HJ_Radio_Correction.sav is a user function that will convert HJ satalite DN values to floating point radiance values (W.m-2.Sr-1.um-1) using the gain and offset information found in the associated XML metadata file (.xml), and layersatcking four bands into one muti-bands layer file.
you can see "HJ radio Correction" menu under Basic Tools menu if you put this sav file into \ITT\IDL##\products\envi##\save_add\
if you have some suggust,please connect me ,my emial address is nxqx@tom.com,or nxqx@21cn.com.

This is a user function that will convert SPOT DN values to floating point radiance values (W.m-2.Sr-1.um-1) using the gain and offset information found in the associated dimap metadata file (.dim). For SPOT data, ENVI's Apply Gain and Offset tool cannot perform the calibration because SPOT uses the equation: L = X/A + B where: • L is the resulting physical value expressed in PHYSICAL_UNIT • X is the radiometric value at a given pixel location as stored in the raster file (unitless). • A is the gain (PHYSICAL_GAIN) • B is the bias (PHYSICAL_BIAS) This is different than ENVI's gain/offset correction which uses the following equation: L = X*A + B The user function is placed in the Basic Tools -> Preprocessing -> Calibration Utilities menu. The calibration is based on information provided by SPOT imaging: http://www.spotimage.fr/dimap/spec/dictionary/pdf/SPOT%20Scene.pdf

*Updated August 17, 2010*  - User's now can choose to calibrate to radiance or TOA reflectance for SPOT DIMAP data.  Added in a Top of the Atmosphere (TOA) calculation for SPOT DIMAP files.  Additional parameters extracted from the DIMAP metadata (.DIM) include the SOLAR_IRRADIANCE_VALUE, SUN_ELEVATION, and IMAGING_DATE.  The Earth-Sun distance table comes from JPL Ephemeris (DE405) data (http://ssd.jpl.nasa.gov/?horizons).  The .DIM must be selected for the tool to work.

RevolutionIDL.zip

[Update - July 22, 2010] -- Revolution IDL 2.8 supports IDL 8.0

Revolution IDL unleashes the power of the IDL Object Graphics architecture by providing a high-level graphical user interface that allows the user to visualize data in a variety of ways, changing properties, positioning objects in 3D, and much more.

Object Graphics in IDL are very powerful, but writing the code necessary to produce even simple results is quite time consuming, which limits their usability. Revolution IDL helps working with complex 3D graphics by combining these four main components: 1. A powerful and intuitive 3D-based environment. 2. GUI access to object properties and hierarchy. 3. Algorithms to produce advanced graphics. 4. A source code generation mechanism that extracts the IDL program for all the graphics created with the application. You will find this 3D environment powerful enough to make it your regular graphics environment. The IDL source code generation capability will allow you to take any scene that you create and embed it into your own IDL programs.

[Update - July 22, 2010] -- Adopting IDL 8.0 new Graphics API

Whether you are new to IDL, or already have some experience with the language, this tool will assist you in creating basic programs that are easily reusable. Select among a variety of data sources, processing, and visualization options and the Source Code Generator will produce a simple program that does what you want. Each choice comes with a few links to further information in the documentation. You can also run all the programs for testing purposes, and save them for use in your own application. In addition, it brings together existing examples of basic widget programs as a quick reference of how to create GUI interfaces in IDL.