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ENVI does not directly support THEMIS qub data sets. You might be able to read them in as binary.
The image parameters that you need to enter manually in ENVI are embedded in the header of the THEMIS data. If you are on a Windows machine, you will need to view the header information in a text editor (for example, Notepad or Wordpad). If you are on a UNIX machine, you can use the commands "less filename.qub" or "cat filename.qub | more" to view the necessary text.
Once you are looking at the header information of the .qub file, scroll down until you see the section entitled:
OBJECT = SPECTRAL_QUBE
/* QUBE Structure */
AXES = 3
AXIS_NAME = (SAMPLE, LINE, BAND)
/* Core Description */
CORE_ITEMS = (320, 7184, 10)
CORE_NAME = "CALIBRATED_SPECTRAL_RADIANCE"
CORE_ITEM_BYTES = 2
CORE_ITEM_TYPE = SUN_INTEGER
The primary field you need to note is:
(1) CORE_ITEMS is a three-element array that corresponds to the image's number of samples, lines, and bands (as referenced in the AXIS_NAME field). In this example, this image has 320 samples, 7184 lines, and 10 bands.
You also may need to note:
(2) CORE_ITEM_BYTES corresponds to the the data type. A value of "2" here equals 2-byte integer data. A value of "1" would denote byte data.
(3) CORE_ITEM_TYPE corresponds to the byte storage of the data. Sun (IEEE) machines are "Big Endian" machines, meaning that multiple byte integers are stored in memory beginning with the most significant byte. But Windows (Intel) machines are "Little Endian", meaning that multiple byte integers are stored in memory beginning with the least significant byte. You may also see this field set to MSB_INTEGER. MSB stands for "most significant byte." In the example here, you would set the byte order to IEEE in the ENVI header dialog.
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