The choices selected from these submenus will often bring up dialog boxes that allow you to enter information or set parameters relating to the ENVI function you have selected. Note that most menus in ENVI windows and dialog boxes appear as buttons. Often the button label changes to reflect the currently-selected menu option. This file format permits ENVI to use nearly any image file, including those that contain their own embedded header information. BSQ is the simplest format, with each line of data followed immediately by the next line of the same spectral band.
BIP format provides optimal spectral processing performance.
Images stored in BIP format have the first pixel for all bands in sequential order, followed by the second pixel for all bands, followed by the third pixel for all bands, etc., interleaved up to the number of pixels. BIL format provides a compromise in performance between spatial and spectral processing and is the recommended file format for most ENVI processing tasks. Images stored in format have the first line of the first band followed by the first line of the second band, followed by the first line of the third band, interleaved up to the number of bands. Subsequent lines for each band are interleaved in similar fashion. The separate text header file provides information to ENVI about the dimensions of the image, any embedded header that may be present, the data format, and other pertinent information.