When does Google Earth Engine perform nearest neighbor resampling?
As noted in the Projections doc, Earth Engine performs nearest neighbor resampling by default during reprojection. You can change this behavior with the resample () or reduceResolution () methods.
When to use resampling instead of reprojection?
Suppose that instead of resampling during reprojection, your goal is to aggregate pixels to larger pixels in a different projection. This is useful when comparing image datasets at different scales, for example 30-meter pixels from a Landsat-based product to coarse pixels (higher scale) from a MODIS-based product.
How does reduceresolution work in Google Earth Engine?
The weights of pixels used during the reduceResolution () aggregation process are based on the overlap between the smaller pixels being aggregated and the larger pixels specified by the output projection. This is illustrated in Figure 4. Figure 4.
Where does the data in Earth Engine come from?
An error occurred while retrieving sharing information. Please try again later. Earth Engine is unlike traditional image processing, GIS or other desktop software used for geospatial data analysis. Algorithms you create in Earth Engine run in the Google cloud, distributed over many computers.
How are pixels used in reduceresolution in Google Earth?
The weights of pixels used during the reduceResolution () aggregation process are based on the overlap between the smaller pixels being aggregated and the larger pixels specified by the output projection. This is illustrated in Figure 4. Figure 4. Input pixels (black) and output pixel (blue) for reduceResolution () .
How is the weight of a pixel calculated in Google Earth?
In the diagram, the output pixel has area a, the weight of the input pixel with intersection area b is computed as b/a and the weight of the input pixel with intersection area c is computed as c/a. This behavior can result in unexpected results when using a reducer other than the mean reducer.
How does Google Earth Engine scale an image?
The data are aggregated until the entire image fits within a 256×256 pixel tile. When you use an image in your code, Earth Engine chooses a level of the pyramid with the closest scale less than or equal to the scale specified by your analysis and resamples (using nearest neighbor by default) as necessary.