Band Interleaved .BIL, .BIP, .BSQ File Description


The Band Interleaved filter imports and exports lattice data as .BIL, .BIP, and .BSQ raster data sets.


File Description

Band Interleaved by line .BIL format is a common format for distributing satellite image data and organizing image data for multiband images. Band Interleaved by Pixel .BIP, and Band Sequential .BSQ. The .BIL, .BIP, and .BSQ are formats produced by remote-sensing systems. The primary difference among them is the technique used to store brightness values captured simultaneously in each of several colors or spectral bands. The data values are stored in a simple binary raster.


The .BIL, .BIP, and .BSQ files are not in themselves image formats but are schemes for storing the actual pixel values of an image in a file. These files support the display of single and multiband images. The .BIL file is an uncompressed file containing the actual pixel values of an image. It can handle black and white, grayscale, pseudocolor, true color, and multi-spectural image data. BIL data stores pixel information in separate bands within the file, so that the user can choose to display just one specific band in a multi-band image.


File Format

The .BIL, .BIP, and .BSQ files are binary files, and they must have an associated ASCII header .HDR file. This header file must have the same filename as the .BIL, .BIP or .BSQ, and only its file extension differs. This header file contains data about the image such as the number of rows and columns in the image and latitude and longitude. There are no header or trailer bytes imbedded in the image. The data are stored in row major (all the data for row 1, followed by all the data for row 2, etc.). A header file is an ASCII text file containing the size and coordinate information for the raster data.


There are four image description files (ASCII text file format) that can accompany the BIL data: a header .HDR file, a statistics .STX file, a resolution file .BLW, and a color file .CLR


The header file .hdr describes the nature of the image data, through the use of keywords and values.


The statistics file .stx is an optional file that describes the image statistics for each spectral band. It records the minimum and maximum pixel values, the mean, the standard deviation, and the two linear contrast stretch parameters.


The resolution file .blw describes the height and width of each cell and the coordinate position of the top left cell of the data. It gives the Resolution information with the following lines:

resolution in x-dimension
rotation factor (always zero for GPW)
rotation factor (always zero for GPW)
resolution in y-dimension
x-coordinate of the center of the upper-left cell
y-coordinate of the center of the upper-left cell


The color file (.clr) is an optional file that describes the image colormap (this file type is not used in the GPW data).


File Name Extensions

.BIL, .BIP, and .BSQ


Import Method

Choose the File | Import command.


Import Options

Specify the import options in the Lattice Import Options dialog.


Export Method

Select a lattice or image module and choose the File | Save Data command.



See Also

File Format Chart

File | Import

File | Save Data

Lattice Import Options