importing an image to ExpertGPS what format would yield the absolute best accuracy we could hope for? How to use GeoTIFF imagery in ExpertGPS?ĮxpertGPS doesn’t have the ability to read the projection and georeferencing data out of a GeoTIFF at this time, although it’s high on my list of to-do features for GIS users. My question to you is does ExpertGPS software support the beforementioned format and or if there is a better format to employ in your opinion.Īs a backup thought I have requested we receive the image in various formats to make sure all of our software would be compatible with it…. The District is considering the purchase of a new GEOTIFF aerial image of the district boundaries for mapping of the infrastructure…the consultant we have been in contact with is advising us to purchase the image in this format for its exceptional horizontal accuracy.
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