Imagery sources are fused into a single global database with a Google acquires imagery from many different sources with manyĭifferent file formats, projections and spectral characteristics.
Since our database is constantly being updated, weĬannot state a specific resolution for any geographic region. Meter resolution for most of the earth's surface, with a global base Our imagery varies from sub-meter resolution in major cities to 15 Used for any navigational or other purpose requiring any accuracy These are provided for entertainment only and should not be Google makes no claims as to the accuracy of the coordinates in GoogleĮarth. This is why Google has that disclaimer about accuracy:
All of which may vary in their original resolution and quality of the above processes, so right off there is no single accuracy measurement. Now let's put that all into Google Earth, which is providing you a seamless interface to multiple original sources. On top of which, you're looking at errors introduced by (re)projection. Now let's get that into GIS, which requires both orthorectification and georeferencing. If the resolution of an image is a pixel is 1m, and you are zoomed in far enough to see individual pixels (original, not resampled for display purposes), you can measure to within +/- 1m. Let's start by taking Google Earth and even GIS out of the equation and only consider how accurate a measurement on an image can be. How accurate are measurements in Google Earth?.
0 kommentar(er)
