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The BIL, BIP and BSQ raster data formats were originally developed by USGS for CCT tape formats for Landsat satellite data from 1972 on. These are simple uncompressed binary files representing a raster of one or more image bands, accompanied by an ASCII header file (*.hdr) with image information. The main file extension depends on the format, or storage sequence:
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The file format was documented by ESRI online. (PDF version here) and supports integer (8,16 or 32 bit) pixel values in signed or unsigned format, in either little- or big endian storage order. The 1- and 4- bit integer pixel formats have not been implemented (yet) as they seem less useful for FEWS, but the rest of the documentation is fully implemented.
BIL files in FEWS
In the Public Interface (PI interface) of FEWS, an implementation of the BIL format is also provided, as documented here.
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