Atmospheric correction using envi

Atmospheric correction using envi video tutorial with FLAASH
Any query's can be raised to him
wath the video
http://www.youtube.com/watch?v=4fiPRWixykU

ENVI Geoservices and ArcGIS® Online – A New Paradigm for Image Analytics

The development and release of ArcGIS® Online by Esri® ushered in a new era of GIS access and availability. ArcGIS Online allows organizations and individuals to manage and display their map data on the internet via an easy-to-use interface. This has been useful for GIS professionals who have been overloaded with small requests for geographic information by allowing their users to self-serve data and maps that have been developed and published by the GIS analyst. It also allows users in the field to display ground truth information that may be collected as a series of GPS points or geographic notes. According to Esri, “In addition, non-GIS professionals, such as knowledge workers who have a need for GIS, now have a way to quickly create maps from the unstructured information they work with in spreadsheets and text files and share these maps with others who can access them on any device. This type of on-demand and self-serve mapping frees up GIS professionals from having to respond to constant requests for maps and instead concentrate on making and publishing authoritative information products.” (Esri, June, 2012)

Along with map and display capabilities, ArcGIS Online comes equipped with the ability to conduct geo-processing tasks, or geoservices. Esri currently provides geocoding and network analysis geoservices, among others. Users with an ArcGIS for Server instance can also publish their own geoservices and models from the Esri software suite and consume them via ArcGIS Online. This means that customized workflows can be distributed via ArcGIS Online for consumption by non-technical users in the field. These services can be also be integrated into custom interfaces developed using the ArcGIS Web Mapping API’sor the ArcGIS Mobile Runtime SDK.

An ENVI Change Detection Geoservice in ArcGIS Online

Exelis Visual Information Solutions has worked very closely with Esri for years to develop interoperable solutions to leverage advanced image analytics from ENVI from within the ArcGIS ecosystem. Along with both desktop and server side interoperability, ENVI is now able to take advantage of the ArcGIS Online platform to expose ENVI geoservices in the cloud. Implemented using the ENVI Services Engine and the ArcGIS API for JavaScript, the app queries and consumes Landsat image services to run a number of different analysis tasks. Results are delivered back to the thin client as a visual representation, with links to download the processed datasets available if needed. Not only can this type of implementation run analysis and deliver results on remote data, the time-aware nature of the Landsat Image Service allows for time aware analysis to be conducted such as change detection, or in this case, NDVI analysis over time.

Displaying an NDVI Result from an Image Service in a Thin Client

This example of ENVI image analysis being run on image service data from the ArcGIS online environment is a snapshot of the future. In the same way that the storing and viewing of map products has migrated to the internet, so too will the analysis of large data be executed on large servers in remote locations and consumed via thin clients and mobile apps. What do you think? Are thin clients such as ArcGIS Online that consuming remote data and analysis functionality the future of GIS? Do you see a need in your organization for web-deployed analytics?
Read more

Download MODIS Conversion Toolkit (MCTK)

An easy-to-use plugin for processing and georeferencing every known MODIS product

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

download
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
New version created on 04/14/12:  Fixed geolocation issue for swaths that cross the Prime Meridian or International Dateline, added support for MOD16A2 and MOD16A3, updated list of supported products in user guide
New version created on 07/22/12: Added discussion on how to install plugin for use with ENVI 5.0+ Standard and Classic to user guide.

Download Google Earth Super-Overlay Tool (GEST)

Export full spatial resolution imagery to a Google-Earth-friendly format

***GEST only works in ENVI Classic (for now)***
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. 

download
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.

download GOSAT importer

download


























This extenstion is to import GOSAT data (HDF5 format). Currently this extension only supports ENVI Classic environment.

Support products: CAI L1B, CAI L1B+ (supports Polar Stereo), Cloud Flag, NDVI

The data (free) is available from this link below.
https://data.gosat.nies.go.jp/gateway/gateway/MenuPage/open.doopen.do?lang=en








[日本語]
ENVIのいぶき（GOSAT）データ対応の拡張プログラムです。現在は、ENVI Classic 環境のみでの対応となります。

サポートプロダクト: CAI L1B、 CAI L1B+ (ポーラーステレオ対応)、 Cloud Flag、 NDVI

いぶきデータは以下のサイトより無償で入手することが可能です（ユーザー登録が必要）。
https://data.gosat.nies.go.jp/gateway/gateway/MenuPage/open.doopen.do?lang=ja.

Hyperion Tools 2.0 Installation and User Guide

Author:

Devin White, PhD (Devin.White@gmail.com)

Introduction

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 u sing Hyperion data within ENVI.

Version 2.0 includes a complete overhaul of the underlying codebase, resulting in significantly faster conversion times, several new file output options, support for the new L1R format (L1R + AUX), and an application programming interface (API) that enables batch processing.  The API is presented after brief discussions on the installation and use of the plugin.

Download hyperion_tools.zip

Installation

To  add  the  toolkit  to  your  ENVI  installation,  place  the  hyperion_tools.sav, flag_mask_settings.txt, and hyperion_wl_fwhm_bbl.txt files in your ENVI save_add and/or extensions folder.  The location of this folder will vary by operating system and ENVI version.

ENVI 4.3:        Windows: c:\rsi\idl63\products\envi43\save_add

UNIX\Linux: /usr/local/rsi/idl_6.3/products/envi_4.3/save_add

Mac:  /applications/rsi/idl_6.3/products/envi_4.3/save_add

ENVI 4.4-4.8: Windows: c:\program files\itt\idlXX\products\enviXX\save_add UNIX\Linux: /usr/local/itt/idl_X.X/products/envi_X.X/save_add Mac:  /applications/itt/idl_X.X/products/envi_X.X/save_add

ENVI 5.0+ Standard:  Windows: c:\program files\exelis\enviXX\extensions UNIX\Linux: /usr/local/exelis/enviXX/extensions Mac:  /applications/exelis/enviXX/extensions

ENVI 5.0+ Classic:     Windows: c:\program files\exelis\enviXX\classic\save_add UNIX\Linux: /usr/local/exelis/enviXX /classic/save_add Mac:  /applications/exelis/enviXX /classic /save_add

NOTE:  To use Hyperion Tools in ENVI 5.0+, you must perform both the Standard and Classic mode installations.

To access the tools after installation, go to File->Open External File->EO-1->Hyperion Tools in

ENVI Classic or double-click on the “hyperion_tools” button in the Extensions folder in ENVI

5.0+.

L1R Processing

For L1R data, click on “Input HDF” and select your L1R file.  Then click on “Output Path” and select a destination folder for the new ENVI format version of the data.  Click “Apply” to start the conversion process.  In this mode, the conversion tool will place raw radiance data in the new ENVI file in BIL format and will include averaged wavelength and FWHM values.  The new file shares the same rootname as the input HDF, but the extension is “.dat”.

L1R Options:

·     Attempt Georeferencing:  If there is a metadata (.MET) file packaged with the L1R HDF

that resides in the same folder as the HDF file, and it shares the same rootname as the

HDF, the toolkit will parse the geographic coordinates for the four corners and include them in the new ENVI format file.  The projection is only pseudo-geographic.  Also, not all metadata files contain coordinates for the four corners, so the georeferencing might not work.

·    Use Flag Mask Correction:  A small number of Hyperion’s detectors are malfunctioning, which often results in vertical striping in the image that can vary from one band to the next.  Invoking this option gives you an image where the striping has been removed by replacing the bad values with ones linearly interpolated from the remaining good values on the same scan line.  The correction is done on the fly as the original data is retrieved from the HDF and is placed in the new ENVI format file.   The plugin uses the “flag_mask_settings.txt” file to guide the correction process.   This file  contains pre- launch detector health information on a per-pixel, per-band basis (256 x 242); it is also present in every L1R HDF file.   You can modify the file to reflect post-launch health changes (0 = good, 1 = bad).

·    Output ENVI Mask Image:   This option instructs the toolkit to create an ENVI mask image (1 = good data, 0 = bad data) for the data set that suppresses the data acquired by the malfunctioning detectors.  This especially helps when carrying out PCA rotations, Fourier Transforms, and Hourglass Processing with raw data that has not been flag- corrected.  The mask image has the same basic rootname as the converted data file, but has “_mask.dat” appended to it.

·    Output Wavelength/FWHM Tables:   Comma-delimited text files (CSV) are generated that include wavelength and full-width half maximum values for every band of every detector.   These data are pulled directory from the supplied L1R file.   The tables are organized so that bands (242) are the columns and detectors (256) are the rows.  Bands increase from left to right and detectors increase from top to bottom.

·    Output FLAASH Scale Factors:   A small text file is generated in the specified output folder  that  contains  scale  factors  necessary  to  correctly  input  Hyperion  data  into FLAASH. These scale factors are static (not derived from the inputted L1R file).

·    Interpolate Data to Common Wavelength Set:   Each detector in Hyperion’s pushbroom array has slightly different band center and FWHM values for each band.  This option performs a linear or quadratic interpolation across all detectors on a pixel by pixel, spectrum by spectrum, basis to a common set of wavelengths.  The Bad Bands List is honored in this process as well to ensure the best possible results.  The interpolation occurs  on-the-fly  during data  conversion.    The converted  file  includes  wavelengths representing the  new  common set of  band  centers. Averaged  values are  used  for FWHM.  Linear interpolation is used unless the Quadratic button is toggled to “Yes”.

·    Use Quadratic Method:  Toggle this button to “Yes” to use quadratic interpolation.  The button becomes active when the user checks the Interpolate Data to Common Wavelength Set box.

L1G/T Processing

For L1G/1T data, click on “Input MTL” and select the “.L1G” or “.LIT” metadata file that is packaged with the HDF or GeoTIFF files.  Then click on “Output Path” and select a destination folder for the new ENVI format version of the data.   Click “Apply” to start the conversion

process.  In this mode, the conversion tool will place the radiance data in the new ENVI file in BIL format and will include averaged wavelength and FWHM values.  The new file shares the same rootname as the input files, but the extension is “.dat”.  All 242 files must be in the same folder as the MTL metadata file for the conversion to take place.

L1G/T Options:

·    Output ENVI Mask Image:   This option instructs the toolkit to create an ENVI mask image  (1=good  data,  0=bad  data)  for  the  data  set  that  suppresses  the  “black” background present in the georeferenced imagery.   This is useful for almost all ENVI

processing since the background values are not part of the original dataset.  The mask

image has the same basic rootname as the converted data file, but has “_mask.dat”

appended to it.

·    Output FLAASH Scale Factors:   A small text file is generated in the specified output folder  that  contains  scale  factors  necessary  to  correctly  input  Hyperion  data  into FLAASH. These scale factors are static (not derived from the inputted L1G/T file).

·    Output Interleave:  The interleave of the outputted cube can be set to Band Sequential (BSQ), Band Interleaved By Line (BIL), or Band Interleaved By Pixel (BIP).  BIL is the default option.

Using Hyperion Tools Output in FLAASH

To use toolkit output in FLAASH, go into the header file for the output and remove the f irst seven bands from the Bad Bands List. When FLAASH is done, go into the header file for the new output and put the seven bands back on the list.