![]() ![]() If you can find the corresponding image in the catalog, then you can see all the metadata, including which satellite and what resolution.įor the person who posted the bounty, yes, the resolution keeps improving in most places. If you really want to dig in, you can go to the company's online imagery catalog, look in your desired location, search for images around the date provided, and try to find an image that looks the same (similar colors, cloud patterns, etc.). If it's from DigitalGlobe, then it's most often 0.5m. though for the aerial data that may not help as a copyright is often not listed. There is a good suggestion in previous answers, that you zoom way in and look at the copyright strings, as that will often tell you at least what company the data came from (as well as the acquisition date listed in the status bar). More generally, find an object that you know the approximate size of, and see about how many pixels it's covered by, and do the math. If you can clearly make out the pillars, and start to see the side-view mirrors on the car, then you're most likely looking at aerial data in the 0.15m range. If the windshield is pretty clear, but you can only barely (or not quite) make out the frame pillars along the sides of the windshield, then you're probably looking at 0.5m satellite imagery. ![]() If you can clearly make out the shapes of cars, but their windshields are poorly defined, then it might be 1m from Ikonos. If roads and house roofs look like they are 2-5 pixels wide, then you are probably seeing SPOT's 5m or 2.5m products. Here are some fun rules of thumb I use to quickly estimate the resolution of what I'm looking at, by zooming in on cars. There is no tool that will tell you the resolution of Google Earth's imagery in any specific location. Finally, there are just a few tiny spots around the world where Google Earth shows data collected by citizen scientists (through the Public Lab), using cameras on kites and balloons, which can get down into the few centimeters per pixel range. In much of North America, Europe, Japan and some other places, you'll find even higher resolution images which generally come from aerial systems (cameras on airplanes), and a lot of that data in Google Earth is at about 0.15m resolution. That's about the limit for satellite data, though a few places are staring to get data from newer satellites (including WorldView-3) at around 0.3m. Then you get down to the really high-resolution satellites, including Digital Globe's WorldView-1/2/3 series, GeoEye-1, and Airbus' Pleiades, all of which provide data at around 0.5m resolution. Next you can still find some Ikonos data in a few places, at about 1m resolution. There are many rural areas especially in Africa, where broad coverage is provided by the SPOT satellites, which produce anywhere from 10m to 1.5m resolution. Zooming in, you'll start to get high-resolution in most places. When you zoom out, you will see the nice, pretty global coverage produced from a mosaic of many Landsat scenes, which have a native resolution of ~30m (~15m pan-sharpened). Software emulation lowers image quality and rendering speed.The resolution of imagery in Google Earth varies depending on the source of the data. If your GPU supports only DirectX and you are a Linux or OS X user, however, Google Earth will emulate an OpenGL-compatible GPU in software. ![]() If your GPU supports OpenGL, Google Earth should render graphics with the same speed and quality of a DirectX-compatible GPU. Although the OpenGL API is freely available to use without licensing restrictions, many GPU manufacturers choose to provide direct hardware support for DirectX only. Since the DirectX API is designed for PCs running Windows operating systems only, Linux and Mac OS X users must run in OpenGL mode. Nevertheless, both the minimum and recommended system requirements for Google Earth specifically include a graphics card with DirectX9 support. If your system crashes or performs poorly in one mode, Google recommends you switch to the other mode. ![]() You can configure Google Earth to operate in either DirectX or OpenGL rendering modes. Google does not specifically recommend either DirectX or OpenGL for Google Earth. ![]()
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