Georeferencing means connecting the data to spatial coordinates. When you have imported raster data, BoundarySeer requires the size of the pixels and the coordinates of the raster. This information fixes the raster within the coordinate system specified on import. Once the raster is georeferenced, then BoundarySeer can overlay it with other files in the same coordinate space.
GRID ASCII files, DEM, DOW, DRG, and geoTIFF files include georeferencing information in the data or in the header file. Other raster data files, such as BIL, BIP, BSQ, BMP and JPEG, do not always contain this information. For these data files, the raster must be georeferenced.
You may encounter the Georeferencing dialog in the data import process, or you can access it from the "Data" menu or by right clicking in the "Data" tab on the BoundarySeer project window.
Choose the data set to be georeferenced from the pull-down menu.
Choose which type of georeferencing information you will enter. Either is sufficient to georeference the data.
Origin and cell size. You can georeference either by entering the coordinates of the origin of the raster (the minimum X and Y coordinates of the grid edge) and the grid cell size. BoundarySeer georeferences the entire data set from this information.
Raster data boundaries. You need to enter the coordinates for the northern, eastern, southern, and western edge of the data set. This data is essentially the minimum and maximum X coordinates and the minimum and maximum Y coordinates. BoundarySeer calculates cell size from this information, based on the number of columns in your data.
If you choose to georeference using the raster data boundaries, BoundarySeer calculates the x and y cell sizes under the assumption that all pixels in the raster are the same size and shape. If you georeference using geographic coordinates (latitude-longitude), this assumption will distort the raster somewhat.
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