Code Library

The MODIS Conversion Toolkit (MCTK) is a plugin for ENVI that can ingest, process, and georeference every known MODIS product (currently 143) through your choice of an easy-to-use interactive widget interface or a fully-accessible programmatic interface. Supported products include: - Level 1A Uncalibrated Radiance - Level 1B Calibrated Radiance - Level 2 Swath - Level 2G, Level 3, and Level 4 Grid The interface allows you to take a "cafeteria" approach to MODIS data by providing a list of all available datasets within a file, from which you can choose the ones to process. The ENVI equivalents of MRT and MRTSwath are built in as well, which means that you can input a file, have its contents converted to scientifically meaningful values, and then project those contents into the coordinate system of your choice--all within one interface. Bow tie correction is also available for all swath products. The user guide (included with the plugin) contains:

• Descriptions of how the plugin interacts with each major MODIS product category
• Screen captures to aid in using the interactive version
• A complete explanation of the programming interface with fully functional sample programs for each major MODIS product category.
• A list of all supported MODIS products

Updates will be posted occasionally; comments and suggestions are welcome. Please check the displayed build date on your current version of MCTK against the most recent upload date listed below. If your version does not show a build date, or the date is earlier than the most recent one listed below, please click Download to obtain the latest version.

New version created on 08/25/11:  Added support for MCD12Q1, MCD12Q2, and MCD12C1 land cover products.
New version created on 10/01/11:  Bug fixes for handling of HDF scientific datasets (SDs); saturated pixels in Level 1B products with an integer value of 65533 are now set to maximum possible radiance value of 32767 prior to conversion; binary recompiled in 32-bit IDL to mitigate 64-bit Linux compatibility issues

The Hyperion Tools plugin is designed to facilitate the use of Hyperion data in ENVI. Its most basic functionality is to covert Level 1R HDF and Level 1G/1T HDF and GeoTIFF datasets into ENVI format files that contain wavelength, full width half maximum, and bad band information. Also included are options specific to each input dataset format that further aid in using Hyperion data within ENVI.

Version 2.0 of the toolkit runs significantly faster, includes support for the new Level 1R format (L1R + AUX), and comes with an API that enables batch processing.  Please consult the PDF Installation and User Guide for more information.

The Max/Min value image tool calculates the maximum and minimum values of an image stack.  The max/min values are generated for each pixel from all of the bands of the input file.  You can think of the values as the max/min values of a z-profile (spectrum).  The returned file includes two bands called 'Max value' and 'Min value'.  This tool uses IDL's MAX function to perform the calculation.

Place the max_min_value.sav in the \envixx\save_add directory and restart ENVI.  A new button called 'Max/Min value image' should appear under Basic Tools ->Statistics. 

*Updated 12/21/2010 to pass on georeferencing

This toolkit is specifically designed to work with  HJ-1A and HJ-1B Level 2 HDF5 or GeoTIFF files. The default output is a ENVI standard format file. Optional processing choices vary by input format. Including the HDF5 data viewer and XML data viewer.
1.Run the save file directly
2.Copy the save file to the folder "save_add",like "C:\Program Files\ITT\IDL##\products\envi##\save_add"
Then you can see the menu :  File→Open Extenral File→HJ-1→HJ1A/1B

 This program serves as a guide to modify the transformation parameters using default ENVI. The user can create their own parameters or use those that come included in ESRI Projection Engine and are not visible through the ENVI menu.

This routine allows the user to load the set of global parameters of Chile that by default are configured in ESRI Projection Engine for ENVI. In the case of Chile, the mapping is referred to the systems PSAD56, SAD69 and WGS84.

The tools Convert Map Projection and Convert Projection Layer by default made the transformation between Coordinate Systems through ESRI Projection Engine, but these transformations do not fit completely to Chile.

This .pro allows viewing directly the transformations from de ENVI menu options that can be used.

[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.

This user function simply displays the contents of an ASCII text file. You can switch the view between an equal-spaced font and the current system font.

To install this program simply download the file and move it to the "save_add" subfolder of the ENVI installation:

ENVI 4.3 and older:

- Windows: C:\RSI\IDL##\products\envi##\save_add\

ENVI 4.4 and newer:

- Windows: C:\Program Files\ITT\IDL##\products\envi##\save_add\

Once this is accomplished, restart ENVI and a 2 new menu items will be added to the software:

- MAIN MENU : File > Launch Web Map Servers

- DISPLAY MENU : Tools > Launch Web Map Servers...

This program provides an interface for loading maps and imagery from 6 free web map servers (Google Maps, Microsoft Bing Maps, OpenStreetMap, TerraServer, MapQuest, and TerraServer-USA) using a geolocation coordinate (latitude & longitude). This program can be executed in stand-alone IDL or from an interactive session of ENVI, and it is only supported on Windows.

This program supports tabbing, so you can select a tab and navigate to its GUI components using the Tab key, or navigate to neighboring tabs using the left (<--) and right (-->) arrow keys. Also keep in mind that you can right-click within the browser window and use the standard Internet Explorer context menu, which contains useful tools such as "Back", "Forward", "Add to Favorites", and "Print".

If launched from ENVI, either the center coordinate of the selected dataset file or the current zoom window display pixel location are used for the initial latitude and longitude. This program can also be executed within IDL, IDL Runtime, or the IDL Virtual Machine. When launching this program from an interactive IDL> command prompt, the user has the ability to specify initial latitude and longitude using the LAT and LON keywords :

IDL> launch_web_map_servers, lat = 40.02, lon = -105.24

When using IDL 6.2 or newer, this program can also be launched (with or without arguments) from the MS-DOS Command Prompt within IDL Runtime using the following syntax :

C:\> idlrt Launch_Web_Map_Servers.sav -args latitude longitude

For example :

C:\> idlrt "C:\Launch_Web_Map_Servers.sav" -args 40.02 -105.24

This IDL application is a simple XML Viewer. It allows a user to visualize a XML file in a tree structure and search the file by its Elements, Content, Attribute or their Value.

• To run XML Viewer in IDL the file xmlviewer.sav can be restored and then run xmlViewer.
• To run XML Viewer in ENVI + IDL copy the file xmlviewer.sav to the save_add subfolder of the ENVI installation. The ENVI menu bar will contain a new pull down menu option File -> Launch XML Viewer.

Note, currently XML Viewer does not contain any file editing/saving features. It is intended to be quick visualization tool to ease the parsing and reading of xml files as they are becoming more ubiquitous as input files to many engineering applications.

To use this program is very simply: download the file and move it to the "save_add" subfolder of the ENVI installation.

Once this is accomplished, restart ENVI and a new menu item will be added to the software:
Basic Tools→Preprocessing→General Purpose Utilities→ Landsat ETM+ Destripe

The purpose of this program is to destripe the Landsat7 ETM+ image's tripe for the .It used two interpolate methods to process the Landsat7 ETM+ image and corresponding Masking image.Also the program can be used to destripe other image which have masking file.

After downloading the file for this toolkit copy the .sav file to the "save_add" subfolder of the ENVI installation:
ENVI 4.4 and newer:
- Windows: C:\Program Files\ITT\IDL##\products\envi##\save_add\
- Mac OS X: /Applications/itt/idl##/products/envi##/save_add/
- UNIX/Linux: /usr/local/itt/idl##/products/envi##/save_add/

Once this is accomplished, restart the ENVI software and some new menu items will be added to the ENVI menu system:

File->Open External File->Cosmo SkyMed

Radar->Open/Prepare Radar File->COSMO SkyMed Utilities->View Basic COSMO SkyMed Header
Radar->Open/Prepare Radar File->COSMO SkyMed Utilities->View Extend COSMO SkyMed Header
Radar->Open/Prepare Radar File->COSMO SkyMed Utilities->COSMO Meta to XML
Radar->Open/Prepare Radar File->COSMO SkyMed Utilities->Prepare data for SARSCAPE

Basic Tools->Preprocessing->Data-Specific Utilities->COSMO SkyMed->Georeference COSMO SkyMed (DGM)
Map->Georeference COSMO SkyMed (DGM)

Note:
The georeference function is just using the four corners of the image plus the central point, so the accuracy of the function is limited.
 

This toolkit provides function to read and import COSMO SkyMed data (Level 1A up to Level 1D including GTC), and some utilities to extract header information, additional functions and capabilities such as precise georefencing, filtering, interferometry processing are available through the SARscape product suite.

The IMAGE_SAVGOL program applies the Savitzky-Golay smoothing filter to multispectral and hyperspectral images.  The filer is defined as a weighted moving average with weighting given as a polynomial of a certain degree.  The returned coefficients, when applied to a signal (spectrum in this case), perform a polynomial least-squares fit within the filter window. This polynomial is designed to preserve higher moments within the data and reduce the bias introduced by the filter. The filter can use any number of points for this weighted average and works especially well when the typical peaks of the signal are narrow. The heights and widths of the curves are generally preserved.  For more information see the IDL help regarding the SAVGOL filter.

Place the image_savgol.sav in the \envi47\save_add directory of your ENVI installation.  A new button will appear under the Filter menu called 'Apply Savgol filter'.

To install this program simply download the file and move it to the "save_add" subfolder of the ENVI installation:

ENVI 4.3 and older:
     - Windows    :  C:\RSI\IDL##\products\envi##\save_add\
     - Mac OS X   :  /Applications/rsi/idl_#.#/products/envi_#.#/save_add/
     - UNIX/Linux :  /usr/local/rsi/idl_#.#/products/envi_#.#/save_add/

ENVI 4.4 and newer:
     - Windows    :  C:\Program Files\ITT\IDL##\products\envi##\save_add\
     - Mac OS X   :  /Applications/itt/idl##/products/envi##/save_add/
     - UNIX/Linux :  /usr/local/itt/idl##/products/envi##/save_add/

Once this is accomplished, restart ENVI and a new menu item will be added to the software:

Map > Map Distance Converter

The purpose of this program is to provide a GUI interface for map distance conversion between decimal degrees lat/lon and meters, and vice-versa, using a wide variety of ellipsoids. This program is useful to determine the appropriate pixel size when converting data from a fixed-angle (e.g. Geographic Lat/Lon) projection to a fixed-length projection (e.g. UTM). It is important to note that this program performs a DISTANCE conversion ... not a fixed map coordinate conversion. There is already a map coordinate conversion in ENVI under the "Map" menu.

MULTITHREAD.PRO provides a means to make use of multiple CPUs on a single computer. While some of the IDL routines are already able to parallel process over several CPUs, it is not possible with all IDL commands, or even user written routines.

This procedure uses the IDL_Bridge objects to create multiple IDL session instances on the executing machine (one per CPU), copies the necessary variables to each session, executes a command that use those variables and then harvests and re-assembles the data for output.

For example, to calculate Z = X^2 + Y^2

X = FINDGEN( 10000L)
Y = X
multithread,'Z=x[i:j]^2 + y[i:j]^2', ['x','y'], ['z'], /WAIT

will return Z at the calling scope.

This routine is particularly useful for processing multiple files:

filenames = FILE_SEARCH('*.txt')
multithread,'process_files,filenames[i:j]', ['filenames'], /WAIT

where the user routine PROCESS_FILES would be executed for each of the files in the filenames variable.

These routines allow reading and writing frames (using standart Windows multimedia subsystem) from or into AVI files and reading frames from MPEG, QT or DVD files. Routines uses CALL_EXTERNAL and Dll for Windows platform (IDL5.2, 5.5, 6.1). Some fast preprocessing (deinterlacing, spatial and temporal smoothing, sharpening, color correction, levels control, non-linear editing, and many more) is possible. AVI writing is possible using options (codec, quality, keyframe interval, bitrate) or using compression dialog. Source code availible.

This is a user function that will calculate a 'natural color composite' image from SPOT and ASTER VNIR bands. The SPOT and ASTER VNIR bands contain green, red, and near infrared bands which can be combined in an RGB display to create a color infrared (CIR) composite. In order to create a 'natural' color composite (where vegetation appears green and water appears blue), simple band combinations of the green and NIR bands can be calculated to mimic the blue and green bands necessary to create the natural colors of the composite. This user function uses band combinations developed for SPOT HRV multispectral data which bands cover similar spectral ranges as ASTER VNIR data. The natural color composite image is generated using the following:

R = SPOT/ASTER band 2
G = (3 * SPOT/ASTER band 1 + SPOT/ASTER band 3)/4
B = (3 * SPOT/ASTER band 1 - SPOT/ASTER band 3)/4

where:
SPOT/ASTER band 1 = green
SPOT/ASTER band 2 = red
SPOT/ASTER band 3 = NIR

The user function generates a new 3 band image where band 1 should be displayed as red, band 2 as green, and band 3 as blue. Place the natural_color_composite.sav file in the save_add directory of your ENVI installation. A new menu button will be created under the 'Transform' menu called 'Natural Color Composite 'and has two selections - ASTER and SPOT. Selection of the ASTER button assumes the input file will be the ASTER 3-band VNIR file while selection of the SPOT button assumes the input file will be a 4-band SPOT file, which includes the SWIR band.

The Google Earth Super-Overlay Tool (GEST) allows you to take an image displayed in ENVI and view it at full spatial resolution in Google Earth. There is no limit on image size or type. As long as you can load your image to a display in ENVI, and that image has an associated map projection, you can use this tool. To install GEST, place the gest.sav file in your save_add directory and restart ENVI. To use:

1. Load an image to a display and apply any desired contrast enhancements. 
2. From within the display window, go to File->Save Image As->Google Earth Super-Overlay. 
3. Select a folder where you want the output to go. It is recommended that you set up an individual folder for each image you want to process. 
4. Provide an output KML filename. IT IS STRONGLY RECOMMENDED THAT YOU PLACE THIS FILE IN THE SAME DIRECTORY SPECIFIED IN STEP 3. 
5. Specify an image subset, if desired. 
6. Select the desired Google Earth Tile Size. The default is 512x512. 
7. Click Process. 

If the image you provided has RPC/RSM projection emulation turned on, GEST will automatically perform a baseline orthorectification to Geographic Lat/Lon. If the image has a standard projection, but it is not Geographic Lat/Lon, GEST will automatically perform a rigorous reprojection. The conversion process may involve building several pyramid layers, so please be patient. When the process is complete, you will see many KML and PNG files in the output folder you specified. THE ONLY FILE YOU HAVE TO INTERACT WITH IS THE KML FILE YOU PROVIDED THE NAME FOR IN STEP 4. Open that file in Google Earth and you will have access to your entire image. Limitations: GEST does not currently export annotations, ROIs, or vectors--just imagery.  FYI:  GEST does *NOT* in any way involve or reference the C# code listed in the comment tied to this contribution, which isn't very accurate or flexible.

New version uploaded on 08/09/09:  (1) Image backgrounds are now transparent in Google Earth.  (2) An easy-to-use procedural API for batch image processing is now available.  A .pro file with a documented example of using the API is packaged in the zip file.  This includes the ability to specify the stretch you want to apply to the image--without having to first display it in ENVI.  (3) If your image has an RPC or RSM sensor model and you've associated a DEM with it to increase ortho accuracy, that DEM is now honored during the superoverlay creation process.

New version uploaded on 11/11/09:  You can now supply a DEM directly to the procedural API instead of having to manually associate it with the image first.  This makes batch ortho-to-Google-Earth processes a lot easier and more accurate.

Archive contains functionality for IDL 6.3 and greater to enable IDL to host Microsoft Office Application Objects and a Spreadsheet Control.