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What does raster cell size mean?
Spatial Resolution
Raster Resolution or “Cell Size” Cell size = Spatial Resolution: the dimension of the area covered on the ground and represented by a single pixel (e.g., 10m). A LandSat image has a resolution of 30 meters which means each pixel is about 90 feet by 90 feet square.
Why it is useful for rasters to be square rectangular?
When an input raster has rectangular cells, the data will be processed by Spatial Analyst in such a way that the output will have square cells. It is important to understand how the cell size and extent are changed and how the values of the original cells are handled.
What is raster scale?
Used to change the proportionate dimensions of an image. To scale an image, use an Active Scale or 3 Points Scale method. The Scale Raster tool adjusts the origin, pixel size, and dimensions of the image. The number of lines and pixels do not change.
When to resample raster to coarser resolution?
On execution, the input raster will first be resampled to the coarser resolution, then the tool is applied. When performing analysis, make sure you are asking appropriate questions of the cell size. For example, it is unlikely you will study mouse movement when the cell size is 5 kilometers.
The higher the resolution of a raster, the smaller the cell size and, thus, the greater the detail. This is the opposite of scale. The smaller the scale, the less detail shown. For example, an orthophotograph displayed at a scale of 1:2,000 shows more details (appears zoomed in) than one displayed at a scale of 1:24,000 (appears zoomed out).
How is the size of a cell related to resampling?
Five-kilometer cells might be more applicable when studying the effects of global warming over the earth. To find the value each cell should receive on the resampled output raster, the center of each cell in the output must be mapped to the original input coordinate system.
Spatial resolution refers to the dimension of the cell size representing the area covered on the ground. Therefore, if the area covered by a cell is 5 x 5 meters, the resolution is 5 meters. The higher the resolution of a raster, the smaller the cell size and, thus, the greater the detail.